feat(debug): add debug read with CSV export

- Parse F1 debug data via family-independent temp formula
  (bits 4-14 scaled by 2**(i-8), sign at bit 0)
- Save sensor+debug temps side-by-side to debug_info.csv
- Wire READ DEBUG button in StatusActionsPanel
- Rename ReplayChart → RunChart; move into GraphTab
- Extract PanelBox/SectionTitle/PanelSlider in ReadoutPanel
  to cut ~300 lines of duplicated styling
- Add rightRailWidth token to Theme for consistent rail sizing
- Wrap ReadoutPanel in ScrollView so Thresholds card stays
  reachable when E-C delta rows appear

.gitignore

@@ -40,3 +40,21 @@ dist/
 *.spec
 *.icns
 *.ico
+
+# Runtime scratch data
+tmp/
+
+# Superpowers brainstorming visual companion
+.superpowers/
+.llm-wiki/
+.agents/
+.pi/
+
+# Planning / personal docs (root level)
+CLAUDE.md
+LEARNINGS.md
+MIGRATION.md
+AGENTS.md
+CONVENTIONS.md
+specs/
+graphify-out/

Makefile

@@ -3,14 +3,14 @@
 install:
 	uv sync
 
-test:
+test: lint
 	uv run pytest tests/
 
 lint:
-	uv run ruff check src/
+	uv run ruff check src/ tests/
 
 fix:
-	uv run ruff check src/ --fix
+	uv run ruff check src/ tests/ --fix
 
 typecheck:
 	uv run mypy src/

README.md

@@ -14,11 +14,13 @@ The `ISenseCloud` application provides a real-time monitor and analysis dashboar
 - **Custom Safety Limits & Thresholds**: Configurable alarm thresholds and set-points with automatic alerts when temperatures diverge from normal boundaries.
 
 ### App Showcase
+
 ![ISenseCloud UI displaying successful connection on COM6](image-1.png)
 *Figure 1: Main Status Dashboard displaying successful connection, active serial communications, and automated logging terminal.*
 
 > [!NOTE]
 > **Take Screenshots for Visual Placeholders:**
+>
 > - **Wafer Heatmap Tab**: Take a screenshot of the Wafer Map tab showing the radial heatmap interpolation, save it to `docs/design/wafer_heatmap_tab.png` and add it here.
 > - **Temperature Trend Graph**: Take a screenshot of the Graph tab plotting multi-sensor trend lines, save it to `docs/design/temp_trend_tab.png` and add it here.
 
@@ -42,12 +44,15 @@ During the refactoring from the flat-layout prototype (`SettingTab` branch) to t
 From the project root:
 
 ### Option A: Using `uv` (Recommended)
+
 If you have [uv](https://docs.astral.sh/uv/) installed:
+
 ```bash
 uv sync
 ```
 
 ### Option B: Using `pip`
+
 ```bash
 python3 -m venv .venv
 source .venv/bin/activate   # or .venv\Scripts\activate on Windows
@@ -59,19 +64,21 @@ pip install -e .            # install the `pygui` package (src/ layout) in edita
 ## Run
 
 ### Launch PySide6 QML App
+
 ```bash
 make run
 ```
+
 This launches the Qt window and loads the `ISC` QML module from `src/pygui/ISC/Main.qml`.
 
 ## Development
 
-The project uses `uv` for dependency management and tooling, `Ruff` for linting and formatting, `Mypy` for static type checking, and `pytest` for unit tests. 
+The project uses `uv` for dependency management and tooling, `Ruff` for linting and formatting, `Mypy` for static type checking, and `pytest` for unit tests.
 
 A `Makefile` is provided to simplify common development and verification tasks:
 
 | Command | Description |
-|---------|-------------|
+| --------- | ------------- |
 | `make install` | Sync dependencies and set up the local `.venv` using `uv` |
 | `make run` | Launch the ISenseCloud application |
 | `make test` | Run the `pytest` test suite |
@@ -83,6 +90,7 @@ A `Makefile` is provided to simplify common development and verification tasks:
 ### Ruff Configuration
 
 Ruff is configured in `pyproject.toml` to enforce:
+
 - **E/W**: Pycodestyle errors and warnings
 - **F**: Pyflakes linter rules
 - **I**: Import sorting (isort parity)
@@ -174,11 +182,13 @@ Window {
 - If the app does not start, verify the virtual environment is active and dependencies are installed:
 
   *Using `uv`:*
+
   ```bash
   uv sync
   ```
 
   *Using `pip`:*
+
   ```bash
   source .venv/bin/activate   # or .venv\Scripts\activate on Windows
   pip install -r requirements.txt
@@ -186,18 +196,21 @@ Window {
 
 - If no window appears, ensure you are running in a desktop session with GUI access.
 
-- **Windows COM Port Connection Issues:** 
-  * Standard Windows serial drivers don't support custom baud rates (e.g. `888888`), throwing an expected `OSError(22)` warning before falling back to `115200` baud.
+- **Windows COM Port Connection Issues:**
+  - Standard Windows serial drivers don't support custom baud rates (e.g. `888888`), throwing an expected `OSError(22)` warning before falling back to `115200` baud.
 
 ### Step-by-Step Windows Simulator Connection Guide
 
 #### Step 1: Create the Virtual Serial Port Bridge
+
 Open **HHD Virtual Serial Port Tools**. Under the **Local Bridges** panel on the left, click the green **`+`** (Add) button to create a new port pair. Configure it to bridge **`COM5 ↔ COM6`**.
 
 ![HHD Virtual Serial Port Tools showing COM5 ↔ COM6 Local Bridge](image.png)
 
 #### Step 2: Configure and Start the Wafer Simulator
+
 Launch the **Wafer Simulator Control Panel** (`wafer_sim_gui.py`):
+
 1. Set the **Serial Port** to **`COM5`**.
 2. **Uncheck** the `Auto-create Virtual Port (com0com)` checkbox.
 3. Choose your desired **Wafer Type** (e.g., `aepwafer`) and **Family Code** (e.g., `A`).
@@ -206,6 +219,7 @@ Launch the **Wafer Simulator Control Panel** (`wafer_sim_gui.py`):
 ![Wafer Simulator Control Panel configured on COM5 and streaming](image-2.png)
 
 #### Step 3: Run the UI and Connect
+
 Launch the `pygui` client application. On the left navigation rail, click **DETECT WAFER**. The application will scan all active COM ports, automatically detect the virtual wafer simulator on **`COM6`**, and update the status indicator to **Connected** (green).
 
 ![ISenseCloud UI displaying successful connection on COM6](image-1.png)

pyproject.toml

@@ -18,6 +18,7 @@ dependencies = [
     "scipy>=1.17.1",
     "pyyaml>=6.0.3",
     "dtw-python",
+    "cryptography>=41.0",
 ]
 
 [project.optional-dependencies]

src/pygui/ISC/AboutDialog.qml

@@ -1,5 +1,6 @@
 import QtQuick
 import QtQuick.Controls
+import QtQuick.Dialogs
 import QtQuick.Layouts
 import ISC
 
@@ -8,10 +9,12 @@ Popup {
     modal: true
     dim: true
     closePolicy: Popup.CloseOnEscape | Popup.CloseOnPressOutside
-    width: 420
-    height: 340
+    width: 600
+    height: 500
     anchors.centerIn: Overlay.overlay
 
+    onOpened: licenseModel.refresh()
+
     background: Rectangle {
         radius: Theme.radiusMd
         color: Theme.cardBackground
@@ -19,10 +22,17 @@ Popup {
         border.width: 1
     }
 
+    FileDialog {
+        id: licenseFileDialog
+        title: "Load License"
+        nameFilters: ["License files (*.bin)"]
+        onAccepted: loadFailedLabel.visible = !licenseModel.loadLicenseFile(selectedFile.toString())
+    }
+
     ColumnLayout {
         anchors.fill: parent
-        anchors.margins: 24
-        spacing: 16
+        anchors.margins: 28
+        spacing: 20
 
         // ── Title ──
         Label {
@@ -34,27 +44,20 @@ Popup {
 
         // ── App info ──
         ColumnLayout {
-            spacing: 4
+            spacing: 6
 
             Label {
-                text: "ISenseCloud (ISC)"
-                font.pixelSize: Theme.fontLg
+                text: "ISenseCloud"
+                font.pixelSize: Theme.fontXl
+                font.bold: true
                 color: Theme.headingColor
             }
 
             Label {
-                text: "Version 0.1.0"
-                font.pixelSize: Theme.fontSm
+                text: "Version " + appVersion
+                font.pixelSize: Theme.fontMd
                 color: Theme.bodyColor
             }
-
-            Label {
-                text: "Temperature-sensing wafer monitoring"
-                font.pixelSize: Theme.fontSm
-                color: Theme.bodyColor
-                wrapMode: Text.WordWrap
-                Layout.fillWidth: true
-            }
         }
 
         // ── Separator ──
@@ -67,7 +70,8 @@ Popup {
         // ── License grid ──
         Rectangle {
             Layout.fillWidth: true
-            Layout.preferredHeight: 100
+            Layout.fillHeight: true
+            Layout.minimumHeight: 150
             radius: Theme.radiusSm
             color: Theme.panelBackground
             border.color: Theme.cardBorder
@@ -75,23 +79,38 @@ Popup {
 
             ColumnLayout {
                 anchors.fill: parent
-                anchors.margins: 10
-                spacing: 2
+                anchors.margins: 14
+                spacing: 6
 
-                Label {
-                    text: "LICENSE"
-                    color: Theme.panelTitleText
-                    font.pixelSize: Theme.fontXs
-                    font.letterSpacing: 0.5
+                RowLayout {
+                    Layout.fillWidth: true
+
+                    Label {
+                        text: "LICENSE"
+                        color: Theme.panelTitleText
+                        font.pixelSize: Theme.fontSm
+                        font.bold: true
+                        font.letterSpacing: 0.5
+                        Layout.fillWidth: true
+                    }
+
+                    Label {
+                        id: loadFailedLabel
+                        visible: false
+                        text: "Invalid license file"
+                        color: Theme.statusWarningColor
+                        font.pixelSize: Theme.fontSm
+                    }
                 }
 
                 // Grid header
                 RowLayout {
                     Layout.fillWidth: true
-                    spacing: 4
-                    Label { text: "Wafer SN"; font.pixelSize: Theme.fontXs; font.bold: true; color: Theme.subheadingColor; Layout.preferredWidth: 100 }
-                    Label { text: "Mfg Date"; font.pixelSize: Theme.fontXs; font.bold: true; color: Theme.subheadingColor; Layout.preferredWidth: 80 }
-                    Label { text: "Level"; font.pixelSize: Theme.fontXs; font.bold: true; color: Theme.subheadingColor; Layout.preferredWidth: 60 }
+                    spacing: 8
+                    Label { text: "Wafer SN"; font.pixelSize: Theme.fontSm; font.bold: true; color: Theme.subheadingColor; Layout.preferredWidth: 150 }
+                    Label { text: "Mfg Date"; font.pixelSize: Theme.fontSm; font.bold: true; color: Theme.subheadingColor; Layout.preferredWidth: 120 }
+                    Label { text: "Level"; font.pixelSize: Theme.fontSm; font.bold: true; color: Theme.subheadingColor; Layout.preferredWidth: 80 }
+                    Label { text: "License Date"; font.pixelSize: Theme.fontSm; font.bold: true; color: Theme.subheadingColor; Layout.fillWidth: true }
                 }
 
                 Rectangle {
@@ -100,10 +119,27 @@ Popup {
                     color: Theme.softBorder
                 }
 
+                ListView {
+                    Layout.fillWidth: true
+                    Layout.fillHeight: true
+                    clip: true
+                    visible: licenseModel.licenses.length > 0
+                    model: licenseModel.licenses
+                    delegate: RowLayout {
+                        width: ListView.view.width
+                        spacing: 8
+                        Label { text: modelData.serial; font.pixelSize: Theme.fontMd; color: Theme.bodyColor; Layout.preferredWidth: 150 }
+                        Label { text: modelData.mfgDate; font.pixelSize: Theme.fontMd; color: Theme.bodyColor; Layout.preferredWidth: 120 }
+                        Label { text: modelData.level; font.pixelSize: Theme.fontMd; color: Theme.bodyColor; Layout.preferredWidth: 80 }
+                        Label { text: modelData.licDate; font.pixelSize: Theme.fontMd; color: Theme.bodyColor; Layout.fillWidth: true }
+                    }
+                }
+
                 Label {
+                    visible: licenseModel.licenses.length === 0
                     text: "No license loaded"
                     color: Theme.bodyColor
-                    font.pixelSize: Theme.fontSm
+                    font.pixelSize: Theme.fontMd
                     Layout.fillWidth: true
                     Layout.fillHeight: true
                     verticalAlignment: Text.AlignVCenter
@@ -112,25 +148,55 @@ Popup {
             }
         }
 
-        // ── Close ──
-        Button {
-            text: "Close"
-            Layout.alignment: Qt.AlignRight
-            Layout.preferredWidth: 100
-            Layout.preferredHeight: 32
-            onClicked: root.close()
+        // ── Buttons ──
+        RowLayout {
+            Layout.fillWidth: true
+            spacing: 12
 
-            background: Rectangle {
-                radius: Theme.radiusSm
-                color: parent.hovered ? Theme.buttonNeutralHover : Theme.buttonNeutralBackground
-                border.color: Theme.fieldBorder
-                border.width: 1
+            Button {
+                text: "Load License"
+                Layout.preferredWidth: 140
+                Layout.preferredHeight: 36
+                onClicked: licenseFileDialog.open()
+
+                background: Rectangle {
+                    radius: Theme.radiusSm
+                    color: parent.hovered ? Theme.buttonNeutralHover : Theme.buttonNeutralBackground
+                    border.color: Theme.fieldBorder
+                    border.width: 1
+                }
+                contentItem: Label {
+                    text: parent.text
+                    color: Theme.buttonNeutralText
+                    font.pixelSize: Theme.fontMd
+                    font.bold: true
+                    horizontalAlignment: Text.AlignHCenter
+                    verticalAlignment: Text.AlignVCenter
+                }
             }
-            contentItem: Label {
-                text: parent.text
-                color: Theme.buttonNeutralText
-                horizontalAlignment: Text.AlignHCenter
-                verticalAlignment: Text.AlignVCenter
+
+            Item { Layout.fillWidth: true }
+
+            Button {
+                text: "Close"
+                Layout.preferredWidth: 100
+                Layout.preferredHeight: 36
+                onClicked: root.close()
+
+                background: Rectangle {
+                    radius: Theme.radiusSm
+                    color: parent.hovered ? Theme.buttonNeutralHover : Theme.buttonNeutralBackground
+                    border.color: Theme.fieldBorder
+                    border.width: 1
+                }
+                contentItem: Label {
+                    text: parent.text
+                    color: Theme.buttonNeutralText
+                    font.pixelSize: Theme.fontMd
+                    font.bold: true
+                    horizontalAlignment: Text.AlignHCenter
+                    verticalAlignment: Text.AlignVCenter
+                }
             }
         }
     }

src/pygui/ISC/HomePage.qml

@@ -19,19 +19,45 @@ Rectangle {
 
     // ===== View State =====
     property int selectedTabIndex: 0
+    onSelectedTabIndexChanged: {
+        if (selectedTabIndex === 2) {
+            file_browser.refreshFiles();
+            streamController.unloadFile()
+        } else if (streamController.mode === "live") {
+            // Leaving the map tab mid-stream: stop and blank the live map.
+            streamController.setMode("review")
+        }
+    }
+
+
 
     property bool memoryRead: false
     property bool waferDetected: false
+    // TODO P2.2: add `property bool waferLicensed: false`; set it in
+    //   onDetectResult below via deviceController.waferLicensed() (slot from
+    //   P1.2 — the detectResult payload is opaque in QML, can't read serial
+    //   from it). Then READ/ERASE buttons get
+    //   `enabled: root.waferDetected && root.waferLicensed`.
+    //   See docs/pending/license-gating-plan.md §2.2.
 
     Connections {
         target: deviceController
         function onDetectResult(result){
-            root.waferDetected = (result != null && result != undefined)
+            // detectResult payload is Signal(object): a dict may cross into QML
+            // as an opaque wrapper whose fields read as undefined, so only
+            // test truthiness (None on failure, dict on success).
+            root.waferDetected = !!result
         }
         function onParsedDataReady(result) {
             if (result.success && result.csv_path) {
                 streamController.loadFile(result.csv_path)
+                // TODO P3.1: only auto-jump to Map when unlocked:
+                //   `&& licenseModel.licenses.length > 0` — otherwise a
+                //   successful read walks straight into the locked tab.
+                //   See plan §3.1.
+                if (root.selectedTabIndex === 0) {
                 root.selectedTabIndex = 2
+                }
             }
         }
     }
@@ -55,6 +81,7 @@ Rectangle {
 
     function _doDetect() {
         root.memoryRead = false
+        root.waferDetected = false
         streamController.setMode("review")
         streamController.stopStream()
         deviceController.detectWafer()
@@ -64,11 +91,18 @@ Rectangle {
         id: saveDirDialog
         title: "Choose a folder to save Data"
         onAccepted: {
-            deviceController.setSaveDataDir(root.cleanFolderUrl(selectedFolder))
+            var dir = root.cleanFolderUrl(selectedFolder)
+            deviceController.setSaveDataDir(dir)
+            file_browser.setCurrentDirectory(dir)
             root._doDetect()
         }
     }
 
+    // ===== Split Dialog (Threshold Segmentation) =====
+    SplitDialog {
+        id: splitDialog
+    }
+
     // ===== Settings Popup =====
     Popup {
         id: settingsPopup
@@ -168,8 +202,6 @@ Rectangle {
             Layout.preferredWidth: Theme.sideRailWidth
             Layout.fillHeight: true
             color: Theme.sideRailBackground
-            border.color: Theme.sideBorder
-            border.width: 1
 
             ColumnLayout {
                 anchors.fill: parent
@@ -188,9 +220,30 @@ Rectangle {
 
                     ListModel {
                         id: pillModel
-                        ListElement { label: "STATUS"; icon: "Tabs/icons/status.svg"; expandW: 86 }
-                        ListElement { label: "DATA";   icon: "Tabs/icons/data.svg";   expandW: 66 }
-                        ListElement { label: "MAP";    icon: "Tabs/icons/map.svg";    expandW: 58 }
+                        ListElement {
+                            label: "STATUS"
+                            icon: "Tabs/icons/status.svg"
+                            expandW: 86
+                            desc: "Monitor real-time device connection, serial communication, and execute wafer actions."
+                        }
+                        ListElement {
+                            label: "DATA"
+                            icon: "Tabs/icons/data.svg"
+                            expandW: 66
+                            desc: "Manage, review, compare (DTW), and split historical sensor data records."
+                        }
+                        ListElement {
+                            label: "MAP"
+                            icon: "Tabs/icons/map.svg"
+                            expandW: 58
+                            desc: "Visualize spatial sensor readings on a 2D thin-plate spline RBF interpolated heatmap."
+                        }
+                        ListElement {
+                            label: "GRAPH"
+                            icon: "Tabs/icons/bar-chart.svg"
+                            expandW: 70
+                            desc: "Whole-run multi-sensor temperature chart for the currently loaded file."
+                        }
                     }
 
                     RowLayout {
@@ -271,345 +324,306 @@ Rectangle {
                                     }
                                 }
 
+                                AppToolTip {
+                                    visible: pillBtn.hovered
+                                    text: "<b>" + model.label + "</b>: " + model.desc
+                                }
+
                                 onClicked: root.selectedTabIndex = index
                             }
                         }
                     }
                 }
 
-                // ── BOX 2: Context-Sensitive Rail Panel ────────────────────
+                // ── BOX 1.5: Run Comparison (Data tab only) ────────────────
                 Rectangle {
+                    id: runComparisonBox
                     Layout.fillWidth: true
-                    Layout.fillHeight: true
-                    Layout.minimumHeight: 120
+                    Layout.preferredHeight: runCompCol.implicitHeight + 28
+                    visible: root.selectedTabIndex === 1
                     radius: Theme.sidePanelRadius
                     border.color: Theme.sideBorder
                     border.width: 1
                     color: Theme.sidePanelBackground
 
+                    readonly property var dataTab: dataTabLoader.item
+
+                    component RunSlot: Rectangle {
+                        id: slotBox
+                        property string title
+                        property string filePath: ""
+                        property color accent: Theme.primaryAccent
+                        property bool active: false
+                        property bool locked: false
+                        property string placeholderText: "Click to select"
+                        signal cleared()
+                        signal armed()
+
+                        Layout.fillWidth: true
+                        implicitHeight: 58
+                        radius: Theme.radiusSm
+                        color: Theme.fieldBackground
+                        opacity: slotBox.locked ? 0.65 : 1.0
+                        border.width: slotBox.active ? 2 : 1
+                        border.color: slotBox.active ? accent : Theme.sideBorder
+
+                        Behavior on border.color { ColorAnimation { duration: Theme.durationFast } }
+
+                        MouseArea {
+                            anchors.fill: parent
+                            enabled: !slotBox.locked
+                            cursorShape: slotBox.locked ? Qt.ArrowCursor : Qt.PointingHandCursor
+                            onClicked: slotBox.armed()
+                        }
+
+                        RowLayout {
+                            anchors.fill: parent
+                            anchors.margins: 10
+                            spacing: 8
+
+                            Rectangle {
+                                width: 8; height: 8; radius: 4
+                                color: slotBox.accent
+                                Layout.alignment: Qt.AlignVCenter
+                            }
+
+                            ColumnLayout {
+                                Layout.fillWidth: true
+                                spacing: 2
+                                Label {
+                                    text: slotBox.title
+                                    font.pixelSize: Theme.fontXs
+                                    font.bold: true
+                                    font.letterSpacing: 1.0
+                                    color: slotBox.active ? slotBox.accent : Theme.sideMutedText
+                                }
+                                Label {
+                                    text: slotBox.filePath !== ""
+                                        ? slotBox.filePath.split("/").pop()
+                                        : (slotBox.locked ? slotBox.placeholderText : (slotBox.active ? "<- Select file below..." : "Click to select"))
+                                    font.pixelSize: Theme.fontSm
+                                    color: slotBox.filePath !== "" ? Theme.headingColor : Theme.bodyColor
+                                    opacity: slotBox.filePath !== "" ? 1.0 : 0.6
+                                    elide: Text.ElideMiddle
+                                    Layout.fillWidth: true
+                                }
+                            }
+
+                            Button {
+                                visible: slotBox.filePath !== "" && !slotBox.locked
+                                flat: true
+                                implicitWidth: 24; implicitHeight: 24
+                                onClicked: slotBox.cleared()
+                                background: Rectangle {
+                                    radius: Theme.radiusSm
+                                    color: parent.hovered ? Theme.flatButtonHover : "transparent"
+                                }
+                                contentItem: IconImage {
+                                    source: "Tabs/icons/x.svg"
+                                    width: 14; height: 14
+                                    sourceSize.width: 14
+                                    sourceSize.height: 14
+                                    color: Theme.bodyColor
+                                    anchors.centerIn: parent
+                                }
+                            }
+                        }
+                    }
+
                     ColumnLayout {
+                        id: runCompCol
                         anchors.fill: parent
                         anchors.margins: 14
-                        spacing: 8
+                        spacing: 10
 
-                        StackLayout {
+                        RowLayout {
                             Layout.fillWidth: true
-                            Layout.fillHeight: true
-                            currentIndex: root.selectedTabIndex
+                            spacing: 8
 
-                            // ── Status tab: Hardware Actions ────────────────
-                            ColumnLayout {
-                                spacing: 6
-
-                                Label {
-                                    text: "HARDWARE ACTIONS"
-                                    color: Theme.sideMutedText
-                                    font.family: Theme.uiFontFamily
-                                    font.pixelSize: Theme.fontSm
-                                    topPadding: 6
-                                    font.letterSpacing: 1.5
-                                    font.bold: true
-                                }
-
-                                RailActionButton {
-                                    label: "DETECT WAFER"
-                                    iconSource: "../icons/detect.svg"
-                                    Layout.fillWidth: true
-                                    enabled: !deviceController.isDetecting
-                                    onClicked: root._doDetect()
-                                }
-
-                                RailActionButton {
-                                    label: "READ MEMORY"
-                                    iconSource: "../icons/read.svg"
-                                    Layout.fillWidth: true
-                                    enabled: root.waferDetected
-                                    onClicked: deviceController.readMemoryAsync()
-                                }
-
-                                RailActionButton {
-                                    label: "ERASE MEMORY"
-                                    iconSource: "../icons/erase.svg"
-                                    Layout.fillWidth: true
-                                    destructive: true
-                                    enabled: root.waferDetected
-                                    onClicked: deviceController.eraseMemory(
-                                        deviceController.selectedPort)
-                                }
-
-                                Item { Layout.fillHeight: true }
-                            }
-
-                            // ── Data tab: Data Operations ───────────────────
-                            ColumnLayout {
-                                spacing: 6
-
-                                Label {
-                                    text: "DATA OPERATIONS"
-                                    color: Theme.sideMutedText
-                                    font.family: Theme.uiFontFamily
-                                    font.pixelSize: Theme.fontSm
-                                    topPadding: 6
-                                    font.letterSpacing: 1.5
-                                    font.bold: true
-                                }
-
-                                RailActionButton {
-                                    label: "OPEN IN EXCEL"
-                                    iconSource: "../icons/excel.svg"
-                                    Layout.fillWidth: true
-                                    onClicked: deviceController.openCsvFile()
-                                }
-
-                                RailActionButton {
-                                    label: "COMPARE CSV"
-                                    iconSource: "../icons/compare.svg"
-                                    Layout.fillWidth: true
-                                    onClicked: console.log("[P3.1] Compare dialog not yet built")
-                                }
-
-                                RailActionButton {
-                                    label: "SPLIT DATA"
-                                    iconSource: "../icons/split.svg"
-                                    Layout.fillWidth: true
-                                    onClicked: console.log("[P3.2] Split dialog not yet built")
-                                }
-
-                                Item { Layout.fillHeight: true }
-                            }
-
-                            // ── Map tab: Source file browser ──────────────
-                            SourcePanel {
+                            Label {
+                                text: "RUN COMPARISON (DTW)"
+                                color: Theme.sideMutedText
+                                font.family: Theme.uiFontFamily
+                                font.pixelSize: Theme.fontSm
+                                font.letterSpacing: 1.5
+                                font.bold: true
                                 Layout.fillWidth: true
-                                Layout.fillHeight: true
+                                elide: Text.ElideRight
                             }
+
+                            Button {
+                                id: resetRunBtn
+                                flat: true
+                                implicitWidth: 32
+                                implicitHeight: 32
+                                visible: true
+                                onClicked: if (runComparisonBox.dataTab) runComparisonBox.dataTab.resetComparison()
+
+                                background: Rectangle {
+                                    radius: Theme.radiusSm
+                                    color: resetRunBtn.hovered ? Theme.flatButtonHover : "transparent"
+                                }
+                                contentItem: IconImage {
+                                    source: "Tabs/icons/rotate-ccw.svg"
+                                    width: 18; height: 18
+                                    sourceSize.width: 18
+                                    sourceSize.height: 18
+                                    color: Theme.bodyColor
+                                    anchors.centerIn: parent
+                                }
+                                AppToolTip {
+                                    visible: resetRunBtn.hovered
+                                    text: "Reset comparison"
+                                }
+                            }
+                        }
+
+                        PanelCheckBox {
+                            id: useMasterCheck
+                            Layout.fillWidth: true
+                            text: "Compare vs Master File"
+                            checked: runComparisonBox.dataTab ? runComparisonBox.dataTab.useMasterFile : false
+                            onToggled: {
+                                if (!runComparisonBox.dataTab) return
+                                runComparisonBox.dataTab.useMasterFile = checked
+                                if (checked) runComparisonBox.dataTab.activeBox = 2
+                            }
+                        }
+
+                        RunSlot {
+                            readonly property bool useMaster: runComparisonBox.dataTab ? runComparisonBox.dataTab.useMasterFile : false
+                            title: useMaster ? "MASTER FILE" : "REFERENCE (RUN A)"
+                            accent: Theme.primaryAccent
+                            locked: useMaster
+                            placeholderText: useMaster
+                                ? (runComparisonBox.dataTab.runBWaferType !== ""
+                                    ? "No master file for type " + runComparisonBox.dataTab.runBWaferType
+                                    : "Select Run B to resolve master")
+                                : "Click to select"
+                            active: runComparisonBox.dataTab ? (!useMaster && runComparisonBox.dataTab.activeBox === 1) : false
+                            filePath: runComparisonBox.dataTab
+                                ? (useMaster ? runComparisonBox.dataTab.masterFileForRunB : runComparisonBox.dataTab.compareFileA)
+                                : ""
+                            onArmed: if (runComparisonBox.dataTab && !useMaster) runComparisonBox.dataTab.activeBox = 1
+                            onCleared: {
+                                if (!runComparisonBox.dataTab) return
+                                runComparisonBox.dataTab.compareFileA = ""
+                                runComparisonBox.dataTab.activeBox = 1
+                                runComparisonBox.dataTab.clearResults()
+                            }
+                        }
+
+                        RunSlot {
+                            title: "SESSION (RUN B)"
+                            accent: Theme.themeSkill
+                            active: runComparisonBox.dataTab ? runComparisonBox.dataTab.activeBox === 2 : false
+                            filePath: runComparisonBox.dataTab ? runComparisonBox.dataTab.compareFileB : ""
+                            onArmed: if (runComparisonBox.dataTab) runComparisonBox.dataTab.activeBox = 2
+                            onCleared: {
+                                if (!runComparisonBox.dataTab) return
+                                runComparisonBox.dataTab.compareFileB = ""
+                                runComparisonBox.dataTab.activeBox = 2
+                                runComparisonBox.dataTab.clearResults()
+                            }
+                        }
+
+                        Button {
+                            id: compareRunBtn
+                            Layout.fillWidth: true
+                            Layout.preferredHeight: 32
+                            readonly property var dt: runComparisonBox.dataTab
+                            readonly property string fileA: !!dt ? (dt.useMasterFile ? dt.masterFileForRunB : dt.compareFileA) : ""
+                            readonly property bool masterMissing: !!dt && dt.useMasterFile && dt.masterFileForRunB === ""
+                            readonly property bool sameFile: !!dt && fileA !== "" && fileA === dt.compareFileB
+                            readonly property string gateError: !!dt ? dt.familyGateError : ""
+                            enabled: !!dt && fileA !== "" && dt.compareFileB !== "" && !sameFile && !dt.comparing && !masterMissing && gateError === ""
+                            AppToolTip {
+                                visible: (compareRunBtn.sameFile || compareRunBtn.masterMissing || compareRunBtn.gateError !== "") && compareRunBtn.hovered
+                                text: compareRunBtn.masterMissing
+                                    ? "No master file registered for this wafer type (Settings → Master Files)"
+                                    : compareRunBtn.gateError !== "" ? compareRunBtn.gateError
+                                    : "Choose two different runs to compare"
+                            }
+                            onClicked: {
+                                dt.comparing = true
+                                dt.clearResults()
+                                streamController.compareFiles(fileA, dt.compareFileB)
+                            }
+
+                            background: Rectangle {
+                                radius: Theme.radiusSm
+                                color: compareRunBtn.enabled
+                                    ? (compareRunBtn.hovered ? Qt.lighter(Theme.primaryAccent, 1.1) : Theme.primaryAccent)
+                                    : Theme.buttonNeutralBackground
+                                Behavior on color { ColorAnimation { duration: Theme.durationFast } }
+                            }
+                            contentItem: Row {
+                                spacing: 8
+                                anchors.centerIn: parent
+                                Label {
+                                    anchors.verticalCenter: parent.verticalCenter
+                                    text: !compareRunBtn.dt ? "Select both runs"
+                                        : compareRunBtn.dt.comparing
+                                            ? "Comparing…"
+                                            : compareRunBtn.enabled
+                                                ? "Run DTW Comparison"
+                                                : (compareRunBtn.masterMissing ? "No master for this type"
+                                                    : compareRunBtn.sameFile ? "Choose different runs"
+                                                    : compareRunBtn.gateError !== "" ? "Wafer family mismatch"
+                                                    : "Select both runs")
+                                    color: compareRunBtn.enabled ? Theme.tone100 : Theme.sideMutedText
+                                    font.pixelSize: Theme.fontSm
+                                    font.bold: true
+                                }
+                                BusyIndicator {
+                                    running: !!compareRunBtn.dt && compareRunBtn.dt.comparing
+                                    visible: !!compareRunBtn.dt && compareRunBtn.dt.comparing
+                                    width: 14; height: 14
+                                    anchors.verticalCenter: parent.verticalCenter
+                                }
+                            }
+                        }
+                    }
+                }
+
+                // ── BOX 2: Context-Sensitive Rail Panel ────────────────────
+                StackLayout {
+                    Layout.fillWidth: true
+                    Layout.fillHeight: true
+                    Layout.minimumHeight: 120
+                    currentIndex: root.selectedTabIndex === 0 ? 0 : 1
+
+                    // ── Status tab: Hardware Actions + Log Actions ──────────
+                    StatusActionsPanel {
+                        Layout.fillWidth: true
+                        Layout.fillHeight: true
+                    }
+
+                    // ── Map tab: Source file browser ──────────────
+                    Rectangle {
+                        radius: Theme.sidePanelRadius
+                        border.color: Theme.sideBorder
+                        border.width: 1
+                        color: Theme.sidePanelBackground
+
+                        SourcePanel {
+                            anchors.fill: parent
+                            anchors.margins: 14
                         }
                     }
                 }
 
                 // ── BOX 3: Hardware Status Footer ──────────────────────────
-                Rectangle {
+                ConnectionFooter {
                     Layout.fillWidth: true
-                    Layout.preferredHeight: Theme.sideFooterConnection
-                    radius: Theme.sidePanelRadius
-                    border.color: Theme.sideBorder
-                    border.width: 1
-                    color: Theme.sidePanelBackground
-
-                    ColumnLayout {
-                        anchors.fill: parent
-                        anchors.margins: 14
-                        spacing: 6
-
-                        // Row 1: Title + status badge (unchanged)
-                        RowLayout {
-                            spacing: 8
-                            Layout.fillWidth: true
-
-                            Label {
-                                text: "CONNECTION FLOW"
-                                color: Theme.sideMutedText
-                                font.pixelSize: Theme.fontXs
-                                font.letterSpacing: 1.2
-                                font.bold: true
-                            }
-
-                            Rectangle {
-                                height: 18
-                                width: badgeLabel.implicitWidth + 14
-                                radius: 9
-                                color: {
-                                    var s = deviceController.connectionStatus
-                                    if (s === "Connected") return Theme.statusSuccessColor
-                                    if (s === "Disconnected") return Theme.statusErrorColor
-                                    return Theme.statusWarningColor
-                                }
-
-                                Label {
-                                    id: badgeLabel
-                                    anchors.centerIn: parent
-                                    text: deviceController.connectionStatus || "Disconnected"
-                                    color: "#111111"
-                                    font.pixelSize: Theme.font2xs
-                                    font.bold: true
-                                }
-                            }
-
-                            Item { Layout.fillWidth: true }
-                        }
-
-                        // Row 2: Status dot + descriptive text (replaces dotted trail)
-                        Row {
-                            spacing: 8
-                            Layout.fillWidth: true
-
-                            Rectangle {
-                                id: statusDot
-                                anchors.verticalCenter: parent.verticalCenter
-                                width: 8
-                                height: 8
-                                radius: 4
-                                color: deviceController.connectionStatus === "Connected"
-                                    ? Theme.statusSuccessColor : Theme.statusErrorColor
-
-                                SequentialAnimation on opacity {
-                                    running: deviceController.connectionStatus === "Connected"
-                                    loops: Animation.Infinite
-                                    NumberAnimation { to: 0.4; duration: 1200 }
-                                    NumberAnimation { to: 1.0; duration: 1200 }
-                                }
-                            }
-
-                            Label {
-                                anchors.verticalCenter: parent.verticalCenter
-                                text: {
-                                    if (deviceController.connectionStatus === "Connected")
-                                        return deviceController.selectedPort || "Connected"
-                                    if (deviceController.selectedPort)
-                                        return deviceController.selectedPort
-                                    return "No port selected"
-                                }
-                                color: Theme.bodyColor
-                                font.family: Theme.uiFontFamily
-                                font.pixelSize: Theme.fontXs
-                                elide: Text.ElideRight
-                            }
-                        }
-
-                        // Row 3: Mode chip — neutral gray tag
-                        Row {
-                            spacing: 6
-                            Layout.fillWidth: true
-
-                            Rectangle {
-                                anchors.verticalCenter: parent.verticalCenter
-                                width: modeChipLabel.implicitWidth + 12
-                                height: 18
-                                radius: 4
-                                color: Theme.fieldBackground
-                                border.color: Theme.sideBorder
-                                border.width: 1
-
-                                Label {
-                                    id: modeChipLabel
-                                    anchors.centerIn: parent
-                                    text: streamController.mode
-                                        ? streamController.mode.toUpperCase() : "REVIEW"
-                                    color: Theme.sideMutedText
-                                    font.family: Theme.uiFontFamily
-                                    font.pixelSize: Theme.font2xs
-                                    font.bold: true
-                                    font.letterSpacing: 0.8
-                                }
-                            }
-                        }
-                    }
                 }
 
                 // ── BOX 4: Utility Buttons ─────────────────────────────────
-                Rectangle {
+                UtilityFooter {
+                    id: utilFooter
                     Layout.fillWidth: true
-                    Layout.preferredHeight: Theme.sideFooterUtility
-                    radius: Theme.sidePanelRadius
-                    border.color: Theme.sideBorder
-                    border.width: 1
-                    color: Theme.sidePanelBackground
-
-                    RowLayout {
-                        anchors.fill: parent
-                        anchors.margins: 4
-                        spacing: 4
-
-                        Button {
-                            id: settingsBtn
-                            flat: true
-                            Layout.fillWidth: true
-                            Layout.fillHeight: true
-                            icon.source: "Tabs/icons/settings.svg"
-                            onClicked: settingsPopup.open()
-
-                            background: Rectangle {
-                                radius: 8
-                                color: settingsBtn.hovered
-                                    ? Theme.sideActiveBackground : "transparent"
-                            }
-
-                            contentItem: Row {
-                                spacing: 6
-                                anchors.centerIn: parent
-
-                                IconImage {
-                                    anchors.verticalCenter: parent.verticalCenter
-                                    width: 16
-                                    height: 16
-                                    source: "Tabs/icons/settings.svg"
-                                    sourceSize.width: 16
-                                    sourceSize.height: 16
-                                    color: Theme.headingColor
-                                    opacity: 0.75
-                                }
-
-                                Label {
-                                    anchors.verticalCenter: parent.verticalCenter
-                                    text: "SETTINGS"
-                                    color: Theme.headingColor
-                                    font.family: Theme.uiFontFamily
-                                    font.pixelSize: Theme.fontXs
-                                    font.bold: true
-                                    font.letterSpacing: 1.2
-                                    opacity: 0.8
-                                }
-                            }
-                        }
-
-                        Rectangle {
-                            width: 1
-                            height: 24
-                            color: Theme.sideBorder
-                        }
-
-                        Button {
-                            id: aboutBtn
-                            flat: true
-                            Layout.fillWidth: true
-                            Layout.fillHeight: true
-                            icon.source: "Tabs/icons/about.svg"
-                            onClicked: aboutDialog.open()
-
-                            background: Rectangle {
-                                radius: 8
-                                color: aboutBtn.hovered
-                                    ? Theme.sideActiveBackground : "transparent"
-                            }
-
-                            contentItem: Row {
-                                spacing: 6
-                                anchors.centerIn: parent
-
-                                IconImage {
-                                    anchors.verticalCenter: parent.verticalCenter
-                                    width: 16
-                                    height: 16
-                                    source: "Tabs/icons/about.svg"
-                                    sourceSize.width: 16
-                                    sourceSize.height: 16
-                                    color: Theme.headingColor
-                                    opacity: 0.75
-                                }
-
-                                Label {
-                                    anchors.verticalCenter: parent.verticalCenter
-                                    text: "ABOUT"
-                                    color: Theme.headingColor
-                                    font.family: Theme.uiFontFamily
-                                    font.pixelSize: Theme.fontXs
-                                    font.bold: true
-                                    font.letterSpacing: 1.2
-                                    opacity: 0.8
-                                }
-                            }
-                        }
-                    }
+                    settingsPopup: settingsPopup
+                    aboutDialog: aboutDialog
                 }
             }
         }
@@ -619,8 +633,6 @@ Rectangle {
             Layout.fillWidth: true
             Layout.fillHeight: true
             color: Theme.workspaceBackground
-            border.color: Theme.workspaceBorder
-            border.width: 1
 
             StackLayout {
                 anchors.fill: parent
@@ -632,11 +644,18 @@ Rectangle {
                     active: StackLayout.index === root.selectedTabIndex
                 }
                 Loader {
+                    id: dataTabLoader
                     source: "Tabs/DataTab.qml"
                     active: StackLayout.index === root.selectedTabIndex
                 }
                 Loader {
                     source: "Tabs/WaferMapTab.qml"
+                    // TODO P3.1: append `&& licenseModel.licenses.length > 0`
+                    //   so the tab never instantiates while locked. See plan §3.1.
+                    active: StackLayout.index === root.selectedTabIndex
+                }
+                Loader {
+                    source: "Tabs/GraphTab.qml"
                     active: StackLayout.index === root.selectedTabIndex
                 }
             }

src/pygui/ISC/Tabs/DataTab.qml

@@ -1,185 +1,373 @@
 import QtQuick
 import QtQuick.Controls
+import QtQuick.Controls.impl
 import QtQuick.Layouts
 import ISC
+import ISC.Tabs.components
+import ISC.Wafer
 
-// ===== Data Tab =====
-// Displays parsed temperature data in a scrollable table.
-// Column 0 = Row index, remaining columns = Sensor1, Sensor2, ...
+// ===== Data Tab (Compare Content Only) =====
+// Per docs/design/navigation-mock.html: the Data tab shows only the Compare
+// Runs content — the raw CSV table ("Inspect Table" mode in earlier drafts)
+// is intentionally not displayed in the application.
+// Layout: left column = aligned-curves chart with alignment scrubber + wafer
+// overlap map; right side panel = run selection dropdowns, overlap settings,
+// and DTW readout cards.
 Item {
     id: root
     anchors.fill: parent
 
-    readonly property int rowCount: deviceController.dataRowCount
+    // Properties for DTW Comparison
+    property int activeBox: 1 // 1 for Reference (Run A), 2 for Session (Run B), 0 for inactive
+    property string compareFileA: ""
+    property string compareFileB: ""
+    property bool useMasterFile: false // Run A comes from settingsModel.masters[runBWaferType] instead of manual selection
 
-    // Re-layout columns whenever the model is reset
+    function waferTypeForFile(path) {
+        if (!path) return ""
+        // A file registered as a master carries that slot's family — this is
+        // the only way a live recording gets a family (its filename/metadata
+        // don't encode one reliably).
+        for (var fam in settingsModel.masters)
+            if (settingsModel.masters[fam] === path) return fam.toUpperCase()
+        var rows = file_browser.files
+        for (var i = 0; i < rows.length; i++) {
+            if (rows[i].fileName === path) {
+                if (rows[i].isRecording) return (rows[i].masterType || "").toUpperCase()
+                return (rows[i].waferType || "").toUpperCase()
+            }
+        }
+        var base = path.split("/").pop()
+        if (base.toLowerCase().indexOf("live_") === 0) return ""
+        return base ? base.charAt(0).toUpperCase() : ""
+    }
+
+    // Master file must match Run B's wafer family — looking it up by that
+    // family is itself the comparability gate (a mismatched-family master
+    // simply won't exist under this key).
+    readonly property string runBWaferType: root.waferTypeForFile(root.compareFileB)
+    readonly property string masterFileForRunB: root.runBWaferType !== "" ? (settingsModel.masters[root.runBWaferType] || "") : ""
+    readonly property string runAWaferType: root.useMasterFile ? root.runBWaferType : root.waferTypeForFile(root.compareFileA)
+    // Family gate: both runs must resolve to the same wafer family. An empty
+    // family means an unassigned live recording — comparable only after it is
+    // registered as a master file (Settings → Master Files).
+    readonly property string familyGateError: {
+        var fileA = root.useMasterFile ? root.masterFileForRunB : root.compareFileA
+        if (fileA === "" || root.compareFileB === "") return ""
+        if (root.runAWaferType === "" || root.runBWaferType === "")
+            return "Recording has no wafer family — register it as a master file (Settings → Master Files)"
+        if (root.runAWaferType !== root.runBWaferType)
+            return "Wafer Family Mismatch: " + root.runAWaferType + " vs " + root.runBWaferType
+        return ""
+    }
+    property real warpingDistance: -1
+    property int frameOffset: 0
+    property real frameOffsetSeconds: 0
+    property real maxSensorDeviation: -1
+    property bool comparing: false
+    property var trendDataA: []
+    property var trendDataB: []
+    property var timeDataA: []
+    property var timeDataB: []
+    property int frameCountA: 0
+    property int frameCountB: 0
+    property string errorMessage: ""
+    property string mismatchMessage: ""
+
+    // Wafer overlap properties
+    property var compareSensorLayout: []
+    property var compareSensorDiff: []
+    property string compareWaferShape: "round"
+    property real compareWaferSize: 300.0
+
+    readonly property bool hasSeries: trendDataA.length > 1 && trendDataB.length > 1
+    readonly property int seriesLen: Math.max(trendDataA.length, trendDataB.length)
+
+    function diffBands(diffs) {
+        return diffs.map(d => d > 1.0 ? "high" : d < -1.0 ? "low" : "in_range")
+    }
+
+    function shortName(path) {
+        return path ? path.split("/").pop() : ""
+    }
+
+    function scrubTimeLabel(idx) {
+        var t = idx < root.timeDataA.length ? root.timeDataA[idx]
+            : (idx < root.timeDataB.length ? root.timeDataB[idx] : null)
+        return t !== null ? " (" + t.toFixed(1) + "s)" : ""
+    }
+
+    function formatMinutes(secondsValue) {
+        var mins = Math.floor(secondsValue / 60)
+        var secs = secondsValue % 60
+        return mins + ":" + (secs < 10 ? "0" : "") + secs.toFixed(1)
+    }
+
+    function frameForTime(t) {
+        var times = root.timeDataA.length > 0 ? root.timeDataA : root.timeDataB
+        if (times.length === 0) return 0
+        var closestIdx = 0
+        var minDiff = Math.abs(times[0] - t)
+        for (var i = 1; i < times.length; i++) {
+            var diff = Math.abs(times[i] - t)
+            if (diff < minDiff) {
+                minDiff = diff
+                closestIdx = i
+            }
+        }
+        return closestIdx
+    }
+
+    function clearResults() {
+        root.warpingDistance = -1
+        root.frameOffset = 0
+        root.frameOffsetSeconds = 0
+        root.maxSensorDeviation = -1
+        root.trendDataA = []
+        root.trendDataB = []
+        root.timeDataA = []
+        root.timeDataB = []
+        root.frameCountA = 0
+        root.frameCountB = 0
+        root.compareSensorLayout = []
+        root.compareSensorDiff = []
+        root.errorMessage = ""
+        root.mismatchMessage = ""
+        mismatchHideTimer.stop()
+    }
+
+    function resetComparison() {
+        root.compareFileA = ""
+        root.compareFileB = ""
+        root.useMasterFile = false
+        root.comparing = false
+        root.activeBox = 1
+        clearResults()
+    }
+
+    Component.onCompleted: file_browser.refreshFiles()
+
+    Timer {
+        id: mismatchHideTimer
+        interval: 6000
+        onTriggered: root.mismatchMessage = ""
+    }
+
+    // Clicking a file in the left rail's browser populates the armed run slot
     Connections {
-        target: deviceController
-        function onParsedDataReady(result) {
+        target: streamController
+        function onLoadedFileChanged() {
+            if (streamController.loadedFile && root.activeBox > 0) {
+                if (root.activeBox === 1) {
+                    root.compareFileA = streamController.loadedFile
+                    root.activeBox = 2 // Auto-advance to box 2
+                } else if (root.activeBox === 2) {
+                    root.compareFileB = streamController.loadedFile
+                    root.activeBox = 0 // Finished selecting
+                }
+            }
+        }
+        function onComparisonResult(result) {
+            root.comparing = false
             if (result && result.success) {
-                dataTable.forceLayout();
+                root.warpingDistance = result.distance
+                root.frameOffset = result.frame_offset !== undefined ? result.frame_offset : 0
+                root.frameOffsetSeconds = result.frame_offset_seconds !== undefined ? result.frame_offset_seconds : 0
+                root.maxSensorDeviation = result.max_sensor_deviation !== undefined ? result.max_sensor_deviation : -1
+                root.trendDataA = result.series_a || []
+                root.trendDataB = result.series_b || []
+                root.timeDataA = result.time_a || []
+                root.timeDataB = result.time_b || []
+                root.frameCountA = result.frame_count_a || 0
+                root.frameCountB = result.frame_count_b || 0
+                root.compareSensorLayout = result.sensor_layout || []
+                root.compareSensorDiff = result.sensor_diff || []
+                root.compareWaferShape = result.wafer_shape || "round"
+                root.compareWaferSize = result.wafer_size || 300.0
+                root.errorMessage = ""
+                chartCard.frameIndex = Math.floor(root.seriesLen / 2)
+                chartCard.focusScrubber()
+                if (root.frameCountA !== root.frameCountB) {
+                    var timeA = root.timeDataA.length > 0 ? root.timeDataA[root.timeDataA.length - 1] : 0
+                    var timeB = root.timeDataB.length > 0 ? root.timeDataB[root.timeDataB.length - 1] : 0
+                    root.mismatchMessage = "Run A: " + root.frameCountA + " frames (" + timeA.toFixed(1) + "s) · "
+                        + "Run B: " + root.frameCountB + " frames (" + timeB.toFixed(1) + "s). "
+                        + "Deviation beyond the shorter run shows as \"none\"."
+                    mismatchHideTimer.restart()
+                } else {
+                    root.mismatchMessage = ""
+                    mismatchHideTimer.stop()
+                }
+            } else {
+                root.clearResults()
+                root.errorMessage = (result && result.error) ? result.error : "Comparison failed"
             }
         }
     }
 
-    // ===== Empty State =====
-    Column {
-        anchors.centerIn: parent
-        spacing: 16
-        visible: root.rowCount === 0
-
-        Label {
-            text: "No Data"
-            font.pixelSize: Theme.font2xl
-            font.bold: true
-            color: Theme.headingColor
-            anchors.horizontalCenter: parent.horizontalCenter
-        }
-
-        Label {
-            text: "Read and parse wafer data to see temperature readings here."
-            font.pixelSize: Theme.fontMd
-            color: Theme.bodyColor
-            anchors.horizontalCenter: parent.horizontalCenter
-            wrapMode: Text.WordWrap
-        }
-    }
-
-    // ===== Data Table =====
+    // ── Main Layout ───────────────────────────────────────────────
     ColumnLayout {
         anchors.fill: parent
         anchors.margins: Theme.panelPadding
         spacing: Theme.rightPaneGap
-        visible: root.rowCount > 0
 
-        // --- Header row ---
-        RowLayout {
-            Layout.fillWidth: true
-            spacing: Theme.rightPaneGap
 
-            Label {
-                text: "Temperature Data"
-                font.pixelSize: Theme.fontXl
-                font.bold: true
-                color: Theme.headingColor
-            }
 
-            Item {
-                Layout.fillWidth: true
-            }
-
-            Label {
-                text: deviceController.dataRowCount + " rows × " + deviceController.dataColCount + " sensors"
-                font.pixelSize: Theme.fontSm
-                color: Theme.bodyColor
-            }
-        }
-
-        // --- Toolbar ---
-        RowLayout {
-            Layout.fillWidth: true
-            spacing: 8
-
-            Button {
-                text: "Open in Excel"
-                icon.source: "icons/excel.svg"
-                icon.color: Theme.headingColor
-                onClicked: deviceController.openCsvFile()
-            }
-
-            Button {
-                text: "Compare"
-                onClicked: compareDialog.open()
-            }
-
-            Button {
-                text: "Split"
-                onClicked: splitDialog.open()
-            }
-
-            Item {
-                Layout.fillWidth: true
-            }
-        }
-        // --- Table container ---
+        // ── Error Banner ───────────────────────────────────────────
         Rectangle {
             Layout.fillWidth: true
-            Layout.fillHeight: true
-            color: Theme.panelBackground
-            border.color: Theme.cardBorder
-            border.width: Theme.borderThin
+            Layout.preferredHeight: errorRow.implicitHeight + 16
+            visible: root.errorMessage !== ""
+            color: Theme.errorSurface
+            border.color: Theme.statusErrorColor
+            border.width: 1
             radius: Theme.radiusSm
-            clip: true
 
-            ColumnLayout {
+            RowLayout {
+                id: errorRow
                 anchors.fill: parent
-                anchors.margins: 1
-                spacing: 0
+                anchors.margins: 8
+                spacing: 8
 
-                // Column header strip
-                HorizontalHeaderView {
-                    id: headerView
-                    Layout.fillWidth: true
-                    syncView: dataTable
-                    clip: true
-
-                    delegate: Rectangle {
-                        implicitHeight: 28
-                        color: Theme.cardBackground
-                        border.color: Theme.cardBorder
-                        border.width: 1
-
-                        Text {
-                            anchors.centerIn: parent
-                            // 'display' is the Qt.DisplayRole value from headerData()
-                            text: display !== undefined ? display : ""
-                            color: Theme.headingColor
-                            font.pixelSize: Theme.fontXs
-                            font.bold: true
-                            elide: Text.ElideRight
-                        }
-                    }
+                IconImage {
+                    source: "icons/triangle-alert.svg"
+                    width: 16; height: 16
+                    sourceSize.width: 16
+                    sourceSize.height: 16
+                    color: Theme.errorTextSoft
+                    Layout.alignment: Qt.AlignTop
                 }
 
-                // Data rows
-                TableView {
-                    id: dataTable
+                Label {
+                    id: errorLabel
+                    text: root.errorMessage
+                    color: Theme.errorTextSoft
+                    font.pixelSize: Theme.fontSm
+                    wrapMode: Text.WordWrap
+                    Layout.fillWidth: true
+                }
+            }
+        }
+
+        // ── Body: main column | side panel ─────────────────────────
+        RowLayout {
+            Layout.fillWidth: true
+            Layout.fillHeight: true
+            spacing: 16
+
+            // --- Left Column: chart + scrubber, wafer overlap map ---
+            ColumnLayout {
+                Layout.fillWidth: true
+                Layout.fillHeight: true
+                Layout.minimumWidth: 350
+                spacing: 12
+
+                // Wafer Map Overlap View card
+                OverlapMapCard {
                     Layout.fillWidth: true
                     Layout.fillHeight: true
-                    model: deviceController.dataModel
-                    clip: true
-                    reuseItems: true
+                    Layout.minimumHeight: 220
+                    sensorLayout: root.compareSensorLayout
+                    diffValues: streamController.getSensorDiffAt(Math.round(chartCard.frameIndex))
+                    diffBands: root.diffBands
+                    waferShape: root.compareWaferShape
+                    waferSize: root.compareWaferSize
+                    overlapEnabled: sidePanel.overlapEnabled
+                    blendAmount: sidePanel.blendAmount
+                }
 
-                    columnWidthProvider: function (col) {
-                        if (col === 0)
-                            return 52;   // row index column
-                        const sensorCols = Math.max(1, dataTable.columns - 1);
-                        const available = dataTable.width - 52;
-                        return Math.max(52, Math.min(90, available / sensorCols));
-                    }
+                // Chart card with alignment scrubber
+                ComparisonChartCard {
+                    id: chartCard
+                    Layout.fillWidth: true
+                    trendDataA: root.trendDataA
+                    trendDataB: root.trendDataB
+                    seriesLen: root.seriesLen
+                    hasSeries: root.hasSeries
+                    comparing: root.comparing
+                }
+}
 
-                    rowHeightProvider: function () {
-                        return 24;
-                    }
+            // --- Right Column: run selection, overlap settings, readout ---
+            ComparisonSidePanel {
+                id: sidePanel
+                Layout.fillWidth: false                
+                Layout.preferredWidth: Theme.rightRailWidth
+                Layout.minimumWidth: Theme.rightRailWidth
+                Layout.maximumWidth: Theme.rightRailWidth
+                Layout.fillHeight: true
+                warpingDistance: root.warpingDistance
+                frameOffset: root.frameOffset
+                frameOffsetSeconds: root.frameOffsetSeconds
+                maxSensorDeviation: root.maxSensorDeviation
+                seriesLen: root.seriesLen
+                hasSeries: root.hasSeries
+                trendDataA: root.trendDataA
+                trendDataB: root.trendDataB
+                timeDataA: root.timeDataA
+                timeDataB: root.timeDataB
+                frameForTime: root.frameForTime
+                frameIndex: chartCard.frameIndex
+                onFrameIndexRequested: (idx) => chartCard.frameIndex = idx
+                onScrubberFocusRequested: chartCard.focusScrubber()
+            }
+        }
+    }
 
-                    delegate: Rectangle {
-                        color: row % 2 === 0 ? Theme.panelBackground : Theme.cardBackground
+    // ── Frame Mismatch Banner (amber, floats over content, auto-hides) ──
+    Rectangle {
+        id: mismatchBanner
+        visible: root.mismatchMessage !== ""
+        z: 100
+        anchors.top: parent.top
+        anchors.horizontalCenter: parent.horizontalCenter
+        anchors.topMargin: 12
+        width: Math.min(parent.width - 48, 640)
+        height: mismatchRow.implicitHeight + 16
+        color: Theme.cardBackground
+        border.color: Theme.statusWarningColor
+        border.width: 1
+        radius: Theme.radiusSm
 
-                        Text {
-                            anchors.centerIn: parent
-                            text: display !== undefined ? display : ""
-                            color: Theme.bodyColor
-                            font.pixelSize: Theme.fontXs
-                            elide: Text.ElideRight
-                        }
-                    }
+        RowLayout {
+            id: mismatchRow
+            anchors.fill: parent
+            anchors.margins: 8
+            spacing: 8
 
-                    ScrollBar.horizontal: ScrollBar {
-                        policy: ScrollBar.AsNeeded
-                    }
-                    ScrollBar.vertical: ScrollBar {
-                        policy: ScrollBar.AsNeeded
-                    }
+            IconImage {
+                source: "icons/triangle-alert.svg"
+                width: 16; height: 16
+                sourceSize.width: 16
+                sourceSize.height: 16
+                color: Theme.statusWarningColor
+                Layout.alignment: Qt.AlignTop
+            }
+
+            Label {
+                text: root.mismatchMessage
+                color: Theme.statusWarningColor
+                font.pixelSize: Theme.fontSm
+                wrapMode: Text.WordWrap
+                Layout.fillWidth: true
+            }
+
+            Button {
+                flat: true
+                implicitWidth: 24
+                implicitHeight: 24
+                Layout.alignment: Qt.AlignTop
+                onClicked: {
+                    root.mismatchMessage = ""
+                    mismatchHideTimer.stop()
+                }
+                background: Rectangle { color: "transparent" }
+                contentItem: Label {
+                    text: "✕"
+                    color: Theme.statusWarningColor
+                    font.pixelSize: Theme.fontXs
+                    horizontalAlignment: Text.AlignHCenter
+                    verticalAlignment: Text.AlignVCenter
                 }
             }
         }

src/pygui/ISC/Tabs/GraphTab.qml

@@ -1,222 +1,49 @@
 import QtQuick
-import QtQuick.Controls
 import QtQuick.Layouts
 import ISC
-import ISC.Wafer
+import ISC.Tabs.components
 
 // ===== Graph Tab =====
-// Displays sensor temperature line charts using GraphQuickItem.
-// Gets data from deviceController.getChartData() (parsed CSV, batch read)
-// or from streamController.trendData (live streaming trend).
+// Whole-run multi-sensor line chart (C# parity: tabGraph/chartData). Static
+// snapshot recomputed whenever a file is loaded — not live-updating during
+// a stream. RunChart adds wheel zoom, drag pan, and a visible-range
+// min/max/avg strip. See specs/plans/2026-07-10-graph-tab.md and
+// docs/adr/0003-pyqtgraph-for-multi-sensor-charts.md.
 Item {
     id: root
     anchors.fill: parent
 
-    property var _chartData: null   // cached result from getChartData()
-
-    ColumnLayout {
-        anchors.fill: parent
-        anchors.margins: Theme.panelPadding
-        spacing: Theme.rightPaneGap
-
-        // ── Toolbar ───────────────────────────────────────────────────────────
-        RowLayout {
-            Layout.fillWidth: true
-            spacing: 10
-
-            Label {
-                text: "Line Chart"
-                color: Theme.headingColor
-                font.pixelSize: Theme.fontSm
-                font.bold: true
-                Layout.alignment: Qt.AlignVCenter
-            }
-
-            Item {
-                Layout.fillWidth: true
-            }
-
-            // Refresh button — pulls data from deviceController
-            Button {
-                id: refreshBtn
-                text: "REFRESH"
-                font.pixelSize: Theme.fontXs
-                font.weight: Font.Medium
-                implicitHeight: 26
-                implicitWidth: 72
-                hoverEnabled: true
-                background: Rectangle {
-                    color: parent.hovered ? Theme.buttonNeutralHover : Theme.buttonNeutralBackground
-                    border.color: Theme.cardBorder
-                    border.width: 1
-                    radius: Theme.radiusSm
-                }
-                contentItem: Text {
-                    text: parent.text
-                    color: Theme.headingColor
-                    font: parent.font
-                    horizontalAlignment: Text.AlignHCenter
-                    verticalAlignment: Text.AlignVCenter
-                }
-                onClicked: reloadData()
-            }
-        }
-
-        // ── Mode selector (Trend / Full chart) ─────────────────────────────
-        RowLayout {
-            Layout.fillWidth: true
-            spacing: 8
-
-            Label {
-                text: "Source:"
-                color: Theme.bodyColor
-                font.pixelSize: Theme.fontXs
-                Layout.alignment: Qt.AlignVCenter
-            }
-
-            ComboBox {
-                id: sourceSelector
-                model: ["Parsed Data", "Live Trend"]
-                currentIndex: 0
-                implicitHeight: 26
-                font.pixelSize: Theme.fontXs
-                background: Rectangle {
-                    color: Theme.fieldBackground
-                    border.color: Theme.fieldBorder
-                    border.width: 1
-                    radius: Theme.radiusSm
-                }
-                contentItem: Text {
-                    text: sourceSelector.displayText
-                    color: Theme.fieldText
-                    font: sourceSelector.font
-                    horizontalAlignment: Text.AlignLeft
-                    verticalAlignment: Text.AlignVCenter
-                    leftPadding: 8
-                }
-                onCurrentIndexChanged: reloadData()
-            }
-
-            Item {
-                Layout.fillWidth: true
-            }
-
-            Label {
-                id: statusLabel
-                text: "Ready"
-                color: Theme.bodyColor
-                font.pixelSize: Theme.fontXs
-                font.italic: true
-                Layout.alignment: Qt.AlignVCenter
-            }
-        }
-
-        // ── Chart Area ─────────────────────────────────────────────────────────
-        Rectangle {
-            Layout.fillWidth: true
-            Layout.fillHeight: true
-            color: Theme.cardBackground
-            border.color: Theme.cardBorder
-            border.width: 1
-            radius: Theme.radiusMd
-            clip: true
-
-            GraphQuickItem {
-                id: graph
-                anchors.fill: parent
-                anchors.margins: 2
-                backgroundColor: Theme.cardBackground
-                gridColor: Theme.softBorder
-                axisColor: Theme.bodyColor
-                textColor: Theme.headingColor
-                seriesColors: [Theme.sensorLow, Theme.sensorHigh, Theme.sensorInRange, "#FFA726", "#AB47BC", "#00BCD4"]
-                showLegend: true
-            }
-        }
-    }
-
-    // ── Data Loading ────────────────────────────────────────────────────────────
-
-    function reloadData() {
-        if (sourceSelector.currentIndex === 0) {
-            // Parsed data from DeviceController
-            loadParsedData();
-        } else {
-            // Live trend from SessionController
-            loadLiveTrend();
-        }
-    }
-
-    function loadParsedData() {
-        statusLabel.text = "Loading...";
-        var result = deviceController.getChartData();
-        if (!result || !result.success) {
-            graph.seriesData = [];
-            graph.sensorNames = [];
-            graph.title = "Sensor Temperature Over Time";
-            statusLabel.text = "No data — read a wafer first";
-            return;
-        }
-
-        graph.seriesData = result.series || [];
-        graph.sensorNames = result.sensor_names || [];
-        graph.title = "Sensor Temperature Over Time";
-        statusLabel.text = (result.series ? result.series.length : 0) + " sensors loaded";
-    }
-
-    function loadLiveTrend() {
-        // Live trend: connects to streamController.trendData
-        // The trend data comes as a JSON array of per-frame averages
-        statusLabel.text = "Connecting to live trend...";
-        // We need at least one data point
-        if (streamController.stats && streamController.stats.avg !== undefined) {
-            // Build a single-series graph from the trend buffer
-            // For now show a placeholder — the trendData signal handles updates
-            graph.title = "Live Average Temperature";
-            graph.yLabel = "Avg Temperature (°C)";
-            graph.xLabel = "Time (s)";
-            statusLabel.text = "Live trend — waiting for data...";
-        } else {
-            statusLabel.text = "No live data — start a stream on the Wafer Map tab";
-        }
-    }
-
-    // ── Connections ─────────────────────────────────────────────────────────────
-
-    Connections {
-        target: deviceController
-        function onParsedDataReady(result) {
-            if (sourceSelector.currentIndex === 0) {
-                root.reloadData();
-            }
+    function refresh() {
+        if (!streamController.loadedFile) {
+            chart.seriesData = []
+            chart.sensorNames = []
+            return
         }
+        chart.sensorNames = streamController.graphSensorNames
+            ? streamController.graphSensorNames.split(",") : []
+        chart.seriesData = JSON.parse(streamController.graphSeriesJson || "[]")
     }
 
     Connections {
         target: streamController
-        function onTrendData(avgsJson) {
-            if (sourceSelector.currentIndex === 1) {
-                try {
-                    var avgs = JSON.parse(avgsJson);
-                    if (avgs && avgs.length > 0) {
-                        graph.seriesData = [avgs];
-                        graph.sensorNames = ["Average"];
-                        graph.title = "Live Average Temperature";
-                        graph.yLabel = "Avg Temperature (°C)";
-                        graph.xLabel = "Frame";
-                        statusLabel.text = "Live: " + avgs.length + " data points";
-                    }
-                } catch (e) {
-                    // ignore parse errors
-                }
-            }
-        }
+        function onLoadedFileChanged() { root.refresh() }
     }
 
-    // On startup, try to load parsed data if available
-    Component.onCompleted: {
-        if (deviceController.dataRowCount > 0) {
-            reloadData();
+    Component.onCompleted: root.refresh()
+
+    Rectangle {
+        anchors.fill: parent
+        anchors.margins: Theme.panelPadding
+        color: Theme.cardBackground
+        border.color: Theme.cardBorder
+        border.width: 1
+        radius: Theme.radiusMd
+
+        RunChart {
+            id: chart
+            anchors.fill: parent
+            anchors.margins: 8
+            title: "Sensor Temperature Over Time"
         }
     }
 }

src/pygui/ISC/Tabs/SettingsTab.qml

@@ -1,8 +1,10 @@
 import QtQuick
 import QtQuick.Controls
+import QtQuick.Controls.impl
 import QtQuick.Layouts
 import QtQuick.Dialogs
 import ISC
+import ISC.Tabs.components
 
 Item {
     id: root
@@ -123,19 +125,17 @@ Item {
                 ColorAnimation { duration: Theme.durationFast }
             }
 
-            Text {
+            IconImage {
                 anchors.centerIn: parent
-                text: "✓"
-                font.pixelSize: Theme.fontMd
-                font.bold: true
+                source: "icons/check.svg"
+                width: 12; height: 12
+                sourceSize.width: 12
+                sourceSize.height: 12
                 color: Theme.panelBackground
                 opacity: toggle.checked ? 1.0 : 0.0
                 Behavior on opacity {
                     NumberAnimation { duration: Theme.durationFast }
                 }
-                // Small nudge to center the checkmark perfectly
-                verticalAlignment: Text.AlignVCenter
-                horizontalAlignment: Text.AlignHCenter
             }
         }
 
@@ -366,7 +366,7 @@ Item {
                                 width: 22
                                 height: 22
                                 radius: height / 2
-                                color: "white"
+                                color: Theme.toggleThumb
                                 anchors.verticalCenter: parent.verticalCenter
                                 x: Theme.isDarkMode ? parent.width - width - 3 : 3
 
@@ -452,12 +452,9 @@ Item {
                 }
             }
 
-            Label {
+            Row {
                 anchors.centerIn: parent
-                text: "↓ Scroll for more"
-                font.pixelSize: Theme.fontSm
-                font.bold: true
-                color: Theme.bodyColor
+                spacing: 4
                 opacity: (settingsScroll.ScrollBar.vertical.position <= 0 && settingsScroll.contentHeight > settingsScroll.height) ? (scrollHintTimer.running ? 1 : 0) : 0
 
                 Behavior on opacity {
@@ -465,6 +462,22 @@ Item {
                         duration: 400
                     }
                 }
+
+                IconImage {
+                    anchors.verticalCenter: parent.verticalCenter
+                    source: "icons/chevron-down.svg"
+                    width: 14; height: 14
+                    sourceSize.width: 14
+                    sourceSize.height: 14
+                    color: Theme.bodyColor
+                }
+                Label {
+                    anchors.verticalCenter: parent.verticalCenter
+                    text: "Scroll for more"
+                    font.pixelSize: Theme.fontSm
+                    font.bold: true
+                    color: Theme.bodyColor
+                }
             }
         }
     }

src/pygui/ISC/Tabs/StatusTab.qml

@@ -1,6 +1,7 @@
 import QtQuick
 import QtQuick.Layouts
 import QtQuick.Controls
+import QtQuick.Controls.impl
 import QtQuick.Dialogs
 import ISC
 
@@ -29,52 +30,61 @@ ColumnLayout {
         radius: Theme.radiusSm
 
         ColumnLayout {
-            anchors.centerIn: parent
+            anchors.fill: parent
+            anchors.margins: Theme.panelPadding
             spacing: 4
+            Text {
+                id: labelText
+                color: Theme.sideMutedText
+                font.pixelSize: Theme.fontSm
+                font.bold: true
+                font.letterSpacing: 1.5
+                font.family: Theme.uiFontFamily
+            }
             Text {
                 id: valueText
                 color: active ? Theme.headingColor : Theme.sideMutedText
                 font.pixelSize: valSize
                 font.weight: Font.Bold
                 font.family: Theme.uiFontFamily
-                Layout.alignment: Qt.AlignHCenter
-            }
-            Text {
-                id: labelText
-                color: Theme.sideMutedText
-                font.pixelSize: Theme.fontXs
-                font.weight: Font.Medium
-                font.letterSpacing: 1.2
-                font.family: Theme.uiFontFamily
-                Layout.alignment: Qt.AlignHCenter
+                Layout.fillHeight: true
+                Layout.fillWidth: true
+                horizontalAlignment: Text.AlignHCenter
+                verticalAlignment: Text.AlignVCenter
+                fontSizeMode: Text.HorizontalFit
+                minimumPixelSize: Theme.fontMd
             }
         }
     }
 
+    // Stacked stat block: small label over big value, centered in its grid
+    // quadrant so the card's height is used instead of leaving dead space.
     component GridCell : ColumnLayout {
         property alias label: labelText.text
         property alias value: valueText.text
-        property bool isRight: false
         property bool active: root.waferDetected
 
-        spacing: 1
-        Layout.alignment: isRight ? Qt.AlignRight : Qt.AlignLeft
+        spacing: 2
+        Layout.fillWidth: true
+        Layout.fillHeight: true
 
+        Item { Layout.fillHeight: true }
         Text {
             id: labelText
             color: Theme.sideMutedText
             font.pixelSize: Theme.fontXs
             font.family: Theme.uiFontFamily
-            Layout.alignment: isRight ? Qt.AlignRight : Qt.AlignLeft
+            Layout.fillWidth: true
+            elide: Text.ElideRight
         }
         Text {
             id: valueText
             color: active ? Theme.headingColor : Theme.sideMutedText
-            font.pixelSize: Theme.fontMd
+            font.pixelSize: Theme.fontXl
             font.weight: Font.Bold
             font.family: Theme.uiFontFamily
-            Layout.alignment: isRight ? Qt.AlignRight : Qt.AlignLeft
         }
+        Item { Layout.fillHeight: true }
     }
 
     // ── Aliases for external wiring ──
@@ -112,21 +122,75 @@ ColumnLayout {
         id: saveDirDialog
         title: "Choose a folder to save."
         onAccepted: {
-            deviceController.setSaveDataDir(root.cleanFolderUrl(selectedFolder));
+            var dir = root.cleanFolderUrl(selectedFolder);
+            deviceController.setSaveDataDir(dir);
+            file_browser.setCurrentDirectory(dir);
             root.parseAndSavePendingRead();
         }
     }
 
-    // ═══════════════════════════════════════════════════════════════════════
-    //  ROW 1: Connection Status (100%)
-    // ═══════════════════════════════════════════════════════════════════════
-    RowLayout {
-        Layout.fillWidth: true
-        Layout.preferredHeight: 90
-        Layout.maximumHeight: 90
-        spacing: 8
+    // Directory-only picker for the DIRECTORY card button — sets the save dir
+    // without kicking off a parse/save of pending read data.
+    FolderDialog {
+        id: dirOnlyDialog
+        title: "Choose a folder to save Data"
+        onAccepted: {
+            var dir = root.cleanFolderUrl(selectedFolder);
+            deviceController.setSaveDataDir(dir);
+            file_browser.setCurrentDirectory(dir);
+        }
+    }
 
+    // Post-read metadata editor (C# parity: EditCSVMetadataDialog after read).
+    // Cancel keeps the CSV, skips the sidecar — matching C# behavior loosely.
+    Dialog {
+        id: editCsvDialog
+        parent: Overlay.overlay
+        modal: true
+        title: "Edit CSV Metadata"
+        width: 460
+        anchors.centerIn: parent
+        standardButtons: Dialog.Save | Dialog.Cancel
+        onAccepted: file_browser.saveMetadata(root.csvPath, metaWafer.text, metaDate.text, metaChamber.text, metaNotes.text, false, "")
+
+        ColumnLayout {
+            anchors.fill: parent
+            spacing: 6
+
+            Text {
+                text: root.csvPath.split("/").pop()
+                color: Theme.sideMutedText
+                font.pixelSize: Theme.fontXs
+                elide: Text.ElideMiddle
+                Layout.fillWidth: true
+            }
+            Label { text: "Wafer" }
+            TextField { id: metaWafer; Layout.fillWidth: true }
+            Label { text: "Date" }
+            TextField { id: metaDate; Layout.fillWidth: true }
+            Label { text: "Chamber" }
+            TextField { id: metaChamber; Layout.fillWidth: true }
+            Label { text: "Notes" }
+            TextField { id: metaNotes; Layout.fillWidth: true }
+        }
+    }
+
+    // ═══════════════════════════════════════════════════════════════════════
+    //  ROWS 1-2 (3-column bento):
+    //    [Connection Status] [Total Runtime  ] [Wafer & Sensor]
+    //    [Directory (span 2)                 ] [   (rowspan)  ]
+    // ═══════════════════════════════════════════════════════════════════════
+    GridLayout {
+        Layout.fillWidth: true
+        Layout.preferredHeight: 188
+        Layout.maximumHeight: 188
+        columns: 3
+        rowSpacing: 8
+        columnSpacing: 8
+
+        // ── Connection Status: two cells wide, top-left ──
         Rectangle {
+            Layout.columnSpan: 2
             Layout.fillWidth: true
             Layout.fillHeight: true
             color: Theme.cardBackground
@@ -135,43 +199,24 @@ ColumnLayout {
             radius: Theme.radiusSm
 
             ColumnLayout {
-                id: connStatusCol
-                anchors.left: parent.left
-                anchors.right: parent.right
-                anchors.verticalCenter: parent.verticalCenter
-                anchors.leftMargin: Theme.panelPadding
-                anchors.rightMargin: Theme.panelPadding
-                spacing: 8
+                anchors.fill: parent
+                anchors.margins: Theme.panelPadding
+                spacing: 6
 
                 Text {
                     text: "CONNECTION STATUS"
                     color: Theme.sideMutedText
-                    font.pixelSize: Theme.fontXs
-                    font.weight: Font.Medium
-                    font.letterSpacing: 1.2
+                    font.pixelSize: Theme.fontSm
+                    font.bold: true
+                    font.letterSpacing: 1.5
                     font.family: Theme.uiFontFamily
                 }
 
+                Item { Layout.fillHeight: true }
+
                 RowLayout {
                     Layout.fillWidth: true
-                    spacing: 0
-
-                    ColumnLayout {
-                        spacing: 1
-                        Text {
-                            text: "HOST PC"
-                            color: Theme.sideMutedText
-                            font.pixelSize: Theme.fontXs
-                            font.family: Theme.uiFontFamily
-                        }
-                        Text {
-                            text: "localhost"
-                            color: Theme.headingColor
-                            font.pixelSize: Theme.fontMd
-                            font.weight: Font.Bold
-                            font.family: Theme.uiFontFamily
-                        }
-                    }
+                    spacing: 8
 
                     Item {
                         Layout.fillWidth: true
@@ -209,7 +254,7 @@ ColumnLayout {
                                     id: statusPillText
                                     anchors.centerIn: parent
                                     text: root.isConnected ? "ACTIVE" : (root.isBusy ? deviceController.connectionStatus.replace("...", "").toUpperCase() : "INACTIVE")
-                                    color: "#111111"
+                                    color: Theme.statusBadgeText
                                     font.pixelSize: Theme.fontXs
                                     font.weight: Font.Bold
                                     font.family: Theme.uiFontFamily
@@ -236,218 +281,204 @@ ColumnLayout {
                         }
                     }
 
-                    ColumnLayout {
-                        spacing: 1
-                        Text {
-                            text: "COM PORT"
-                            color: Theme.sideMutedText
-                            font.pixelSize: Theme.fontXs
-                            font.family: Theme.uiFontFamily
-                            Layout.alignment: Qt.AlignRight
-                        }
-                        Text {
-                            text: root.portName
-                            color: root.isConnected ? Theme.statusSuccessColor : Theme.headingColor
-                            font.pixelSize: Theme.fontMd
-                            font.weight: Font.Bold
-                            font.family: Theme.uiFontFamily
-                            Layout.alignment: Qt.AlignRight
-                        }
+                    Text {
+                        text: root.portName
+                        color: root.isConnected ? Theme.statusSuccessColor : Theme.headingColor
+                        font.pixelSize: Theme.fontMd
+                        font.weight: Font.Bold
+                        font.family: Theme.uiFontFamily
+                        elide: Text.ElideMiddle
                     }
                 }
             }
         }
-    }
 
-    // ═══════════════════════════════════════════════════════════════════════
-    //  ROW 2: Wafer & Sensor + Directory (65%) | Total Runtime (35%)
-    // ═══════════════════════════════════════════════════════════════════════
-    RowLayout {
-        Layout.fillWidth: true
-        Layout.preferredHeight: 90
-        Layout.maximumHeight: 90
-        spacing: 8
-
-        RowLayout {
-            Layout.preferredWidth: 65
+        // ── Wafer & Sensor Data: far right, spans both rows ──
+        Rectangle {
+            Layout.rowSpan: 2
             Layout.fillWidth: true
             Layout.fillHeight: true
-            spacing: 8
+            color: Theme.cardBackground
+            border.color: Theme.cardBorder
+            border.width: 1
+            radius: Theme.radiusSm
 
-            Rectangle {
-                Layout.fillWidth: true
-                Layout.fillHeight: true
-                color: Theme.cardBackground
-                border.color: Theme.cardBorder
-                border.width: 1
-                radius: Theme.radiusSm
+            ColumnLayout {
+                anchors.fill: parent
+                anchors.margins: Theme.panelPadding
+                spacing: 4
 
-                ColumnLayout {
-                    anchors.fill: parent
-                    anchors.margins: Theme.panelPadding
-                    spacing: 6
-
-                    ColumnLayout {
-                        Layout.fillWidth: true
-                        spacing: 2
-
-                        Text {
-                            text: "DIRECTORY"
-                            color: Theme.sideMutedText
-                            font.pixelSize: Theme.fontMd
-                            font.weight: Font.Medium
-                            font.letterSpacing: 1.2
-                            font.family: Theme.uiFontFamily
-                        }
-                        Text {
-                            text: deviceController.saveDataDir || "Not configured"
-                            color: Theme.bodyColor
-                            font.pixelSize: Theme.fontSm
-                            font.family: Theme.uiFontFamily
-                            font.italic: true
-                            opacity: 0.7
-                            elide: Text.ElideMiddle
-                            Layout.fillWidth: true
-                        }
-                    }
-
-                    RowLayout {
-                        Layout.fillWidth: true
-                        spacing: 8
-
-                        Button {
-                            id: browseBtn
-                            text: "Browse"
-                            font.pixelSize: Theme.fontSm
-                            font.weight: Font.Medium
-                            font.family: Theme.uiFontFamily
-                            implicitHeight: 24
-                            implicitWidth: 60
-                            hoverEnabled: true
-                            background: Rectangle {
-                                color: browseBtn.hovered ? Theme.buttonNeutralHover : Theme.buttonNeutralBackground
-                                border.color: Theme.cardBorder
-                                border.width: 1
-                                radius: Theme.radiusSm
-                            }
-                            contentItem: Text {
-                                text: browseBtn.text
-                                color: Theme.bodyColor
-                                font: browseBtn.font
-                                horizontalAlignment: Text.AlignHCenter
-                                verticalAlignment: Text.AlignVCenter
-                            }
-                            onClicked: saveDirDialog.open()
-                        }
-
-                        Item { Layout.fillWidth: true }
-
-                        Row {
-                            spacing: 4
-                            visible: root.isConnected
-                            Rectangle {
-                                width: 6; height: 6; radius: 3
-                                color: Theme.statusSuccessColor
-                                anchors.verticalCenter: parent.verticalCenter
-                            }
-                        }
-
-                        Rectangle {
-                            visible: root.csvPath !== ""
-                            width: sessionSavedLabel.implicitWidth + 12
-                            height: 18
-                            radius: 4
-                            color: Theme.fieldBackground
-                            border.color: Theme.sideBorder
-                            border.width: 1
-
-                            Text {
-                                id: sessionSavedLabel
-                                anchors.centerIn: parent
-                                text: "SESSION SAVED"
-                                color: Theme.sideMutedText
-                                font.pixelSize: Theme.fontXs
-                                font.weight: Font.Bold
-                                font.family: Theme.uiFontFamily
-                                font.letterSpacing: 0.6
-                            }
-                        }
-                    }
+                Text {
+                    text: "WAFER & SENSOR DATA"
+                    color: Theme.sideMutedText
+                    font.pixelSize: Theme.fontSm
+                    font.weight: Font.Bold
+                    font.family: Theme.uiFontFamily
+                    font.letterSpacing: 0.6
+                    Layout.bottomMargin: 2
                 }
-            }
 
-            Rectangle {
-                Layout.fillWidth: true
-                Layout.fillHeight: true
-                color: Theme.cardBackground
-                border.color: Theme.cardBorder
-                border.width: 1
-                radius: Theme.radiusSm
+                GridLayout {
+                    Layout.fillWidth: true
+                    Layout.fillHeight: true
+                    columns: 2
+                    rowSpacing: 6
+                    columnSpacing: 16
 
-                ColumnLayout {
-                    anchors.fill: parent
-                    anchors.margins: Theme.panelPadding
-                    spacing: 8
+                    GridCell {
+                        id: waferInfoFamilyCell
+                        label: "Family Code"
+                        value: {
+                            var info = deviceController.lastWaferInfo;
+                            return (info && info.length > 0 && info[0]) ? info[0] : "—";
+                        }
+                    }
+                    GridCell {
+                        id: waferSerialCell
+                        label: "Serial"
+                        value: {
+                            var info = deviceController.lastWaferInfo;
+                            return (info && info.length > 1 && info[1]) ? info[1] : "—";
+                        }
+                    }
 
-                    Item {
+                    Rectangle {
+                        Layout.columnSpan: 2
                         Layout.fillWidth: true
-                        Layout.fillHeight: true
+                        Layout.preferredHeight: 1
+                        color: Theme.cardBorder
+                        opacity: 0.5
+                    }
 
-                        GridLayout {
-                            anchors.fill: parent
-                            columns: 2
-                            rowSpacing: 6
-                            columnSpacing: 16
-
-                            GridCell {
-                                id: waferInfoFamilyCell
-                                label: "Family Code"
-                                value: {
-                                    var info = deviceController.lastWaferInfo;
-                                    return (info && info.length > 0 && info[0]) ? info[0] : "—";
-                                }
-                            }
-                            GridCell {
-                                id: waferCyclesCell
-                                label: "Cycles Completed"
-                                value: {
-                                    var info = deviceController.lastWaferInfo;
-                                    return (info && info.length > 5 && info[5] !== undefined) ? String(info[5]) : "—";
-                                }
-                                isRight: true
-                                active: root.waferDetected
-                            }
-                            GridCell {
-                                id: waferSerialCell
-                                label: "Serial"
-                                value: {
-                                    var info = deviceController.lastWaferInfo;
-                                    return (info && info.length > 1 && info[1]) ? info[1] : "—";
-                                }
-                            }
-                            GridCell {
-                                id: waferSensorsCell
-                                label: "Sensors"
-                                value: {
-                                    var info = deviceController.lastWaferInfo;
-                                    return (info && info.length > 2 && info[2]) ? String(info[2]) : "—";
-                                }
-                                isRight: true
-                            }
+                    GridCell {
+                        id: waferCyclesCell
+                        label: "Cycles Completed"
+                        value: {
+                            var info = deviceController.lastWaferInfo;
+                            return (info && info.length > 5 && info[5] !== undefined) ? String(info[5]) : "—";
+                        }
+                        active: root.waferDetected
+                    }
+                    GridCell {
+                        id: waferSensorsCell
+                        label: "Sensors"
+                        value: {
+                            var info = deviceController.lastWaferInfo;
+                            return (info && info.length > 2 && info[2]) ? String(info[2]) : "—";
                         }
                     }
                 }
             }
         }
 
+        // ── Directory: bottom-left cell ──
+        Rectangle {
+            Layout.fillWidth: true
+            Layout.fillHeight: true
+            color: Theme.cardBackground
+            border.color: Theme.cardBorder
+            border.width: 1
+            radius: Theme.radiusSm
+
+            ColumnLayout {
+                anchors.fill: parent
+                anchors.margins: Theme.panelPadding
+                spacing: 6
+
+                RowLayout {
+                    Layout.fillWidth: true
+                    spacing: 8
+
+                    Text {
+                        text: "DIRECTORY"
+                        color: Theme.sideMutedText
+                        font.pixelSize: Theme.fontSm
+                        font.bold: true
+                        font.letterSpacing: 1.5
+                        font.family: Theme.uiFontFamily
+                        Layout.fillWidth: true
+                    }
+
+                    Rectangle {
+                        visible: root.csvPath !== ""
+                        implicitWidth: sessionSavedLabel.implicitWidth + 12
+                        implicitHeight: 18
+                        radius: 4
+                        color: Theme.fieldBackground
+                        border.color: Theme.sideBorder
+                        border.width: 1
+
+                        Text {
+                            id: sessionSavedLabel
+                            anchors.centerIn: parent
+                            text: "SESSION SAVED"
+                            color: Theme.sideMutedText
+                            font.pixelSize: Theme.fontXs
+                            font.weight: Font.Bold
+                            font.family: Theme.uiFontFamily
+                            font.letterSpacing: 0.6
+                        }
+                    }
+                }
+
+                Item { Layout.fillHeight: true }
+
+                RowLayout {
+                    Layout.fillWidth: true
+                    spacing: 12
+
+                    // Path pinned bottom-left
+                    Text {
+                        text: deviceController.saveDataDir || "Not configured"
+                        color: Theme.bodyColor
+                        font.pixelSize: Theme.fontMd
+                        font.family: Theme.uiFontFamily
+                        font.italic: true
+                        opacity: 0.7
+                        elide: Text.ElideMiddle
+                        Layout.fillWidth: true
+                    }
+
+                    Button {
+                        id: browseBtn
+                        text: "Select Folder"
+                        font.pixelSize: Theme.fontSm
+                        font.weight: Font.Medium
+                        font.family: Theme.uiFontFamily
+                        implicitHeight: 24
+                        hoverEnabled: true
+                        background: Rectangle {
+                            color: browseBtn.hovered ? Theme.buttonNeutralHover : Theme.buttonNeutralBackground
+                            border.color: Theme.cardBorder
+                            border.width: 1
+                            radius: Theme.radiusSm
+                        }
+                        contentItem: Text {
+                            text: browseBtn.text
+                            color: Theme.bodyColor
+                            font: browseBtn.font
+                            horizontalAlignment: Text.AlignHCenter
+                            verticalAlignment: Text.AlignVCenter
+                        }
+                        onClicked: dirOnlyDialog.open()
+                    }
+                }
+            }
+        }
+
+        // ── Total Runtime: bottom center ──
         StatCard {
             id: runtimeCard
-            Layout.preferredWidth: 35
+            label: "TOTAL RUNTIME"
             value: {
                 var info = deviceController.lastWaferInfo;
-                return (info && info.length > 4 && info[4] !== undefined) ? info[4] + "s" : "—";
+                if (!(info && info.length > 4 && info[4] !== undefined)) return "—";
+                var secs = parseFloat(info[4]);
+                if (isNaN(secs)) return info[4] + "s";
+                var m = Math.floor(secs / 60);
+                var s = Math.round(secs % 60);
+                return secs + "s / " + m + ":" + (s < 10 ? "0" : "") + s + " min";
             }
-            label: "TOTAL RUNTIME"
         }
     }
 
@@ -467,10 +498,20 @@ ColumnLayout {
             anchors.fill: parent
             spacing: 0
 
-            Rectangle {
-                Layout.fillWidth: true
-                Layout.preferredHeight: 36
-                color: Theme.subtleSectionBackground
+             Rectangle {
+                 Layout.fillWidth: true
+                 Layout.preferredHeight: 36
+                 color: Theme.subtleSectionBackground
+                 radius: Theme.radiusMd
+
+                 // Cover bottom corners so only top-left and top-right are rounded
+                 Rectangle {
+                     anchors.bottom: parent.bottom
+                     anchors.left: parent.left
+                     anchors.right: parent.right
+                     height: parent.radius
+                     color: parent.color
+                 }
 
                 RowLayout {
                     anchors.fill: parent
@@ -478,66 +519,27 @@ ColumnLayout {
                     anchors.rightMargin: Theme.panelPadding
                     spacing: 8
 
-                    Text {
-                        text: "📄"
-                        font.pixelSize: Theme.fontSm
+                    IconImage {
+                        source: "icons/file-text.svg"
+                        width: 14; height: 14
+                        sourceSize.width: 14
+                        sourceSize.height: 14
+                        color: Theme.sideMutedText
                         visible: root.csvPath !== ""
                         Layout.alignment: Qt.AlignVCenter
                     }
 
                     Label {
-                        text: root.csvPath !== "" ? root.csvPath.split("/").pop() : "ACTIVITY LOG"
-                        color: Theme.bodyColor
-                        font.pixelSize: root.csvPath !== "" ? Theme.fontMd : Theme.fontSm
-                        font.letterSpacing: root.csvPath !== "" ? 0 : 1.8
-                        font.weight: Font.Medium
+                        text: (root.csvPath !== "" ? root.csvPath.split("/").pop() : "ACTIVITY LOG").toUpperCase()
+                        color: Theme.sideMutedText
+                        font.pixelSize: Theme.fontMd
+                        font.letterSpacing: 1.5
+                        font.bold: true
                         font.family: Theme.uiFontFamily
                         elide: Text.ElideMiddle
                         Layout.fillWidth: true
                         Layout.alignment: Qt.AlignVCenter
                     }
-
-                    Button {
-                        id: refreshSessionBtn
-                        text: "Refresh"
-                        font.pixelSize: Theme.fontSm
-                        font.family: Theme.uiFontFamily
-                        implicitHeight: 24
-                        hoverEnabled: true
-                        background: Rectangle {
-                            color: refreshSessionBtn.hovered ? Theme.buttonNeutralHover : "transparent"
-                            radius: Theme.radiusSm
-                        }
-                        contentItem: Text {
-                            text: refreshSessionBtn.text
-                            color: Theme.bodyColor
-                            font: refreshSessionBtn.font
-                            horizontalAlignment: Text.AlignHCenter
-                            verticalAlignment: Text.AlignVCenter
-                        }
-                        onClicked: deviceController.clearSession()
-                    }
-
-                    Button {
-                        id: clearLogBtn
-                        text: "Clear"
-                        font.pixelSize: Theme.fontSm
-                        font.family: Theme.uiFontFamily
-                        implicitHeight: 24
-                        hoverEnabled: true
-                        background: Rectangle {
-                            color: clearLogBtn.hovered ? Theme.buttonNeutralHover : "transparent"
-                            radius: Theme.radiusSm
-                        }
-                        contentItem: Text {
-                            text: clearLogBtn.text
-                            color: Theme.bodyColor
-                            font: clearLogBtn.font
-                            horizontalAlignment: Text.AlignHCenter
-                            verticalAlignment: Text.AlignVCenter
-                        }
-                        onClicked: deviceController.clearActivityLog()
-                    }
                 }
 
                 Rectangle {
@@ -558,7 +560,9 @@ ColumnLayout {
                 TextArea {
                     id: activityLog
                     width: parent.width
-                    text: qsTr("Welcome — use the side rail to detect a wafer, or import data to review.")
+                    // Bound to backend so log survives tab switches (Loader
+                    // destroys this tab); clears only via Clear Log / restart.
+                    text: deviceController.activityLog || qsTr("Welcome — use the side rail to detect a wafer, or import data to review.")
                     readOnly: true
                     font.family: "monospace"
                     font.pixelSize: Theme.fontSm
@@ -569,12 +573,6 @@ ColumnLayout {
             }
         }
 
-        Connections {
-            target: deviceController
-            function onActivityLogUpdated(newLog) {
-                activityLog.text = newLog ? newLog : qsTr("Welcome — use the side rail to detect a wafer, or import data to review.");
-            }
-        }
     }
 
     // ═══════════════════════════════════════════════════════════════════════
@@ -626,6 +624,13 @@ ColumnLayout {
                 root.dataRows = result.rows;
                 root.dataCols = result.cols;
                 root.csvPath = result.csv_path || "";
+                if (root.csvPath) {
+                    metaWafer.text = result.serialNumber || "";
+                    metaDate.text = Qt.formatDateTime(new Date(), "yyyy-MM-dd hh:mm:ss");
+                    metaChamber.text = settingsModel.chamberId || "";
+                    metaNotes.text = "";
+                    editCsvDialog.open();
+                }
             } else {
                 root.dataParsed = false;
             }

src/pygui/ISC/Tabs/WaferMapTab.qml

@@ -1,6 +1,6 @@
 import QtQuick
 import QtQuick.Controls
-import QtQuick.Dialogs
+import QtQuick.Controls.impl
 import QtQuick.Layouts
 import ISC
 import ISC.Tabs.components
@@ -10,30 +10,26 @@ Item {
     id: root
     anchors.fill: parent
 
-    // Live elapsed-time counter
-    property int _liveSecs: 0
-    Timer {
-        id: liveTimer
-        interval: 1000
-        repeat: true
-        running: streamController.mode === "live" && streamController.state !== "idle"
-        onTriggered: root._liveSecs++
-        onRunningChanged: if (!running)
-            root._liveSecs = 0
-    }
-    function fmtTime(s) {
-        var m = Math.floor(s / 60);
-        var ss = s % 60;
-        return (m < 10 ? "0" : "") + m + ":" + (ss < 10 ? "0" : "") + ss;
-    }
-    // Wire streamController.trendData (Signal(str) carrying JSON list of floats)
-    // into the trend chart's data property. The slot parseJsonToData() is defined
-    // on the Python TrendChartItem; we use it so malformed payloads are logged
-    // there instead of crashing the QML binding.
+    // Wire streamController.trendDelta (Signal(str) carrying one new
+    // [elapsed_s, value] pair per live frame) into the trend chart, which
+    // accumulates its own bounded 60s window. trendReset clears it when a
+    // new stream starts. Parsing happens on the Python TrendChartItem side
+    // so malformed payloads are logged there instead of crashing the QML
+    // binding.
+    property string loadErrorMessage: ""
     Connections {
         target: streamController
-        function onTrendData(avgsJson) {
-            trendChart.setDataFromJson(avgsJson);
+        function onTrendDelta(deltaJson) {
+            trendChart.appendDelta(deltaJson);
+        }
+        function onTrendReset() {
+            trendChart.clearTrend();
+        }
+        function onLoadedFileChanged() {
+            root.loadErrorMessage = "";
+        }
+        function onLoadFileError(message) {
+            root.loadErrorMessage = message;
         }
     }
 
@@ -47,110 +43,6 @@ Item {
             Layout.fillWidth: true
             spacing: 10
 
-            // Mode toggle
-            TabBar {
-                id: modeBar
-                currentIndex: 0  // Default to "Review"
-                spacing: 2
-                padding: 2
-                background: Rectangle {
-                    color: Theme.subtleSectionBackground
-                    radius: Theme.radiusSm
-                    border.color: Theme.cardBorder
-                    border.width: Theme.borderThin
-                }
-                TabButton {
-                    text: "Review"
-                    implicitWidth: 64
-                    implicitHeight: 28
-                    background: Rectangle {
-                        color: parent.checked ? Theme.tabActiveBackground : "transparent"
-                        radius: Theme.radiusSm - 1
-                    }
-                    contentItem: Text {
-                        text: parent.text
-                        color: parent.checked ? Theme.headingColor : Theme.bodyColor
-                        font.pixelSize: Theme.fontSm
-                        font.weight: parent.checked ? Font.Medium : Font.Normal
-                        horizontalAlignment: Text.AlignHCenter
-                        verticalAlignment: Text.AlignVCenter
-                    }
-                }
-                TabButton {
-                    text: "Live"
-                    enabled: deviceController.connectionStatus === "Connected"
-                    opacity: enabled ? 1.0 : 0.4
-                    implicitWidth: 58
-                    implicitHeight: 28
-                    background: Rectangle {
-                        color: parent.checked ? Theme.tabActiveBackground : "transparent"
-                        radius: Theme.radiusSm - 1
-                    }
-                    contentItem: Text {
-                        text: parent.text
-                        color: parent.checked ? Theme.headingColor : Theme.bodyColor
-                        font.pixelSize: Theme.fontSm
-                        font.weight: parent.checked ? Font.Medium : Font.Normal
-                        horizontalAlignment: Text.AlignHCenter
-                        verticalAlignment: Text.AlignVCenter
-                    }
-                }
-                onCurrentIndexChanged: if (currentIndex === 1) {
-                    // Guard: revert to Review if not connected
-                    if (deviceController.connectionStatus !== "Connected") {
-                        currentIndex = 0;
-                        return;
-                    }
-                    // Entering Live mode
-                    streamController.setMode("live");
-                    var fc = "";
-                    if (deviceController.lastWaferInfo && deviceController.lastWaferInfo.length > 0) {
-                        fc = deviceController.lastWaferInfo[0];
-                    }
-                    streamController.startStream(deviceController.selectedPort, fc);
-                } else {
-                    // Entering Review Mode (automatically calls stopStream in backend)
-                    streamController.setMode("review");
-                }
-            }
-
-            // Live source info: WiFi icon + port · serial
-            RowLayout {
-                visible: streamController.mode === "live"
-                spacing: 5
-                // WiFi icon (Unicode approximation; swap for SVG if available)
-                Label {
-                    id: liveIndicator
-                    text: "◉"
-                    color: (deviceController.connectionStatus === "Connected" && streamController.state !== "idle") ? Theme.liveColor : Theme.bodyColor
-                    font.pixelSize: Theme.fontSm
-
-                    SequentialAnimation on opacity {
-                        running: deviceController.connectionStatus === "Connected" && streamController.state !== "idle"
-                        loops: Animation.Infinite
-                        NumberAnimation {
-                            to: 0.2
-                            duration: 600
-                            easing.type: Easing.InOutQuad
-                        }
-                        NumberAnimation {
-                            to: 1.0
-                            duration: 600
-                            easing.type: Easing.InOutQuad
-                        }
-                        onRunningChanged: {
-                            if (!running)
-                                liveIndicator.opacity = 1.0;
-                        }
-                    }
-                }
-                Label {
-                    text: "Live stream"
-                    color: Theme.bodyColor
-                    font.pixelSize: Theme.fontXs
-                }
-            }
-
             Item {
                 Layout.fillWidth: true
             }
@@ -205,44 +97,40 @@ Item {
                     font.letterSpacing: 1.2
                 }
             }
+        }
 
-            // LIVE timer
-            // RowLayout {
-            //     spacing: 5
-            //     visible: streamController.mode === "live" && streamController.state !== "idle"
-            //     Rectangle {
-            //         width: 7; height: 7; radius: 4
-            //         color: Theme.liveColor
-            //     }
-            //     Label {
-            //         text: "LIVE  " + root.fmtTime(root._liveSecs)
-            //         color: Theme.liveColor
-            //         font.pixelSize: Theme.fontXs
-            //         font.weight: Font.Medium
-            //         font.letterSpacing: 0.8
-            //     }
-            // }
+        // ── Load error banner ───────────────────────────────────────────
+        Rectangle {
+            Layout.fillWidth: true
+            Layout.preferredHeight: errorRow.implicitHeight + 16
+            visible: root.loadErrorMessage !== ""
+            color: Theme.errorSurface
+            border.color: Theme.statusErrorColor
+            border.width: 1
+            radius: Theme.radiusSm
 
-            // IDLE label (review / not connected)
-            // Label {
-            //     visible: streamController.mode === "review" || streamController.state === "idle"
-            //     text: streamController.state.toUpperCas`e`()
-            //     color: Theme.bodyColor
-            //     font.pixelSize: Theme.fontXs
-            //     font.weight: Font.Medium
-            //     font.letterSpacing: 1.2
-            // }
-            Button {
-                text: "Export PNG"
-                onClicked: exportDialog.open()
-            }
+            RowLayout {
+                id: errorRow
+                anchors.fill: parent
+                anchors.margins: 8
+                spacing: 8
 
-            FileDialog {
-                id: exportDialog
-                title: "Export Wafer Map"
-                fileMode: FileDialog.SaveFile
-                nameFilters: ["PNG files (*.png)"]
-                onAccepted: waferView.exportImage(String(selectedFile).replace(/^file:\/\//, ""))
+                IconImage {
+                    source: "icons/triangle-alert.svg"
+                    width: 16; height: 16
+                    sourceSize.width: 16
+                    sourceSize.height: 16
+                    color: Theme.errorTextSoft
+                    Layout.alignment: Qt.AlignTop
+                }
+
+                Label {
+                    text: root.loadErrorMessage
+                    color: Theme.errorTextSoft
+                    font.pixelSize: Theme.fontSm
+                    wrapMode: Text.WordWrap
+                    Layout.fillWidth: true
+                }
             }
         }
 
@@ -256,55 +144,78 @@ Item {
             ColumnLayout {
                 Layout.fillWidth: true
                 Layout.fillHeight: true
-                spacing: 8
+                spacing: 16
 
                 WaferMapView {
                     id: waferView
                     Layout.fillWidth: true
                     Layout.fillHeight: true
+                    Layout.preferredHeight: 400
+                    Layout.minimumHeight: 280
                     blend: readoutPanel.heatmapBlend
                     showLabels: readoutPanel.showLabels
+                    showExtremes: readoutPanel.showExtremes
                     showThickness: readoutPanel.showThickness
                 }
                 Rectangle {
                     id: trendPane
                     Layout.fillWidth: true
-                    implicitHeight: 160
+                    Layout.fillHeight: false
+                    Layout.preferredHeight: 220
+                    Layout.minimumHeight: 120
                     visible: trendChart.hasData && streamController.mode === "live"
                     color: Theme.cardBackground
                     border.color: Theme.cardBorder
                     border.width: 1
                     radius: Theme.radiusMd
 
-                    TrendChartItem {
-                        id: trendChart
+                    ColumnLayout {
                         anchors.fill: parent
                         anchors.margins: 8
+                        spacing: 10
+
+                        TrendChartItem {
+                            id: trendChart
+                            Layout.fillWidth: true
+                            Layout.fillHeight: true
+                        }
                     }
                 }
 
                 Item {
                     Layout.fillWidth: true
-                    implicitHeight: 16
+                    visible: transportBar.hasContent
+                    implicitHeight: trendPane.visible ? 52 : 16
                 }
                 TransportBar {
+                    id: transportBar
                     Layout.fillWidth: true
                 }
             }
 
-            // Readout panel — floating wrapper box
-            Rectangle {
-                Layout.preferredWidth: 220
+            // Readout panel — scrolls instead of clipping so the last card
+            // (Thresholds) is always reachable even if content outgrows
+            // the available height (e.g. once E-C delta rows appear).
+            ScrollView {
+                Layout.preferredWidth: Theme.rightRailWidth
                 Layout.fillHeight: true
-                color: "transparent"
-                border.color: "transparent"
-                border.width: 0
                 clip: true
+                ScrollBar.horizontal.policy: ScrollBar.AlwaysOff
 
                 ReadoutPanel {
                     id: readoutPanel
-                    anchors.fill: parent
-                    anchors.margins: 0
+                    width: parent.width
+                    hasThicknessData: waferView.hasThickness
+                    onExportRequested: function(filePath, extra) {
+                        waferView.exportImage(filePath, extra);
+                    }
+                    onThicknessFileChosen: function(filePath) {
+                        var err = waferView.loadThickness(filePath);
+                        if (err !== "") {
+                            root.loadErrorMessage = err;
+                            readoutPanel.showThickness = false;
+                        }
+                    }
                 }
             }
         }

src/pygui/ISC/Tabs/components/AppToolTip.qml

@@ -0,0 +1,25 @@
+import QtQuick
+import QtQuick.Controls
+import ISC
+
+// Single seam for tooltip chrome — every hover tip in the app instantiates
+// this instead of styling QtQuick.Controls ToolTip.background/contentItem
+// inline at each call site.
+ToolTip {
+    id: root
+    delay: 400
+    font.pixelSize: Theme.fontXs
+    font.family: Theme.uiFontFamily
+
+    contentItem: Text {
+        text: root.text
+        color: Theme.headingColor
+        font: root.font
+    }
+    background: Rectangle {
+        color: Theme.cardBackground
+        border.color: Theme.sideBorder
+        border.width: 1
+        radius: Theme.radiusXs
+    }
+}

src/pygui/ISC/Tabs/components/ComparisonChartCard.qml

@@ -0,0 +1,260 @@
+import QtQuick
+import QtQuick.Controls
+import QtQuick.Controls.impl
+import QtQuick.Layouts
+import ISC
+
+// Curve overlay chart card with the alignment timeline scrubber.
+PanelBox {
+    id: card
+
+    required property var trendDataA
+    required property var trendDataB
+    required property int seriesLen
+    required property bool hasSeries
+    required property bool comparing
+
+    // Scrubber position — the internal Slider is private; consumers
+    // read/write frameIndex and call focusScrubber().
+    property alias frameIndex: scrubber.value
+
+    function focusScrubber() { scrubber.forceActiveFocus() }
+
+    implicitHeight: chartCol.implicitHeight + 24
+
+    ColumnLayout {
+        id: chartCol
+        anchors.fill: parent
+        anchors.margins: 12
+        spacing: 8
+
+        RowLayout {
+            Layout.fillWidth: true
+            SectionTitle {
+                text: "CURVE OVERLAY"
+                Layout.fillWidth: true
+            }
+            Row {
+                spacing: 16
+                visible: card.hasSeries
+                Row {
+                    spacing: 4
+                    Rectangle { width: 12; height: 3; radius: 1.5; color: Theme.primaryAccent; anchors.verticalCenter: parent.verticalCenter }
+                    Label { text: "Run A"; font.pixelSize: Theme.fontXs; color: Theme.bodyColor }
+
+                }
+                Row {
+                    spacing: 4
+                    Rectangle { width: 12; height: 3; radius: 1.5; color: Theme.themeSkill; anchors.verticalCenter: parent.verticalCenter }
+                    Label { text: "Run B"; font.pixelSize: Theme.fontXs; color: Theme.bodyColor }
+                }
+            }
+        }
+
+        Rectangle {
+            Layout.fillWidth: true
+            Layout.preferredHeight: 200
+            color: Theme.fieldBackground
+            border.color: Theme.cardBorder
+            border.width: 1
+            radius: Theme.radiusSm
+            clip: true
+
+            Canvas {
+                id: overlayCanvas
+                anchors.fill: parent
+                visible: card.hasSeries
+
+                readonly property real padLeft: 50
+                readonly property real padRight: 16
+                readonly property real padTop: 24
+                readonly property real padBottom: 36
+
+                // Nice tick step (1/2/5 × 10^k) — same scheme as TrendChartItem,
+                // so labels land on round numbers instead of raw data min/max.
+                function niceStep(rawStep) {
+                    var mag = Math.pow(10, Math.floor(Math.log10(rawStep)))
+                    return [1, 2, 5, 10].map(function (s) { return s * mag })
+                                        .find(function (s) { return s >= rawStep })
+                }
+
+                function drawGrid(ctx, minV, maxV, yStep, dataLen) {
+                    var plotW = width - padLeft - padRight
+                    var plotH = height - padTop - padBottom
+                    var range = (maxV - minV) || 1
+
+                    ctx.strokeStyle = Theme.chartGridLine
+                    ctx.lineWidth = 1
+                    ctx.fillStyle = Theme.chartAxisText
+                    ctx.font = "10px " + Theme.uiFontFamily
+                    ctx.textAlign = "right"
+
+                    var ySteps = Math.max(1, Math.round(range / yStep))
+                    var yDec = Math.max(0, -Math.floor(Math.log10(yStep)))
+                    for (var yi = 0; yi <= ySteps; yi++) {
+                        var yFrac = yi / ySteps
+                        var yPx = padTop + plotH * yFrac
+                        var yVal = maxV - yFrac * range
+
+                        ctx.beginPath()
+                        ctx.moveTo(padLeft, yPx)
+                        ctx.lineTo(padLeft + plotW, yPx)
+                        ctx.stroke()
+
+                        ctx.fillText(yVal.toFixed(yDec), padLeft - 6, yPx + 3)
+                    }
+
+                    ctx.textAlign = "center"
+                    var xMax = dataLen - 1
+                    if (xMax > 0) {
+                        var xStep = niceStep(xMax / 5 || 1)
+                        for (var xIdx = 0; xIdx <= xMax; xIdx += xStep) {
+                            var xPx = padLeft + (xIdx / xMax) * plotW
+                            ctx.fillText(xIdx.toString(), xPx, height - 20)
+                        }
+                    }
+
+                    ctx.save()
+                    ctx.translate(14, padTop + plotH / 2)
+                    ctx.rotate(-Math.PI / 2)
+                    ctx.textAlign = "center"
+                    ctx.font = "12px " + Theme.uiFontFamily
+                    ctx.fillText("Celcius (°C)", 0, 0)
+                    ctx.restore()
+
+                    ctx.textAlign = "center"
+                    ctx.font = "12px " + Theme.uiFontFamily
+                    ctx.fillText("Frame", padLeft + plotW / 2, height - 4)
+                }
+
+                function drawSeries(ctx, series, minV, range, color, dataLen) {
+                    // x is mapped against the shared frame domain (dataLen), not the
+                    // series' own length — otherwise a shorter run's line stretches to
+                    // fill the whole plot instead of stopping where its data ends.
+                    if (series.length < 2) return
+                    var plotW = width - padLeft - padRight
+                    var plotH = height - padTop - padBottom
+
+                    ctx.strokeStyle = color
+                    ctx.lineWidth = 2
+                    ctx.beginPath()
+                    for (var i = 0; i < series.length; i++) {
+                        var x = padLeft + (i / (dataLen - 1)) * plotW
+                        var y = padTop + plotH - ((series[i] - minV) / range) * plotH
+                        if (i === 0) ctx.moveTo(x, y)
+                        else ctx.lineTo(x, y)
+                    }
+                    ctx.stroke()
+                }
+
+                function drawScrubMarker(ctx) {
+                    if (card.seriesLen < 2) return
+                    var plotW = width - padLeft - padRight
+                    var x = padLeft + (scrubber.value / (card.seriesLen - 1)) * plotW
+                    ctx.strokeStyle = Theme.primaryAccent
+                    ctx.lineWidth = 1.5
+                    ctx.setLineDash([3, 3])
+                    ctx.beginPath()
+                    ctx.moveTo(x, padTop)
+                    ctx.lineTo(x, height - padBottom)
+                    ctx.stroke()
+                    ctx.setLineDash([])
+                }
+
+                onPaint: {
+                    var ctx = getContext("2d")
+                    ctx.reset()
+                    if (!card.hasSeries) return
+                    var all = card.trendDataA.concat(card.trendDataB)
+                    var minV = Math.min.apply(null, all)
+                    var maxV = Math.max.apply(null, all)
+                    var padding = (maxV - minV) * 0.05
+                    minV -= padding
+                    maxV += padding
+                    // Snap bounds to nice-step multiples -> stable round-number axis
+                    var yStep = niceStep((maxV - minV) / 5 || 1)
+                    minV = Math.floor(minV / yStep) * yStep
+                    maxV = Math.ceil(maxV / yStep) * yStep
+                    var range = (maxV - minV) || 1
+
+                    drawGrid(ctx, minV, maxV, yStep, card.seriesLen)
+                    drawSeries(ctx, card.trendDataA, minV, range, Theme.primaryAccent, card.seriesLen)
+                    drawSeries(ctx, card.trendDataB, minV, range, Theme.themeSkill, card.seriesLen)
+                    drawScrubMarker(ctx)
+                }
+
+                Connections {
+                    target: card
+                    function onTrendDataAChanged() { overlayCanvas.requestPaint() }
+                    function onTrendDataBChanged() { overlayCanvas.requestPaint() }
+                }
+                Connections {
+                    target: scrubber
+                    function onValueChanged() { overlayCanvas.requestPaint() }
+                }
+            }
+
+            // Empty state
+            ColumnLayout {
+                anchors.centerIn: parent
+                visible: !card.hasSeries
+                spacing: 8
+
+                IconImage {
+                    Layout.alignment: Qt.AlignHCenter
+                    visible: !card.comparing
+                    source: "../icons/bar-chart.svg"
+                    width: 32; height: 32
+                    sourceSize.width: 32
+                    sourceSize.height: 32
+                    color: Theme.sideMutedText
+                }
+                Label {
+                    Layout.alignment: Qt.AlignHCenter
+                    text: card.comparing ? "Running DTW comparison…" : "Select two runs and run comparison"
+                    color: Theme.bodyColor
+                    font.pixelSize: Theme.fontSm
+                }
+                Label {
+                    Layout.alignment: Qt.AlignHCenter
+                    visible: !card.comparing
+                    text: "Click a run box on the right, then select a file from the left panel."
+                    color: Theme.sideMutedText
+                    font.pixelSize: Theme.fontXs
+                }
+            }
+        }
+
+        // ── Alignment Timeline Scrubber ────────────
+        ColumnLayout {
+            Layout.fillWidth: true
+            spacing: 4
+            visible: card.hasSeries
+
+            Rectangle {
+                Layout.fillWidth: true
+                height: 1
+                color: Theme.cardBorder
+            }
+
+            SectionTitle {
+                text: "TIMELINE SCRUBBER"
+                Layout.fillWidth: true
+                Layout.topMargin: 8
+            }
+
+            Slider {
+                id: scrubber
+                Layout.fillWidth: true
+                leftPadding: overlayCanvas.padLeft
+                rightPadding: overlayCanvas.padRight
+                from: 0
+                to: Math.max(1, card.seriesLen - 1)
+                stepSize: 1
+                value: 0
+            }
+
+
+        }
+    }
+}

src/pygui/ISC/Tabs/components/ComparisonSidePanel.qml

@@ -0,0 +1,239 @@
+import QtQuick
+import QtQuick.Controls
+import QtQuick.Layouts
+import ISC
+
+// Right-column bento stack: DTW readout, overlap settings, frame/time
+// controls, and scrubber readout. Pure view — all comparison state lives
+// on DataTab; scrubber writes go up via frameIndexRequested.
+ColumnLayout {
+    id: panel
+
+    required property real warpingDistance
+    required property int frameOffset
+    required property real frameOffsetSeconds
+    required property real maxSensorDeviation
+    required property int seriesLen
+    required property bool hasSeries
+    required property var trendDataA
+    required property var trendDataB
+    required property var timeDataA
+    required property var timeDataB
+    required property var frameForTime   // function(seconds) -> frame index
+    required property real frameIndex    // bound from ComparisonChartCard.frameIndex
+
+    // Overlap settings outputs (consumed by OverlapMapCard via DataTab)
+    property alias overlapEnabled: enableOverlapCheck.checked
+    property alias blendAmount: blendSlider.value
+
+    signal frameIndexRequested(real idx)
+    signal scrubberFocusRequested()
+
+    spacing: 12
+
+    // Bento 3: DTW Comparison Readout
+    PanelBox {
+        Layout.fillWidth: true
+        Layout.preferredHeight: readoutCol.implicitHeight + 24
+
+        ColumnLayout {
+            id: readoutCol
+            anchors.fill: parent
+            anchors.margins: 12
+            spacing: 8
+
+            SectionTitle { text: "DTW READOUT" }
+
+            ReadoutStat {
+                label: "DTW ALIGNMENT DISTANCE"
+                value: panel.warpingDistance >= 0 ? panel.warpingDistance.toFixed(2) : "--"
+                valueColor: panel.warpingDistance >= 0
+                    ? (panel.warpingDistance < 50 ? Theme.metricGood : panel.warpingDistance < 100 ? Theme.metricWarn : Theme.metricBad)
+                    : Theme.sideMutedText
+            }
+            ReadoutStat {
+                label: "TEMPORAL FRAME OFFSET"
+                value: panel.warpingDistance >= 0
+                    ? ((panel.frameOffset >= 0 ? "+" : "") + panel.frameOffset + " frames / "
+                       + (panel.frameOffsetSeconds >= 0 ? "+" : "") + panel.frameOffsetSeconds.toFixed(1) + "s")
+                    : "--"
+                valueColor: panel.warpingDistance >= 0 ? Theme.headingColor : Theme.sideMutedText
+            }
+            ReadoutStat {
+                label: "MAX SENSOR DEVIATION"
+                value: panel.maxSensorDeviation >= 0 ? panel.maxSensorDeviation.toFixed(2) + "°C" : "--"
+                valueColor: panel.maxSensorDeviation >= 0
+                    ? (panel.maxSensorDeviation < 1.0 ? Theme.metricGood : panel.maxSensorDeviation < 3.0 ? Theme.metricWarn : Theme.metricBad)
+                    : Theme.sideMutedText
+            }
+        }
+    }
+
+    // Bento 2: Overlap Map Settings
+    PanelBox {
+        Layout.fillWidth: true
+        Layout.preferredHeight: overlapCol.implicitHeight + 24
+
+        ColumnLayout {
+            id: overlapCol
+            anchors.fill: parent
+            anchors.margins: 12
+            spacing: 8
+
+            SectionTitle { text: "OVERLAP SETTINGS" }
+
+            PanelCheckBox {
+                id: enableOverlapCheck
+                Layout.fillWidth: true
+                checked: true
+                text: "Enable Overlap Map"
+                font.pixelSize: Theme.fontSm
+            }
+
+            ColumnLayout {
+                Layout.fillWidth: true
+                spacing: 6
+                visible: enableOverlapCheck.checked
+
+                Rectangle {
+                    Layout.fillWidth: true
+                    height: 1
+                    color: Theme.cardBorder
+                }
+
+                RowLayout {
+                    Layout.fillWidth: true
+                    spacing: 6
+                    Label {
+                        text: "Blend"
+                        font.pixelSize: Theme.fontSm
+                        color: Theme.bodyColor
+                        Layout.preferredWidth: 40
+                    }
+                    PanelSlider {
+                        id: blendSlider
+                        Layout.fillWidth: true
+                        from: 0; to: 100; value: 50
+                        stepSize: 1
+                    }
+                    Label {
+                        text: Math.round(blendSlider.value) + "%"
+                        font.pixelSize: Theme.fontSm
+                        color: Theme.sideMutedText
+                        Layout.preferredWidth: 30
+                    }
+                }
+
+                // Diff color legend
+                Row {
+                    Layout.fillWidth: true
+                    spacing: 10
+                    Row {
+                        spacing: 3
+                        Rectangle { width: 8; height: 8; radius: 4; color: Theme.sensorLow; anchors.verticalCenter: parent.verticalCenter }
+                        Label { text: "B cooler"; font.pixelSize: Theme.fontSm; color: Theme.sideMutedText }
+                    }
+                    Row {
+                        spacing: 3
+                        Rectangle { width: 8; height: 8; radius: 4; color: Theme.sensorInRange; anchors.verticalCenter: parent.verticalCenter }
+                        Label { text: "Match"; font.pixelSize: Theme.fontSm; color: Theme.sideMutedText }
+                    }
+                    Row {
+                        spacing: 3
+                        Rectangle { width: 8; height: 8; radius: 4; color: Theme.sensorHigh; anchors.verticalCenter: parent.verticalCenter }
+                        Label { text: "B hotter"; font.pixelSize: Theme.fontSm; color: Theme.sideMutedText }
+                    }
+                }
+            }
+        }
+    }
+
+    // Bento: Frame / Time Controls
+    PanelBox {
+        Layout.fillWidth: true
+        Layout.preferredHeight: frameTimeCol.implicitHeight + 32
+
+        ColumnLayout {
+            id: frameTimeCol
+            anchors.fill: parent
+            anchors.margins: 16
+            spacing: 20
+
+            SectionTitle { text: "FRAME / TIME" }
+
+            EditableScrubStat {
+                label: "Frame"
+                value: scrubReadout.scrubIdx
+                unit: "/ " + Math.max(0, panel.seriesLen - 1) + (Math.max(0, panel.seriesLen - 1) <= 1 ? " frame" : " frames")
+                editable: panel.hasSeries
+                onValueEdited: (newValue) => {
+                    var maxVal = Math.max(0, panel.seriesLen - 1)
+                    var val = Math.max(0, Math.min(newValue, maxVal))
+                    panel.frameIndexRequested(val)
+                }
+                onEditingDone: panel.scrubberFocusRequested()
+            }
+
+            EditableScrubStat {
+                label: "Time"
+                value: scrubReadout.scrubTime
+                unit: "/ " + scrubReadout.maxTime.toFixed(1) + "s"
+                editable: panel.hasSeries
+                onValueEdited: (newValue) => {
+                    var closestIdx = panel.frameForTime(newValue)
+                    panel.frameIndexRequested(closestIdx)
+                }
+                onEditingDone: panel.scrubberFocusRequested()
+            }
+        }
+    }
+
+    // Bento: Scrub Readout
+    PanelBox {
+        Layout.fillWidth: true
+        Layout.preferredHeight: scrubReadout.implicitHeight + 24
+
+        ColumnLayout {
+            id: scrubReadout
+            anchors.fill: parent
+            anchors.margins: 12
+            spacing: 8
+
+            readonly property int scrubIdx: Math.round(panel.frameIndex)
+            readonly property bool hasA: scrubIdx < panel.trendDataA.length
+            readonly property bool hasB: scrubIdx < panel.trendDataB.length
+            readonly property real tempA: hasA ? panel.trendDataA[scrubIdx] : 0
+            readonly property real tempB: hasB ? panel.trendDataB[scrubIdx] : 0
+            readonly property real scrubTime: {
+                var t = scrubIdx < panel.timeDataA.length ? panel.timeDataA[scrubIdx]
+                      : (scrubIdx < panel.timeDataB.length ? panel.timeDataB[scrubIdx] : 0)
+                return t
+            }
+            readonly property real maxTime: {
+                var ta = panel.timeDataA.length > 0 ? panel.timeDataA[panel.timeDataA.length - 1] : 0
+                var tb = panel.timeDataB.length > 0 ? panel.timeDataB[panel.timeDataB.length - 1] : 0
+                return Math.max(ta, tb)
+            }
+
+            SectionTitle { text: "SCRUBBER READOUT" }
+
+            ReadoutStat {
+                label: "Temp (Run A)"
+                value: scrubReadout.hasA ? scrubReadout.tempA.toFixed(1) + "°C" : "none"
+                valueColor: Theme.primaryAccent
+            }
+            ReadoutStat {
+                label: "Temp (Run B)"
+                value: scrubReadout.hasB ? scrubReadout.tempB.toFixed(1) + "°C" : "none"
+                valueColor: Theme.themeSkill
+            }
+            ReadoutStat {
+                label: "Difference"
+                value: (scrubReadout.hasA && scrubReadout.hasB)
+                    ? Math.abs(scrubReadout.tempA - scrubReadout.tempB).toFixed(1) + "°C" : "none"
+            }
+        }
+    }
+
+    Item { Layout.fillHeight: true }
+}

src/pygui/ISC/Tabs/components/ConnectionFooter.qml

@@ -0,0 +1,102 @@
+import QtQuick
+import QtQuick.Controls
+import QtQuick.Layouts
+import ISC
+
+// ── BOX 3: Hardware Status Footer ──────────────────────────
+Rectangle {
+    Layout.fillWidth: true
+    Layout.preferredHeight: Theme.sideFooterConnection
+    visible: root.selectedTabIndex !== 1
+    radius: Theme.sidePanelRadius
+    border.color: Theme.sideBorder
+    border.width: 1
+    color: Theme.sidePanelBackground
+    clip: true
+
+    ColumnLayout {
+        anchors.fill: parent
+        anchors.margins: 14
+        spacing: 6
+
+        // Row 1: Title
+        Label {
+            text: "CONNECTION FLOW"
+            color: Theme.sideMutedText
+            font.family: Theme.uiFontFamily
+            font.pixelSize: Theme.fontSm
+            font.letterSpacing: 1.5
+            font.bold: true
+            Layout.fillWidth: true
+            elide: Text.ElideRight
+        }
+
+        // Row 2: Port / descriptive text
+        Label {
+            Layout.fillWidth: true
+            text: {
+                if (deviceController.connectionStatus === "Connected")
+                    return deviceController.selectedPort || "Connected"
+                if (deviceController.selectedPort)
+                    return deviceController.selectedPort
+                return "No port selected"
+            }
+            color: Theme.bodyColor
+            font.family: Theme.uiFontFamily
+            font.pixelSize: Theme.fontSm
+            elide: Text.ElideRight
+        }
+
+        Item { Layout.fillHeight: true }
+
+        // Row 3: Mode chip left, status badge bottom-right
+        RowLayout {
+            spacing: 6
+            Layout.fillWidth: true
+
+            Rectangle {
+                width: modeChipLabel.implicitWidth + 12
+                height: 18
+                radius: 4
+                color: Theme.fieldBackground
+                border.color: Theme.sideBorder
+                border.width: 1
+
+                Label {
+                    id: modeChipLabel
+                    anchors.centerIn: parent
+                    text: streamController.mode
+                        ? streamController.mode.toUpperCase() : "REVIEW"
+                    color: Theme.sideMutedText
+                    font.family: Theme.uiFontFamily
+                    font.pixelSize: Theme.fontXs
+                    font.bold: true
+                    font.letterSpacing: 0.8
+                }
+            }
+
+            Item { Layout.fillWidth: true }
+
+            Rectangle {
+                height: 18
+                width: badgeLabel.implicitWidth + 14
+                radius: 9
+                color: {
+                    var s = deviceController.connectionStatus
+                    if (s === "Connected") return Theme.statusSuccessColor
+                    if (s === "Disconnected") return Theme.statusErrorColor
+                    return Theme.statusWarningColor
+                }
+
+                Label {
+                    id: badgeLabel
+                    anchors.centerIn: parent
+                    text: deviceController.connectionStatus || "Disconnected"
+                    color: Theme.statusBadgeText
+                    font.pixelSize: Theme.fontXs
+                    font.bold: true
+                }
+            }
+        }
+    }
+}

src/pygui/ISC/Tabs/components/EditableScrubStat.qml

@@ -0,0 +1,113 @@
+import QtQuick
+import QtQuick.Controls
+import QtQuick.Layouts
+import ISC
+
+// Editable stat box for scrubber readout (styled to match DTW ReadoutCard)
+Rectangle {
+    id: edStat
+    property string label
+    property real value
+    property string unit
+    property string extraText: ""
+    property bool editable: true
+    signal valueEdited(real newValue)
+    // Fires when the input field commits (Enter/focus loss), even if the
+    // entered text was invalid — callers use it to hand focus back to the
+    // timeline scrubber, matching the pre-extraction behavior.
+    signal editingDone()
+
+    Layout.fillWidth: true
+    implicitHeight: edStatRow.implicitHeight + 16
+    radius: Theme.radiusSm
+    color: Theme.subtleSectionBackground
+    border.color: (edStat.editable && inputField.activeFocus) ? Theme.fieldBorderFocus : Theme.cardBorder
+    border.width: (edStat.editable && inputField.activeFocus) ? Theme.borderStrong : Theme.borderThin
+
+    RowLayout {
+        id: edStatRow
+        anchors.fill: parent
+        anchors.margins: 8
+        spacing: 6
+
+        ColumnLayout {
+            Layout.fillWidth: true
+            spacing: 2
+            Label {
+                text: edStat.label.toUpperCase()
+                font.pixelSize: Theme.fontXs
+                font.bold: true
+                font.letterSpacing: 0.2
+                color: Theme.sideMutedText
+            }
+            RowLayout {
+                spacing: 4
+                TextField {
+                    id: inputField
+                    readOnly: !edStat.editable
+                    hoverEnabled: edStat.editable
+                    font.pixelSize: Theme.fontLg
+                    font.bold: true
+                    font.family: Theme.codeFontFamily
+                    color: edStat.editable ? Theme.headingColor : Theme.sideMutedText
+                    verticalAlignment: TextInput.AlignVCenter
+                    horizontalAlignment: TextInput.AlignHCenter
+                    background: Rectangle {
+                        visible: edStat.editable
+                        color: Theme.fieldBackground
+                        radius: Theme.radiusXs
+                        border.color: inputField.activeFocus ? Theme.fieldBorderFocus : (inputField.hovered ? Theme.fieldBorderFocus : Theme.fieldBorder)
+                        border.width: 1
+                    }
+                    padding: 0
+                    leftPadding: edStat.editable ? 6 : 0
+                    rightPadding: edStat.editable ? 6 : 0
+                    topPadding: edStat.editable ? 5 : 0
+                    bottomPadding: edStat.editable ? 5 : 0
+                    selectByMouse: edStat.editable
+                    inputMethodHints: edStat.label === "Time" ? Qt.ImhFormattedNumbersOnly : Qt.ImhDigitsOnly
+                    Layout.preferredWidth: edStat.editable ? Math.max(36, contentWidth + 12) : contentWidth
+                    Layout.preferredHeight: edStat.editable ? 32 : implicitHeight
+
+                    text: edStat.value.toFixed(edStat.label === "Time" ? 1 : 0)
+
+                    onEditingFinished: {
+                        var val = parseFloat(text)
+                        if (!isNaN(val)) {
+                            edStat.valueEdited(val)
+                        }
+                        text = edStat.value.toFixed(edStat.label === "Time" ? 1 : 0)
+                        edStat.editingDone()
+                    }
+
+                    Connections {
+                        target: edStat
+                        function onValueChanged() {
+                            if (!inputField.activeFocus) {
+                                inputField.text = edStat.value.toFixed(edStat.label === "Time" ? 1 : 0)
+                            }
+                        }
+                    }
+                }
+                Label {
+                    text: edStat.unit
+                    font.pixelSize: Theme.fontLg
+                    font.bold: true
+                    font.family: Theme.codeFontFamily
+                    color: edStat.editable ? Theme.headingColor : Theme.sideMutedText
+                    Layout.alignment: Qt.AlignVCenter
+                }
+            }
+        }
+
+        Label {
+            visible: edStat.extraText !== ""
+            text: edStat.extraText
+            font.pixelSize: Theme.fontLg
+            font.bold: true
+            font.family: Theme.codeFontFamily
+            color: Theme.headingColor
+            Layout.alignment: Qt.AlignVCenter
+        }
+    }
+}

src/pygui/ISC/Tabs/components/MetricRow.qml

@@ -0,0 +1,28 @@
+import QtQuick
+import QtQuick.Controls
+import QtQuick.Layouts
+import ISC
+
+RowLayout {
+    property string label
+    property string value
+    property color valueColor: Theme.headingColor
+    Layout.fillWidth: true
+    spacing: 4
+
+    Label {
+        text: label
+        color: Theme.sideMutedText
+        font.family: Theme.uiFontFamily
+        font.pixelSize: Theme.fontMd
+        font.bold: true
+        Layout.fillWidth: true
+    }
+    Label {
+        text: value
+        color: valueColor
+        font.family: Theme.codeFontFamily
+        font.pixelSize: Theme.fontMd
+        font.bold: true
+    }
+}

src/pygui/ISC/Tabs/components/OverlapMapCard.qml

@@ -0,0 +1,86 @@
+import QtQuick
+import QtQuick.Controls
+import QtQuick.Controls.impl
+import QtQuick.Layouts
+import ISC
+import ISC.Wafer
+
+// Wafer overlap map card — renders per-sensor Run A/Run B temperature
+// differences at the current scrub position.
+PanelBox {
+    id: card
+
+    required property var sensorLayout
+    required property var diffValues
+    required property var diffBands      // function(values) -> band thresholds
+    required property string waferShape
+    required property real waferSize
+    required property bool overlapEnabled
+    required property real blendAmount   // 0–100, percent
+
+    ColumnLayout {
+        anchors.fill: parent
+        anchors.margins: 12
+        spacing: 8
+
+        RowLayout {
+            Layout.fillWidth: true
+            SectionTitle {
+                text: "WAFER OVERLAP"
+                Layout.fillWidth: true
+            }
+        }
+
+        Rectangle {
+            Layout.fillWidth: true
+            Layout.fillHeight: true
+            color: Theme.fieldBackground
+            border.color: Theme.cardBorder
+            border.width: 1
+            radius: Theme.radiusSm
+            clip: true
+
+            WaferMapItem {
+                id: overlapMapItem
+                anchors.fill: parent
+                visible: card.sensorLayout.length > 0 && card.overlapEnabled
+                sensors: card.sensorLayout
+                values: card.diffValues
+                bands: card.diffBands(overlapMapItem.values)
+                shape: card.waferShape
+                size: card.waferSize
+                target: 0
+                margin: 1.0
+                blend: card.blendAmount / 100
+                showLabels: true
+                ringColor: Theme.waferRingColor
+                axisColor: Theme.waferAxisColor
+                lowColor: Theme.sensorLow
+                inRangeColor: Theme.sensorInRange
+                highColor: Theme.sensorHigh
+                textColor: Theme.headingColor
+            }
+
+            ColumnLayout {
+                anchors.centerIn: parent
+                visible: card.sensorLayout.length === 0 || !card.overlapEnabled
+                spacing: 4
+                IconImage {
+                    Layout.alignment: Qt.AlignHCenter
+                    source: "../icons/map.svg"
+                    width: 24; height: 24
+                    sourceSize.width: 24
+                    sourceSize.height: 24
+                    color: Theme.sideMutedText
+                }
+                Label {
+                    Layout.alignment: Qt.AlignHCenter
+                    text: !card.overlapEnabled ? "Overlap map disabled"
+                        : "No sensor map available"
+                    color: Theme.bodyColor
+                    font.pixelSize: Theme.fontXs
+                }
+            }
+        }
+    }
+}

src/pygui/ISC/Tabs/components/PanelBox.qml

@@ -0,0 +1,10 @@
+import QtQuick
+import ISC
+
+// Card container for the Data tab bento boxes.
+Rectangle {
+    color: Theme.sidePanelBackground
+    border.color: Theme.sideBorder
+    border.width: 1
+    radius: Theme.sidePanelRadius
+}

src/pygui/ISC/Tabs/components/PanelCheckBox.qml

@@ -0,0 +1,43 @@
+import QtQuick
+import QtQuick.Controls
+import QtQuick.Controls.impl
+import ISC
+
+// Checkbox styled to match MapTab's right-rail ReadoutPanel (square accent
+// indicator + check icon) instead of the platform-default CheckBox look.
+CheckBox {
+    id: toggle
+    indicator: Rectangle {
+        implicitWidth: 18
+        implicitHeight: 18
+        x: toggle.leftPadding
+        y: parent.height / 2 - height / 2
+        radius: Theme.radiusXs
+        color: toggle.checked ? Theme.primaryAccent : "transparent"
+        border.width: Theme.borderThin
+        border.color: toggle.checked ? Theme.primaryAccent : Theme.fieldBorder
+
+        Behavior on color { ColorAnimation { duration: Theme.durationFast } }
+        Behavior on border.color { ColorAnimation { duration: Theme.durationFast } }
+
+        IconImage {
+            anchors.centerIn: parent
+            source: "../icons/check.svg"
+            width: 12; height: 12
+            sourceSize.width: 12
+            sourceSize.height: 12
+            color: Theme.panelBackground
+            opacity: toggle.checked ? 1.0 : 0.0
+            Behavior on opacity { NumberAnimation { duration: Theme.durationFast } }
+        }
+    }
+
+    contentItem: Text {
+        text: toggle.text
+        color: Theme.headingColor
+        font.family: Theme.uiFontFamily
+        verticalAlignment: Text.AlignVCenter
+        leftPadding: toggle.indicator.width + toggle.spacing
+        font.pixelSize: toggle.font.pixelSize || Theme.fontXs
+    }
+}

src/pygui/ISC/Tabs/components/PanelSlider.qml

@@ -0,0 +1,19 @@
+import QtQuick
+import QtQuick.Controls
+import ISC
+
+// Slider styled to match MapTab's right-rail heatmap slider (circular
+// accent handle that grows slightly on press).
+Slider {
+    id: panelSlider
+    handle: Rectangle {
+        x: panelSlider.leftPadding + panelSlider.visualPosition * (panelSlider.availableWidth - width)
+        y: panelSlider.topPadding + panelSlider.availableHeight / 2 - height / 2
+        implicitWidth: 18
+        implicitHeight: 18
+        radius: 9
+        color: Theme.primaryAccent
+        scale: panelSlider.pressed ? 1.15 : 1.0
+        Behavior on scale { NumberAnimation { duration: Theme.durationFast; easing.type: Theme.easeStandard } }
+    }
+}

src/pygui/ISC/Tabs/components/RailActionButton.qml

@@ -12,6 +12,9 @@ Rectangle {
     property string label: ""
     property string iconSource: ""
     property bool destructive: false
+    // Set true to show the button as "active" (e.g. a one-shot toggle
+    // that's mid-operation), independent of hover/press state.
+    property bool toggled: false
     property color _textColor: !root.enabled ? Theme.sideMutedText
         : root.destructive ? Theme.statusErrorColor
         : Theme.headingColor
@@ -20,7 +23,7 @@ Rectangle {
 
     implicitHeight: Theme.sideButtonHeight
     radius: 8
-    color: mouseArea.containsMouse || mouseArea.pressed
+    color: root.toggled || mouseArea.containsMouse || mouseArea.pressed
         ? Theme.sideActiveBackground : "transparent"
     border.width: 0
 

src/pygui/ISC/Tabs/components/ReadoutPanel.qml

@@ -1,61 +1,26 @@
 import QtQuick
 import QtQuick.Controls
+import QtQuick.Dialogs
 import QtQuick.Layouts
 import ISC
 
 // ===== Readout Panel =====
-// Right-rail panel with three bordered sections: READOUT, DISPLAY, THRESHOLDS.
-// Cards match the left-rail SOURCE / CONNECTION FLOW style.
+// Right-rail panel with three bento-tile sections: READOUT, DISPLAY,
+// THRESHOLDS. Uses the same PanelBox / SectionTitle / ReadoutStat /
+// PanelCheckBox / PanelSlider components as the Data tab's
+// ComparisonSidePanel, so both right rails share one visual language.
 ColumnLayout {
+    id: root
     spacing: 6
     property var s: streamController.stats
     property alias showLabels: labelsToggle.checked
+    property alias showExtremes: extremesToggle.checked
     property alias heatmapBlend: heatmapSlider.value
     property alias showThickness: thicknessToggle.checked
+    property bool hasThicknessData: false
 
-    component PanelCheckBox: CheckBox {
-        id: toggle
-        indicator: Rectangle {
-            implicitWidth: 18
-            implicitHeight: 18
-            x: toggle.leftPadding
-            y: parent.height / 2 - height / 2
-            radius: Theme.radiusXs
-            color: toggle.checked ? Theme.primaryAccent : "transparent"
-            border.width: Theme.borderThin
-            border.color: toggle.checked ? Theme.primaryAccent : Theme.fieldBorder
-
-            Behavior on color {
-                ColorAnimation { duration: Theme.durationFast }
-            }
-            Behavior on border.color {
-                ColorAnimation { duration: Theme.durationFast }
-            }
-
-            Text {
-                anchors.centerIn: parent
-                text: "✓"
-                font.pixelSize: Theme.fontSm
-                font.bold: true
-                color: Theme.panelBackground
-                opacity: toggle.checked ? 1.0 : 0.0
-                Behavior on opacity {
-                    NumberAnimation { duration: Theme.durationFast }
-                }
-                verticalAlignment: Text.AlignVCenter
-                horizontalAlignment: Text.AlignHCenter
-            }
-        }
-
-        contentItem: Text {
-            text: toggle.text
-            color: Theme.headingColor
-            font.family: Theme.uiFontFamily
-            verticalAlignment: Text.AlignVCenter
-            leftPadding: toggle.indicator.width + toggle.spacing
-            font.pixelSize: toggle.font.pixelSize || Theme.fontXs
-        }
-    }
+    signal exportRequested(string filePath, string extra)
+    signal thicknessFileChosen(string filePath)
 
     component BadgePill: Rectangle {
         implicitWidth: badgeLabel.implicitWidth + 10
@@ -75,279 +40,127 @@ ColumnLayout {
         }
     }
 
-    Rectangle {
+    StreamControlPanel {
         Layout.fillWidth: true
-        implicitHeight: readoutCard.implicitHeight + 24
-        color: Theme.sidePanelBackground
-        radius: Theme.sidePanelRadius
-        border.color: Theme.sideBorder
-        border.width: 1
+        onExportRequested: function(filePath, extra) {
+            root.exportRequested(filePath, extra);
+        }
+    }
+
+    // ── READOUT ─────────────────────────────────────────────────────
+    PanelBox {
+        Layout.fillWidth: true
+        Layout.preferredHeight: readoutCol.implicitHeight + 24
 
         ColumnLayout {
-            id: readoutCard
-            anchors {
-                left: parent.left
-                right: parent.right
-                top: parent.top
-                topMargin: 12
-            }
-            spacing: 0
+            id: readoutCol
+            anchors.fill: parent
+            anchors.margins: 12
+            spacing: 8
 
-            // Header Inside the Box
-            Label {
-                text: "READOUT"
-                color: Theme.sideMutedText
-                font.family: Theme.uiFontFamily
-                font.pixelSize: Theme.fontXs
-                font.letterSpacing: 1.5
-                font.bold: true
-                Layout.leftMargin: 14
-                Layout.rightMargin: 14
-                Layout.topMargin: 2
-                Layout.bottomMargin: 10
-            }
+            SectionTitle { text: "READOUT" }
 
-            // Min Temp Row
-            RowLayout {
-                Layout.fillWidth: true
-                Layout.leftMargin: 14
-                Layout.rightMargin: 14
-                Layout.preferredHeight: 32
-                Label {
-                    text: "MIN TEMP"
-                    color: Theme.sideMutedText
-                    font.family: Theme.uiFontFamily
-                    font.pixelSize: Theme.fontXs
-                    font.bold: true
-                }
-                Item { Layout.fillWidth: true }
-                RowLayout {
-                    spacing: 4
-                    Label {
-                        text: s.min !== undefined ? s.min : "—"
-                        color: Theme.sensorLow
-                        font.family: Theme.codeFontFamily
-                        font.pixelSize: Theme.fontMd
-                        font.bold: true
-                    }
-                    Label {
-                        visible: (s.minIndex !== undefined) && s.minIndex >= 0
-                        text: "#" + (s.minIndex !== undefined ? s.minIndex : "")
-                        color: Theme.sideMutedText
-                        font.family: Theme.uiFontFamily
-                        font.pixelSize: Theme.font2xs
-                        Layout.alignment: Qt.AlignBottom
-                        bottomPadding: 3
-                    }
-                }
+            ReadoutStat {
+                label: "Min Temp"
+                value: s.min !== undefined
+                    ? s.min + ((s.minIndex !== undefined && s.minIndex >= 0) ? "  #" + s.minIndex : "")
+                    : "—"
+                valueColor: Theme.sensorLow
             }
-
-            Rectangle {
-                Layout.fillWidth: true
-                height: 1
-                color: Theme.cardBorder
+            ReadoutStat {
+                label: "Max Temp"
+                value: s.max !== undefined
+                    ? s.max + ((s.maxIndex !== undefined && s.maxIndex >= 0) ? "  #" + s.maxIndex : "")
+                    : "—"
+                valueColor: Theme.sensorHigh
             }
-
-            // Max Temp Row
-            RowLayout {
-                Layout.fillWidth: true
-                Layout.leftMargin: 14
-                Layout.rightMargin: 14
-                Layout.preferredHeight: 32
-                Label {
-                    text: "MAX TEMP"
-                    color: Theme.sideMutedText
-                    font.family: Theme.uiFontFamily
-                    font.pixelSize: Theme.fontXs
-                    font.bold: true
-                }
-                Item { Layout.fillWidth: true }
-                RowLayout {
-                    spacing: 4
-                    Label {
-                        text: s.max !== undefined ? s.max : "—"
-                        color: Theme.sensorHigh
-                        font.family: Theme.codeFontFamily
-                        font.pixelSize: Theme.fontMd
-                        font.bold: true
-                    }
-                    Label {
-                        visible: (s.maxIndex !== undefined) && s.maxIndex >= 0
-                        text: "#" + (s.maxIndex !== undefined ? s.maxIndex : "")
-                        color: Theme.sideMutedText
-                        font.family: Theme.uiFontFamily
-                        font.pixelSize: Theme.font2xs
-                        Layout.alignment: Qt.AlignBottom
-                        bottomPadding: 3
-                    }
-                }
+            ReadoutStat {
+                label: "Diff"
+                value: s.diff !== undefined ? s.diff : "—"
+                valueColor: Theme.diffAccent
             }
-
-            Rectangle {
-                Layout.fillWidth: true
-                height: 1
-                color: Theme.cardBorder
+            ReadoutStat {
+                label: "Average"
+                value: s.avg !== undefined ? s.avg : "—"
             }
-
-            // Differential Row
-            RowLayout {
-                Layout.fillWidth: true
-                Layout.leftMargin: 14
-                Layout.rightMargin: 14
-                Layout.preferredHeight: 32
-                Label {
-                    text: "DIFF"
-                    color: Theme.sideMutedText
-                    font.family: Theme.uiFontFamily
-                    font.pixelSize: Theme.fontXs
-                    font.bold: true
-                }
-                Item { Layout.fillWidth: true }
-                Label {
-                    text: s.diff !== undefined ? s.diff : "—"
-                    color: Theme.isDarkMode ? "#A78BFA" : "#8B5CF6"
-                    font.family: Theme.codeFontFamily
-                    font.pixelSize: Theme.fontMd
-                    font.bold: true
-                }
+            ReadoutStat {
+                label: "Sigma (Σ)"
+                value: s.sigma !== undefined ? s.sigma : "—"
             }
-
-            Rectangle {
-                Layout.fillWidth: true
-                height: 1
-                color: Theme.cardBorder
+            ReadoutStat {
+                label: "3Σ Value"
+                value: s.threeSigma !== undefined ? s.threeSigma : "—"
             }
-
-            // Average Row
-            RowLayout {
-                Layout.fillWidth: true
-                Layout.leftMargin: 14
-                Layout.rightMargin: 14
-                Layout.preferredHeight: 32
-                Label {
-                    text: "AVERAGE"
-                    color: Theme.sideMutedText
-                    font.family: Theme.uiFontFamily
-                    font.pixelSize: Theme.fontXs
-                    font.bold: true
-                }
-                Item { Layout.fillWidth: true }
-                Label {
-                    text: s.avg !== undefined ? s.avg : "—"
-                    color: Theme.headingColor
-                    font.family: Theme.codeFontFamily
-                    font.pixelSize: Theme.fontMd
-                    font.bold: true
-                }
+            ReadoutStat {
+                visible: s.ecMinDelta !== undefined
+                label: "E-C Δ Min"
+                value: s.ecMinDelta !== undefined
+                    ? s.ecMinDelta.toFixed(2) + " (#" + s.ecMinEdgeIndex + "→#" + s.ecMinCenterIndex + ")"
+                    : "—"
             }
-
-            Rectangle {
-                Layout.fillWidth: true
-                height: 1
-                color: Theme.cardBorder
-            }
-
-            // Sigma Row
-            RowLayout {
-                Layout.fillWidth: true
-                Layout.leftMargin: 14
-                Layout.rightMargin: 14
-                Layout.preferredHeight: 32
-                Label {
-                    text: "SIGMA (Σ)"
-                    color: Theme.sideMutedText
-                    font.family: Theme.uiFontFamily
-                    font.pixelSize: Theme.fontXs
-                    font.bold: true
-                }
-                Item { Layout.fillWidth: true }
-                Label {
-                    text: s.sigma !== undefined ? s.sigma : "—"
-                    color: Theme.headingColor
-                    font.family: Theme.codeFontFamily
-                    font.pixelSize: Theme.fontMd
-                    font.bold: true
-                }
-            }
-
-            Rectangle {
-                Layout.fillWidth: true
-                height: 1
-                color: Theme.cardBorder
-            }
-
-            // 3-Sigma Row
-            RowLayout {
-                Layout.fillWidth: true
-                Layout.leftMargin: 14
-                Layout.rightMargin: 14
-                Layout.preferredHeight: 32
-                Label {
-                    text: "3Σ VALUE"
-                    color: Theme.sideMutedText
-                    font.family: Theme.uiFontFamily
-                    font.pixelSize: Theme.fontXs
-                    font.bold: true
-                }
-                Item { Layout.fillWidth: true }
-                Label {
-                    text: s.threeSigma !== undefined ? s.threeSigma : "—"
-                    color: Theme.headingColor
-                    font.family: Theme.codeFontFamily
-                    font.pixelSize: Theme.fontMd
-                    font.bold: true
-                }
+            ReadoutStat {
+                visible: s.ecMaxDelta !== undefined
+                label: "E-C Δ Max"
+                value: s.ecMaxDelta !== undefined
+                    ? s.ecMaxDelta.toFixed(2) + " (#" + s.ecMaxEdgeIndex + "→#" + s.ecMaxCenterIndex + ")"
+                    : "—"
             }
         }
     }
 
-    Rectangle {
+    // ── DISPLAY ─────────────────────────────────────────────────────
+    PanelBox {
         Layout.fillWidth: true
-        implicitHeight: displayCard.implicitHeight + 24
-        color: Theme.sidePanelBackground
-        radius: Theme.sidePanelRadius
-        border.color: Theme.sideBorder
-        border.width: 1
+        Layout.preferredHeight: displayCard.implicitHeight + 24
 
         ColumnLayout {
             id: displayCard
-            anchors {
-                left: parent.left
-                right: parent.right
-                top: parent.top
-                margins: 12
-            }
+            anchors.fill: parent
+            anchors.margins: 12
             spacing: 8
 
-            Label {
-                text: "DISPLAY"
-                color: Theme.sideMutedText
-                font.family: Theme.uiFontFamily
-                font.pixelSize: Theme.fontXs
-                font.letterSpacing: 1.5
-                font.bold: true
-                Layout.bottomMargin: 4
-            }
+            SectionTitle { text: "DISPLAY" }
 
             PanelCheckBox {
                 id: thicknessToggle
                 text: "Show Thickness"
                 checked: false
-                font.pixelSize: Theme.fontXs
+                font.pixelSize: Theme.fontSm
+                // First check with no data prompts for the customer CSV;
+                // unchecking only hides the overlay, data stays loaded.
+                onToggled: {
+                    if (checked && !root.hasThicknessData)
+                        thicknessDialog.open();
+                }
+            }
+
+            FileDialog {
+                id: thicknessDialog
+                title: "Select Thickness Data File"
+                nameFilters: ["CSV files (*.csv)"]
+                onAccepted: root.thicknessFileChosen(String(selectedFile).replace(/^file:\/\//, ""))
+                onRejected: thicknessToggle.checked = false
             }
 
             PanelCheckBox {
                 id: labelsToggle
                 text: "Labels"
                 checked: true
-                font.pixelSize: Theme.fontXs
+                font.pixelSize: Theme.fontSm
+            }
+
+            PanelCheckBox {
+                id: extremesToggle
+                text: "Highlight Min/Max"
+                checked: true
+                font.pixelSize: Theme.fontSm
             }
 
             PanelCheckBox {
                 id: clusterAverageToggle
                 text: "Average Clusters"
                 checked: streamController.clusterAveragingEnabled
-                font.pixelSize: Theme.fontXs
+                font.pixelSize: Theme.fontSm
                 onCheckedChanged: streamController.clusterAveragingEnabled = checked
             }
 
@@ -363,35 +176,25 @@ ColumnLayout {
                 Label {
                     text: "Heatmap"
                     color: Theme.bodyColor
-                    font.pixelSize: Theme.fontXs
+                    font.pixelSize: Theme.fontSm
                     Layout.preferredWidth: 52
                 }
-                Slider {
+                PanelSlider {
                     id: heatmapSlider
                     from: 0
                     to: 1
                     value: 0
                     Layout.fillWidth: true
-                    ToolTip.visible: hovered
-                    ToolTip.text: Math.round(value * 100) + "%"
 
-                    handle: Rectangle {
-                        x: heatmapSlider.leftPadding + heatmapSlider.visualPosition * (heatmapSlider.availableWidth - width)
-                        y: heatmapSlider.topPadding + heatmapSlider.availableHeight / 2 - height / 2
-                        implicitWidth: 18
-                        implicitHeight: 18
-                        radius: 9
-                        color: Theme.primaryAccent
-                        scale: heatmapSlider.pressed ? 1.15 : 1.0
-                        Behavior on scale {
-                            NumberAnimation { duration: Theme.durationFast; easing.type: Theme.easeStandard }
-                        }
+                    AppToolTip {
+                        visible: heatmapSlider.hovered
+                        text: Math.round(heatmapSlider.value * 100) + "%"
                     }
                 }
                 Label {
                     text: Math.round(heatmapSlider.value * 100) + "%"
                     color: Theme.bodyColor
-                    font.pixelSize: Theme.fontXs
+                    font.pixelSize: Theme.fontSm
                     font.weight: Font.Medium
                     Layout.preferredWidth: 32
                     horizontalAlignment: Text.AlignRight
@@ -400,38 +203,23 @@ ColumnLayout {
         }
     }
 
-    Rectangle {
+    // ── THRESHOLDS ──────────────────────────────────────────────────
+    PanelBox {
         Layout.fillWidth: true
-        implicitHeight: thresholdCard.implicitHeight + 24
-        color: Theme.sidePanelBackground
-        radius: Theme.sidePanelRadius
-        border.color: Theme.sideBorder
-        border.width: 1
+        Layout.preferredHeight: thresholdCard.implicitHeight + 24
 
         ColumnLayout {
             id: thresholdCard
-            anchors {
-                left: parent.left
-                right: parent.right
-                top: parent.top
-                margins: 12
-            }
+            anchors.fill: parent
+            anchors.margins: 12
             spacing: 6
 
-            Label {
-                text: "THRESHOLDS"
-                color: Theme.sideMutedText
-                font.family: Theme.uiFontFamily
-                font.pixelSize: Theme.fontXs
-                font.letterSpacing: 1.5
-                font.bold: true
-                Layout.bottomMargin: 4
-            }
+            SectionTitle { text: "THRESHOLDS" }
 
             Label {
                 text: "Set Point (°C)"
                 color: Theme.bodyColor
-                font.pixelSize: Theme.fontXs
+                font.pixelSize: Theme.fontSm
             }
             TextField {
                 id: spField
@@ -461,7 +249,7 @@ ColumnLayout {
             Label {
                 text: "Margin (±°C)"
                 color: Theme.bodyColor
-                font.pixelSize: Theme.fontXs
+                font.pixelSize: Theme.fontSm
             }
             TextField {
                 id: mgField
@@ -492,7 +280,7 @@ ColumnLayout {
                 id: autoCheck
                 text: "Auto range  (mean ± 1σ)"
                 checked: true
-                font.pixelSize: Theme.fontXs
+                font.pixelSize: Theme.fontSm
                 onCheckedChanged: pushThresholds()
             }
         }

src/pygui/ISC/Tabs/components/ReadoutStat.qml

@@ -0,0 +1,39 @@
+import QtQuick
+import QtQuick.Controls
+import QtQuick.Layouts
+import ISC
+
+// Small labeled value tile — DTW readout panel, scrubber readout, and any
+// other compact label/value stat display share this one shape.
+Rectangle {
+    id: readoutStat
+    property string label
+    property string value
+    property color valueColor: Theme.headingColor
+    Layout.fillWidth: true
+    implicitHeight: 52
+    radius: Theme.radiusSm
+    color: Theme.subtleSectionBackground
+    border.color: Theme.cardBorder
+    border.width: 1
+
+    ColumnLayout {
+        anchors.fill: parent
+        anchors.margins: 8
+        spacing: 2
+        Label {
+            text: readoutStat.label.toUpperCase()
+            font.pixelSize: Theme.fontXs
+            font.bold: true
+            font.letterSpacing: 0.2
+            color: Theme.sideMutedText
+        }
+        Label {
+            text: readoutStat.value
+            font.pixelSize: Theme.fontLg
+            font.bold: true
+            font.family: Theme.codeFontFamily
+            color: readoutStat.valueColor
+        }
+    }
+}

src/pygui/ISC/Tabs/components/ReplaceSensorDialog.qml

@@ -10,6 +10,10 @@ Dialog {
     standardButtons: Dialog.NoButton
     width: 300
 
+    // Anchor to the top-left of the window instead of the default centered position.
+    x: 24
+    y: 24
+
     // called by WaferMapView's TapHandler
     property int sensorIndex: -1
     property string sensorLabel: ""
@@ -60,7 +64,7 @@ Dialog {
                     id: overrideTag
                     anchors.centerIn: parent
                     text: "OVERRIDE"
-                    color: "white"
+                    color: Theme.statusBadgeText
                     font.pixelSize: Theme.fontXs
                     font.bold: true
                     font.letterSpacing: 1

src/pygui/ISC/Tabs/components/RunChart.qml

@@ -0,0 +1,135 @@
+import QtQuick
+import QtQuick.Controls
+import QtQuick.Layouts
+import ISC
+import ISC.Wafer
+
+// ===== Run Chart =====
+// Zoomable whole-run multi-sensor chart (C# parity: PopupChartForm.cs).
+// Lives in the Graph tab. Mouse wheel zooms around the cursor, drag pans;
+// the strip below shows the aggregate min/max/avg over the *visible* range
+// (not the whole run), matching PopupChartForm's recalc_stats. Cursor/
+// playhead tracking is out of scope — see specs/plans/2026-07-10-popup-chart.md
+// and docs/adr/0004-graphquickitem-viewport-for-replay-chart.md.
+Item {
+    id: root
+
+    property alias sensorNames: chart.sensorNames
+    property alias seriesData: chart.seriesData
+    property alias title: chart.title
+
+    ColumnLayout {
+        anchors.fill: parent
+        spacing: 8
+
+        Item {
+            Layout.fillWidth: true
+            Layout.fillHeight: true
+
+            GraphQuickItem {
+                id: chart
+                anchors.fill: parent
+                showMinMaxMarkers: true
+                xLabel: "Measurement Interval"
+                yLabel: "Temperature (°C)"
+            }
+
+            MouseArea {
+                id: interaction
+                anchors.fill: parent
+                acceptedButtons: Qt.LeftButton
+                property real lastX: 0
+
+                onWheel: function(wheel) {
+                    var frac = Math.max(0, Math.min(1, wheel.x / width));
+                    var factor = wheel.angleDelta.y > 0 ? 0.8 : 1.25;
+                    chart.zoomAtFraction(frac, factor);
+                    wheel.accepted = true;
+                }
+                onPressed: function(mouse) {
+                    lastX = mouse.x;
+                }
+                onPositionChanged: function(mouse) {
+                    if (pressed && width > 0) {
+                        chart.panByFraction(-(mouse.x - lastX) / width);
+                        lastX = mouse.x;
+                    }
+                }
+            }
+        }
+
+        // ── Min/Max/Avg readout strip + Reset Zoom ─────────────────────
+        RowLayout {
+            Layout.fillWidth: true
+            spacing: 16
+
+            Label {
+                text: "Min:"
+                color: Theme.sensorLow
+                font.family: Theme.uiFontFamily
+                font.pixelSize: Theme.fontSm
+                font.weight: Font.Medium
+            }
+            Label {
+                text: chart.viewMin.toFixed(2) + (chart.viewMinSensor ? "  (" + chart.viewMinSensor + ")" : "")
+                color: Theme.headingColor
+                font.family: Theme.codeFontFamily
+                font.pixelSize: Theme.fontSm
+            }
+
+            Label {
+                text: "Max:"
+                color: Theme.sensorHigh
+                font.family: Theme.uiFontFamily
+                font.pixelSize: Theme.fontSm
+                font.weight: Font.Medium
+            }
+            Label {
+                text: chart.viewMax.toFixed(2) + (chart.viewMaxSensor ? "  (" + chart.viewMaxSensor + ")" : "")
+                color: Theme.headingColor
+                font.family: Theme.codeFontFamily
+                font.pixelSize: Theme.fontSm
+            }
+
+            Label {
+                text: "Avg:"
+                color: Theme.sideMutedText
+                font.family: Theme.uiFontFamily
+                font.pixelSize: Theme.fontSm
+                font.weight: Font.Medium
+            }
+            Label {
+                text: chart.viewAvg.toFixed(2)
+                color: Theme.headingColor
+                font.family: Theme.codeFontFamily
+                font.pixelSize: Theme.fontSm
+            }
+
+            Item { Layout.fillWidth: true }
+
+            Button {
+                id: resetZoomBtn
+                implicitHeight: 32
+                hoverEnabled: true
+                text: "Reset Zoom"
+                font.family: Theme.uiFontFamily
+                font.pixelSize: Theme.fontSm
+                font.weight: Font.Medium
+                background: Rectangle {
+                    radius: Theme.radiusSm
+                    color: resetZoomBtn.pressed ? Theme.transportButtonHover : Theme.transportButtonBg
+                    border.color: Theme.sideBorder
+                    border.width: 1
+                }
+                contentItem: Text {
+                    text: resetZoomBtn.text
+                    color: Theme.headingColor
+                    font: resetZoomBtn.font
+                    horizontalAlignment: Text.AlignHCenter
+                    verticalAlignment: Text.AlignVCenter
+                }
+                onClicked: chart.resetZoom()
+            }
+        }
+    }
+}

src/pygui/ISC/Tabs/components/SectionTitle.qml

@@ -0,0 +1,12 @@
+import QtQuick
+import QtQuick.Controls
+import ISC
+
+// Uppercase card heading — shared by the Data tab cards.
+Label {
+    font.family: Theme.uiFontFamily
+    font.pixelSize: Theme.fontSm
+    font.letterSpacing: 1.5
+    font.bold: true
+    color: Theme.sideMutedText
+}

src/pygui/ISC/Tabs/components/SelectFileDialog.qml

@@ -1,5 +1,6 @@
 import QtQuick
 import QtQuick.Controls
+import QtQuick.Controls.impl
 import QtQuick.Layouts
 import Qt.labs.qmlmodels
 import ISC
@@ -181,10 +182,17 @@ Dialog {
             anchors.verticalCenter: parent.verticalCenter
             anchors.right: parent.right
             anchors.rightMargin: 12
-            text: "✕"
             implicitWidth: 32
             implicitHeight: 32
             onClicked: root.close()
+            contentItem: IconImage {
+                source: "../icons/x.svg"
+                width: 14; height: 14
+                sourceSize.width: 14
+                sourceSize.height: 14
+                color: Theme.buttonNeutralText
+                anchors.centerIn: parent
+            }
         }
     }
 

src/pygui/ISC/Tabs/components/SourcePanel.qml

@@ -46,24 +46,9 @@ ColumnLayout {
                 csvEditorDialog.open();
             }
 
-            ToolTip {
-                id: editTooltip
+            AppToolTip {
                 visible: editBtn.hovered
                 text: "Edit"
-                delay: 400
-                font.pixelSize: Theme.fontXs
-                font.family: Theme.uiFontFamily
-                contentItem: Text {
-                    text: editTooltip.text
-                    color: Theme.headingColor
-                    font: editTooltip.font
-                }
-                background: Rectangle {
-                    color: Theme.cardBackground
-                    border.color: Theme.sideBorder
-                    border.width: 1
-                    radius: Theme.radiusXs
-                }
             }
         }
 
@@ -84,24 +69,9 @@ ColumnLayout {
             }
             onClicked: file_browser.refreshFiles()
 
-            ToolTip {
-                id: refreshTooltip
+            AppToolTip {
                 visible: refreshBtn.hovered
                 text: "Refresh"
-                delay: 400
-                font.pixelSize: Theme.fontXs
-                font.family: Theme.uiFontFamily
-                contentItem: Text {
-                    text: refreshTooltip.text
-                    color: Theme.headingColor
-                    font: refreshTooltip.font
-                }
-                background: Rectangle {
-                    color: Theme.cardBackground
-                    border.color: Theme.sideBorder
-                    border.width: 1
-                    radius: Theme.radiusXs
-                }
             }
         }
     }
@@ -122,10 +92,12 @@ ColumnLayout {
         }
         contentItem: RowLayout {
             spacing: 6
-            Label {
-                text: "▤"
+            IconImage {
+                source: "../icons/folder.svg"
+                width: 14; height: 14
+                sourceSize.width: 14
+                sourceSize.height: 14
                 color: Theme.bodyColor
-                font.pixelSize: Theme.fontSm
             }
             Label {
                 text: file_browser.currentDirectory.split("/").pop() || file_browser.currentDirectory
@@ -188,16 +160,52 @@ ColumnLayout {
                 return (modelData.baseName + modelData.waferType + modelData.date).toLowerCase().indexOf(q) >= 0;
             }
 
-            // Active only in review mode; no highlight during live streaming
-            readonly property bool isActive: streamController.mode === "review" && streamController.loadedFile !== "" && modelData.fileName === streamController.loadedFile
+            readonly property var dataTab: {
+                try {
+                    return (root.selectedTabIndex === 1 && dataTabLoader.item) ? dataTabLoader.item : null;
+                } catch (e) { return null; }
+            }
+
+            // Run A's effective file: the master file when "Compare vs Master
+            // File" is toggled on, otherwise the manually selected file.
+            readonly property string effectiveRunAFile: fileItem.dataTab
+                ? (fileItem.dataTab.useMasterFile ? fileItem.dataTab.masterFileForRunB : fileItem.dataTab.compareFileA)
+                : ""
+            readonly property bool isRunA: fileItem.dataTab !== null
+                && fileItem.effectiveRunAFile !== "" && modelData.fileName === fileItem.effectiveRunAFile
+            readonly property bool isRunB: fileItem.dataTab !== null
+                && modelData.fileName === fileItem.dataTab.compareFileB
+
+            // Active highlight logic: on Data tab, highlight the Run A/Run B files (or the
+            // resolved master file standing in for Run A); otherwise highlight loadedFile (Map tab).
+            readonly property bool isActive: fileItem.dataTab !== null
+                ? (fileItem.isRunA || fileItem.isRunB)
+                : (streamController.mode === "review" && streamController.loadedFile !== "" && modelData.fileName === streamController.loadedFile)
+
+            // A file registered as any family's master in Settings → Master Files.
+            readonly property bool isMasterFile: {
+                var m = settingsModel.masters
+                for (var fam in m) {
+                    if (m[fam] && m[fam] === modelData.fileName) return true
+                }
+                return false
+            }
+
+            readonly property bool isLiveFile: (modelData.baseName || "").toLowerCase().indexOf("live") >= 0
+            readonly property bool liveFileBlocked: root.selectedTabIndex === 1 && isLiveFile
 
             visible: matchesFilter
             height: matchesFilter ? implicitHeight : 0
+            enabled: !liveFileBlocked
+            opacity: liveFileBlocked ? 0.45 : 1.0
+            Behavior on opacity {
+                NumberAnimation { duration: Theme.durationFast }
+            }
 
             onClicked: streamController.loadFile(modelData.fileName)
 
             background: Rectangle {
-                color: fileItem.isActive ? Qt.rgba(1, 1, 1, 0.06) : fileItem.hovered ? Qt.rgba(1, 1, 1, 0.04) : "transparent"
+                color: fileItem.isActive ? Theme.listActiveBackground : fileItem.hovered ? Theme.listHoverBackground : "transparent"
                 radius: Theme.radiusSm
                 Behavior on color {
                     ColorAnimation { duration: Theme.durationFast }
@@ -216,13 +224,15 @@ ColumnLayout {
                         bottomMargin: 5
                     }
                     color: {
+                        if (fileItem.isRunA) return Theme.primaryAccent;
+                        if (fileItem.isRunB) return Theme.themeSkill;
                         var t = modelData.waferType;
                         if (t === "A" || t === "E" || t === "P")
-                            return "#3B82F6";
+                            return Theme.familyBlueAccent;
                         if (t === "B" || t === "C" || t === "D")
-                            return "#10B981";
+                            return Theme.familyGreenAccent;
                         if (t === "Z")
-                            return "#8B5CF6";
+                            return Theme.familyVioletAccent;
                         return Theme.headingColor;
                     }
                 }
@@ -242,19 +252,46 @@ ColumnLayout {
                     color: {
                         var t = modelData.waferType;
                         if (t === "A" || t === "E" || t === "P")
-                            return "#1D4ED8";
+                            return Theme.familyBlueFill;
                         if (t === "B" || t === "C" || t === "D")
-                            return "#065F46";
+                            return Theme.familyGreenFill;
                         if (t === "Z")
-                            return "#7C3AED";
-                        return "#374151";
+                            return Theme.familyVioletFill;
+                        return Theme.familyNeutralFill;
                     }
                     Label {
                         anchors.centerIn: parent
                         text: modelData.waferType || "?"
                         font.pixelSize: Theme.fontMd
                         font.weight: Font.Bold
-                        color: "#FFFFFF"
+                        color: Theme.textOnColor
+                    }
+
+                    // Recording indicator dot — distinguishes a live-recorded CSV
+                    // (SessionController.startRecording) from a read-memory dump
+                    // (DeviceController.parseAndSaveData).
+                    Rectangle {
+                        visible: modelData.isRecording === true
+                        width: 10
+                        height: 10
+                        radius: 5
+                        color: Theme.recordColor
+                        border.color: Theme.subtleSectionBackground
+                        border.width: 1.5
+                        anchors.top: parent.top
+                        anchors.right: parent.right
+                        anchors.topMargin: -2
+                        anchors.rightMargin: -2
+                    }
+
+                    // Accent ring — this file is registered as a master (Settings → Master Files).
+                    Rectangle {
+                        visible: fileItem.isMasterFile
+                        anchors.fill: parent
+                        radius: parent.radius
+                        color: "transparent"
+                        border.color: Theme.primaryAccent
+                        border.width: 2
                     }
                 }
 
@@ -263,14 +300,57 @@ ColumnLayout {
                     spacing: 1
                     Layout.fillWidth: true
 
-                    // Primary: wafer type + serial number
-                    Label {
-                        text: modelData.serialNumber ? (modelData.waferType + modelData.serialNumber) : modelData.baseName
-                        color: Theme.headingColor
-                        font.pixelSize: Theme.fontMd
-                        font.weight: Font.Bold
-                        elide: Text.ElideRight
+                    // Primary: wafer type + serial number, plus a REC badge for recordings
+                    RowLayout {
                         Layout.fillWidth: true
+                        spacing: 6
+
+                        Label {
+                            text: modelData.serialNumber ? (modelData.waferType + modelData.serialNumber) : modelData.baseName
+                            color: Theme.headingColor
+                            font.pixelSize: Theme.fontMd
+                            font.weight: Font.Bold
+                            elide: Text.ElideRight
+                            Layout.fillWidth: true
+                        }
+
+                        Rectangle {
+                            visible: modelData.isRecording === true
+                            radius: 4
+                            color: Qt.alpha(Theme.recordColor, 0.18)
+                            implicitWidth: recLabel.implicitWidth + 10
+                            implicitHeight: recLabel.implicitHeight + 4
+                            Layout.alignment: Qt.AlignVCenter
+
+                            Label {
+                                id: recLabel
+                                anchors.centerIn: parent
+                                text: "REC"
+                                color: Theme.recordColor
+                                font.pixelSize: Theme.font2xs
+                                font.bold: true
+                                font.letterSpacing: 0.6
+                            }
+                        }
+
+                        Rectangle {
+                            visible: fileItem.isMasterFile
+                            radius: 4
+                            color: Qt.alpha(Theme.primaryAccent, 0.18)
+                            implicitWidth: masterLabel.implicitWidth + 10
+                            implicitHeight: masterLabel.implicitHeight + 4
+                            Layout.alignment: Qt.AlignVCenter
+
+                            Label {
+                                id: masterLabel
+                                anchors.centerIn: parent
+                                text: "MASTER"
+                                color: Theme.primaryAccent
+                                font.pixelSize: Theme.font2xs
+                                font.bold: true
+                                font.letterSpacing: 0.6
+                            }
+                        }
                     }
 
                     // Secondary: date · time

src/pygui/ISC/Tabs/components/SplitDialog.qml

@@ -0,0 +1,359 @@
+import QtQuick
+import QtQuick.Layouts
+import QtQuick.Controls
+import QtQuick.Dialogs
+import ISC
+
+// ===== Split Dialog (Threshold Segmentation) =====
+// Modal popup for segmenting temperature profile into Ramp/Soak/Cool phases.
+// Backend: splitter.segment_profile() returns list of DataSegment objects.
+
+Popup {
+    id: root
+    modal: true
+    dim: true
+    closePolicy: Popup.CloseOnEscape | Popup.CloseOnPressOutside
+    width: Math.min(parent.width - 100, 800)
+    height: Math.min(parent.height - 100, 600)
+    anchors.centerIn: Overlay.overlay
+
+    property real threshold: 40.0
+    property bool segmenting: false
+    property var segments: []
+    property string currentFile: streamController.loadedFile || ""
+
+    background: Rectangle {
+        radius: Theme.radiusMd
+        color: Theme.cardBackground
+        border.color: Theme.cardBorder
+        border.width: 1
+    }
+
+    ColumnLayout {
+        anchors.fill: parent
+        anchors.margins: 20
+        spacing: 16
+
+        // ── Header ────────────────────────────────────────────────
+        RowLayout {
+            Layout.fillWidth: true
+            spacing: 10
+
+            Label {
+                text: "SPLIT DATA"
+                font.pixelSize: Theme.fontLg
+                font.bold: true
+                color: Theme.headingColor
+                Layout.fillWidth: true
+            }
+
+            Button {
+                text: "\u2715"
+                flat: true
+                Layout.preferredWidth: 32
+                Layout.preferredHeight: 32
+                onClicked: root.close()
+
+                background: Rectangle {
+                    radius: Theme.radiusXs
+                    color: parent.hovered ? Theme.buttonNeutralHover : "transparent"
+                }
+                contentItem: Label {
+                    text: parent.text
+                    color: Theme.bodyColor
+                    horizontalAlignment: Text.AlignHCenter
+                    verticalAlignment: Text.AlignVCenter
+                }
+            }
+        }
+
+        // ── Threshold Input ───────────────────────────────────────
+        RowLayout {
+            Layout.fillWidth: true
+            spacing: 16
+
+            ColumnLayout {
+                Layout.fillWidth: true
+                spacing: 4
+
+                Label {
+                    text: "THRESHOLD TEMPERATURE (°C)"
+                    color: Theme.sideMutedText
+                    font.pixelSize: Theme.fontSm
+                    font.bold: true
+                    font.letterSpacing: 1.0
+                }
+
+                RowLayout {
+                    Layout.fillWidth: true
+                    spacing: 8
+
+                    SpinBox {
+                        id: thresholdSpin
+                        from: 0
+                        to: 200
+                        value: root.threshold
+                        stepSize: 1
+                        editable: true
+                        Layout.fillWidth: true
+                        background: Rectangle {
+                            color: Theme.fieldBackground
+                            border.color: Theme.cardBorder
+                            border.width: 1
+                            radius: Theme.radiusSm
+                        }
+                    }
+
+                    Label {
+                        text: "°C"
+                        color: Theme.bodyColor
+                        font.pixelSize: Theme.fontMd
+                        verticalAlignment: Text.AlignVCenter
+                    }
+                }
+            }
+
+            ColumnLayout {
+                Layout.fillWidth: true
+                spacing: 4
+
+                Label {
+                    text: "SESSION CSV"
+                    color: Theme.sideMutedText
+                    font.pixelSize: Theme.fontSm
+                    font.bold: true
+                    font.letterSpacing: 1.0
+                }
+
+                Label {
+                    Layout.fillWidth: true
+                    text: root.currentFile !== ""
+                        ? root.currentFile.split("/").pop()
+                        : "No file loaded"
+                    color: root.currentFile !== "" ? Theme.bodyColor : Theme.sideMutedText
+                    font.pixelSize: Theme.fontSm
+                    elide: Text.ElideMiddle
+                }
+            }
+        }
+
+        // ── Split Button ──────────────────────────────────────────
+        RowLayout {
+            Layout.fillWidth: true
+            spacing: 10
+
+            Button {
+                id: splitBtn
+                text: "SPLIT"
+                Layout.fillWidth: true
+                enabled: !root.segmenting && root.currentFile !== ""
+                onClicked: {
+                    root.threshold = thresholdSpin.value;
+                    root.segmenting = true;
+                    streamController.splitData(root.currentFile, root.threshold);
+                }
+
+                background: Rectangle {
+                    radius: Theme.radiusSm
+                    color: splitBtn.enabled ? Theme.primaryAccent : Theme.buttonNeutralBackground
+                    border.color: splitBtn.enabled ? Theme.primaryAccent : "transparent"
+                    border.width: 1
+                }
+                contentItem: Row {
+                    spacing: 8
+                    anchors.centerIn: parent
+
+                    Label {
+                        text: splitBtn.enabled ? (root.segmenting ? "Segmenting..." : "SPLIT") : "LOAD DATA FIRST"
+                        color: splitBtn.enabled ? Theme.tone100 : Theme.sideMutedText
+                        font.pixelSize: Theme.fontSm
+                        font.bold: true
+                        font.letterSpacing: 1.0
+                    }
+
+                    BusyIndicator {
+                        running: root.segmenting
+                        visible: root.segmenting
+                        width: 16
+                        height: 16
+                    }
+                }
+            }
+        }
+
+        // ── Segments Table ────────────────────────────────────────
+        Rectangle {
+            Layout.fillWidth: true
+            Layout.fillHeight: true
+            radius: Theme.radiusSm
+            color: Theme.panelBackground
+            border.color: Theme.cardBorder
+            border.width: 1
+
+            ColumnLayout {
+                anchors.fill: parent
+                anchors.margins: 0
+                spacing: 0
+
+                // Table header
+                Rectangle {
+                    Layout.fillWidth: true
+                    Layout.preferredHeight: 36
+                    color: Theme.subtleSectionBackground
+                    border.color: Theme.cardBorder
+                    border.width: 1
+
+                    RowLayout {
+                        anchors.fill: parent
+                        anchors.margins: 12
+                        spacing: 8
+
+                        Label { text: "PHASE"; Layout.preferredWidth: 100; color: Theme.sideMutedText; font.bold: true; font.pixelSize: Theme.fontSm }
+                        Label { text: "START (s)"; Layout.preferredWidth: 120; color: Theme.sideMutedText; font.bold: true; font.pixelSize: Theme.fontSm }
+                        Label { text: "END (s)"; Layout.preferredWidth: 120; color: Theme.sideMutedText; font.bold: true; font.pixelSize: Theme.fontSm }
+                        Label { text: "AVG TEMP (°C)"; Layout.fillWidth: true; color: Theme.sideMutedText; font.bold: true; font.pixelSize: Theme.fontSm }
+                        Item { Layout.preferredWidth: 80 }
+                    }
+                }
+
+                // Table body (scrollable)
+                ScrollView {
+                    Layout.fillWidth: true
+                    Layout.fillHeight: true
+                    clip: true
+
+                    ColumnLayout {
+                        width: parent.width - 32
+                        spacing: 0
+
+                        Repeater {
+                            model: root.segments.length > 0 ? root.segments : []
+                            delegate: Rectangle {
+                                Layout.fillWidth: true
+                                Layout.preferredHeight: 40
+                                color: index % 2 === 0 ? Theme.cardBackground : "transparent"
+                                border.color: Theme.cardBorder
+
+                                RowLayout {
+                                    anchors.fill: parent
+                                    anchors.margins: 12
+                                    spacing: 8
+
+                                    Label {
+                                        text: modelData.label || ""
+                                        Layout.preferredWidth: 100
+                                        color: modelData.label === "Soak" ? Theme.statusSuccessColor :
+                                               modelData.label === "Ramp" ? Theme.statusWarningColor : Theme.bodyColor
+                                        font.bold: true
+                                        font.pixelSize: Theme.fontSm
+                                    }
+
+                                    Label {
+                                        text: (modelData.start_frame || 0).toString()
+                                        Layout.preferredWidth: 120
+                                        color: Theme.bodyColor
+                                        font.pixelSize: Theme.fontSm
+                                    }
+
+                                    Label {
+                                        text: (modelData.end_frame || 0).toString()
+                                        Layout.preferredWidth: 120
+                                        color: Theme.bodyColor
+                                        font.pixelSize: Theme.fontSm
+                                    }
+
+                                    Label {
+                                        text: (modelData.avg_temp || 0).toFixed(2) + " °C"
+                                        Layout.fillWidth: true
+                                        color: Theme.bodyColor
+                                        font.pixelSize: Theme.fontSm
+                                    }
+
+                                    Button {
+                                        id: exportBtn
+                                        text: "Export"
+                                        Layout.preferredWidth: 80
+                                        Layout.preferredHeight: 26
+                                        hoverEnabled: true
+                                        onClicked: streamController.exportSegment(index)
+
+                                        background: Rectangle {
+                                            radius: Theme.radiusXs
+                                            color: exportBtn.pressed ? Theme.buttonNeutralPressed
+                                                 : exportBtn.hovered ? Theme.buttonNeutralHover
+                                                 : Theme.buttonNeutralBackground
+                                            border.color: Theme.fieldBorder
+                                            border.width: 1
+                                        }
+                                        contentItem: Label {
+                                            text: exportBtn.text
+                                            color: Theme.buttonNeutralText
+                                            font.pixelSize: Theme.fontXs
+                                            horizontalAlignment: Text.AlignHCenter
+                                            verticalAlignment: Text.AlignVCenter
+                                        }
+                                    }
+                                }
+                            }
+                        }
+
+                        // Empty state
+                        Label {
+                            visible: root.segments.length === 0
+                            text: root.currentFile !== "" ? "Click SPLIT to segment data" : "Load a CSV file first"
+                            color: Theme.sideMutedText
+                            font.pixelSize: Theme.fontSm
+                            Layout.fillWidth: true
+                            Layout.preferredHeight: 100
+                            horizontalAlignment: Text.AlignHCenter
+                            verticalAlignment: Text.AlignVCenter
+                        }
+                    }
+                }
+            }
+        }
+
+        // ── Summary line ──────────────────────────────────────────
+        Label {
+            visible: root.segments.length > 0
+            text: root.segments.length + " segment" + (root.segments.length === 1 ? "" : "s")
+                + " found above " + root.threshold.toFixed(0) + "°C threshold."
+            color: Theme.bodyColor
+            font.pixelSize: Theme.fontSm
+        }
+
+        // ── Export feedback ───────────────────────────────────────
+        Label {
+            id: exportStatus
+            visible: text !== ""
+            color: Theme.bodyColor
+            font.pixelSize: Theme.fontSm
+            elide: Text.ElideMiddle
+            Layout.fillWidth: true
+        }
+    }
+
+    // ── Backend Connection ────────────────────────────────────────
+    Connections {
+        target: streamController
+        function onSplitResult(result) {
+            root.segmenting = false;
+            exportStatus.text = "";
+            if (result && result.success) {
+                root.segments = result.segments || [];
+                console.log("[SplitDialog] Segmented into", root.segments.length, "phases");
+            } else {
+                root.segments = [];
+                console.log("[SplitDialog] Split failed:", result.error || "unknown");
+            }
+        }
+
+        function onSegmentExported(result) {
+            if (result && result.success)
+                exportStatus.text = "Exported: " + result.path.split("/").pop();
+            else
+                exportStatus.text = "Export failed: " + (result.error || "unknown");
+        }
+    }
+
+}

src/pygui/ISC/Tabs/components/StatusActionsPanel.qml

@@ -0,0 +1,115 @@
+import QtQuick
+import QtQuick.Controls
+import QtQuick.Controls.impl
+import QtQuick.Layouts
+import ISC
+import ISC.Tabs.components
+
+// ── Status tab: Hardware Actions + Log Actions ──────────
+ColumnLayout {
+    spacing: Theme.sideRailSpacing
+
+    Rectangle {
+        Layout.fillWidth: true
+        Layout.preferredHeight: hwActionsCol.implicitHeight + 28
+        radius: Theme.sidePanelRadius
+        border.color: Theme.sideBorder
+        border.width: 1
+        color: Theme.sidePanelBackground
+
+        ColumnLayout {
+            id: hwActionsCol
+            anchors.fill: parent
+            anchors.margins: 14
+            spacing: 6
+
+            Label {
+                text: "HARDWARE ACTIONS"
+                color: Theme.sideMutedText
+                font.family: Theme.uiFontFamily
+                font.pixelSize: Theme.fontSm
+                font.letterSpacing: 1.5
+                font.bold: true
+            }
+
+            RailActionButton {
+                label: "DETECT WAFER"
+                iconSource: "../icons/detect.svg"
+                Layout.fillWidth: true
+                enabled: !deviceController.operationInProgress
+                onClicked: root._doDetect()
+            }
+
+            RailActionButton {
+                label: "READ MEMORY"
+                iconSource: "../icons/read.svg"
+                Layout.fillWidth: true
+                enabled: deviceController.waferDetected && !deviceController.operationInProgress
+                onClicked: deviceController.readMemoryAsync()
+            }
+
+            RailActionButton {
+                label: "ERASE MEMORY"
+                iconSource: "../icons/erase.svg"
+                Layout.fillWidth: true
+                destructive: true
+                enabled: deviceController.waferDetected && !deviceController.operationInProgress
+                onClicked: deviceController.eraseMemory(
+                    deviceController.selectedPort)
+            }
+
+            RailActionButton {
+                label: "READ DEBUG"
+                iconSource: "../icons/read.svg"
+                Layout.fillWidth: true
+                // One-shot toggle: "on" while the debug read is in flight,
+                // resets automatically once deviceController flips status.
+                toggled: deviceController.connectionStatus === "Reading debug..."
+                enabled: deviceController.waferDetected && !deviceController.operationInProgress
+                onClicked: deviceController.readDebug(deviceController.selectedPort)
+            }
+        }
+    }
+
+    Rectangle {
+        Layout.fillWidth: true
+        Layout.preferredHeight: logActionsCol.implicitHeight + 28
+        radius: Theme.sidePanelRadius
+        border.color: Theme.sideBorder
+        border.width: 1
+        color: Theme.sidePanelBackground
+
+        ColumnLayout {
+            id: logActionsCol
+            anchors.fill: parent
+            anchors.margins: 14
+            spacing: 6
+
+            Label {
+                text: "LOG ACTIONS"
+                color: Theme.sideMutedText
+                font.family: Theme.uiFontFamily
+                font.pixelSize: Theme.fontSm
+                font.letterSpacing: 1.5
+                font.bold: true
+            }
+
+            RailActionButton {
+                label: "REFRESH SESSION"
+                iconSource: "../icons/refresh.svg"
+                Layout.fillWidth: true
+                enabled: !deviceController.operationInProgress
+                onClicked: deviceController.clearSession()
+            }
+
+            RailActionButton {
+                label: "CLEAR LOG"
+                iconSource: "../icons/x.svg"
+                Layout.fillWidth: true
+                onClicked: deviceController.clearActivityLog()
+            }
+        }
+    }
+
+    Item { Layout.fillHeight: true }
+}

src/pygui/ISC/Tabs/components/StreamControlPanel.qml

@@ -0,0 +1,374 @@
+import QtQuick
+import QtQuick.Controls
+import QtQuick.Controls.impl
+import QtQuick.Dialogs
+import QtQuick.Layouts
+import ISC
+
+Rectangle {
+    id: root
+    Layout.fillWidth: true
+    implicitHeight: contentCol.implicitHeight + 24
+
+    color: Theme.sidePanelBackground
+    radius: Theme.sidePanelRadius
+    border.color: Theme.sideBorder
+    border.width: 1
+
+    signal exportRequested(string filePath, string extra)
+
+    property int _liveSecs: 0
+    Connections {
+        target: streamController
+        function onModeChanged() {
+            if (streamController.mode === "review" && modeBar.currentIndex !== 0) {
+                modeBar.currentIndex = 0;
+            }
+        }
+    }
+    Timer {
+        id: liveTimer
+        interval: 1000
+        repeat: true
+        running: streamController.mode === "live" && streamController.state !== "idle"
+        onTriggered: root._liveSecs++
+        onRunningChanged: if (!running) root._liveSecs = 0
+    }
+
+    function fmtTime(s) {
+        var m = Math.floor(s / 60);
+        var ss = s % 60;
+        return (m < 10 ? "0" : "") + m + ":" + (ss < 10 ? "0" : "") + ss;
+    }
+
+    function switchToReview() {
+        modeBar.currentIndex = 0;
+    }
+
+    ColumnLayout {
+        id: contentCol
+        anchors {
+            fill: parent
+            topMargin: 10
+            leftMargin: 12
+            rightMargin: 12
+            bottomMargin: 12
+        }
+        spacing: 8
+
+        RowLayout {
+            Layout.fillWidth: true
+            spacing: 6
+
+            TabBar {
+                id: modeBar
+                currentIndex: 0
+                spacing: 2
+                padding: 2
+                Layout.fillWidth: true
+                Layout.preferredHeight: 28
+                background: Rectangle {
+                    color: Theme.subtleSectionBackground
+                    radius: Theme.radiusXs
+                    border.color: Theme.cardBorder
+                    border.width: 1
+                }
+
+                TabButton {
+                    text: "Review"
+                    Layout.fillWidth: true
+                    implicitHeight: 24
+                    font.pixelSize: Theme.fontMd
+                    font.weight: parent.checked ? Font.Medium : Font.Normal
+                    background: Rectangle {
+                        color: parent.checked ? Theme.tabActiveBackground : "transparent"
+                        radius: Theme.radiusXs - 1
+                    }
+                    contentItem: Text {
+                        text: parent.text
+                        color: parent.checked ? Theme.headingColor : Theme.bodyColor
+                        font: parent.font
+                        horizontalAlignment: Text.AlignHCenter
+                        verticalAlignment: Text.AlignVCenter
+                    }
+                }
+
+                TabButton {
+                    id: liveTab
+                    text: "Live"
+                    enabled: deviceController.connectionStatus === "Connected"
+                    opacity: enabled ? 1.0 : 0.4
+                    Layout.fillWidth: true
+                    implicitHeight: 24
+                    font.pixelSize: Theme.fontMd
+                    font.weight: parent.checked ? Font.Medium : Font.Normal
+
+                    AppToolTip {
+                        visible: disabledHover.containsMouse && !liveTab.enabled
+                        text: "Connect a wafer to enable Live mode"
+                        delay: 300
+                    }
+
+                    MouseArea {
+                        id: disabledHover
+                        anchors.fill: parent
+                        enabled: !liveTab.enabled
+                        hoverEnabled: true
+                        acceptedButtons: Qt.NoButton
+                    }
+
+                    background: Rectangle {
+                        color: parent.checked ? Theme.tabActiveBackground : "transparent"
+                        radius: Theme.radiusXs - 1
+                    }
+
+                    contentItem: Item {
+                        Row {
+                            spacing: 4
+                            anchors.centerIn: parent
+                            Rectangle {
+                                id: liveTabDot
+                                width: 5; height: 5; radius: 2.5
+                                anchors.verticalCenter: parent.verticalCenter
+                                color: liveTab.enabled ? Theme.metricGood : Theme.sideMutedText
+
+                                SequentialAnimation on opacity {
+                                    running: streamController.mode === "live" && streamController.state !== "idle"
+                                    loops: Animation.Infinite
+                                    NumberAnimation { to: 0.2; duration: 600; easing.type: Easing.InOutQuad }
+                                    NumberAnimation { to: 1.0; duration: 600; easing.type: Easing.InOutQuad }
+                                    onRunningChanged: if (!running) liveTabDot.opacity = 1.0
+                                }
+                            }
+                            Text {
+                                text: liveTab.text
+                                color: liveTab.checked ? Theme.headingColor : Theme.bodyColor
+                                font: liveTab.font
+                                verticalAlignment: Text.AlignVCenter
+                                height: parent.height
+                            }
+                    }
+                }
+            }
+
+            onCurrentIndexChanged: {
+                    if (currentIndex === 1) {
+                        if (deviceController.connectionStatus !== "Connected") {
+                            currentIndex = 0;
+                            return;
+                        }
+                        streamController.setMode("live");
+                        var fc = "";
+                        if (deviceController.lastWaferInfo && deviceController.lastWaferInfo.length > 0) {
+                            fc = deviceController.lastWaferInfo[0];
+                        }
+                        streamController.startStream(deviceController.selectedPort, fc);
+                    } else {
+                        streamController.setMode("review");
+                    }
+                }
+            }
+        }
+
+        Rectangle {
+            Layout.fillWidth: true
+            height: 1
+            color: Theme.cardBorder
+        }
+
+        Label {
+            text: "METRICS"
+            color: Theme.sideMutedText
+            font.family: Theme.uiFontFamily
+            font.pixelSize: Theme.fontMd
+            font.letterSpacing: 1.5
+            font.bold: true
+            Layout.bottomMargin: 2
+        }
+
+        MetricRow {
+            label: "Received Frames"
+            value: modeBar.currentIndex === 1 ? streamController.receivedCount : "—"
+        }
+
+        MetricRow {
+            label: "Errors"
+            value: modeBar.currentIndex === 1 ? streamController.errorCount : "—"
+            valueColor: streamController.errorCount > 0 ? Theme.statusWarningColor : Theme.headingColor
+        }
+
+        MetricRow {
+            label: "Resyncs"
+            value: modeBar.currentIndex === 1 ? streamController.resyncCount : "—"
+        }
+
+        MetricRow {
+            label: "Elapsed"
+            value: modeBar.currentIndex === 1 ? root.fmtTime(root._liveSecs) : "—"
+        }
+
+        Rectangle {
+            Layout.fillWidth: true
+            height: 1
+            color: Theme.cardBorder
+        }
+
+        Label {
+            text: "ACTIONS"
+            color: Theme.sideMutedText
+            font.family: Theme.uiFontFamily
+            font.pixelSize: Theme.fontMd
+            font.letterSpacing: 1.5
+            font.bold: true
+            Layout.bottomMargin: 2
+        }
+
+        RowLayout {
+            Layout.fillWidth: true
+            spacing: 6
+
+            Button {
+                id: recordBtn
+                Layout.fillWidth: true
+                implicitHeight: 28
+                enabled: streamController.mode === "live"
+                opacity: enabled ? 1.0 : 0.4
+                text: streamController.recording ? "Stop REC" : "Record"
+
+                AppToolTip {
+                    visible: recordBtn.hovered && !recordBtn.enabled
+                    text: "Connect to Live to start recording"
+                    delay: 300
+                }
+
+                onClicked: {
+                    if (streamController.recording) {
+                        streamController.stopRecording();
+                    } else {
+                        var info = deviceController.lastWaferInfo;
+                        var serial = (info && info.length > 1) ? info[1] : "";
+                        var ts = Qt.formatDateTime(new Date(), "yyyyMMdd_HHmmss");
+                        var name = "live_" + (serial ? serial + "_" : "") + ts + ".csv";
+                        streamController.startRecording(deviceController.saveDataDir + "/" + name, serial);
+                    }
+                }
+
+                background: Rectangle {
+                    radius: Theme.radiusSm
+                    color: recordBtn.down ? Theme.transportButtonHover
+                         : (recordBtn.hovered ? Theme.transportButtonBg : "transparent")
+                    border.width: Theme.borderThin
+                    border.color: Theme.sideBorder
+                }
+                contentItem: Text {
+                    text: recordBtn.text
+                    color: Theme.headingColor
+                    font.pixelSize: Theme.fontMd
+                    font.weight: Font.Medium
+                    horizontalAlignment: Text.AlignHCenter
+                    verticalAlignment: Text.AlignVCenter
+                }
+            }
+
+            Button {
+                id: exportBtn
+                Layout.fillWidth: true
+                implicitHeight: 28
+                text: "Export"
+                // Nothing to export until a file is loaded or a stream has played
+                enabled: streamController.sensorValues.length > 0
+                opacity: enabled ? 1 : 0.4
+
+                onClicked: {
+                    // Default into <saveDataDir>/Export (created on demand)
+                    exportDialog.selectedFile = "file://" + deviceController.exportDir() + "/wafer_map.png"
+                    exportDialog.open()
+                }
+
+                background: Rectangle {
+                    radius: Theme.radiusSm
+                    color: exportBtn.down ? Theme.transportButtonHover
+                         : (exportBtn.hovered ? Theme.transportButtonBg : "transparent")
+                    border.width: Theme.borderThin
+                    border.color: Theme.sideBorder
+                }
+                contentItem: Text {
+                    text: exportBtn.text
+                    color: Theme.headingColor
+                    font.pixelSize: Theme.fontMd
+                    font.weight: Font.Medium
+                    horizontalAlignment: Text.AlignHCenter
+                    verticalAlignment: Text.AlignVCenter
+                }
+            }
+
+            FileDialog {
+                id: exportDialog
+                title: "Export Wafer Map"
+                fileMode: FileDialog.SaveFile
+                defaultSuffix: "png"
+                nameFilters: ["PNG files (*.png)"]
+                onAccepted: {
+                    var path = String(selectedFile).replace(/^file:\/\//, "");
+                    var extra = "";
+                    if (streamController.mode === "live") {
+                        extra = "Frames: " + streamController.receivedCount
+                              + "   Errors: " + streamController.errorCount
+                              + "   Resyncs: " + streamController.resyncCount
+                              + "   Elapsed: " + root.fmtTime(root._liveSecs);
+                    }
+                    root.exportRequested(path, extra);
+                }
+            }
+        }
+
+        Rectangle {
+            Layout.fillWidth: true
+            height: 1
+            color: Theme.cardBorder
+        }
+
+        Button {
+            id: primaryBtn
+            Layout.fillWidth: true
+            implicitHeight: 32
+            text: streamController.mode === "live" ? "STOP" : "START"
+            enabled: streamController.mode === "live"
+                     ? true
+                     : deviceController.connectionStatus === "Connected"
+            opacity: enabled ? 1.0 : 0.4
+
+            AppToolTip {
+                visible: primaryBtn.hovered && !primaryBtn.enabled
+                text: "Connect a wafer to enable Live mode"
+                delay: 300
+            }
+
+            onClicked: {
+                if (streamController.mode === "live") {
+                    streamController.stopStream();
+                    modeBar.currentIndex = 0;
+                } else {
+                    modeBar.currentIndex = 1;
+                }
+            }
+
+            background: Rectangle {
+                radius: Theme.radiusSm
+                color: primaryBtn.down ? Theme.transportButtonHover
+                     : (primaryBtn.hovered ? Theme.transportButtonBg : "transparent")
+                border.width: Theme.borderThin
+                border.color: Theme.sideBorder
+            }
+            contentItem: Text {
+                text: primaryBtn.text
+                color: Theme.headingColor
+                font.pixelSize: Theme.fontMd
+                font.weight: Font.Medium
+                font.letterSpacing: 1.0
+                horizontalAlignment: Text.AlignHCenter
+                verticalAlignment: Text.AlignVCenter
+            }
+        }
+    }
+}

src/pygui/ISC/Tabs/components/TransportBar.qml

@@ -1,11 +1,14 @@
 import QtQuick
 import QtQuick.Controls
+import QtQuick.Controls.impl
 import QtQuick.Layouts
 import ISC
 
 // ===== Control Bar =====
-// Mode-aware footer: cross-fades between Live and Review layouts.
-// Both variants render as a single centered pill — no full-width bar.
+// Review-mode transport footer (frame counter, play/pause/step, speed).
+// Live-mode's Received/Errors/Stop moved to ReadoutPanel's "LIVE STREAM"
+// card so this bar can collapse to zero height and free vertical space for
+// the trend chart while streaming.
 Item {
     id: bar
     Layout.fillWidth: true
@@ -15,120 +18,13 @@ Item {
     }
     clip: true
 
-    // Hide entirely when in review mode with no file loaded
-    readonly property bool hasContent: {
-        if (streamController.mode === "live") return true;
-        return streamController.loadedFile !== "";
-    }
-    readonly property bool isLive: streamController.mode === "live"
-
-    // ── LIVE MODE ─────────────────────────────────────────────────
-    Item {
-        id: liveContent
-        anchors.fill: parent
-        opacity: bar.isLive ? 1.0 : 0.0
-        visible: opacity > 0
-        Behavior on opacity {
-            NumberAnimation { duration: Theme.durationBase; easing.type: Theme.easeStandard }
-        }
-
-        // Single centered pill for Received + Errors + Stop
-        Rectangle {
-            anchors.centerIn: parent
-            implicitWidth: liveRow.implicitWidth + 48
-            implicitHeight: 68
-            radius: Theme.radiusMd
-            color: Theme.sidePanelBackground
-            border.color: Theme.sideBorder
-            border.width: 1
-
-            Row {
-                id: liveRow
-                anchors.centerIn: parent
-                spacing: 24
-
-                // Received counter
-                Text {
-                    anchors.verticalCenter: parent.verticalCenter
-                    text: "Received: " + streamController.receivedCount
-                    color: Theme.sideMutedText
-                    font.family: Theme.uiFontFamily
-                    font.pixelSize: Theme.fontMd
-                    font.weight: Font.Medium
-                }
-
-                // Separator
-                Rectangle {
-                    anchors.verticalCenter: parent.verticalCenter
-                    width: 1
-                    height: 36
-                    color: Theme.sideBorder
-                }
-
-                // Errors counter
-                Text {
-                    anchors.verticalCenter: parent.verticalCenter
-                    text: "Errors: " + streamController.errorCount
-                    color: streamController.errorCount > 0
-                        ? Theme.statusWarningColor : Theme.sideMutedText
-                    font.family: Theme.uiFontFamily
-                    font.pixelSize: Theme.fontMd
-                    font.weight: Font.Medium
-                }
-
-                // Separator
-                Rectangle {
-                    anchors.verticalCenter: parent.verticalCenter
-                    width: 1
-                    height: 36
-                    color: Theme.sideBorder
-                }
-
-                // STOP button
-                Button {
-                    id: stopBtn
-                    anchors.verticalCenter: parent.verticalCenter
-                    implicitWidth: 112
-                    implicitHeight: 48
-                    hoverEnabled: true
-                    text: "STOP"
-                    font.family: Theme.uiFontFamily
-                    font.pixelSize: Theme.fontSm
-                    font.weight: Font.Medium
-                    font.letterSpacing: 1.0
-
-                    background: Rectangle {
-                        radius: 8
-                        color: stopBtn.pressed ? Theme.transportButtonHover
-                             : Theme.transportButtonBg
-                        border.color: Theme.sideBorder
-                        border.width: 1
-                        Behavior on color {
-                            ColorAnimation { duration: Theme.durationFast }
-                        }
-                    }
-                    contentItem: Text {
-                        text: parent.text
-                        color: Theme.headingColor
-                        font: parent.font
-                        horizontalAlignment: Text.AlignHCenter
-                        verticalAlignment: Text.AlignVCenter
-                    }
-                    onClicked: streamController.stopStream()
-                }
-            }
-        }
-    }
+    // Only shown in review mode, and only once a file is loaded
+    readonly property bool hasContent: streamController.mode !== "live" && streamController.loadedFile !== ""
 
     // ── REVIEW MODE ──────────────────────────────────────────────
     Item {
         id: reviewContent
         anchors.fill: parent
-        opacity: !bar.isLive ? 1.0 : 0.0
-        visible: opacity > 0
-        Behavior on opacity {
-            NumberAnimation { duration: Theme.durationBase; easing.type: Theme.easeStandard }
-        }
 
         // Single centered pill for frame counter + transport + speed
         Rectangle {
@@ -146,15 +42,69 @@ Item {
                 spacing: 24
 
                 // Frame counter
-                Text {
+                Row {
+                    spacing: 6
                     anchors.verticalCenter: parent.verticalCenter
-                    text: "Frame " + (streamController.frameIndex + 1)
-                        + " / " + streamController.frameTotal
-                    color: Theme.sideMutedText
-                    font.family: Theme.uiFontFamily
-                    font.pixelSize: Theme.fontMd
-                    font.weight: Font.Medium
-                    leftPadding: 8
+
+                    Label {
+                        text: "Frame"
+                        color: Theme.sideMutedText
+                        font.family: Theme.uiFontFamily
+                        font.pixelSize: Theme.fontMd
+                        font.weight: Font.Medium
+                        anchors.verticalCenter: parent.verticalCenter
+                    }
+
+                    TextField {
+                        id: frameInput
+                        text: String(streamController.frameIndex + 1)
+                        font.pixelSize: Theme.fontMd
+                        font.weight: Font.Medium
+                        font.family: Theme.codeFontFamily
+                        color: Theme.headingColor
+                        verticalAlignment: TextInput.AlignVCenter
+                        horizontalAlignment: TextInput.AlignHCenter
+                        selectByMouse: true
+                        inputMethodHints: Qt.ImhDigitsOnly
+                        padding: 0
+                        width: Math.max(44, contentWidth + 16)
+                        height: 28
+                        anchors.verticalCenter: parent.verticalCenter
+
+                        background: Rectangle {
+                            color: Theme.fieldBackground
+                            radius: Theme.radiusXs
+                            border.color: frameInput.activeFocus ? Theme.fieldBorderFocus : (frameInput.hovered ? Theme.fieldBorderFocus : Theme.sideBorder)
+                            border.width: 1
+                        }
+
+                        onEditingFinished: {
+                            var val = parseInt(text)
+                            if (!isNaN(val)) {
+                                var targetFrame = Math.max(1, Math.min(val, streamController.frameTotal))
+                                streamController.seek(targetFrame - 1)
+                            }
+                            text = String(streamController.frameIndex + 1)
+                        }
+
+                        Connections {
+                            target: streamController
+                            function onFrameUpdated() {
+                                if (!frameInput.activeFocus) {
+                                    frameInput.text = String(streamController.frameIndex + 1)
+                                }
+                            }
+                        }
+                    }
+
+                    Label {
+                        text: "/ " + streamController.frameTotal
+                        color: Theme.sideMutedText
+                        font.family: Theme.uiFontFamily
+                        font.pixelSize: Theme.fontMd
+                        font.weight: Font.Medium
+                        anchors.verticalCenter: parent.verticalCenter
+                    }
                 }
 
                 // Separator 1
@@ -177,8 +127,6 @@ Item {
                         implicitWidth: 56
                         implicitHeight: 56
                         hoverEnabled: true
-                        text: "⏮"
-                        font.pixelSize: 24
                         background: Rectangle {
                             radius: 8
                             color: skipStartBtn.pressed ? Theme.transportButtonHover
@@ -188,12 +136,13 @@ Item {
                                 ColorAnimation { duration: Theme.durationFast }
                             }
                         }
-                        contentItem: Text {
-                            text: parent.text
+                        contentItem: IconImage {
+                            source: "../icons/prev.svg"
+                            width: 22; height: 22
+                            sourceSize.width: 22
+                            sourceSize.height: 22
                             color: Theme.headingColor
-                            font: parent.font
-                            horizontalAlignment: Text.AlignHCenter
-                            verticalAlignment: Text.AlignVCenter
+                            anchors.centerIn: parent
                         }
                         onClicked: streamController.step(-1)
                     }
@@ -205,8 +154,6 @@ Item {
                         implicitWidth: 56
                         implicitHeight: 56
                         hoverEnabled: true
-                        text: "■"
-                        font.pixelSize: 22
                         background: Rectangle {
                             radius: 8
                             color: reviewStopBtn.pressed ? Theme.transportButtonHover
@@ -216,12 +163,13 @@ Item {
                                 ColorAnimation { duration: Theme.durationFast }
                             }
                         }
-                        contentItem: Text {
-                            text: parent.text
+                        contentItem: IconImage {
+                            source: "../icons/stop.svg"
+                            width: 20; height: 20
+                            sourceSize.width: 20
+                            sourceSize.height: 20
                             color: Theme.headingColor
-                            font: parent.font
-                            horizontalAlignment: Text.AlignHCenter
-                            verticalAlignment: Text.AlignVCenter
+                            anchors.centerIn: parent
                         }
                         onClicked: streamController.stop()
                     }
@@ -230,11 +178,9 @@ Item {
                     Button {
                         id: playPauseBtn
                         anchors.verticalCenter: parent.verticalCenter
-                        implicitWidth: 64
+                        implicitWidth: 56
                         implicitHeight: 56
                         hoverEnabled: true
-                        text: streamController.playing ? "⏸" : "▶"
-                        font.pixelSize: 24
                         background: Rectangle {
                             radius: 8
                             color: playPauseBtn.pressed ? Theme.transportButtonHover
@@ -244,13 +190,13 @@ Item {
                                 ColorAnimation { duration: Theme.durationFast }
                             }
                         }
-                        contentItem: Text {
-                            text: parent.text
+                        contentItem: IconImage {
+                            source: streamController.playing ? "../icons/pause.svg" : "../icons/play.svg"
+                            width: 22; height: 22
+                            sourceSize.width: 22
+                            sourceSize.height: 22
                             color: Theme.headingColor
-                            font: parent.font
-                            horizontalAlignment: Text.AlignHCenter
-                            verticalAlignment: Text.AlignVCenter
-                            leftPadding: parent.text === "▶" ? 4 : 0
+                            anchors.centerIn: parent
                         }
                         onClicked: {
                             if (streamController.playing) {
@@ -268,8 +214,6 @@ Item {
                         implicitWidth: 56
                         implicitHeight: 56
                         hoverEnabled: true
-                        text: "⏭"
-                        font.pixelSize: 24
                         background: Rectangle {
                             radius: 8
                             color: skipEndBtn.pressed ? Theme.transportButtonHover
@@ -279,12 +223,13 @@ Item {
                                 ColorAnimation { duration: Theme.durationFast }
                             }
                         }
-                        contentItem: Text {
-                            text: parent.text
+                        contentItem: IconImage {
+                            source: "../icons/next.svg"
+                            width: 22; height: 22
+                            sourceSize.width: 22
+                            sourceSize.height: 22
                             color: Theme.headingColor
-                            font: parent.font
-                            horizontalAlignment: Text.AlignHCenter
-                            verticalAlignment: Text.AlignVCenter
+                            anchors.centerIn: parent
                         }
                         onClicked: streamController.step(1)
                     }

src/pygui/ISC/Tabs/components/UtilityFooter.qml

@@ -0,0 +1,115 @@
+import QtQuick
+import QtQuick.Controls
+import QtQuick.Controls.impl
+import QtQuick.Layouts
+import ISC
+
+// ── BOX 4: Utility Buttons ─────────────────────────────────
+Rectangle {
+    id: utilFooter
+    Layout.fillWidth: true
+    Layout.preferredHeight: Theme.sideFooterUtility
+    radius: Theme.sidePanelRadius
+    border.color: Theme.sideBorder
+    border.width: 1
+    color: Theme.sidePanelBackground
+
+    property var settingsPopup: null
+    property var aboutDialog: null
+
+    RowLayout {
+        anchors.fill: parent
+        anchors.margins: 4
+        spacing: 4
+
+        Button {
+            id: settingsBtn
+            flat: true
+            Layout.fillWidth: true
+            Layout.fillHeight: true
+            icon.source: "../icons/settings.svg"
+            onClicked: if (settingsPopup) settingsPopup.open()
+
+            background: Rectangle {
+                radius: 8
+                color: settingsBtn.hovered
+                    ? Theme.sideActiveBackground : "transparent"
+            }
+
+            contentItem: Row {
+                spacing: 6
+                anchors.centerIn: parent
+
+                IconImage {
+                    anchors.verticalCenter: parent.verticalCenter
+                    width: 16
+                    height: 16
+                    source: "../icons/settings.svg"
+                    sourceSize.width: 16
+                    sourceSize.height: 16
+                    color: Theme.headingColor
+                    opacity: 0.75
+                }
+
+                Label {
+                    anchors.verticalCenter: parent.verticalCenter
+                    text: "SETTINGS"
+                    color: Theme.headingColor
+                    font.family: Theme.uiFontFamily
+                    font.pixelSize: Theme.fontXs
+                    font.bold: true
+                    font.letterSpacing: 1.2
+                    opacity: 0.8
+                }
+            }
+        }
+
+        Rectangle {
+            width: 1
+            height: 24
+            color: Theme.sideBorder
+        }
+
+        Button {
+            id: aboutBtn
+            flat: true
+            Layout.fillWidth: true
+            Layout.fillHeight: true
+            icon.source: "../icons/about.svg"
+            onClicked: if (aboutDialog) aboutDialog.open()
+
+            background: Rectangle {
+                radius: 8
+                color: aboutBtn.hovered
+                    ? Theme.sideActiveBackground : "transparent"
+            }
+
+            contentItem: Row {
+                spacing: 6
+                anchors.centerIn: parent
+
+                IconImage {
+                    anchors.verticalCenter: parent.verticalCenter
+                    width: 16
+                    height: 16
+                    source: "../icons/about.svg"
+                    sourceSize.width: 16
+                    sourceSize.height: 16
+                    color: Theme.headingColor
+                    opacity: 0.75
+                }
+
+                Label {
+                    anchors.verticalCenter: parent.verticalCenter
+                    text: "ABOUT"
+                    color: Theme.headingColor
+                    font.family: Theme.uiFontFamily
+                    font.pixelSize: Theme.fontXs
+                    font.bold: true
+                    font.letterSpacing: 1.2
+                    opacity: 0.8
+                }
+            }
+        }
+    }
+}

src/pygui/ISC/Tabs/components/WaferMapView.qml

@@ -7,7 +7,9 @@ Item {
     id: root
     property real blend: 0.0
     property bool showLabels: true
+    property alias showExtremes: map.showExtremes
     property alias showThickness: map.showThickness
+    property alias hasThickness: map.hasThickness
 
     WaferMapItem {
         id: map
@@ -29,8 +31,28 @@ Item {
         highColor: Theme.sensorHigh
         textColor: Theme.headingColor
 
+        // Grows the hovered marker smoothly; hoverScale setter triggers a repaint.
+        hoverScale: 1.0 + 0.35 * hoverPulse
+        property real hoverPulse: map.hoveredIndex >= 0 ? 1.0 : 0.0
+        Behavior on hoverPulse {
+            NumberAnimation { duration: 150; easing.type: Easing.OutQuad }
+        }
+
+        HoverHandler {
+            id: hoverHandler
+            onPointChanged: {
+                map.hoveredIndex = streamController.mode === "live"
+                    ? -1
+                    : map.which_marker(hoverHandler.point.position.x, hoverHandler.point.position.y);
+            }
+            onHoveredChanged: if (!hoverHandler.hovered) map.hoveredIndex = -1
+            cursorShape: map.hoveredIndex >= 0 ? Qt.PointingHandCursor : Qt.ArrowCursor
+        }
+
         TapHandler {
             onTapped: ev => {
+                if (streamController.mode === "live")
+                    return;
                 var idx = map.which_marker(ev.position.x, ev.position.y);
                 if (idx >= 0)
                     replaceDialog.openFor(idx);
@@ -42,7 +64,11 @@ Item {
         id: replaceDialog
     }
 
-    function exportImage(filePath) {
-        return map.export_image(filePath);
+    function exportImage(filePath, extra) {
+        return map.export_image(filePath, extra || "");
+    }
+
+    function loadThickness(filePath) {
+        return map.loadThickness(filePath);
     }
 }

src/pygui/ISC/Tabs/components/qmldir

@@ -6,3 +6,21 @@ TransportBar 1.0 TransportBar.qml
 WaferMapView 1.0 WaferMapView.qml
 ReplaceSensorDialog 1.0 ReplaceSensorDialog.qml
 RailActionButton 1.0 RailActionButton.qml
+SelectFileDialog 1.0 SelectFileDialog.qml
+SplitDialog 1.0 SplitDialog.qml
+StreamControlPanel 1.0 StreamControlPanel.qml
+StatusActionsPanel 1.0 StatusActionsPanel.qml
+ConnectionFooter 1.0 ConnectionFooter.qml
+UtilityFooter 1.0 UtilityFooter.qml
+PanelCheckBox 1.0 PanelCheckBox.qml
+ReadoutStat 1.0 ReadoutStat.qml
+MetricRow 1.0 MetricRow.qml
+AppToolTip 1.0 AppToolTip.qml
+SectionTitle 1.0 SectionTitle.qml
+PanelBox 1.0 PanelBox.qml
+PanelSlider 1.0 PanelSlider.qml
+EditableScrubStat 1.0 EditableScrubStat.qml
+ComparisonChartCard 1.0 ComparisonChartCard.qml
+OverlapMapCard 1.0 OverlapMapCard.qml
+ComparisonSidePanel 1.0 ComparisonSidePanel.qml
+RunChart 1.0 RunChart.qml

src/pygui/ISC/Tabs/icons/back.svg

@@ -0,0 +1,14 @@
+<svg
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <path d="m12 19-7-7 7-7" />
+  <path d="M19 12H5" />
+</svg>

src/pygui/ISC/Tabs/icons/bar-chart.svg

@@ -0,0 +1,15 @@
+<svg
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <line x1="18" x2="18" y1="20" y2="10" />
+  <line x1="12" x2="12" y1="20" y2="4" />
+  <line x1="6" x2="6" y1="20" y2="14" />
+</svg>

src/pygui/ISC/Tabs/icons/check.svg

@@ -0,0 +1,13 @@
+<svg
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <path d="M20 6 9 17l-5-5" />
+</svg>

src/pygui/ISC/Tabs/icons/chevron-down.svg

@@ -0,0 +1,13 @@
+<svg
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <path d="m6 9 6 6 6-6" />
+</svg>

src/pygui/ISC/Tabs/icons/file-text.svg

@@ -0,0 +1,17 @@
+<svg
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <path d="M15 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V7Z" />
+  <path d="M14 2v4a2 2 0 0 0 2 2h4" />
+  <path d="M10 9H8" />
+  <path d="M16 13H8" />
+  <path d="M16 17H8" />
+</svg>

src/pygui/ISC/Tabs/icons/folder.svg

@@ -0,0 +1,13 @@
+<svg
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <path d="M20 20a2 2 0 0 0 2-2V8a2 2 0 0 0-2-2h-7.9a2 2 0 0 1-1.69-.9L9.6 3.9A2 2 0 0 0 7.93 3H4a2 2 0 0 0-2 2v13a2 2 0 0 0 2 2Z" />
+</svg>

src/pygui/ISC/Tabs/icons/next.svg

@@ -0,0 +1,13 @@
+<svg
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <path d="m9 18 6-6-6-6" />
+</svg>

src/pygui/ISC/Tabs/icons/pause.svg

@@ -0,0 +1,14 @@
+<svg
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <rect x="14" y="3" width="5" height="18" rx="1" />
+  <rect x="6" y="3" width="5" height="18" rx="1" />
+</svg>

src/pygui/ISC/Tabs/icons/play.svg

@@ -0,0 +1,13 @@
+<svg
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <polygon points="6 3 20 12 6 21 6 3" />
+</svg>

src/pygui/ISC/Tabs/icons/prev.svg

@@ -0,0 +1,13 @@
+<svg
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <path d="m15 18-6-6 6-6" />
+</svg>

src/pygui/ISC/Tabs/icons/rotate-ccw.svg

@@ -0,0 +1,14 @@
+<svg
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <path d="M3 12a9 9 0 1 0 9-9 9.75 9.75 0 0 0-6.74 2.74L3 8" />
+  <path d="M3 3v5h5" />
+</svg>

src/pygui/ISC/Tabs/icons/stop.svg

@@ -0,0 +1,13 @@
+<svg
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <rect width="18" height="18" x="3" y="3" rx="2" />
+</svg>

src/pygui/ISC/Tabs/icons/triangle-alert.svg

@@ -0,0 +1,15 @@
+<svg
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <path d="m21.73 18-8-14a2 2 0 0 0-3.46 0l-8 14A2 2 0 0 0 4 21h16a2 2 0 0 0 1.73-3Z" />
+  <path d="M12 9v4" />
+  <path d="M12 17h.01" />
+</svg>

src/pygui/ISC/Tabs/icons/x.svg

@@ -0,0 +1,14 @@
+<svg
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <path d="M18 6 6 18" />
+  <path d="m6 6 12 12" />
+</svg>

src/pygui/ISC/Tabs/qmldir

@@ -1,9 +1,7 @@
 # ===== ISC Tabs Module =====
 module ISC.Tabs
 
-GraphTab 1.0 GraphTab.qml
 WaferMapTab 1.0 WaferMapTab.qml
 DataTab 1.0 DataTab.qml
 SettingsTab 1.0 SettingsTab.qml
 StatusTab 1.0 StatusTab.qml
-SelectFileDialog 1.0 SelectFileDialog.qml

src/pygui/ISC/Theme.qml

@@ -7,18 +7,23 @@ import QtQuick
 // =============================================================================
 //  Sections:
 //    1.  Mode flag
-//    2.  Typography
+//    2.  Typography              (families, pixel sizes, weights)
 //    3.  Motion
-//    4.  Tone palette          (raw tones; everything else derives from these)
-//    5.  Surfaces              (page / card / panel / workspace backgrounds)
+//    4.  Tone palette            (raw tones; everything else derives from these)
+//    5.  Surfaces                (page / card / panel / workspace backgrounds)
 //    6.  Borders
-//    7.  Text                  (headings, body, panel titles)
-//    8.  Controls              (fields, buttons, checkbox)
-//    9.  Tracks                (pill toggle + scrollbar)
-//   10.  Tabs                  (footer tab bar)
-//   11.  Side rail
-//   12.  Status                (success / warning / error)
-//   13.  Geometry              (radius / border width / spacing / sizing)
+//    7.  Text                    (headings, body, panel titles)
+//    8.  Controls                (fields, buttons, checkbox, toggle)
+//    9.  Interaction overlays    (hover / active washes — mode-aware)
+//   10.  Tracks                  (pill toggle + scrollbar)
+//   11.  Tabs                    (mode toggle pills)
+//   12.  Side rail
+//   13.  Transport / toolbar
+//   14.  Status & badges         (success / warning / error, badge text)
+//   15.  Sensor bands            (wafer map dots)
+//   16.  Wafer family badges     (source list avatars + accent bars)
+//   17.  Comparison & charts     (metric grading, diff accent, canvas grid)
+//   18.  Geometry                (radius / border width / spacing / sizing)
 // =============================================================================
 //  Based on Codex themes:
 //    Dark  (oscurange):  surface #0B0B0F, ink #E6E6E6
@@ -29,7 +34,10 @@ QtObject {
     // ── 1. Mode ──────────────────────────────────────────────────────────────
     property bool isDarkMode: true
 
-    // ── 2. Typography ──────────────────────────────────────────────────────
+    // ── 2. Typography ────────────────────────────────────────────────────────
+    readonly property string uiFontFamily: "Geist, Inter, system-ui, -apple-system, BlinkMacSystemFont, sans-serif"
+    readonly property string codeFontFamily: "\"Geist Mono\", ui-monospace, \"SFMono-Regular\", monospace"
+
     // pixelSize scale — map to closest token, tune globally
     readonly property int font2xs: 9   // tiny metadata
     readonly property int fontXs: 11   // captions, micro labels
@@ -44,25 +52,20 @@ QtObject {
     readonly property int fontWeightMedium: 500
     readonly property int fontWeightBold: 700
 
-    // Legacy shim
-    readonly property int tabFontSize: fontSm
-
-    // ── 3. Motion ──────────────────────────────────────────────────────────
+    // ── 3. Motion ────────────────────────────────────────────────────────────
     readonly property int durationFast: 120   // micro-interactions (focus ring, hover flash)
     readonly property int durationBase: 180   // standard transitions (pill switch, row select)
     readonly property int durationSlow: 260   // larger transitions (panel open/close)
     readonly property var easeStandard: Easing.OutCubic
 
-    // ── 4. Tone palette (Codex theme v1 inspired) ───────────────────────────
-    readonly property string uiFontFamily: "Geist, Inter, system-ui, -apple-system, BlinkMacSystemFont, sans-serif"
-    readonly property string codeFontFamily: "\"Geist Mono\", ui-monospace, \"SFMono-Regular\", monospace"
-
+    // ── 4. Tone palette (Codex theme v1 inspired) ────────────────────────────
     readonly property color themeSurface: isDarkMode ? "#0B0B0F" : "#F9F9F7"
     readonly property color themeInk: isDarkMode ? "#E6E6E6" : "#2D2D2B"
     readonly property color themeAccent: isDarkMode ? "#F9B98C" : "#B87333"
     readonly property color themeSkill: isDarkMode ? "#479FFA" : "#3B82F6"   // blue family both modes
     readonly property color themeAdded: isDarkMode ? "#40C977" : "#00C853"
     readonly property color themeRemoved: isDarkMode ? "#FA423E" : "#FF5F38"
+    readonly property color themeViolet: isDarkMode ? "#A78BFA" : "#8B5CF6"
 
     readonly property color tone100: themeSurface
     readonly property color tone150: isDarkMode ? "#101014" : "#F3F3F1"
@@ -74,7 +77,7 @@ QtObject {
     readonly property color toneMute: isDarkMode ? "#A8A8A1" : "#85857E"
     readonly property color toneBorder: isDarkMode ? "#2D2D34" : "#D2D2CE"
 
-    // ── 3. Surfaces ──────────────────────────────────────────────────────────
+    // ── 5. Surfaces ──────────────────────────────────────────────────────────
     readonly property color pageBackground: tone100
     readonly property color cardBackground: tone150
     readonly property color panelBackground: tone150
@@ -82,7 +85,7 @@ QtObject {
     readonly property color responseBackground: tone150
     readonly property color subtleSectionBackground: tone250
 
-    // ── 4. Borders ───────────────────────────────────────────────────────────
+    // ── 6. Borders ───────────────────────────────────────────────────────────
     readonly property color cardBorder: toneBorder
     readonly property color cardSurfaceBorder: isDarkMode ? "#3A3A42" : "#C7C7C2"
     readonly property color responseBorder: toneBorder
@@ -91,14 +94,14 @@ QtObject {
     readonly property color outerFrameBorder: isDarkMode ? "#3A3A42" : "#C7C7C2"
     readonly property color softBorder: isDarkMode ? "#24242A" : "#E4E4E1"
 
-    // ── 5. Text ──────────────────────────────────────────────────────────────
+    // ── 7. Text ──────────────────────────────────────────────────────────────
     readonly property color headingColor: toneText
     readonly property color bodyColor: toneMute
     readonly property color subheadingColor: toneMute
     readonly property color panelTitleText: toneMute
     readonly property color disabledText: toneMute
 
-    // ── 6. Controls ──────────────────────────────────────────────────────────
+    // ── 8. Controls ──────────────────────────────────────────────────────────
     // Fields
     readonly property color fieldBackground: isDarkMode ? "#101014" : "#FFFFFF"
     readonly property color fieldText: toneText
@@ -114,42 +117,48 @@ QtObject {
     readonly property color primaryAccent: themeAccent
     // Checkbox
     readonly property color checkboxText: toneText
+    // Toggle switch thumb (white knob reads on both track colors)
+    readonly property color toggleThumb: "#FFFFFF"
 
-    // ── 7. Tracks (pill toggle, scrollbar thumb) ─────────────────────────────
+    // ── 9. Interaction overlays ──────────────────────────────────────────────
+    // Mode-aware washes. Never use raw Qt.rgba(1,1,1,x) in views: a white
+    // overlay is invisible on light-mode surfaces.
+    readonly property color listHoverBackground: isDarkMode ? Qt.rgba(1, 1, 1, 0.04) : Qt.rgba(0, 0, 0, 0.03)
+    readonly property color listActiveBackground: isDarkMode ? Qt.rgba(1, 1, 1, 0.06) : Qt.rgba(0, 0, 0, 0.05)
+    readonly property color flatButtonHover: isDarkMode ? Qt.rgba(1, 1, 1, 0.08) : Qt.rgba(0, 0, 0, 0.06)
+    readonly property color cardWash: isDarkMode ? Qt.rgba(1, 1, 1, 0.02) : Qt.rgba(0, 0, 0, 0.02)
+
+    // ── 10. Tracks (pill toggle, scrollbar thumb) ────────────────────────────
     readonly property color trackBackground: isDarkMode ? "#25252B" : "#E2E2DE"
 
-    // ── 8. Tabs (footer tab bar) ─────────────────────────────────────────────
-    readonly property color tabBarBackground: tone200
-    readonly property color tabBackground: "transparent"
+    // ── 11. Tabs (mode toggle pills) ─────────────────────────────────────────
     readonly property color tabActiveBackground: isDarkMode ? "#25252B" : "#FFFFFF"
-    readonly property color tabHoverBackground: tone250
-    readonly property color tabBorder: "transparent"
-    readonly property color tabText: toneMute
-    readonly property color tabActiveText: toneText
 
-    // ── 9. Side rail ─────────────────────────────────────────────────────────
+    // ── 12. Side rail ────────────────────────────────────────────────────────
     readonly property color sideRailBackground: tone150
     readonly property color sidePanelBackground: isDarkMode ? "#151518" : "#F3F3F1"
     readonly property color sideActiveBackground: isDarkMode ? "#25252B" : "#FFFFFF"
     readonly property color sideBorder: toneBorder
     readonly property color sideMutedText: toneMute
-    readonly property color sideAccent: themeAccent
-    readonly property color sideRowHover: tone250
-    readonly property color sideFieldBackground: isDarkMode ? "#101014" : "#FFFFFF"
 
-    // ── 10a. Transport / toolbar surfaces ────────────────────────────────────
-    readonly property color transportBackground: isDarkMode ? "#101014" : "#EFEFED"
+    // ── 13. Transport / toolbar surfaces ─────────────────────────────────────
     readonly property color transportButtonBg: tone250
     readonly property color transportButtonHover: tone300
     readonly property color liveColor: themeAdded
     readonly property color recordColor: themeRemoved
 
-    // ── 10. Status ───────────────────────────────────────────────────────────
+    // ── 14. Status & badges ──────────────────────────────────────────────────
     readonly property color statusSuccessColor: themeAdded
     readonly property color statusWarningColor: isDarkMode ? "#E8A817" : "#B8860B"   // amber/yellow, separate from accent
     readonly property color statusErrorColor: themeRemoved
+    // Text placed ON a filled status pill / saturated chip:
+    readonly property color statusBadgeText: "#111111"   // dark ink on bright status fills, both modes
+    readonly property color textOnColor: "#FFFFFF"       // white text on deep saturated fills (avatars etc.)
+    // Error banner (soft red surface + readable red text)
+    readonly property color errorSurface: Qt.alpha(statusErrorColor, 0.15)
+    readonly property color errorTextSoft: isDarkMode ? "#FCA5A5" : "#B91C1C"
 
-    // -- 10b. Sensor bands (wafer map dots)
+    // ── 15. Sensor bands (wafer map dots) ────────────────────────────────────
     readonly property color sensorInRange: statusSuccessColor
     // ponytail: high-temp shares error red — semantically correct (dangerous value),
     // re-hue if colorblind testing demands a different channel.
@@ -158,7 +167,31 @@ QtObject {
     readonly property color waferRingColor: toneBorder
     readonly property color waferAxisColor: softBorder
 
-    // ── 11. Geometry ─────────────────────────────────────────────────────────
+    // ── 16. Wafer family badges (SourcePanel list) ───────────────────────────
+    // Accent = left bar / outline shade; Fill = avatar circle behind textOnColor.
+    // Family grouping mirrors FileBrowser's waferType first-letter convention.
+    readonly property color familyBlueAccent: "#3B82F6"    // A / E / P
+    readonly property color familyBlueFill: "#1D4ED8"
+    readonly property color familyGreenAccent: "#10B981"   // B / C / D
+    readonly property color familyGreenFill: "#065F46"
+    readonly property color familyVioletAccent: "#8B5CF6"  // Z
+    readonly property color familyVioletFill: "#7C3AED"
+    readonly property color familyNeutralFill: "#374151"   // unknown family
+
+    // ── 17. Comparison & charts ──────────────────────────────────────────────
+    // Metric grading for DTW readout cards (good → caution → bad).
+    // Dark values are pastel (readable on tone150); light values are deepened
+    // so they still pass on near-white cards.
+    readonly property color metricGood: isDarkMode ? "#6EE7B7" : "#059669"
+    readonly property color metricWarn: isDarkMode ? "#FDE047" : "#B45309"
+    readonly property color metricBad: isDarkMode ? "#EF4444" : "#DC2626"
+    // DIFF column accent in ReadoutPanel
+    readonly property color diffAccent: themeViolet
+    // Canvas chart primitives (DTW plot grid + axis labels)
+    readonly property color chartGridLine: isDarkMode ? Qt.rgba(1, 1, 1, 0.08) : Qt.rgba(0, 0, 0, 0.10)
+    readonly property color chartAxisText: isDarkMode ? Qt.rgba(1, 1, 1, 0.35) : Qt.rgba(0, 0, 0, 0.45)
+
+    // ── 18. Geometry ─────────────────────────────────────────────────────────
     // Radius
     readonly property int radiusXs: 6   // fields, tight elements
     readonly property int radiusSm: 8   // buttons
@@ -172,21 +205,15 @@ QtObject {
     readonly property int rightPaneGap: 6
     readonly property int panelPadding: 12
     // Side rail layout
-    readonly property int sideRailWidth: 280
+    readonly property int sideRailWidth: 300
+    readonly property int rightRailWidth: 280
     readonly property int sideRailMargin: 16
     readonly property int sideRailSpacing: 16
     readonly property int sideButtonHeight: 44
     readonly property int sidePanelRadius: 10
     readonly property int sideFooterConnection: 100
     readonly property int sideFooterUtility: 46
-    // Tab bar layout
-    readonly property int tabBarHeight: 34
     readonly property int sidePillHeight: 54
-    readonly property int sidePillButtonHeight: 36
-    readonly property int tabBarPadding: 6
-    readonly property int tabSpacing: 2
-    readonly property int tabRadius: 8
-    readonly property int tabButtonMinWidth: 80
     // Settings page layout
     readonly property int settingsPanelMaxWidth: 760
     readonly property int settingsOuterMargin: 40

src/pygui/__main__.py

@@ -1,5 +1,6 @@
 import logging
 import sys
+from importlib.metadata import PackageNotFoundError, version
 from pathlib import Path
 
 from PySide6.QtQml import QQmlApplicationEngine
@@ -8,11 +9,22 @@ from PySide6.QtWidgets import QApplication
 
 from pygui.backend.controllers.device_controller import DeviceController
 from pygui.backend.controllers.session_controller import SessionController
+from pygui.backend.data.constants import default_data_dir
 from pygui.backend.data.file_browser import FileBrowser
 from pygui.backend.data.local_settings import LocalSettings
 from pygui.backend.data.local_settings_model import LocalSettingsModel
+from pygui.backend.license.license_model import LicenseModel
 
 # Importing wafer_map_item + trend_chart_item registers @QmlElement types (QML: import ISC.Wafer).
+from pygui.backend.visualization import (
+    graph_quick_item as graph_quick_item,  # noqa: F401
+)
+from pygui.backend.visualization import (
+    trend_chart_item as trend_chart_item,  # noqa: F401
+)
+from pygui.backend.visualization import (
+    wafer_map_item as wafer_map_item,  # noqa: F401
+)
 
 
 # ===== Application Entry Point =====
@@ -30,34 +42,49 @@ def main() -> int:
     app = QApplication(sys.argv)
     engine = QQmlApplicationEngine()
 
-    # ===== Shared Models =====
-    settings_model = LocalSettingsModel()
+    # ===== Shared Settings =====
+    # One LocalSettings instance, one disk read. LocalSettingsModel and
+    # DeviceController both hold this same object, so a save from the
+    # Settings tab is visible to the device layer immediately — no reload,
+    # no second copy to go stale.
+    data_dir = str(default_data_dir())
+    raw_settings = LocalSettings.read_settings(data_dir)
+
+    settings_model = LocalSettingsModel(raw_settings, data_dir)
     select_file_dialog_model = FileBrowser()
     settings_model.loadSettings()
     engine.rootContext().setContextProperty("settingsModel", settings_model)
     engine.rootContext().setContextProperty("file_browser", select_file_dialog_model)
 
+    # App version from package metadata so the About dialog can't drift
+    # from pyproject.toml.
+    try:
+        app_version = version("pygui")
+    except PackageNotFoundError:
+        app_version = "dev"
+    engine.rootContext().setContextProperty("appVersion", app_version)
+
     # ===== Device Controller (serial comm) =====
-    data_dir = str(settings_model._data_dir)
-    raw_settings = LocalSettings.read_settings(data_dir)
+    # TODO P1.1: construct LicenseModel BEFORE DeviceController and pass
+    #   license_lookup=license_model.levelForWafer into the ctor.
+    #   THINKING: controller must answer "is this serial licensed?" at
+    #   read/erase time (P2.1); a bound Callable[[str], str] avoids a
+    #   LicenseModel import in the controller and keeps it testable with a
+    #   lambda. See docs/pending/license-gating-plan.md §1.1.
     device_controller = DeviceController(raw_settings, data_dir)
     engine.rootContext().setContextProperty("deviceController", device_controller)
 
+    # Source panel browses the same folder recordings/reads are saved to.
+    select_file_dialog_model.setCurrentDirectory(str(device_controller.saveDataDir))
+
+    # ===== License Model (About dialog grid, replay trial) =====
+    license_model = LicenseModel(data_dir)
+    engine.rootContext().setContextProperty("licenseModel", license_model)
+
     # ===== Session Controller (live/review wafer dashboard) =====
-    raw_settings_dict = raw_settings.__dict__.copy() if hasattr(raw_settings, '__dict__') else {}
-    stream_controller = SessionController(settings=raw_settings_dict)
+    stream_controller = SessionController()
     engine.rootContext().setContextProperty("streamController", stream_controller)
 
-    # Persist session state back to settings when it changes
-    def _persist_session_settings():
-        session_state = stream_controller.collect_settings()
-        for k, v in session_state.items():
-            if hasattr(raw_settings, k):
-                setattr(raw_settings, k, v)
-        LocalSettings.save_settings(data_dir, raw_settings)
-
-    stream_controller.settingsChanged.connect(_persist_session_settings)
-
     # ===== QML Startup =====
     # The "ISC" QML module lives alongside this file (src/pygui/ISC), so the
     # package directory is the import path the engine searches for qmldir.

src/pygui/backend/__init__.py

@@ -1,26 +0,0 @@
-# ===== Backend Package =====
-# Backward-compatible re-exports so existing callers keep working
-# while imports are migrated to the new sub-package paths.
-
-from pygui.backend.controllers.device_controller import DeviceController  # noqa: F401
-from pygui.backend.controllers.session_controller import SessionController  # noqa: F401
-from pygui.backend.data.csv_file_metadata import CSVFileMetadata  # noqa: F401
-from pygui.backend.data.csv_recorder import CsvRecorder  # noqa: F401
-from pygui.backend.data.data_records import read_data_records  # noqa: F401
-from pygui.backend.data.file_browser import FileBrowser  # noqa: F401
-from pygui.backend.data.local_settings import LocalSettings  # noqa: F401
-from pygui.backend.data.local_settings_model import LocalSettingsModel  # noqa: F401
-from pygui.backend.models.data_model import TemperatureTableModel  # noqa: F401
-from pygui.backend.models.frame import Frame  # noqa: F401
-from pygui.backend.models.frame_player import FramePlayer, frames_from_wafer_data  # noqa: F401
-from pygui.backend.models.frame_stats import Stats, compute_stats  # noqa: F401
-from pygui.backend.models.sensor_editor import SensorEditor  # noqa: F401
-from pygui.backend.models.session_model import SessionModel  # noqa: F401
-from pygui.backend.models.stability_detector import StabilityDetector  # noqa: F401
-from pygui.backend.models.threshold_classifier import ThresholdConfig  # noqa: F401
-from pygui.backend.visualization.graph_view import GraphView  # noqa: F401
-from pygui.backend.visualization.rbf_heatmap import interpolate_field  # noqa: F401
-from pygui.backend.visualization.wafer_map_item import WaferMapItem  # noqa: F401
-from pygui.backend.wafer.wafer_layouts import available_families, load_layout  # noqa: F401
-from pygui.backend.wafer.zwafer_models import DataRecord, Sensor, ZWaferData  # noqa: F401
-from pygui.backend.wafer.zwafer_parser import ZWaferParser  # noqa: F401

src/pygui/backend/controllers/__init__.py

@@ -1,5 +0,0 @@
-# ===== Controllers Sub-package =====
-from pygui.backend.controllers.device_controller import DeviceController
-from pygui.backend.controllers.session_controller import SessionController
-
-__all__ = ["DeviceController", "SessionController"]

src/pygui/backend/controllers/device_controller.py

@@ -3,31 +3,30 @@
 from __future__ import annotations
 
 import logging
+import os
+import subprocess
+import sys
 import threading
 from datetime import datetime
+from pathlib import Path
 from typing import Any, Optional
 
 from PySide6.QtCore import Property, QObject, Qt, Signal, Slot
 
-from pygui.backend.controllers.session_controller import SessionController
 from pygui.backend.data.local_settings import LocalSettings
 from pygui.backend.models.data_model import TemperatureTableModel
 from pygui.backend.utils import slot_error_boundary
 from pygui.backend.visualization.graph_view import GraphView
 from pygui.serialcomm.data_parser import (
+    convert_to_debug_temperatures,
     convert_to_temperatures,
     parse_binary_data,
     remove_trailing_zeros,
+    save_debug_csv,
     save_to_csv,
 )
-from pygui.serialcomm.device_service import DeviceService
 from pygui.serialcomm.serial_port import WaferInfo
 
-# import pygui.backend.wafer_map_item
-
-stream_controller = SessionController()
-# engine.rootContext().setContextProperty("streamController", stream_controller)
-
 log = logging.getLogger(__name__)
 
 
@@ -39,6 +38,10 @@ class DeviceController(QObject):
 
     # ---- public signals ----
     portsUpdated = Signal(list)
+    connectionStatusChanged = Signal()
+    operationInProgressChanged = Signal()
+    waferDetectedChanged = Signal()
+    selectedPortChanged = Signal()
     detectResult = Signal(object)  # WaferInfo dict or None
     readResult = Signal(dict)  # {"success": bool, "bytes": int} or {"error": str}
     eraseResult = Signal(dict)  # {"success": bool}
@@ -51,11 +54,14 @@ class DeviceController(QObject):
     # ---- private signals (marshal worker-thread results back to main thread) ----
     _detectFinished = Signal(object, object)     # (port_or_None, WaferInfo_or_None)
     _readFinished = Signal(str, str, object)     # (port, family_code, bytes_or_None)
+    _eraseFinished = Signal(bool)                # (success)
+    _debugFinished = Signal(dict)                # (result_dict)
 
     def __init__(self, settings: LocalSettings, data_dir: str, parent: QObject | None = None) -> None:
         super().__init__(parent)
         self._settings = settings
         self._data_dir = data_dir
+        from pygui.serialcomm.device_service import DeviceService
         self._service = DeviceService(settings)
 
         # Always start fresh — never restore connection status or logs from a prior session
@@ -63,9 +69,18 @@ class DeviceController(QObject):
         self._operation_in_progress = False
         self._activity_log: list[str] = []
         self._raw_bytes: Optional[bytes] = None
-        from pathlib import Path
         self._save_data_dir: str = getattr(settings, 'save_data_dir', "") or str(Path(self._data_dir) / "csv")
+        # TODO P1.2: accept ctor param license_lookup: Callable[[str], str]
+        #   (default lambda s: "") and add:
+        #     def _wafer_license_level(self) -> str:
+        #         return self._license_lookup(self._last_wafer_info.get("serialNumber", ""))
+        #   plus @Slot(result=bool) waferLicensed() for QML (used by P2.2).
+        #   THINKING: single shared guard — per-call-site checks are the
+        #   sibling-caller bug (fix read, forget erase). Empty serial → ""
+        #   → denied = safe default. Called by P2.1.
+        #   See docs/pending/license-gating-plan.md §1.2.
         self._last_wafer_info: dict[str, Any] = {}
+        self._wafer_detected: bool = False
         self._last_csv_path: str = ""
         self._selected_port: str = ""
         self._data_row_count: int = 0
@@ -79,6 +94,8 @@ class DeviceController(QObject):
         # Marshal worker-thread results onto the Qt main thread.
         self._detectFinished.connect(self._handle_detect_finished, Qt.ConnectionType.QueuedConnection)
         self._readFinished.connect(self._handle_read_finished, Qt.ConnectionType.QueuedConnection)
+        self._eraseFinished.connect(self._handle_erase_finished, Qt.ConnectionType.QueuedConnection)
+        self._debugFinished.connect(self._handle_debug_finished, Qt.ConnectionType.QueuedConnection)
 
         root_logger = logging.getLogger()
         root_logger.addHandler(QmlActivityLogHandler(self))
@@ -94,18 +111,23 @@ class DeviceController(QObject):
         """Update connection status and notify QML."""
         if self._connection_status != status:
             self._connection_status = status
-            self.portsUpdated.emit(self.availablePorts)
+            self.connectionStatusChanged.emit()
 
-    @Property(str, notify=portsUpdated)
+    @Property(str, notify=connectionStatusChanged)
     def connectionStatus(self) -> str:
         """Current connection status string for display."""
         return self._connection_status
 
-    @Property(bool, notify=portsUpdated)
+    @Property(bool, notify=operationInProgressChanged)
     def operationInProgress(self) -> bool:
         """Whether a hardware operation is currently running."""
         return self._operation_in_progress
 
+    @Property(str, notify=activityLogUpdated)
+    def activityLog(self) -> str:
+        """Full activity log text; survives QML tab reloads."""
+        return "\n".join(self._activity_log)
+
     @Property(str, notify=activityLogUpdated)
     def saveDataDir(self) -> str:
         """Directory where parsed CSV data files are saved."""
@@ -119,7 +141,43 @@ class DeviceController(QObject):
         self._append_log(f"Save data dir set to: {path}")
         self._save_status()
 
-    @Property(str, notify=portsUpdated)
+    @Slot(result=str)
+    @slot_error_boundary
+    def exportDir(self) -> str:
+        """Ensure and return the Export subfolder under saveDataDir."""
+        path = Path(self._save_data_dir) / "Export"
+        path.mkdir(parents=True, exist_ok=True)
+        return str(path)
+
+    @Slot(str)
+    @slot_error_boundary
+    def openCsvFile(self, file_path: str) -> None:
+        """Open a CSV file in the system default spreadsheet application."""
+
+        if not file_path:
+            self._append_log("No file path provided to openCsvFile")
+            return
+
+        try:
+            path = Path(file_path)
+            if not path.exists():
+                self._append_log(f"File not found: {file_path}")
+                return
+
+            # Platform-appropriate file opener
+            if sys.platform == "darwin":
+                subprocess.Popen(["open", str(path)])
+            elif sys.platform == "linux":
+                subprocess.Popen(["xdg-open", str(path)])
+            else:  # Windows
+                os.startfile(str(path))
+
+            self._append_log(f"Opened file: {file_path}")
+        except Exception as exc:
+            log.warning("Failed to open file %s: %s", file_path, exc)
+            self._append_log(f"Error opening file: {exc}")
+
+    @Property(str, notify=selectedPortChanged)
     def selectedPort(self) -> str:
         """Currently selected serial port shared across the UI."""
         return self._selected_port
@@ -128,8 +186,10 @@ class DeviceController(QObject):
     @slot_error_boundary
     def setSelectedPort(self, port: str) -> None:
         """Set the active serial port from the port selector."""
-        self._selected_port = port
-        self._save_status()
+        if self._selected_port != port:
+            self._selected_port = port
+            self.selectedPortChanged.emit()
+            self._save_status()
 
     @Property(int, notify=parsedDataReady)
     def dataRowCount(self) -> int:
@@ -164,6 +224,17 @@ class DeviceController(QObject):
             info.get("cycleCount", 0),
         ]
 
+    @Property(bool, notify=waferDetectedChanged)
+    def waferDetected(self) -> bool:
+        """Whether a wafer is currently detected and ready for read/erase."""
+        return self._wafer_detected
+
+    def _set_wafer_detected(self, detected: bool) -> None:
+        if self._wafer_detected != detected:
+            self._wafer_detected = detected
+            self.waferDetectedChanged.emit()
+
+
     @Property(object, notify=detectResult)
     def dataModel(self) -> TemperatureTableModel:
         """QAbstractTableModel for the parsed temperature data table."""
@@ -228,6 +299,7 @@ class DeviceController(QObject):
         self._set_connection_status("Disconnected")
         self._selected_port = ""
         self._last_wafer_info = {}
+        self._set_wafer_detected(False)
         self._data_row_count = 0
         self._data_col_count = 0
         self._raw_bytes = None
@@ -243,14 +315,10 @@ class DeviceController(QObject):
 
 
     def _set_operation_progress(self, in_progress: bool) -> None:
-        """Set operation progress state and notify QML.
-
-        portsUpdated is the shared notify signal for availablePorts,
-        connectionStatus, and operationInProgress — emitting it forces
-        QML to re-evaluate all three bindings.
-        """
-        self._operation_in_progress = in_progress
-        self.portsUpdated.emit(self._service.enumerate_ports())
+        """Set operation progress state and notify QML."""
+        if self._operation_in_progress != in_progress:
+            self._operation_in_progress = in_progress
+            self.operationInProgressChanged.emit()
 
     # ---- Public Slots ----
 
@@ -258,6 +326,7 @@ class DeviceController(QObject):
     @slot_error_boundary
     def refreshPorts(self) -> None:
         """Scan for available serial ports and emit updated list."""
+        self._service.clear_port_scan_cache()
         ports = self._service.enumerate_ports()
         self._set_connection_status("Disconnected")
         self.portsUpdated.emit(ports)
@@ -287,6 +356,7 @@ class DeviceController(QObject):
         self._graph_view.resetChart()
         self._activity_log.clear()
         self.detectResult.emit(None)
+        self.selectedPortChanged.emit()
         self.parsedDataReady.emit({"success": False})
 
         self._set_operation_progress(True)
@@ -312,20 +382,29 @@ class DeviceController(QObject):
         self, port: Optional[str], info: Optional[WaferInfo]
     ) -> None:
         """Main-thread completion handler for detectWafer."""
-        if info is not None:
-            self._selected_port = port or ""
-            self._set_connection_status("Connected")
-            wafer_dict = self._wafer_info_to_dict(info)
-            self._last_wafer_info = wafer_dict
-            self.detectResult.emit(wafer_dict)
-            self._save_status()
-        else:
-            self._selected_port = ""
-            self._set_connection_status("Disconnected")
-            self._append_log("No wafer detected on any port")
-            self._last_wafer_info = {}
-            self.detectResult.emit(None)
-        self._set_operation_progress(False)
+        try:
+            if info is not None:
+                # Build the dict (can raise) before declaring success, so a
+                # bad payload can't leave status="Connected" while
+                # waferDetected stays false and Read/Erase stay greyed.
+                wafer_dict = self._wafer_info_to_dict(info)
+                self._selected_port = port or ""
+                self._last_wafer_info = wafer_dict
+                self._set_wafer_detected(True)
+                self._set_connection_status("Connected")
+                self.detectResult.emit(wafer_dict)
+                self.selectedPortChanged.emit()
+                self._save_status()
+            else:
+                self._selected_port = ""
+                self._set_connection_status("Disconnected")
+                self._append_log("No wafer detected on any port")
+                self._last_wafer_info = {}
+                self._set_wafer_detected(False)
+                self.detectResult.emit(None)
+                self.selectedPortChanged.emit()
+        finally:
+            self._set_operation_progress(False)
 
     @Slot()
     @slot_error_boundary
@@ -340,6 +419,16 @@ class DeviceController(QObject):
             self._append_log("Already busy — ignoring read request")
             return
 
+        # TODO P2.1: license guard —
+        #   if self._wafer_license_level() == "":
+        #       self._append_log("Wafer not licensed — load its license .bin (About dialog)")
+        #       self.readResult.emit({"error": "Wafer not licensed"})
+        #       return
+        #   THINKING: this slot is the trust boundary; the QML enabled
+        #   binding (P2.2) is UX only. Reuses existing readResult error
+        #   shape → zero new signals. Depends on P1.2. Same guard goes in
+        #   eraseMemory (emit eraseResult there). See plan §2.1.
+
         if not self._selected_port:
             self._append_log("No wafer detected — run Detect Wafer first")
             self.readResult.emit({"error": "No port — detect wafer first"})
@@ -396,12 +485,36 @@ class DeviceController(QObject):
     @slot_error_boundary
     def eraseMemory(self, port: str) -> None:
         """Send p1 erase command."""
+        if self._operation_in_progress:
+            self._append_log("Already busy — ignoring erase request")
+            return
+
+        # TODO P2.1: same license guard as readMemoryAsync, but emit
+        #   self.eraseResult.emit({"success": False}) on denial. See plan §2.1.
         self._set_operation_progress(True)
         self._set_connection_status("Erasing...")
         self.portsUpdated.emit(self._service.enumerate_ports())
         self._append_log(f"Erase command sent to {port} (wafer takes ~15s) ...")
 
-        ok = self._service.erase_wafer(port)
+        threading.Thread(
+            target=self._erase_worker,
+            args=(port,),
+            daemon=True,
+        ).start()
+
+    def _erase_worker(self, port: str) -> None:
+        """Background thread worker for eraseMemory."""
+        try:
+            ok = self._service.erase_wafer(port)
+        except Exception as exc:
+            log.exception("Erase worker crashed: %s", exc)
+            ok = False
+        self._eraseFinished.emit(ok)
+
+    @Slot(bool)
+    @slot_error_boundary
+    def _handle_erase_finished(self, ok: bool) -> None:
+        """Main thread completion handler for eraseMemory."""
         if ok:
             self._set_connection_status("Connected")
             self._append_log("Erase command accepted — wait ~15 seconds")
@@ -414,45 +527,83 @@ class DeviceController(QObject):
     @Slot(str)
     @slot_error_boundary
     def readDebug(self, port: str) -> None:
-        """Read both D1 (sensor) and F1 (debug/cold-junction) data.
-
-        Emits debugResult with counts on success.
-        """
+        """Read both D1 (sensor) and F1 (debug/cold-junction) data."""
+        if self._operation_in_progress:
+            self._append_log("Already busy — ignoring debug read request")
+            return
         self._set_operation_progress(True)
         self._set_connection_status("Reading debug...")
         self.portsUpdated.emit(self._service.enumerate_ports())
         self._append_log(f"Reading debug data on {port} ...")
 
-        # Step 1: D1 sensor data
-        sensor_data = self._service.read_wafer_data(port, family_code="")
-        if sensor_data is None:
+        threading.Thread(
+            target=self._debug_worker,
+            args=(port,),
+            daemon=True,
+        ).start()
+
+    def _debug_worker(self, port: str) -> None:
+        """Background thread worker for readDebug."""
+        try:
+            # Step 1: D1 sensor data
+            sensor_data = self._service.read_wafer_data(port, family_code="")
+            if sensor_data is None:
+                self._debugFinished.emit({"error": "D1 read failed"})
+                return
+
+            # Step 2: F1 debug data
+            debug_data = self._service.read_wafer_data(port, family_code="", cmd="F1")
+            if debug_data is None:
+                self._debugFinished.emit({"error": "F1 read failed"})
+                return
+
+            fc = (
+                self._last_wafer_info.get("familyCode", "")
+                if self._last_wafer_info
+                else ""
+            )
+            sensor_hex = parse_binary_data(sensor_data, fc)
+            debug_hex = parse_binary_data(debug_data, fc)
+            if not sensor_hex or not debug_hex:
+                self._debugFinished.emit({"error": "Debug binary parse failed"})
+                return
+
+            temp_data = convert_to_temperatures(sensor_hex, fc)
+            debug_temp_data = convert_to_debug_temperatures(debug_hex)
+            csv_path = save_debug_csv(temp_data, debug_temp_data, self._save_data_dir)
+            if csv_path is None:
+                self._debugFinished.emit({"error": "Debug CSV save failed"})
+                return
+
+            self._debugFinished.emit({
+                "success": True,
+                "sensor_bytes": len(sensor_data),
+                "debug_bytes": len(debug_data),
+                "csv_path": csv_path,
+            })
+        except Exception as exc:
+            log.exception("Debug worker crashed: %s", exc)
+            self._debugFinished.emit({"error": str(exc)})
+
+    @Slot(dict)
+    @slot_error_boundary
+    def _handle_debug_finished(self, result: dict) -> None:
+        """Main thread completion handler for readDebug."""
+        if result.get("success"):
+            self._set_connection_status("Connected")
+            sensor_bytes = result.get("sensor_bytes", 0)
+            debug_bytes = result.get("debug_bytes", 0)
+            csv_path = result.get("csv_path", "")
+            msg = f"Debug read complete: {sensor_bytes} sensor bytes, {debug_bytes} debug bytes"
+            if csv_path:
+                msg += f", CSV written to {csv_path}"
+            self._append_log(msg)
+        else:
             self._set_connection_status("Disconnected")
-            self._append_log("D1 read failed — aborting debug read")
-            self.debugResult.emit({"error": "D1 read failed"})
-            self._set_operation_progress(False)
-            return
+            err_msg = result.get("error", "Debug read failed")
+            self._append_log(err_msg)
 
-        self._append_log(f"D1 read: {len(sensor_data)} bytes")
-
-        # Step 2: F1 debug data
-        debug_data = self._service.read_wafer_data(port, family_code="", cmd="F1")
-        if debug_data is None:
-            self._set_connection_status("Disconnected")
-            self._append_log("F1 read failed")
-            self.debugResult.emit({"error": "F1 read failed"})
-            self._set_operation_progress(False)
-            return
-
-        self._set_connection_status("Connected")
-        self._append_log(
-            f"Debug read complete: {len(sensor_data)} sensor bytes, "
-            f"{len(debug_data)} debug bytes"
-        )
-        self.debugResult.emit({
-            "success": True,
-            "sensor_bytes": len(sensor_data),
-            "debug_bytes": len(debug_data),
-        })
+        self.debugResult.emit(result)
         self._set_operation_progress(False)
 
     @Slot(str, str)
@@ -472,7 +623,6 @@ class DeviceController(QObject):
             return
 
         if not self._save_data_dir:
-            from pathlib import Path
             self._save_data_dir = str(Path(self._data_dir) / "csv")
             self._append_log(f"Auto-set save directory to: {self._save_data_dir}")
             self._save_status()

src/pygui/backend/controllers/session_controller.py

@@ -11,12 +11,17 @@ from PySide6.QtCore import Property, QObject, Qt, QTimer, Signal, Slot
 from pygui.backend.cluster_average import average_clusters, group_sensors_by_radius
 from pygui.backend.data.csv_recorder import CsvRecorder
 from pygui.backend.models.frame import Frame
-from pygui.backend.models.frame_player import FramePlayer, frames_from_wafer_data
-from pygui.backend.models.replay_stats import ReplayStatsTracker
+from pygui.backend.models.frame_player import (
+    FramePlayer,
+    all_sensor_series,
+    frames_from_wafer_data,
+)
+from pygui.backend.models.frame_stats import compute_edge_center
 from pygui.backend.models.sensor_editor import SensorEditor
-from pygui.backend.models.session_model import SessionModel
+from pygui.backend.models.session_model import SessionModel, SessionUpdate
 from pygui.backend.models.threshold_classifier import ThresholdConfig
 from pygui.backend.utils import slot_error_boundary
+from pygui.backend.wafer.wafer_layouts import ec_pairs_for_wafer_id
 from pygui.backend.wafer.zwafer_models import Sensor
 from pygui.backend.wafer.zwafer_parser import ZWaferParser
 from pygui.serialcomm.stream_reader import StreamReader
@@ -35,17 +40,22 @@ class SessionController(QObject):
     recordingChanged = Signal()
     sensorsChanged = Signal()
     loadedFileChanged = Signal()
+    loadFileError = Signal(str)
     clusterAveragingEnabledChanged = Signal()
-    settingsChanged = Signal()  # emitted when session state changes that should be persisted
     liveStatsChanged = Signal()  # emitted when receivedCount or errorCount change
     # trend: per-frame avg for live graph
-    trendData = Signal(str)  # JSON array of floats
+    trendDelta = Signal(str)  # JSON [[elapsed_s, avg]] — one new point per live frame
+    trendReset = Signal()  # live trend buffer cleared (new stream started)
+    # NOTE: dict (QVariantMap), not object — Signal(object) delivers Python
+    # dicts to QML as an opaque empty wrapper with no accessible fields.
+    comparisonResult = Signal(dict)  # dict with success, distance, warping_path, max_sensor_deviation, series_a, series_b
+    splitResult = Signal(dict)  # dict with success, segments
+    segmentExported = Signal(dict)  # dict with success, path | error
     # private: marshal a worker-thread frame onto the main thread
     _liveFrame = Signal(object)    # Frame
     _liveError = Signal()          # worker-thread error ping
 
-    def __init__(self, parent: QObject | None = None,
-                 settings: dict | None = None) -> None:
+    def __init__(self, parent: QObject | None = None) -> None:
         super().__init__(parent)
         self._mode = MODE_REVIEW
         self._model = SessionModel()
@@ -53,15 +63,9 @@ class SessionController(QObject):
         self._reader: Optional[StreamReader] = None
         self._recorder = CsvRecorder()
         self._sensors: list[Sensor] = []
-        self._last = None              # last SessionUpdate
+        self._last: Optional[SessionUpdate] = None
         self._elapsed = 0.0
-        self._trend_buffer: list[float] = [] # rolling window
-        self._trend_timestamps: list[float] = []  # monotonic timestamps
-
-        # Trend refresh timer - update every 1s
-        self._trend_timer = QTimer(self)
-        self._trend_timer.setInterval(1000)
-        self._trend_timer.timeout.connect(self._flush_trend)
+        self._stream_start_time: float = 0.0
 
         self._play_timer = QTimer(self)
         self._play_timer.timeout.connect(self._advance)
@@ -77,28 +81,18 @@ class SessionController(QObject):
         self._liveError.connect(self._on_live_error, Qt.ConnectionType.QueuedConnection)
 
         self._sensor_editor = SensorEditor()
+        self._ec_pairs: tuple[tuple[int, int], ...] = ()
         self._last_raw_frame: Frame | None = None
         self._loaded_file: str = ""
         self._cluster_averaging_enabled = False
         self._active_clusters: list[list[int]] = []
-        self._stats_tracker = ReplayStatsTracker()
         self._received_count: int = 0
         self._error_count: int = 0
 
-        # Restore persisted state if available
-        self._load_settings(settings or {})
-
-    # ---- persisted settings ----
-
-    def _load_settings(self, settings: dict) -> None:
-        """Restore session state from persisted settings dict."""
-        # Do NOT auto-restore the last session file — always start fresh.
-
-    def collect_settings(self) -> dict:
-        """Return a dict of session state to persist."""
-        return {
-            "session_last_file": self._loaded_file,
-        }
+        # Comparison cache for dynamic overlap mapping
+        self._compare_recs_a: list = []
+        self._compare_recs_b: list = []
+        self._compare_alignment_map: dict[int, int] = {}
 
     # ---- properties QML binds to ----
     @Property(str, notify=modeChanged)
@@ -139,7 +133,7 @@ class SessionController(QObject):
                         "value": round(v, 2), "band": band, "index": i})
         return out
 
-    @Property("QVariantList", notify=sensorsChanged)
+    @Property("QVariantList", notify=sensorsChanged)  # type: ignore[arg-type]
     def sensorLayout(self) -> list:
         """[{label, x, y, side, offset_x, offset_y}] for WaferMapItem.sensors."""
         return [
@@ -164,14 +158,14 @@ class SessionController(QObject):
         """Wafer size in mm."""
         return getattr(self._sensors, "size", 300.0)
 
-    @Property("QVariantList", notify=frameUpdated)
+    @Property("QVariantList", notify=frameUpdated)  # type: ignore[arg-type]
     def sensorValues(self) -> list:
         """[float] in sensor order."""
         if not self._last:
             return []
         return [round(v, 3) for v in self._last.values]
 
-    @Property("QVariantList", notify=frameUpdated)
+    @Property("QVariantList", notify=frameUpdated)  # type: ignore[arg-type]
     def sensorBands(self) -> list:
         """['in_range'|'high'|'low'] in sensor order."""
         if not self._last:
@@ -193,15 +187,43 @@ class SessionController(QObject):
         if not self._last:
             return {}
         s = self._last.stats
-        return {"min": round(s.min, 2), "minIndex": s.min_index + 1,
-                "max": round(s.max, 2), "maxIndex": s.max_index + 1,
-                "diff": round(s.diff, 2), "avg": round(s.avg, 2),
-                "sigma": round(s.sigma, 2), "threeSigma": round(s.three_sigma, 2)}
+        out = {"min": round(s.min, 2), "minIndex": s.min_index + 1,
+               "max": round(s.max, 2), "maxIndex": s.max_index + 1,
+               "diff": round(s.diff, 2), "avg": round(s.avg, 2),
+               "sigma": round(s.sigma, 2), "threeSigma": round(s.three_sigma, 2)}
+        ec = compute_edge_center(self._last.values, self._ec_pairs,
+                                 self._sensor_editor.replaced_indices())
+        if ec is not None:
+            out.update({
+                "ecMinEdgeIndex": ec.min_edge_index + 1,
+                "ecMinCenterIndex": ec.min_center_index + 1,
+                "ecMinEdgeValue": round(ec.min_edge, 2),
+                "ecMinCenterValue": round(ec.min_center, 2),
+                "ecMinDelta": round(ec.min_delta, 2),
+                "ecMaxEdgeIndex": ec.max_edge_index + 1,
+                "ecMaxCenterIndex": ec.max_center_index + 1,
+                "ecMaxEdgeValue": round(ec.max_edge, 2),
+                "ecMaxCenterValue": round(ec.max_center, 2),
+                "ecMaxDelta": round(ec.max_delta, 2),
+            })
+        return out
 
     @Property(str, notify=loadedFileChanged)
     def loadedFile(self) -> str: return self._loaded_file
 
-    @Property("QVariantList", notify=frameUpdated)
+    @Property(str, notify=loadedFileChanged)
+    def graphSensorNames(self) -> str:
+        """Comma-joined sensor names for the whole-run Graph tab."""
+        names, _ = all_sensor_series(list(self._player.frames))
+        return ",".join(names)
+
+    @Property(str, notify=loadedFileChanged)
+    def graphSeriesJson(self) -> str:
+        """JSON per-sensor value series (one list per sensor) for the Graph tab."""
+        _, series = all_sensor_series(list(self._player.frames))
+        return json.dumps(series)
+
+    @Property("QVariantList", notify=frameUpdated)  # type: ignore[arg-type]
     def overriddenSensors(self) -> list[int]:
         """Indices of sensors that currently have a replacement or offset."""
         return self._sensor_editor.active_indices()
@@ -210,7 +232,7 @@ class SessionController(QObject):
     def clusterAveragingEnabled(self) -> bool:
         return self._cluster_averaging_enabled
 
-    @clusterAveragingEnabled.setter
+    @clusterAveragingEnabled.setter  # type: ignore[no-redef]
     def clusterAveragingEnabled(self, value: bool) -> None:
         if self._cluster_averaging_enabled == value:
             return
@@ -226,13 +248,24 @@ class SessionController(QObject):
     def errorCount(self) -> int:
         return self._error_count
 
+    @Property(int, notify=liveStatsChanged)
+    def resyncCount(self) -> int:
+        return self._reader.resync_count if self._reader else 0
+
     # ---- mode + thresholds ----
     @Slot(str)
     @slot_error_boundary
     def setMode(self, mode: str) -> None:
         if mode == self._mode:
             return
-        self.stopStream()
+        if mode != "live":
+            self.stopStream()
+            if self._mode == "live":
+                # Leaving a live session: blank the wafer map instead of
+                # freezing the last streamed frame on screen.
+                self._last = None
+                self._last_raw_frame = None
+                self.frameUpdated.emit()
         self._play_timer.stop()
         self._mode = mode
         self.modeChanged.emit()
@@ -259,24 +292,25 @@ class SessionController(QObject):
 
         frames = []
 
-        if is_official_csv(file_path):
-            sensors, records = read_official_csv(file_path)
-            frames = frames_from_wafer_data(None, records)
-        else:
-            try:
+        try:
+            if is_official_csv(file_path):
+                sensors, records = read_official_csv(file_path)
+                frames = frames_from_wafer_data(None, records)
+            else:
                 data, _ = ZWaferParser().parse(file_path)
-            except (ValueError, KeyError) as exc:
-                log.warning("Could not parse %s: %s", file_path, exc)
-                return
-            if data is None or not data.sensors:
-                log.warning("Could not parse %s", file_path)
-                return
-            records = read_data_records(file_path)
-            sensors = data.sensors
-            frames = frames_from_wafer_data(data, records)
+                if data is None or not data.sensors:
+                    self.loadFileError.emit("Invalid layout or missing sensors in custom CSV.")
+                    return
+                records = read_data_records(file_path)
+                sensors = data.sensors
+                frames = frames_from_wafer_data(data, records)
 
-        if not sensors or not frames:
-            log.warning("No sensors or data in %s", file_path)
+            if not sensors or not frames:
+                self.loadFileError.emit("No sensors or frames found in data file.")
+                return
+        except Exception as exc:
+            log.warning("Could not parse file %s: %s", file_path, exc)
+            self.loadFileError.emit(f"Load error: {exc}")
             return
 
         wafer_id = ""
@@ -287,22 +321,270 @@ class SessionController(QObject):
             wafer_id = stem.split("-")[0] if "-" in stem else stem
 
         shape, size = resolve_shape_and_size(sensors, wafer_id)
+        self._ec_pairs = ec_pairs_for_wafer_id(wafer_id)
         self._sensors = WaferLayout(sensors, shape=shape, size=size)
         self._active_clusters = getattr(self._sensors, 'clusters', [])
         if not self._active_clusters:
             self._active_clusters = group_sensors_by_radius(self._sensors)
         self._player.load(frames)
         self._model.reset()
-        self._stats_tracker.reset()
         self._loaded_file = file_path
         self.loadedFileChanged.emit()
         self.sensorsChanged.emit()
         self._emit_current()
-        # Populate stats tracker from all loaded frames for trend chart (P3.1)
-        for frame in self._player._frames:
-            self._stats_tracker.track(frame.seq, frame.values)
-        self.trendData.emit(json.dumps(self._stats_tracker.get_trend()))
-        self.settingsChanged.emit()
+
+    @Slot()
+    @slot_error_boundary
+    def unloadFile(self) -> None:
+        """Clear the loaded file, resetting the player and frame states."""
+        self._player.load([])
+        self._model.reset()
+        self._ec_pairs = ()
+        self._loaded_file = ""
+        self.loadedFileChanged.emit()
+        self.sensorsChanged.emit()
+
+    # ---- comparison: DTW between two CSV files ----
+    @Slot(str, str)
+    @slot_error_boundary
+    def compareFiles(self, file_a: str, file_b: str) -> None:
+        """Run DTW comparison between two CSV files and emit result."""
+        from pathlib import Path
+
+        from pygui.backend.comparison import compare_runs
+        from pygui.backend.data.data_records import is_official_csv, read_data_records, read_official_csv
+
+        if Path(file_a).resolve() == Path(file_b).resolve():
+            self.comparisonResult.emit({
+                "success": False,
+                "error": "Cannot compare a file to itself. Choose two different runs."
+            })
+            return
+
+        try:
+            if is_official_csv(file_a):
+                _, recs_a = read_official_csv(file_a)
+            else:
+                recs_a = read_data_records(file_a)
+
+            if is_official_csv(file_b):
+                _, recs_b = read_official_csv(file_b)
+            else:
+                recs_b = read_data_records(file_b)
+            if not recs_a or not recs_b:
+                self.comparisonResult.emit({
+                    "success": False,
+                    "error": "No data in one or both files"
+                })
+                return
+
+            self._compare_recs_a = recs_a
+            self._compare_recs_b = recs_b
+
+            len_a, len_b = len(recs_a), len(recs_b)
+            # DTW can only align frames both runs actually have; the longer
+            # run's extra tail is still returned for display, just unaligned.
+            overlap_frames = min(len_a, len_b)
+            series_a = [recs_a[i].values[0] if recs_a[i].values else 0.0 for i in range(len_a)]
+            series_b = [recs_b[i].values[0] if recs_b[i].values else 0.0 for i in range(len_b)]
+            time_a = [round(recs_a[i].time, 3) for i in range(len_a)]
+            time_b = [round(recs_b[i].time, 3) for i in range(len_b)]
+
+            result = compare_runs(series_a[:overlap_frames], series_b[:overlap_frames])
+            self._compare_alignment_map = {i: j for i, j in result["warping_path"]}
+
+            # Mean temporal shift along the DTW path: positive means run B
+            # reaches the same profile features later than run A.
+            path = result["warping_path"]
+            frame_offset = round(sum(j - i for i, j in path) / len(path)) if path else 0
+            frame_offset_seconds = round(
+                sum(time_b[j] - time_a[i] for i, j in path) / len(path), 2
+            ) if path else 0.0
+
+            # Max sensor deviation: walk the DTW-aligned frame pairs (bounded to
+            # the overlap both runs share) and take the largest per-sensor abs
+            # difference across all sensors, not just the sensor[0] series used
+            # for alignment.
+            num_sensors = min(len(recs_a[0].values), len(recs_b[0].values)) if recs_a[0].values and recs_b[0].values else 0
+            max_sensor_deviation = 0.0
+            for i, j in zip(result["index_a"], result["index_b"]):
+                values_a = recs_a[i].values
+                values_b = recs_b[j].values
+                for s in range(min(num_sensors, len(values_a), len(values_b))):
+                    diff = abs(values_a[s] - values_b[s])
+                    if diff > max_sensor_deviation:
+                        max_sensor_deviation = diff
+
+            # Sensor layout + per-sensor diff for the wafer overlap view. Reuses the
+            # same sensor-parsing branch as loadFile() (file_a is assumed representative
+            # of both files' wafer type).
+            from pygui.backend.wafer.wafer_layouts import resolve_shape_and_size
+            from pygui.backend.wafer.zwafer_parser import ZWaferParser
+
+            sensor_layout: list[dict] = []
+            sensor_diff: list[float] = []
+            wafer_shape = "round"
+            wafer_size = 300.0
+            try:
+                if is_official_csv(file_a):
+                    sensors, _ = read_official_csv(file_a)
+                    stem = Path(file_a).stem
+                    wafer_id = stem.split("-")[0] if "-" in stem else stem
+                else:
+                    parsed, _ = ZWaferParser().parse(file_a)
+                    sensors = parsed.sensors if parsed else []
+                    wafer_id = parsed.serial if (parsed and parsed.serial) else ""
+
+                if sensors:
+                    wafer_shape, wafer_size = resolve_shape_and_size(sensors, wafer_id)
+                    last_a = recs_a[overlap_frames - 1].values
+                    last_b = recs_b[overlap_frames - 1].values
+                    n = min(len(sensors), len(last_a), len(last_b))
+                    sensor_layout = [
+                        {
+                            "label": s.label,
+                            "x": s.x,
+                            "y": s.y,
+                            "side": getattr(s, "side", "right"),
+                            "offset_x": getattr(s, "offset_x", 0.0),
+                            "offset_y": getattr(s, "offset_y", 0.0),
+                        }
+                        for s in sensors[:n]
+                    ]
+                    sensor_diff = [round(last_b[i] - last_a[i], 3) for i in range(n)]
+            except Exception as layout_exc:
+                log.warning("Could not resolve sensor layout for overlap view: %s", layout_exc)
+
+            self.comparisonResult.emit({
+                "success": True,
+                "distance": result["distance"],
+                # Lists, not tuples — tuples don't survive QVariant conversion
+                "warping_path": [list(p) for p in result["warping_path"][:50]],
+                "frame_offset": frame_offset,
+                "frame_offset_seconds": frame_offset_seconds,
+                "max_sensor_deviation": max_sensor_deviation,
+                "series_a": series_a,
+                "series_b": series_b,
+                "time_a": time_a,
+                "time_b": time_b,
+                "frame_count_a": len_a,
+                "frame_count_b": len_b,
+                "sensor_layout": sensor_layout,
+                "sensor_diff": sensor_diff,
+                "wafer_shape": wafer_shape,
+                "wafer_size": wafer_size,
+            })
+        except Exception as exc:
+            log.warning("Comparison failed: %s", exc)
+            self.comparisonResult.emit({
+                "success": False,
+                "error": str(exc)
+            })
+
+    @Slot(int, result="QVariantList")
+    def getSensorDiffAt(self, scrub_idx: int) -> list[float]:
+        """Return the per-sensor temp diff (Run B - Run A) at the given scrub frame index of Run A, using DTW alignment."""
+        if not self._compare_recs_a or not self._compare_recs_b:
+            return []
+
+        idx_a = min(max(0, scrub_idx), len(self._compare_recs_a) - 1)
+        if idx_a not in self._compare_alignment_map:
+            # DTW path only covers indices up to the shorter run's length —
+            # past that, Run B has no data at this frame, not a clampable one.
+            return []
+        idx_b = self._compare_alignment_map[idx_a]
+
+        values_a = self._compare_recs_a[idx_a].values
+        values_b = self._compare_recs_b[idx_b].values
+
+        n = min(len(values_a), len(values_b))
+        return [round(values_b[i] - values_a[i], 3) for i in range(n)]
+
+    # ---- splitting: threshold-based segmentation ----
+    @Slot(str, float)
+    @slot_error_boundary
+    def splitData(self, file_path: str, threshold: float) -> None:
+        """Segment temperature profile into Ramp/Soak/Cool phases."""
+        from pygui.backend.data.data_records import is_official_csv, read_data_records, read_official_csv
+        from pygui.backend.splitter import segment_profile
+
+        try:
+            if is_official_csv(file_path):
+                _, records = read_official_csv(file_path)
+            else:
+                records = read_data_records(file_path)
+            if not records:
+                self.splitResult.emit({
+                    "success": False,
+                    "error": "No data in file"
+                })
+                return
+
+            # Extract average temperatures (use first sensor as proxy)
+            avg_temps = [rec.values[0] if rec.values else 0.0 for rec in records]
+            segments = segment_profile(avg_temps, threshold)
+
+            # cache for exportSegment (per-segment Export in SplitDialog)
+            self._last_split_file = file_path
+            self._last_split_segments = segments
+
+            self.splitResult.emit({
+                "success": True,
+                "segments": [{
+                    "label": seg.label,
+                    "start_frame": seg.start_frame,
+                    "end_frame": seg.end_frame,
+                    "avg_temp": seg.avg_temp
+                } for seg in segments]
+            })
+        except Exception as exc:
+            log.warning("Split failed: %s", exc)
+            self.splitResult.emit({
+                "success": False,
+                "error": str(exc)
+            })
+
+    @Slot(int)
+    @slot_error_boundary
+    def exportSegment(self, index: int) -> None:
+        """Write one segment from the last split as a standalone CSV.
+
+        Output lands next to the source file as
+        ``<stem>_<label><index>.csv`` — the stem keeps its wafer-id prefix
+        so read_official_csv still resolves the layout on re-import.
+        Emits segmentExported with success + path (or error).
+        """
+        from pathlib import Path
+
+        from pygui.backend.data.csv_recorder import CsvRecorder
+
+        source = getattr(self, "_last_split_file", "")
+        segments = getattr(self, "_last_split_segments", [])
+        if not source or not (0 <= index < len(segments)):
+            self.segmentExported.emit({
+                "success": False,
+                "error": "No split result to export"
+            })
+            return
+
+        seg = segments[index]
+        src = Path(source)
+        dest = src.with_name(f"{src.stem}_{seg.label.lower()}{index + 1}.csv")
+        try:
+            ok = CsvRecorder.write_segment(
+                str(dest), str(src), seg.start_frame, seg.end_frame)
+        except Exception as exc:
+            log.warning("Segment export failed: %s", exc)
+            self.segmentExported.emit({"success": False, "error": str(exc)})
+            return
+
+        if ok:
+            self.segmentExported.emit({"success": True, "path": str(dest)})
+        else:
+            self.segmentExported.emit({
+                "success": False,
+                "error": "No frames in range"
+            })
 
     @Slot()
     @slot_error_boundary
@@ -394,6 +676,9 @@ class SessionController(QObject):
     @Slot(str, str)
     @slot_error_boundary
     def startStream(self, port: str, family_code: str = "") -> None:
+        if self._reader is not None:
+            log.warning("startStream: StreamReader is already running.")
+            return
 
         from pygui.backend.wafer.wafer_layouts import load_layout_for_wafer_id
         from pygui.serialcomm.serial_port import SerialPort  # transport open
@@ -404,6 +689,7 @@ class SessionController(QObject):
                 self.sensorsChanged.emit()
             except Exception as e:
                 log.warning("Could not load layout for %s: %s", family_code, e)
+        self._ec_pairs = ec_pairs_for_wafer_id(family_code)
 
         self._active_clusters = getattr(self._sensors, 'clusters', [])
         if not self._active_clusters:
@@ -434,10 +720,7 @@ class SessionController(QObject):
 
         # Clear out any old data from the prev sessions
         self._model.reset()
-        self._trend_buffer.clear()
-        self._trend_timestamps.clear()
-        self._trend_timer.start()
-        self._stats_tracker.reset()
+        self._reset_live_trend()
         self._last = None
         self._last_raw_frame = None
         self._received_count = 0
@@ -449,13 +732,24 @@ class SessionController(QObject):
         cmd = b"D2" + SerialPort.COMMAND_PAD.encode()
         transport.write(cmd)
 
+        import weakref
+        weak_self = weakref.ref(self)
+
         def on_error(exc: Exception):
             log.error("Live stream error: %s", exc)
-            self._liveError.emit()
+            ref = weak_self()
+            if ref is not None:
+                ref._liveError.emit()
+                ref.stopStream()
+
+        def on_frame(frame: Frame):
+            ref = weak_self()
+            if ref is not None:
+                ref._liveFrame.emit(frame)
 
         self._reader = StreamReader(
             transport, parse_binary_frame,
-            on_frame=lambda f: self._liveFrame.emit(f),
+            on_frame=on_frame,
             on_error=on_error,
             family_code=family_code or "A")
         self._reader.start()
@@ -468,16 +762,14 @@ class SessionController(QObject):
     @slot_error_boundary
     def stopStream(self) -> None:
         self._repaint_timer.stop()
-        self._trend_timer.stop()
         self._received_count = 0
         self._error_count = 0
         self.liveStatsChanged.emit()
         if self._reader:
             transport = self._reader._transport
-            self._reader.stop()
-            self._reader = None
 
             # Send 'D2S' command padded to 512 bytes to stop the stream
+            # Send BEFORE stopping the reader which will close the port on thread exit
             if transport and transport.is_open:
                 try:
                     cmd = b"D2S" + (b"F" * 509)
@@ -486,16 +778,17 @@ class SessionController(QObject):
                 except Exception as exc:
                     log.error("Error sending stop command: %s", exc)
 
+            self._reader.stop()
+            self._reader = None
+
         self.stateChanged.emit()
         self.stopRecording()
 
     @Slot(object)
     @slot_error_boundary
     def _on_live_frame(self, frame: Frame) -> None:
-        import json
         self._received_count += 1
         self.liveStatsChanged.emit()
-        self._stats_tracker.track(frame.seq, frame.values)
         # Main thread (queued). Record raw, process edited; mark dirty for repaint.
         self._last_raw_frame = frame
         edited = Frame(seq=frame.seq, time=frame.time,
@@ -504,22 +797,11 @@ class SessionController(QObject):
         if self._recorder.is_recording:
             self._recorder.write(frame)   # always record raw values, never edited
         self._dirty = True
-        self.trendData.emit(json.dumps(self._stats_tracker.get_trend()))
 
         if self._last and self._last.stats:
             avg = self._last.stats.avg
-            now = time.monotonic()
-            self._trend_buffer.append(avg)
-            self._trend_timestamps.append(now)
-
-            # drop entries older than 60 secs
-            cutoff = now -60
-            while self._trend_timestamps and self._trend_timestamps[0] < cutoff:
-                self._trend_timestamps.pop(0)
-                self._trend_buffer.pop(0)
-
-
-
+            elapsed = time.monotonic() - self._stream_start_time
+            self.trendDelta.emit(json.dumps([[elapsed, avg]]))
 
     def _flush_repaint(self) -> None:
         if not self._dirty:
@@ -575,8 +857,8 @@ class SessionController(QObject):
         self._sensor_editor.clear()
         self._reprocess_current()
 
-    def _flush_trend(self) -> None:
-        import json
-        self.trendData.emit(json.dumps(self._trend_buffer))
-
+    def _reset_live_trend(self) -> None:
+        """Mark a fresh stream start for elapsed-time trend deltas."""
+        self._stream_start_time = time.monotonic()
+        self.trendReset.emit()
 

src/pygui/backend/crypto/__init__.py

@@ -1,2 +0,0 @@
-# ===== Crypto Sub-package =====
-from pygui.backend.crypto.crypto_helper import *  # noqa: F403

src/pygui/backend/data/__init__.py

@@ -1,14 +0,0 @@
-# ===== Data Sub-package =====
-from pygui.backend.data.csv_file_metadata import CSVFileMetadata
-from pygui.backend.data.csv_recorder import CsvRecorder
-from pygui.backend.data.data_records import is_official_csv, read_data_records, read_official_csv
-from pygui.backend.data.file_browser import FileBrowser
-from pygui.backend.data.local_settings import LocalSettings
-from pygui.backend.data.local_settings_model import LocalSettingsModel
-
-__all__ = [
-    "CsvRecorder", "CSVFileMetadata",
-    "read_data_records", "is_official_csv", "read_official_csv",
-    "FileBrowser",
-    "LocalSettings", "LocalSettingsModel",
-]

src/pygui/backend/data/constants.py

@@ -1,3 +1,14 @@
 # ===== Backend Data Constants =====
 
+from pathlib import Path
+
+from PySide6.QtCore import QStandardPaths
+
 DEFAULT_DATA_DIR_NAME = "isc_data"
+
+
+def default_data_dir() -> Path:
+    """Documents-folder isc_data directory used as the default app data location."""
+    documents_dir = QStandardPaths.writableLocation(QStandardPaths.StandardLocation.DocumentsLocation)
+    base_dir = Path(documents_dir) if documents_dir else (Path.home() / "Documents")
+    return base_dir / DEFAULT_DATA_DIR_NAME

src/pygui/backend/data/csv_file_metadata.py

@@ -19,8 +19,8 @@ class CSVFileMetadata:
         """Return the first character of the wafer string, or empty if none"""
         return self.wafer[0] if self.wafer else ""
 
-    def get_date(self) -> datetime:
-        """Parsifes the date string. Returns current time if parsing fails"""
+    def get_date(self) -> datetime | None:
+        """Parsifes the date string. Returns None if parsing fails"""
         date_format = "%Y-%m-%d %H:%M:%S"
         try:
             return datetime.strptime(self.date, date_format)

src/pygui/backend/data/csv_recorder.py

@@ -1,4 +1,5 @@
 """Append live frames"""
+
 from __future__ import annotations
 
 from datetime import datetime
@@ -12,17 +13,15 @@ from pygui.backend.wafer.zwafer_models import Sensor
 class CsvRecorder:
     def __init__(self) -> None:
         self._file_handle: Optional[TextIO] = None
-        self._oath: Optional[str] = None
-
+        self._path: Optional[str] = None
 
     @property
     def is_recording(self) -> bool:
-            return self._file_handle is not None
+        return self._file_handle is not None
 
-
-    def start(self, path: str, sensors:list[Sensor], serial: str = "") -> None:
+    def start(self, path: str, sensors: list[Sensor], serial: str = "") -> None:
         Path(path).parent.mkdir(parents=True, exist_ok=True)
-        file_handle = open(path, "w", encoding="utf-8", newline ="")
+        file_handle = open(path, "w", encoding="utf-8", newline="")
         file_handle.write(f"Wafer ID={serial}\n")
         file_handle.write(f"Acquisition Date={datetime.now():%m/%d/%Y}\n")
         file_handle.write("Label," + ",".join(s.label for s in sensors) + "\n")
@@ -32,7 +31,7 @@ class CsvRecorder:
         file_handle.flush()
         self._file_handle, self._path = file_handle, path
 
-    def write(self, frame: Frame) ->  None:
+    def write(self, frame: Frame) -> None:
         if self._file_handle is None:
             return
         row = [f"{frame.time:.3f}"] + [f"{v:.3f}" for v in frame.values]
@@ -47,9 +46,15 @@ class CsvRecorder:
         return path
 
     @staticmethod
-    def write_segment(file_path: str, source_path: str, start_frame: int, end_frame: int) ->bool:
+    def write_segment(file_path: str, source_path: str, start_frame: int, end_frame: int) -> bool:
         """Copy a range of frames from source CSV into a new file.
 
+        Preserves the source's header structure so the segment re-imports
+        through FileBrowser unchanged: official CSVs keep their sensor-name
+        row, Z-wafer CSVs keep every metadata line through the "data"
+        sentinel. Frame indices count only valid data rows, matching how
+        the readers in data_records.py number frames.
+
         Args:
             file_path: Output CSV path.
             source_path: Source CSV path with full wafer data
@@ -57,11 +62,42 @@ class CsvRecorder:
             end_frame: Last frame index (inclusive)
 
         Returns:
-            True on success.
+            True on success (at least one frame written).
         """
-        import pandas as pd
-        df = pd.read_csv(source_path)
-        segment = df.iloc[start_frame:end_frame + 1]
-        segment.to_csv(file_path, index=False)
-        return True
+        from pygui.backend.data.data_records import is_data_row, is_official_csv
 
+        if start_frame < 0 or end_frame < start_frame:
+            return False
+
+        with open(source_path, "r", encoding="utf-8") as f:
+            lines = f.readlines()
+
+        out: list[str] = []
+        written = 0
+        frame_idx = -1
+        in_data = is_official_csv(source_path)
+
+        for i, line in enumerate(lines):
+            stripped = line.rstrip().rstrip(",").strip()
+            if not in_data:
+                out.append(line)
+                if stripped and stripped.split(",")[0].lower() == "data":
+                    in_data = True
+                continue
+            if i == 0:
+                # official format: row 0 is the sensor-name header
+                out.append(line)
+                continue
+            if not stripped or not is_data_row(stripped):
+                continue
+            frame_idx += 1
+            if start_frame <= frame_idx <= end_frame:
+                out.append(line if line.endswith("\n") else line + "\n")
+                written += 1
+
+        if written == 0:
+            return False
+        Path(file_path).parent.mkdir(parents=True, exist_ok=True)
+        with open(file_path, "w", encoding="utf-8", newline="") as f:
+            f.writelines(out)
+        return True

src/pygui/backend/data/data_records.py

@@ -1,4 +1,5 @@
 """Read the data section of a Z-wafer CSV into DataRecords, or the official headerless CSV."""
+
 from __future__ import annotations
 
 from pathlib import Path
@@ -6,6 +7,20 @@ from pathlib import Path
 from pygui.backend.wafer.zwafer_models import DataRecord, Sensor
 
 
+def is_data_row(line: str) -> bool:
+    """True if *line* is a single CSV row of numeric values (no headers/metadata)."""
+    cols = [c.strip() for c in line.split(",") if c.strip() != ""]
+    return bool(cols) and all(_is_float(c) for c in cols)
+
+
+def _is_float(s: str) -> bool:
+    try:
+        float(s)
+    except ValueError:
+        return False
+    return True
+
+
 def read_data_records(file_path: str) -> list[DataRecord]:
     records: list[DataRecord] = []
     in_data = False
@@ -18,13 +33,10 @@ def read_data_records(file_path: str) -> list[DataRecord]:
                 if line.split(",")[0].lower() == "data":
                     in_data = True
                 continue
+            if not is_data_row(line):
+                continue
             cols = [c.strip() for c in line.split(",") if c.strip() != ""]
-            try:
-                nums = [float(c) for c in cols]
-            except ValueError:
-                continue
-            if not nums:
-                continue
+            nums = [float(c) for c in cols]
             records.append(DataRecord(time=nums[0], values=nums[1:]))
         return records
 

src/pygui/backend/data/file_browser.py

@@ -5,10 +5,10 @@ import re
 from datetime import datetime
 from pathlib import Path
 
-from PySide6.QtCore import Property, QObject, QStandardPaths, Signal, Slot
+from PySide6.QtCore import Property, QObject, Signal, Slot
 from PySide6.QtWidgets import QFileDialog, QMessageBox
 
-from pygui.backend.data.constants import DEFAULT_DATA_DIR_NAME
+from pygui.backend.data.constants import default_data_dir
 from pygui.backend.data.csv_file_metadata import CSVFileMetadata
 from pygui.backend.wafer.zwafer_parser import ZWaferParser
 
@@ -28,7 +28,7 @@ class FileBrowser(QObject):
         self._refresh_files(show_empty_message=False)
 
     # ===== Exposed Properties =====
-    @Property("QVariantList", notify=filesChanged)
+    @Property("QVariantList", notify=filesChanged)  # type: ignore[arg-type]
     def files(self) -> list[dict[str, object]]:
         return [dict(row) for row in self._files]
 
@@ -37,12 +37,22 @@ class FileBrowser(QObject):
         return str(self._current_directory)
 
     # ===== Directory Selection =====
+    @Slot(str)
+    def setCurrentDirectory(self, path: str) -> None:
+        """Point the browser at `path` without opening a native dialog.
+
+        Used to keep this directory in sync with DeviceController.saveDataDir
+        when the user picks a save folder elsewhere in the app.
+        """
+        self._set_current_directory(Path(path))
+        self._refresh_files(show_empty_message=False)
+
     @Slot()
     def chooseDirectory(self) -> None:
         selected_dir = QFileDialog.getExistingDirectory(
             None,
             "Select CSV Folder",
-            self.currentDirectory,
+            str(self._current_directory),
         )
         if not selected_dir:
             return
@@ -71,17 +81,16 @@ class FileBrowser(QObject):
             self._show_error(f"CSV file was not found:\n{file_path}")
             return
 
+        # ponytail: row is absent when saving metadata for a CSV just read from
+        # the wafer (not in the browser listing) — still write the sidecar.
         row = self._find_row(file_path)
-        if row is None:
-            self._show_error("The selected CSV row is no longer available.")
-            return
-
-        row["wafer"] = wafer
-        row["date"] = date
-        row["chamber"] = chamber
-        row["notes"] = notes
-        row["selected"] = selected
-        row["masterType"] = master_type
+        if row is not None:
+            row["wafer"] = wafer
+            row["date"] = date
+            row["chamber"] = chamber
+            row["notes"] = notes
+            row["selected"] = selected
+            row["masterType"] = master_type
 
         payload = {
             "wafer": wafer,
@@ -119,6 +128,11 @@ class FileBrowser(QObject):
             return
 
         for csv_path in sorted(self._current_directory.glob("*.csv")):
+            # Recorded-live CSVs are named "live_<serial>_<timestamp>.csv" by
+            # SessionController.startRecording (see WaferMapTab's Record button),
+            # distinct from the "<serial>-<timestamp>.csv" convention used by
+            # DeviceController.parseAndSaveData for read-memory dumps.
+            is_recording = csv_path.stem.lower().startswith("live_")
             try:
                 metadata = self._load_metadata(csv_path)
                 wafer_type = metadata.get_wafer_type().upper() or (csv_path.stem[0].upper() if csv_path.stem else "")
@@ -146,6 +160,7 @@ class FileBrowser(QObject):
                         "masterType": master_state.get(str(csv_path), "") or metadata.master_type,
                         "fileName": str(csv_path),
                         "highlight": wafer_type in {"A", "B", "C"},
+                        "isRecording": is_recording,
                     }
                 )
             except Exception:
@@ -169,6 +184,7 @@ class FileBrowser(QObject):
                         "masterType": master_state.get(str(csv_path), ""),
                         "fileName": str(csv_path),
                         "highlight": False,
+                        "isRecording": is_recording,
                     }
                 )
 
@@ -229,11 +245,7 @@ class FileBrowser(QObject):
 
     # ===== Internal Helpers =====
     def _resolve_default_directory(self) -> Path:
-        documents_dir = QStandardPaths.writableLocation(
-            QStandardPaths.DocumentsLocation
-        )
-        base_dir = Path(documents_dir) if documents_dir else (Path.home() / "Documents")
-        return base_dir / DEFAULT_DATA_DIR_NAME
+        return default_data_dir()
 
     def _set_current_directory(self, directory: Path) -> None:
         normalized = Path(directory)

src/pygui/backend/data/local_settings.py

@@ -13,8 +13,8 @@ class LocalSettings:
         # Configuration settings
         self.chamber_id = ""
         self.reverse_z_wafer = False
-        self.master = {}  # Dict[str, str]
-        self.wafer_data_size = {}  # Dict[str, int]
+        self.master: dict[str, str] = {}
+        self.wafer_data_size: dict[str, int] = {}
         self.debug = False
         self.wafer_read_retries = 8
         # Timeout in msec for reading from the wafer (default 2 min)
@@ -32,9 +32,6 @@ class LocalSettings:
         self.data_col_count = 0
         self.last_csv_path = ""
 
-        # Session persistence
-        self.session_last_file = ""
-
     # ===== File Path Helpers =====
     @classmethod
     def _settings_path(cls, directory: str) -> Path:

src/pygui/backend/data/local_settings_model.py

@@ -2,17 +2,26 @@ from __future__ import annotations
 
 from copy import deepcopy
 from pathlib import Path
-from typing import Any
+from typing import Any, Callable
 
-from PySide6.QtCore import Property, QDateTime, QObject, QStandardPaths, Signal, Slot
+from PySide6.QtCore import Property, QDateTime, QObject, Signal, Slot
 
-from pygui.backend.data.constants import DEFAULT_DATA_DIR_NAME
 from pygui.backend.data.local_settings import LocalSettings
 
 MASTER_FAMILIES = ("A", "B", "C", "D", "E", "F", "P", "X", "Z")
 
 
 class LocalSettingsModel(QObject):
+    # Draft attrs are seeded via setattr() in __init__ from _new_defaults();
+    # declared here so mypy knows their types.
+    _chamber_id: str
+    _reverse_z_wafer: bool
+    _debug_mode: bool
+    _wafer_read_timeout: int
+    _wafer_detect_timeout: int
+    _wafer_retries: int
+    _masters: dict[str, str]
+
     chamberIdChanged = Signal()
     reverseZWaferChanged = Signal()
     debugModeChanged = Signal()
@@ -26,18 +35,35 @@ class LocalSettingsModel(QObject):
     saveStatusChanged = Signal()
     lastSavedAtChanged = Signal()
 
-    def __init__(self, parent: QObject | None = None) -> None:
+    # Draft attr (this class) <-> LocalSettings attr (the shared, persisted
+    # instance also held by DeviceController) <-> coercer applied on both
+    # load and revert/reset. One table drives load/save/revert/reset instead
+    # of four hand-written field-by-field copies.
+    _FIELD_MAP: tuple[tuple[str, str, Callable[[Any], Any]], ...] = (
+        ("_chamber_id", "chamber_id", str),
+        ("_reverse_z_wafer", "reverse_z_wafer", bool),
+        ("_debug_mode", "debug", bool),
+        ("_wafer_read_timeout", "wafer_read_timeout", int),
+        ("_wafer_detect_timeout", "wafer_detect_timeout", int),
+        ("_wafer_retries", "wafer_read_retries", int),
+    )
+
+    def __init__(
+        self,
+        settings: LocalSettings,
+        data_dir: Path | str,
+        parent: QObject | None = None,
+    ) -> None:
         super().__init__(parent)
-        self._data_dir = self._resolve_data_dir()
+        # Shared with DeviceController — saving here must mutate this same
+        # instance, not a throwaway copy, or the device layer keeps using
+        # stale config until restart.
+        self._settings = settings
+        self._data_dir = Path(data_dir)
         self._defaults = self._new_defaults()
 
-        self._chamber_id = self._defaults["chamberId"]
-        self._reverse_z_wafer = self._defaults["reverseZWafer"]
-        self._debug_mode = self._defaults["debugMode"]
-        self._wafer_read_timeout = self._defaults["waferReadTimeout"]
-        self._wafer_detect_timeout = self._defaults["waferDetectTimeout"]
-        self._wafer_retries = self._defaults["waferRetries"]
-        self._masters = deepcopy(self._defaults["masters"])
+        for draft_attr, default_value in self._defaults.items():
+            setattr(self, draft_attr, deepcopy(default_value))
 
         self._is_dirty = False
         self._is_valid = True
@@ -47,34 +73,21 @@ class LocalSettingsModel(QObject):
         self._saved_snapshot = self._snapshot()
         self._recompute_derived()
 
-    def _resolve_data_dir(self) -> Path:
-        documents_dir = QStandardPaths.writableLocation(
-            QStandardPaths.DocumentsLocation
-        )
-        base_dir = Path(documents_dir) if documents_dir else (Path.home() / "Documents")
-        return base_dir / DEFAULT_DATA_DIR_NAME
-
     def _new_defaults(self) -> dict[str, Any]:
         return {
-            "chamberId": "2",
-            "reverseZWafer": False,
-            "debugMode": False,
-            "waferReadTimeout": 120000,
-            "waferDetectTimeout": 5000,
-            "waferRetries": 8,
-            "masters": {family: "" for family in MASTER_FAMILIES},
+            "_chamber_id": "2",
+            "_reverse_z_wafer": False,
+            "_debug_mode": False,
+            "_wafer_read_timeout": 120000,
+            "_wafer_detect_timeout": 5000,
+            "_wafer_retries": 8,
+            "_masters": {family: "" for family in MASTER_FAMILIES},
         }
 
     def _snapshot(self) -> dict[str, Any]:
-        return {
-            "chamberId": self._chamber_id,
-            "reverseZWafer": self._reverse_z_wafer,
-            "debugMode": self._debug_mode,
-            "waferReadTimeout": self._wafer_read_timeout,
-            "waferDetectTimeout": self._wafer_detect_timeout,
-            "waferRetries": self._wafer_retries,
-            "masters": deepcopy(self._masters),
-        }
+        snap = {attr: getattr(self, attr) for attr, _, _ in self._FIELD_MAP}
+        snap["_masters"] = deepcopy(self._masters)
+        return snap
 
     def _set_is_dirty(self, value: bool) -> None:
         if self._is_dirty != value:
@@ -137,22 +150,19 @@ class LocalSettingsModel(QObject):
         self.waferRetriesChanged.emit()
         self.mastersChanged.emit()
 
-    def _to_local_settings(self) -> LocalSettings:
-        settings = LocalSettings()
-        settings.chamber_id = self._chamber_id
-        settings.reverse_z_wafer = self._reverse_z_wafer
-        settings.debug = self._debug_mode
-        settings.wafer_read_timeout = self._wafer_read_timeout
-        settings.wafer_detect_timeout = self._wafer_detect_timeout
-        settings.wafer_read_retries = self._wafer_retries
-        settings.master = deepcopy(self._masters)
-        return settings
+    def _normalized_masters(self, source: dict[str, str]) -> dict[str, str]:
+        masters = {family: "" for family in MASTER_FAMILIES}
+        for family, value in source.items():
+            normalized = str(family).strip().upper()
+            if normalized in masters:
+                masters[normalized] = str(value).strip()
+        return masters
 
     @Property(str, notify=chamberIdChanged)
     def chamberId(self) -> str:
         return self._chamber_id
 
-    @chamberId.setter
+    @chamberId.setter  # type: ignore[no-redef]
     def chamberId(self, value: str) -> None:
         next_value = str(value).strip()
         if self._chamber_id == next_value:
@@ -165,7 +175,7 @@ class LocalSettingsModel(QObject):
     def reverseZWafer(self) -> bool:
         return self._reverse_z_wafer
 
-    @reverseZWafer.setter
+    @reverseZWafer.setter  # type: ignore[no-redef]
     def reverseZWafer(self, value: bool) -> None:
         if self._reverse_z_wafer == value:
             return
@@ -177,7 +187,7 @@ class LocalSettingsModel(QObject):
     def debugMode(self) -> bool:
         return self._debug_mode
 
-    @debugMode.setter
+    @debugMode.setter  # type: ignore[no-redef]
     def debugMode(self, value: bool) -> None:
         if self._debug_mode == value:
             return
@@ -189,7 +199,7 @@ class LocalSettingsModel(QObject):
     def waferReadTimeout(self) -> int:
         return self._wafer_read_timeout
 
-    @waferReadTimeout.setter
+    @waferReadTimeout.setter  # type: ignore[no-redef]
     def waferReadTimeout(self, value: int) -> None:
         if self._wafer_read_timeout == value:
             return
@@ -201,7 +211,7 @@ class LocalSettingsModel(QObject):
     def waferDetectTimeout(self) -> int:
         return self._wafer_detect_timeout
 
-    @waferDetectTimeout.setter
+    @waferDetectTimeout.setter  # type: ignore[no-redef]
     def waferDetectTimeout(self, value: int) -> None:
         if self._wafer_detect_timeout == value:
             return
@@ -213,7 +223,7 @@ class LocalSettingsModel(QObject):
     def waferRetries(self) -> int:
         return self._wafer_retries
 
-    @waferRetries.setter
+    @waferRetries.setter  # type: ignore[no-redef]
     def waferRetries(self, value: int) -> None:
         if self._wafer_retries == value:
             return
@@ -251,22 +261,11 @@ class LocalSettingsModel(QObject):
 
     @Slot()
     def loadSettings(self) -> None:
-        loaded = LocalSettings.read_settings(str(self._data_dir))
-        self._chamber_id = str(loaded.chamber_id).strip() or str(
-            self._defaults["chamberId"]
-        )
-        self._reverse_z_wafer = bool(loaded.reverse_z_wafer)
-        self._debug_mode = bool(loaded.debug)
-        self._wafer_read_timeout = int(loaded.wafer_read_timeout)
-        self._wafer_detect_timeout = int(loaded.wafer_detect_timeout)
-        self._wafer_retries = int(loaded.wafer_read_retries)
-
-        masters = {family: "" for family in MASTER_FAMILIES}
-        for family, value in loaded.master.items():
-            normalized = str(family).strip().upper()
-            if normalized in masters:
-                masters[normalized] = str(value).strip()
-        self._masters = masters
+        """Seed draft fields from the shared LocalSettings instance."""
+        for draft_attr, settings_attr, coerce in self._FIELD_MAP:
+            setattr(self, draft_attr, coerce(getattr(self._settings, settings_attr)))
+        self._chamber_id = self._chamber_id.strip() or str(self._defaults["_chamber_id"])
+        self._masters = self._normalized_masters(self._settings.master)
 
         self._saved_snapshot = self._snapshot()
         self._emit_all_changed()
@@ -275,13 +274,18 @@ class LocalSettingsModel(QObject):
 
     @Slot()
     def saveSettings(self) -> None:
+        """Write draft fields onto the shared LocalSettings instance and persist it."""
         self._recompute_derived()
         if not self._is_valid:
             self._set_save_status("error: invalid settings")
             return
 
         try:
-            LocalSettings.save_settings(str(self._data_dir), self._to_local_settings())
+            for draft_attr, settings_attr, _coerce in self._FIELD_MAP:
+                setattr(self._settings, settings_attr, getattr(self, draft_attr))
+            self._settings.master = deepcopy(self._masters)
+            LocalSettings.save_settings(str(self._data_dir), self._settings)
+
             self._saved_snapshot = self._snapshot()
             self._recompute_derived()
             self._set_save_status("Saved")
@@ -293,13 +297,9 @@ class LocalSettingsModel(QObject):
     @Slot()
     def revertChanges(self) -> None:
         snap = self._saved_snapshot
-        self._chamber_id = str(snap["chamberId"])
-        self._reverse_z_wafer = bool(snap["reverseZWafer"])
-        self._debug_mode = bool(snap["debugMode"])
-        self._wafer_read_timeout = int(snap["waferReadTimeout"])
-        self._wafer_detect_timeout = int(snap["waferDetectTimeout"])
-        self._wafer_retries = int(snap["waferRetries"])
-        self._masters = deepcopy(snap["masters"])
+        for draft_attr, _settings_attr, coerce in self._FIELD_MAP:
+            setattr(self, draft_attr, coerce(snap[draft_attr]))
+        self._masters = deepcopy(snap["_masters"])
 
         self._emit_all_changed()
         self._recompute_derived()
@@ -307,13 +307,9 @@ class LocalSettingsModel(QObject):
 
     @Slot()
     def resetDefaults(self) -> None:
-        self._chamber_id = str(self._defaults["chamberId"])
-        self._reverse_z_wafer = bool(self._defaults["reverseZWafer"])
-        self._debug_mode = bool(self._defaults["debugMode"])
-        self._wafer_read_timeout = int(self._defaults["waferReadTimeout"])
-        self._wafer_detect_timeout = int(self._defaults["waferDetectTimeout"])
-        self._wafer_retries = int(self._defaults["waferRetries"])
-        self._masters = deepcopy(self._defaults["masters"])
+        for draft_attr, _settings_attr, coerce in self._FIELD_MAP:
+            setattr(self, draft_attr, coerce(self._defaults[draft_attr]))
+        self._masters = deepcopy(self._defaults["_masters"])
 
         self._emit_all_changed()
         self._recompute_derived()

src/pygui/backend/license/license_manager.py

@@ -0,0 +1,126 @@
+"""C#-compatible wafer license file parsing.
+
+License files are AES-128-CBC encrypted `.bin` blobs named
+``X00000-00.bin`` where ``X`` is the wafer family code, ``00000`` the
+5-digit serial number, and ``00`` the 2-digit license level. The blob is
+``ciphertext || iv`` (IV is the trailing 16 bytes). The decrypted text is
+a fixed-offset record::
+
+    [0:6]   serial       e.g. "A00001"
+    [7:15]  mfg date     8 hex chars
+    [16:18] level        2 decimal digits ("00" basic, "01"+ adds replay)
+    [19:27] license date 8 hex chars
+
+The key is hardcoded to match the C# application exactly
+"""
+
+import logging
+import re
+from dataclasses import dataclass
+from pathlib import Path
+
+from pygui.backend.crypto.crypto_helper import CryptoHelper
+
+log = logging.getLogger(__name__)
+
+LICENSE_KEY = b"ThisIsA16ByteKey"
+LICENSE_FILENAME_RE = re.compile(r"^[A-Z]\d{5}-\d{2}\.bin$")
+
+_MIN_TEXT_LEN = 27
+
+
+# ===== License Record =====
+@dataclass(frozen=True)
+class License:
+    """One parsed license file (all fields as stored in the file)."""
+
+    serial: str        # "A00001"
+    level: str         # "00".."03"
+    mfg_date_hex: str  # 8 hex chars
+    lic_date_hex: str  # 8 hex chars
+
+    @property
+    def level_int(self) -> int:
+        """Level as int; -1 if unparseable."""
+        try:
+            return int(self.level, 10)
+        except ValueError:
+            return -1
+
+    @property
+    def mfg_date_decimal(self) -> str:
+        """Mfg date shown as decimal (C# grid does Convert.ToInt64(hex, 16))."""
+        return _hex_to_decimal(self.mfg_date_hex)
+
+    @property
+    def lic_date_decimal(self) -> str:
+        """License date shown as decimal, same conversion as the C# grid."""
+        return _hex_to_decimal(self.lic_date_hex)
+
+
+def _hex_to_decimal(hex_str: str) -> str:
+    try:
+        return str(int(hex_str, 16))
+    except ValueError:
+        return ""
+
+
+# ===== Blob Parsing =====
+def split_data_iv(blob: bytes) -> tuple[bytes, bytes]:
+    """Split a license blob into (ciphertext, iv) — IV is the last 16 bytes."""
+    if len(blob) < 32:
+        raise ValueError("License blob too short")
+    return blob[:-16], blob[-16:]
+
+
+def parse_license_blob(blob: bytes) -> License | None:
+    """Decrypt and parse one license blob. None if malformed."""
+    try:
+        data, iv = split_data_iv(blob)
+        message = CryptoHelper.decrypt_aes(data, LICENSE_KEY, iv)
+        text = message.decode("utf-8")
+    except (ValueError, UnicodeDecodeError) as exc:
+        log.warning("Undecryptable license blob: %s", exc)
+        return None
+
+    if len(text) < _MIN_TEXT_LEN:
+        log.warning("License text too short (%d chars)", len(text))
+        return None
+
+    return License(
+        serial=text[0:6],
+        mfg_date_hex=text[7:15],
+        level=text[16:18],
+        lic_date_hex=text[19:27],
+    )
+
+
+# ===== Directory Scan =====
+def read_license_files(licenses_dir: str | Path) -> list[License]:
+    """Parse every valid license .bin in the directory.
+
+    A file counts only if its name matches ``X00000-00.bin`` AND equals
+    ``{serial}-{level}.bin`` from its own decrypted payload — same
+    tamper check as the C# app.
+    """
+    directory = Path(licenses_dir)
+    if not directory.is_dir():
+        return []
+
+    licenses: list[License] = []
+    for path in sorted(directory.glob("*.bin")):
+        if not LICENSE_FILENAME_RE.match(path.name):
+            continue
+        try:
+            blob = path.read_bytes()
+        except OSError as exc:
+            log.warning("Cannot read license file %s: %s", path, exc)
+            continue
+        lic = parse_license_blob(blob)
+        if lic is None:
+            continue
+        if path.name != f"{lic.serial}-{lic.level}.bin":
+            log.warning("License filename mismatch: %s", path.name)
+            continue
+        licenses.append(lic)
+    return licenses

src/pygui/backend/license/license_model.py

@@ -0,0 +1,146 @@
+"""QML-facing license model: grid rows, Load License, replay trial marker."""
+
+import logging
+import shutil
+import time
+from pathlib import Path
+from urllib.parse import unquote, urlparse
+
+from PySide6.QtCore import Property, QObject, Signal, Slot
+
+from pygui.backend.license.license_manager import (
+    LICENSE_FILENAME_RE,
+    License,
+    parse_license_blob,
+    read_license_files,
+)
+
+log = logging.getLogger(__name__)
+
+TRIAL_DAYS = 30
+
+
+def _to_local_path(path_or_url: str) -> Path:
+    """Accept both plain paths and file:// URLs (QML FileDialog gives URLs)."""
+    if path_or_url.startswith("file:"):
+        return Path(unquote(urlparse(path_or_url).path))
+    return Path(path_or_url)
+
+
+# ===== License Model =====
+class LicenseModel(QObject):
+    """Context property backing the About dialog license grid.
+
+    Licenses live in ``<data_dir>/licenses`` (mirrors C#'s
+    ``DataDir\\licenses``). The 30-day replay trial marker is
+    ``<data_dir>/replay.lic``.
+    """
+
+    licensesChanged = Signal()
+
+    def __init__(self, data_dir: str, parent: QObject | None = None) -> None:
+        super().__init__(parent)
+        self._data_dir = Path(data_dir)
+        self._licenses_dir = self._data_dir / "licenses"
+        try:
+            self._licenses_dir.mkdir(parents=True, exist_ok=True)
+        except OSError as exc:
+            log.warning("Cannot create licenses dir %s: %s", self._licenses_dir, exc)
+        self._licenses: list[License] = []
+        self.refresh()
+
+    # ── Grid rows ─────────────────────────────────────────────────────
+    @Property("QVariantList", notify=licensesChanged)  # type: ignore[arg-type]
+    def licenses(self) -> list:
+        """Rows for the About grid: serial, mfg date, level, license date."""
+        return [
+            {
+                "serial": lic.serial,
+                "mfgDate": lic.mfg_date_decimal,
+                "level": lic.level,
+                "licDate": lic.lic_date_decimal,
+            }
+            for lic in self._licenses
+        ]
+
+    @Slot()
+    def refresh(self) -> None:
+        """Re-scan the licenses directory."""
+        self._licenses = read_license_files(self._licenses_dir)
+        self.licensesChanged.emit()
+
+    # ── Load License ──────────────────────────────────────────────────
+    @Slot(str, result=bool)
+    def loadLicenseFile(self, path_or_url: str) -> bool:
+        """Validate a picked .bin and copy it into the licenses directory."""
+        src = _to_local_path(path_or_url)
+        if not src.is_file():
+            log.warning("License file does not exist: %s", src)
+            return False
+        if not LICENSE_FILENAME_RE.match(src.name):
+            log.warning("License filename invalid: %s", src.name)
+            return False
+
+        try:
+            blob = src.read_bytes()
+        except OSError as exc:
+            log.warning("Cannot read license file %s: %s", src, exc)
+            return False
+
+        lic = parse_license_blob(blob)
+        if lic is None or src.name != f"{lic.serial}-{lic.level}.bin":
+            log.warning("License file failed validation: %s", src.name)
+            return False
+
+        try:
+            self._licenses_dir.mkdir(parents=True, exist_ok=True)
+            shutil.copyfile(src, self._licenses_dir / src.name)
+        except OSError as exc:
+            log.warning("Cannot copy license into %s: %s", self._licenses_dir, exc)
+            return False
+
+        self.refresh()
+        return True
+
+    # ── Wafer detect (informational) ──────────────────────────────────
+    @Slot(str, result=str)
+    def levelForWafer(self, serial: str) -> str:
+        """License level for a wafer serial like "A00001"; "" if unlicensed."""
+        for lic in self._licenses:
+            if lic.serial == serial:
+                return lic.level
+        return ""
+
+    # ── Replay trial (30-day marker, C# parity) ───────────────────────
+    @property
+    def _trial_marker(self) -> Path:
+        return self._data_dir / "replay.lic"
+
+    @Slot(result=str)
+    def replayLicenseState(self) -> str:
+        """"permanent" if any license level >= 1, "temporary" if trial
+        marker exists, else "none" (trial not started)."""
+        if any(lic.level_int >= 1 for lic in self._licenses):
+            return "permanent"
+        if self._trial_marker.exists():
+            return "temporary"
+        return "none"
+
+    @Slot(result=bool)
+    def startReplayTrial(self) -> bool:
+        """Create the trial marker (idempotent). False on I/O failure."""
+        try:
+            self._trial_marker.touch(exist_ok=True)
+            return True
+        except OSError as exc:
+            log.warning("Cannot create trial marker: %s", exc)
+            return False
+
+    @Slot(result=bool)
+    def replayTrialExpired(self) -> bool:
+        """True once the marker is older than 30 days (or missing)."""
+        marker = self._trial_marker
+        if not marker.exists():
+            return True
+        age_days = (time.time() - marker.stat().st_mtime) / 86400.0
+        return age_days > TRIAL_DAYS

src/pygui/backend/models/__init__.py

@@ -1,19 +0,0 @@
-# ===== Models Sub-package =====
-from pygui.backend.models.data_model import TemperatureTableModel
-from pygui.backend.models.frame import Frame
-from pygui.backend.models.frame_player import FramePlayer, frames_from_wafer_data
-from pygui.backend.models.frame_stats import Stats, compute_stats
-from pygui.backend.models.sensor_editor import SensorEditor
-from pygui.backend.models.session_model import SessionModel, SessionUpdate
-from pygui.backend.models.stability_detector import StabilityDetector
-from pygui.backend.models.threshold_classifier import ThresholdConfig, classify, resolve_bounds
-
-__all__ = [
-    "Frame", "FramePlayer", "frames_from_wafer_data",
-    "Stats", "compute_stats",
-    "SessionModel", "SessionUpdate",
-    "TemperatureTableModel",
-    "SensorEditor",
-    "ThresholdConfig", "classify", "resolve_bounds",
-    "StabilityDetector",
-]

src/pygui/backend/models/data_model.py

@@ -55,7 +55,7 @@ class TemperatureTableModel(QAbstractTableModel):
         # Column 0 = row index, columns 1..N = sensor values
         return self._col_count + 1
 
-    def data(self, index: Any, role: int = ...) -> Any:
+    def data(self, index: Any, role: int = ...) -> Any:  # type: ignore[assignment]
         if not index.isValid():
             return None
 
@@ -73,7 +73,7 @@ class TemperatureTableModel(QAbstractTableModel):
         return None
 
     def headerData(
-        self, section: int, orientation: int, role: int = ...
+        self, section: int, orientation: Qt.Orientation, role: int = ...  # type: ignore[assignment]
     ) -> Any:
         if role != Qt.ItemDataRole.DisplayRole:
             return None

src/pygui/backend/models/frame_player.py

@@ -4,10 +4,23 @@ from pygui.backend.models.frame import Frame
 from pygui.backend.wafer.zwafer_models import ZWaferData
 
 
-def frames_from_wafer_data(data: ZWaferData, records) -> list[Frame]:
+def frames_from_wafer_data(data: ZWaferData | None, records) -> list[Frame]:
     """Build Frames from parsed DataRecords (records = list[DataRecord].)"""
     return [Frame(seq=i, time=r.time, values=list(r.values)) for i, r in enumerate(records)]
 
+
+def all_sensor_series(frames: list[Frame]) -> tuple[list[str], list[list[float]]]:
+    """Per-sensor value series across every frame, for the whole-run Graph tab.
+
+    Sensor names are 1-based ("Sensor 1", ...), matching the C# original.
+    """
+    if not frames:
+        return [], []
+    n_sensors = len(frames[0].values)
+    names = [f"Sensor {i + 1}" for i in range(n_sensors)]
+    series = [[frame.values[i] for frame in frames] for i in range(n_sensors)]
+    return names, series
+
 class FramePlayer:
     def __init__(self) -> None:
         self._frames: list[Frame] =[]
@@ -22,6 +35,10 @@ class FramePlayer:
     def total(self) -> int:
         return len(self._frames)
 
+    @property
+    def frames(self) -> tuple[Frame, ...]:
+        return tuple(self._frames)
+
     @property
     def index(self) -> int:
         return self._i

src/pygui/backend/models/frame_stats.py

@@ -14,6 +14,44 @@ class Stats:
     sigma: float; three_sigma: float
 
 
+@dataclass(frozen=True)
+class EdgeCenterStats:
+    min_edge_index: int; min_center_index: int
+    min_edge: float; min_center: float; min_delta: float
+    max_edge_index: int; max_center_index: int
+    max_edge: float; max_center: float; max_delta: float
+
+
+def compute_edge_center(
+    values: list[float],
+    pairs: tuple[tuple[int, int], ...],
+    excluded: set[int],
+) -> EdgeCenterStats | None:
+    """Min/max |edge - center| over the family's pair table.
+
+    Pairs with an excluded (replaced) sensor, an index outside the frame, or a
+    NaN value are skipped. Returns None when no pair is computable.
+    """
+    n = len(values)
+    best: list[tuple[float, int, int]] = []
+    for e, c in pairs:
+        if e in excluded or c in excluded or e >= n or c >= n:
+            continue
+        if math.isnan(values[e]) or math.isnan(values[c]):
+            continue
+        best.append((abs(values[e] - values[c]), e, c))
+    if not best:
+        return None
+    min_d, min_e, min_c = min(best)
+    max_d, max_e, max_c = max(best)
+    return EdgeCenterStats(
+        min_edge_index=min_e, min_center_index=min_c,
+        min_edge=values[min_e], min_center=values[min_c], min_delta=min_d,
+        max_edge_index=max_e, max_center_index=max_c,
+        max_edge=values[max_e], max_center=values[max_c], max_delta=max_d,
+    )
+
+
 def compute_stats(values: list[float]) -> Stats:
     clean = [(i, v) for i, v in enumerate(values) if not math.isnan(v)]
     if not clean:

src/pygui/backend/models/sensor_editor.py

@@ -28,6 +28,11 @@ class SensorEditor:
     def has_overrides(self) -> bool:
         return bool(self._replacements or self._offsets)
 
+    def replaced_indices(self) -> set[int]:
+        """Sensors whose value is a replacement (offsets don't count — an
+        offset sensor still reads from its physical location)."""
+        return set(self._replacements)
+
     def active_indices(self) -> list[int]:
         """Return sorted sensor indices that have any override."""
         return sorted(set(self._replacements) | set(self._offsets))

src/pygui/backend/visualization/__init__.py

@@ -1,11 +0,0 @@
-# ===== Visualization Sub-package =====
-from pygui.backend.visualization.graph_quick_item import GraphQuickItem
-from pygui.backend.visualization.graph_view import GraphView
-from pygui.backend.visualization.rbf_heatmap import interpolate_field
-from pygui.backend.visualization.trend_chart_item import TrendChartItem
-from pygui.backend.visualization.wafer_map_item import WaferMapItem
-
-__all__ = [
-    "GraphQuickItem", "GraphView", "TrendChartItem", "WaferMapItem",
-    "interpolate_field",
-]

src/pygui/backend/visualization/chart_geometry.py

@@ -0,0 +1,52 @@
+"""Pure coordinate-mapping math shared by the QQuickPaintedItem chart items
+(GraphQuickItem, TrendChartItem). No QPainter or Qt-widget dependency, so
+it's testable without a GUI — unlike the paint() methods that call it.
+"""
+from __future__ import annotations
+
+
+def value_to_pixel(
+    value: float,
+    value_min: float,
+    value_max: float,
+    pixel_start: float,
+    pixel_span: float,
+) -> float:
+    """Map a value onto a pixel range, inverted so larger values sit at
+    smaller pixel coordinates (screen y grows downward).
+
+    Also used for evenly-spaced tick indices: pass the tick index as
+    `value` and `(tick_count - 1)` as `value_max` with `value_min=0`.
+    """
+    value_range = value_max - value_min
+    if value_range < 1e-9:
+        return pixel_start + pixel_span / 2
+    fraction = 1.0 - (value - value_min) / value_range
+    return pixel_start + fraction * pixel_span
+
+
+def index_to_pixel(index: float, count: int, pixel_start: float, pixel_span: float) -> float:
+    """Map a 0-based sample index onto a pixel range, left to right."""
+    if count <= 1:
+        return pixel_start + pixel_span / 2
+    fraction = index / (count - 1)
+    return pixel_start + fraction * pixel_span
+
+
+def elapsed_to_pixel(
+    elapsed: float,
+    window_start: float,
+    window_end: float,
+    pixel_start: float,
+    pixel_span: float,
+) -> float:
+    """Map an elapsed-seconds value onto a pixel range, left to right.
+
+    Unlike `value_to_pixel`, this is not inverted: larger elapsed values sit
+    at larger pixel x-coordinates, matching how time flows left-to-right.
+    """
+    window_span = window_end - window_start
+    if window_span < 1e-9:
+        return pixel_start + pixel_span
+    fraction = (elapsed - window_start) / window_span
+    return pixel_start + fraction * pixel_span

src/pygui/backend/visualization/graph_quick_item.py

@@ -21,15 +21,60 @@ Usage from QML::
 
 from __future__ import annotations
 
-from PySide6.QtCore import Property, QRectF, Qt, Signal
+import math
+
+from PySide6.QtCore import Property, QRectF, Qt, Signal, Slot
 from PySide6.QtGui import QColor, QFont, QFontMetrics, QPainter, QPen
 from PySide6.QtQml import QmlElement
 from PySide6.QtQuick import QQuickPaintedItem
 
+from pygui.backend.visualization.chart_geometry import index_to_pixel, value_to_pixel
+
 QML_IMPORT_NAME = "ISC.Wafer"
 QML_IMPORT_MAJOR_VERSION = 1
 
 
+def viewport_stats(
+    series: list[list[float]],
+    names: list[str],
+    start: int,
+    end: int,
+) -> tuple[float, float, float, str, str]:
+    """Aggregate min/max/avg across every sensor's points in `[start, end]`.
+
+    Mirrors PopupChartForm.cs's `recalc_stats`: one running min/max/avg over
+    every visible point from every series, plus which sensor achieved each
+    extreme. Non-numeric values are skipped. No points in range -> zeros and
+    empty sensor names.
+    """
+    vmin = math.inf
+    vmax = -math.inf
+    total = 0.0
+    count = 0
+    min_sensor = ""
+    max_sensor = ""
+    for i, s in enumerate(series):
+        name = names[i] if i < len(names) else ""
+        lo = max(0, start)
+        hi = min(len(s) - 1, end)
+        for j in range(lo, hi + 1):
+            try:
+                v = float(s[j])
+            except (TypeError, ValueError):
+                continue
+            if v < vmin:
+                vmin = v
+                min_sensor = name
+            if v > vmax:
+                vmax = v
+                max_sensor = name
+            total += v
+            count += 1
+    if count == 0:
+        return (0.0, 0.0, 0.0, "", "")
+    return (vmin, vmax, total / count, min_sensor, max_sensor)
+
+
 @QmlElement
 class GraphQuickItem(QQuickPaintedItem):
     """Painted line chart; driven by series data passed via QML property bindings."""
@@ -40,6 +85,8 @@ class GraphQuickItem(QQuickPaintedItem):
     xLabelChanged = Signal()
     yLabelChanged = Signal()
     colorsChanged = Signal()
+    viewportChanged = Signal()
+    viewStatsChanged = Signal()
 
     def __init__(self, parent=None) -> None:
         super().__init__(parent)
@@ -72,16 +119,37 @@ class GraphQuickItem(QQuickPaintedItem):
         self._max_y: float = 150.0
         self._padding: dict[str, int] = {"left": 60, "right": 20, "top": 30, "bottom": 50}
 
+        # Viewport (replay chart zoom/pan): defaults reproduce "whole series",
+        # so the Graph tab (which never sets these) is unaffected. See
+        # docs/adr/0004-graphquickitem-viewport-for-replay-chart.md.
+        self._view_start: int = 0
+        self._view_end: int = -1
+        self._show_min_max_markers: bool = False
+        self._view_min: float = 0.0
+        self._view_max: float = 0.0
+        self._view_avg: float = 0.0
+        self._view_min_sensor: str = ""
+        self._view_max_sensor: str = ""
+
     # ── Qt properties (QML-bindable) ──────────────────────────────────────────
 
     @Property("QVariantList", notify=seriesDataChanged)
     def seriesData(self) -> list:
         return self._series_data
 
-    @seriesData.setter
+    @seriesData.setter  # type: ignore[no-redef]
     def seriesData(self, val: list) -> None:
         self._series_data = [list(s) for s in (val or [])]
+        # New data resets the viewport to the full range -- matches
+        # PopupChartForm.cs's SetData(), which resets AxisX.Minimum/Maximum
+        # before RecalculateAxesScale(). Without this, a stale viewport left
+        # over from a previous (longer) series can point entirely past the
+        # new data -- every per-series slice becomes empty and the chart
+        # silently renders nothing instead of the new data.
+        self._view_start = 0
+        self._view_end = -1
         self._auto_range()
+        self._recompute_view_stats()
         self.seriesDataChanged.emit()
         self.update()
 
@@ -89,17 +157,138 @@ class GraphQuickItem(QQuickPaintedItem):
     def sensorNames(self) -> list:
         return self._sensor_names
 
-    @sensorNames.setter
+    @sensorNames.setter  # type: ignore[no-redef]
     def sensorNames(self, val: list) -> None:
         self._sensor_names = list(val or [])
+        self._recompute_view_stats()
         self.sensorNamesChanged.emit()
         self.update()
 
+    # ── Viewport properties (replay chart zoom/pan) ────────────────────────
+
+    @Property(int, notify=viewportChanged)
+    def viewStartIndex(self) -> int:
+        return self._view_start
+
+    @viewStartIndex.setter  # type: ignore[no-redef]
+    def viewStartIndex(self, val: int) -> None:
+        v = max(0, int(val))
+        if v == self._view_start:
+            return
+        self._view_start = v
+        self._on_viewport_changed()
+
+    @Property(int, notify=viewportChanged)
+    def viewEndIndex(self) -> int:
+        return self._view_end
+
+    @viewEndIndex.setter  # type: ignore[no-redef]
+    def viewEndIndex(self, val: int) -> None:
+        v = int(val)
+        if v == self._view_end:
+            return
+        self._view_end = v
+        self._on_viewport_changed()
+
+    @Property(bool, notify=viewportChanged)
+    def showMinMaxMarkers(self) -> bool:
+        return self._show_min_max_markers
+
+    @showMinMaxMarkers.setter  # type: ignore[no-redef]
+    def showMinMaxMarkers(self, val: bool) -> None:
+        v = bool(val)
+        if v == self._show_min_max_markers:
+            return
+        self._show_min_max_markers = v
+        self.viewportChanged.emit()
+        self.update()
+
+    @Property(float, notify=viewStatsChanged)
+    def viewMin(self) -> float:
+        return self._view_min
+
+    @Property(float, notify=viewStatsChanged)
+    def viewMax(self) -> float:
+        return self._view_max
+
+    @Property(float, notify=viewStatsChanged)
+    def viewAvg(self) -> float:
+        return self._view_avg
+
+    @Property(str, notify=viewStatsChanged)
+    def viewMinSensor(self) -> str:
+        return self._view_min_sensor
+
+    @Property(str, notify=viewStatsChanged)
+    def viewMaxSensor(self) -> str:
+        return self._view_max_sensor
+
+    # ── Zoom/pan slots (replay chart interaction; QML MouseArea calls these
+    #    with fractions derived from wheel/drag pixel deltas) ───────────────
+
+    @Slot(float, float)
+    def zoomAtFraction(self, frac: float, factor: float) -> None:
+        """Zoom the viewport around a fractional X position within it.
+
+        `frac` in [0, 1] is where within the current viewport to zoom around;
+        `factor < 1` narrows the window (zoom in), `factor > 1` widens it
+        (zoom out). Clamped to data bounds and a minimum 1-index window.
+        """
+        max_len = max((len(s) for s in self._series_data), default=0)
+        if max_len < 2:
+            return
+        start = float(self._view_start)
+        end = float(self._resolved_view_end())
+        width = max(1.0, end - start)
+        f = max(0.0, min(1.0, frac))
+        center = start + f * width
+        new_width = max(1.0, min(float(max_len - 1), width * max(0.01, factor)))
+        new_start = center - f * new_width
+        new_end = new_start + new_width
+        self._set_viewport_clamped(new_start, new_end, max_len)
+
+    @Slot(float)
+    def panByFraction(self, delta_frac: float) -> None:
+        """Shift the viewport by `delta_frac * window_width` indices."""
+        max_len = max((len(s) for s in self._series_data), default=0)
+        if max_len < 2:
+            return
+        start = float(self._view_start)
+        end = float(self._resolved_view_end())
+        width = max(1.0, end - start)
+        shift = delta_frac * width
+        self._set_viewport_clamped(start + shift, end + shift, max_len)
+
+    @Slot()
+    def resetZoom(self) -> None:
+        """Restore the full-range viewport sentinel (0, -1)."""
+        self._set_viewport(0, -1)
+
+    def _set_viewport_clamped(self, new_start: float, new_end: float, max_len: int) -> None:
+        if new_start < 0.0:
+            new_end -= new_start
+            new_start = 0.0
+        if new_end > max_len - 1:
+            new_start -= new_end - (max_len - 1)
+            new_end = float(max_len - 1)
+        new_start = max(0.0, new_start)
+        self._set_viewport(int(round(new_start)), int(round(new_end)))
+
+    def _set_viewport(self, start: int, end: int) -> None:
+        """Set the viewport bounds directly (not through the QML-facing
+        property setters, so this stays a plain attribute write for mypy)."""
+        new_start = max(0, start)
+        if new_start == self._view_start and end == self._view_end:
+            return
+        self._view_start = new_start
+        self._view_end = end
+        self._on_viewport_changed()
+
     @Property(str, notify=titleChanged)
     def title(self) -> str:
         return self._title
 
-    @title.setter
+    @title.setter  # type: ignore[no-redef]
     def title(self, val: str) -> None:
         self._title = str(val or "")
         self.titleChanged.emit()
@@ -109,7 +298,7 @@ class GraphQuickItem(QQuickPaintedItem):
     def xLabel(self) -> str:
         return self._x_label
 
-    @xLabel.setter
+    @xLabel.setter  # type: ignore[no-redef]
     def xLabel(self, val: str) -> None:
         self._x_label = str(val or "")
         self.xLabelChanged.emit()
@@ -119,7 +308,7 @@ class GraphQuickItem(QQuickPaintedItem):
     def yLabel(self) -> str:
         return self._y_label
 
-    @yLabel.setter
+    @yLabel.setter  # type: ignore[no-redef]
     def yLabel(self, val: str) -> None:
         self._y_label = str(val or "")
         self.yLabelChanged.emit()
@@ -129,7 +318,7 @@ class GraphQuickItem(QQuickPaintedItem):
     def showLegend(self) -> bool:
         return self._show_legend
 
-    @showLegend.setter
+    @showLegend.setter  # type: ignore[no-redef]
     def showLegend(self, val: bool) -> None:
         self._show_legend = bool(val)
         self.colorsChanged.emit()
@@ -141,7 +330,7 @@ class GraphQuickItem(QQuickPaintedItem):
     def backgroundColor(self) -> QColor:
         return self._bg_color
 
-    @backgroundColor.setter
+    @backgroundColor.setter  # type: ignore[no-redef]
     def backgroundColor(self, c: QColor) -> None:
         self._bg_color = c
         self.update()
@@ -150,7 +339,7 @@ class GraphQuickItem(QQuickPaintedItem):
     def gridColor(self) -> QColor:
         return self._grid_color
 
-    @gridColor.setter
+    @gridColor.setter  # type: ignore[no-redef]
     def gridColor(self, c: QColor) -> None:
         self._grid_color = c
         self.update()
@@ -159,7 +348,7 @@ class GraphQuickItem(QQuickPaintedItem):
     def axisColor(self) -> QColor:
         return self._axis_color
 
-    @axisColor.setter
+    @axisColor.setter  # type: ignore[no-redef]
     def axisColor(self, c: QColor) -> None:
         self._axis_color = c
         self.update()
@@ -168,7 +357,7 @@ class GraphQuickItem(QQuickPaintedItem):
     def textColor(self) -> QColor:
         return self._text_color
 
-    @textColor.setter
+    @textColor.setter  # type: ignore[no-redef]
     def textColor(self, c: QColor) -> None:
         self._text_color = c
         self.update()
@@ -178,7 +367,7 @@ class GraphQuickItem(QQuickPaintedItem):
         """Return hex strings of the current series color palette."""
         return [c.name() for c in self._series_colors]
 
-    @seriesColors.setter
+    @seriesColors.setter  # type: ignore[no-redef]
     def seriesColors(self, hex_list: list) -> None:
         colors = []
         for h in (hex_list or []):
@@ -192,13 +381,38 @@ class GraphQuickItem(QQuickPaintedItem):
 
     # ── internal ──────────────────────────────────────────────────────────────
 
+    def _resolved_view_end(self) -> int:
+        """`viewEndIndex` with the -1 ("last index") sentinel resolved."""
+        max_len = max((len(s) for s in self._series_data), default=0)
+        if self._view_end < 0 or self._view_end > max_len - 1:
+            return max_len - 1
+        return self._view_end
+
+    def _on_viewport_changed(self) -> None:
+        self._auto_range()
+        self._recompute_view_stats()
+        self.viewportChanged.emit()
+        self.update()
+
+    def _recompute_view_stats(self) -> None:
+        end = self._resolved_view_end()
+        vmin, vmax, avg, min_sensor, max_sensor = viewport_stats(
+            self._series_data, self._sensor_names, self._view_start, end
+        )
+        self._view_min, self._view_max, self._view_avg = vmin, vmax, avg
+        self._view_min_sensor, self._view_max_sensor = min_sensor, max_sensor
+        self.viewStatsChanged.emit()
+
     def _auto_range(self) -> None:
-        """Set Y range to cover all data with 10% padding."""
+        """Set Y range to cover the current viewport's data with 10% padding."""
+        start = max(0, self._view_start)
+        end = self._resolved_view_end()
         all_vals: list[float] = []
         for series in self._series_data:
-            for v in series:
+            hi = min(len(series) - 1, end)
+            for i in range(start, hi + 1):
                 try:
-                    all_vals.append(float(v))
+                    all_vals.append(float(series[i]))
                 except (ValueError, TypeError):
                     pass
         if not all_vals:
@@ -275,8 +489,7 @@ class GraphQuickItem(QQuickPaintedItem):
 
         for i in range(n_y_ticks):
             y_val = self._min_y + i * y_step
-            y_frac = 1.0 - (i / (n_y_ticks - 1)) if n_y_ticks > 1 else 0.5
-            y_px = plot_top + y_frac * plot_h
+            y_px = value_to_pixel(i, 0, n_y_ticks - 1, plot_top, plot_h)
 
             # Grid line
             painter.setPen(grid_pen)
@@ -318,19 +531,23 @@ class GraphQuickItem(QQuickPaintedItem):
                 self._x_label,
             )
 
-        # --- X-axis ticks ---
-        num_points = max(len(s) for s in self._series_data) if self._series_data else 0
-        if num_points > 1:
-            n_x_ticks = min(num_points, max(2, int(plot_w // 80)))
-            x_tick_step = (num_points - 1) / max(1, n_x_ticks - 1)
+        # --- Viewport slice (replay chart zoom/pan; full range by default,
+        #     so unset viewport reproduces the pre-viewport rendering) ---
+        view_start = max(0, self._view_start)
+        view_end = self._resolved_view_end()
+        view_len = max(1, view_end - view_start + 1)
+
+        # --- X-axis ticks (labelled in original, non-sliced index space) ---
+        if view_len > 1:
+            n_x_ticks = min(view_len, max(2, int(plot_w // 80)))
+            x_tick_step = (view_len - 1) / max(1, n_x_ticks - 1)
             for i in range(n_x_ticks):
-                idx = int(round(i * x_tick_step))
-                x_frac = idx / (num_points - 1)
-                x_px = plot_left + x_frac * plot_w
+                rel_idx = int(round(i * x_tick_step))
+                x_px = index_to_pixel(rel_idx, view_len, plot_left, plot_w)
                 painter.setPen(axis_pen)
                 painter.drawText(
                     int(x_px - 12), int(plot_top + plot_h + 14),
-                    str(idx + 1),
+                    str(view_start + rel_idx + 1),
                 )
 
         # --- Axes boundary ---
@@ -339,30 +556,36 @@ class GraphQuickItem(QQuickPaintedItem):
         painter.drawLine(int(plot_left), int(plot_top), int(plot_left), int(plot_top + plot_h))
         painter.drawLine(int(plot_left), int(plot_top + plot_h), int(plot_left + plot_w), int(plot_top + plot_h))
 
-        # --- Figure out max series length ---
-        max_len = max(len(s) for s in self._series_data) if self._series_data else 0
-        if max_len < 1:
-            return
-
-        # --- Draw each series ---
+        # --- Draw each series (sliced to the current viewport) ---
+        min_pt: tuple[float, float] | None = None
+        max_pt: tuple[float, float] | None = None
+        min_seen = math.inf
+        max_seen = -math.inf
         for si, series in enumerate(self._series_data):
-            if len(series) < 1:
+            hi = min(len(series) - 1, view_end)
+            sliced = series[view_start:hi + 1] if view_start <= hi else []
+            if not sliced:
                 continue
             color = self._series_colors[si % len(self._series_colors)]
             pen = QPen(color, 2)
             painter.setPen(pen)
 
             pts: list[tuple[float, float]] = []
-            for i, val in enumerate(series):
+            for i, val in enumerate(sliced):
                 try:
                     v = float(val)
                 except (ValueError, TypeError):
                     continue
-                x_frac = i / (max_len - 1) if max_len > 1 else 0.5
-                y_frac = 1.0 - ((v - self._min_y) / y_range) if y_range > 0 else 0.5
-                x_px = plot_left + x_frac * plot_w
-                y_px = plot_top + y_frac * plot_h
+                x_px = index_to_pixel(i, view_len, plot_left, plot_w)
+                y_px = value_to_pixel(v, self._min_y, self._max_y, plot_top, plot_h)
                 pts.append((x_px, y_px))
+                if self._show_min_max_markers:
+                    if v < min_seen:
+                        min_seen = v
+                        min_pt = (x_px, y_px)
+                    if v > max_seen:
+                        max_seen = v
+                        max_pt = (x_px, y_px)
 
             if len(pts) < 2:
                 if len(pts) == 1:
@@ -375,6 +598,19 @@ class GraphQuickItem(QQuickPaintedItem):
                     int(pts[i + 1][0]), int(pts[i + 1][1]),
                 )
 
+        # --- Min/max markers (replay chart only; PopupChartForm.cs parity) ---
+        if self._show_min_max_markers:
+            marker_font = QFont()
+            marker_font.setPixelSize(14)
+            marker_font.setBold(True)
+            painter.setFont(marker_font)
+            if max_pt is not None:
+                painter.setPen(QPen(QColor("#FF5757")))
+                painter.drawText(int(max_pt[0] - 6), int(max_pt[1] - 8), "▼")
+            if min_pt is not None:
+                painter.setPen(QPen(QColor("#42A5F5")))
+                painter.drawText(int(min_pt[0] - 6), int(min_pt[1] + 18), "▲")
+
         # --- Legend ---
         if self._show_legend and self._sensor_names:
             legend_font = QFont()

src/pygui/backend/visualization/graph_view.py

@@ -23,6 +23,9 @@ class GraphView(QObject):
     each sensor as a separate line series.
     """
 
+    # Set lazily in updateTrend (guarded by hasattr); declared for mypy.
+    _trend_line: Any
+
     # ---- signals ----
     dataReady = Signal(object)  # {"success": bool, "sensory_names": list, "series": list}
 
@@ -227,7 +230,7 @@ class GraphView(QObject):
             index_a, index_b = path[i]
             if index_a < len(a) and index_b < len(b):
                 line = pg.InfiniteLine(pos=index_a, angle=90, pen=pg.mkPen("#666666", width=1,
-                style=Qt.DashLine))
+                style=Qt.PenStyle.DashLine))
                 self._plot_widget.addItem(line)
 
             self._plot_widget.setTitle("DTW Comparison")

src/pygui/backend/visualization/rbf_heatmap.py

@@ -6,6 +6,7 @@ from __future__ import annotations
 
 import numpy as np
 from scipy.interpolate import RBFInterpolator
+from scipy.ndimage import zoom as _ndi_zoom
 
 try:
     import cupy as _cupy  # type: ignore
@@ -17,6 +18,17 @@ except Exception:
 _KERNEL = "thin_plate_spline"
 _SMOOTHING = 0.0
 
+# Sensor density (≤244 points) carries no more spatial information than this;
+# evaluating on a bigger grid than the widget's pixel size just burns CPU that
+# a GPU-bilinear QImage upscale reproduces visually. See alpha-release-polish-plan.md §2.2.
+GRID_RES = 100
+
+# Bilinear-scaling the raw 100x100 field straight to widget size shows visible
+# facets on real (higher-contrast) sensor data. A cheap cubic pre-smooth of the
+# field (RBF grid is the expensive part; resampling a small array is not) removes
+# the facets before the final QImage upscale does the rest.
+REFINE_FACTOR = 2
+
 
 def interpolate_field(
     xs: np.ndarray,
@@ -28,26 +40,30 @@ def interpolate_field(
     extent: tuple[float, float, float, float],  # (xmin, xmax, ymin, ymax) in mm
     round_clip: bool = False,
 ) -> np.ndarray:
-    """Return a (height, width) float64 array of interpolated values.
+    """Return a float64 array of interpolated values, capped at GRID_RES per side.
 
     Args:
         xs, ys:      sensor positions in mm (1-D arrays, length N)
         vs:          sensor values (length N)
-        width/height: output grid dimensions in pixels
+        width/height: desired output dimensions in pixels; the grid is solved at
+                      min(dim, GRID_RES) and the caller upscales the resulting image
         extent:      (xmin, xmax, ymin, ymax) in the same mm space as xs/ys
         round_clip:  if True, pixels outside the inscribed ellipse become NaN
     """
     coords = np.column_stack([xs, ys])
     rbf = RBFInterpolator(coords, vs, kernel=_KERNEL, smoothing=_SMOOTHING)
 
+    grid_w = min(width, GRID_RES)
+    grid_h = min(height, GRID_RES)
+
     xmin, xmax, ymin, ymax = extent
-    gx = np.linspace(xmin, xmax, width)
-    gy = np.linspace(ymin, ymax, height)
+    gx = np.linspace(xmin, xmax, grid_w)
+    gy = np.linspace(ymin, ymax, grid_h)
     grid_x, grid_y = np.meshgrid(gx, gy)
     flat = np.column_stack([grid_x.ravel(), grid_y.ravel()])
 
     # RBFInterpolator always runs on CPU; CuPy only accelerates other ops if added later
-    field = rbf(flat).reshape(height, width)
+    field = rbf(flat).reshape(grid_h, grid_w)
 
     if round_clip:
         cx = (xmin + xmax) / 2
@@ -57,5 +73,33 @@ def interpolate_field(
         dist = ((grid_x - cx) / rx) ** 2 + ((grid_y - cy) / ry) ** 2
         field = np.where(dist <= 1.0, field, np.nan)
 
-    return field.astype(np.float64)
+    result: np.ndarray = field.astype(np.float64)
+    return result
+
+
+def refine_field(field: np.ndarray, factor: int = REFINE_FACTOR) -> np.ndarray:
+    """Cubic-upsample a coarse (NaN-free) field by `factor`.
+
+    Callers that need a circular boundary should pass an *unclipped* field
+    (round_clip=False) and mask with ellipse_alpha() afterwards — cubic
+    resampling across a NaN/zero-filled hole rings at the boundary, and any
+    mask derived from the coarse grid keeps its staircase when upscaled.
+    """
+    refined: np.ndarray = _ndi_zoom(field, factor, order=3)
+    return refined
+
+
+def ellipse_alpha(height: int, width: int, feather_px: float = 1.2) -> np.ndarray:
+    """Anti-aliased coverage mask (0..1) of the ellipse inscribed in the grid.
+
+    Computed analytically at the target resolution — unlike upsampling a
+    binary clip mask from the coarse RBF grid, this cannot show grid steps.
+    `feather_px` is the half-width of the linear edge ramp, in grid pixels.
+    """
+    y = (np.arange(height) + 0.5) / height * 2.0 - 1.0
+    x = (np.arange(width) + 0.5) / width * 2.0 - 1.0
+    yy, xx = np.meshgrid(y, x, indexing="ij")
+    r = np.sqrt(xx * xx + yy * yy)
+    f = feather_px * 2.0 / min(width, height)
+    return np.clip((1.0 - r) / f + 0.5, 0.0, 1.0)
 

src/pygui/backend/visualization/trend_chart_item.py

@@ -1,12 +1,15 @@
 """QQuickPaintedItem trend chart — running-average temperature over time.
 
-Renders a single polyline series (per-frame average temperatures) using QPainter.
-Mirrors the @QmlElement registration pattern used by `WaferMapItem` so it can
-be embedded directly in QML via `import ISC.Wafer` and used as `TrendChartItem { }`.
+Renders a single polyline series (per-frame average temperatures) over a fixed
+0-200°C Y axis and an elapsed-seconds X axis, using a bounded 60-second
+rolling window. Mirrors the @QmlElement registration pattern used by
+`WaferMapItem` so it can be embedded directly in QML via `import ISC.Wafer`
+and used as `TrendChartItem { }`.
 
-The series is driven by the existing `streamController.trendData` signal, which
-emits a JSON-encoded list of floats from both review-mode replay and live-mode
-streaming.
+The series is driven by `streamController.trendDelta` (one new
+`[elapsed_s, value]` point per live frame) and cleared on
+`streamController.trendReset` (new stream started). See
+docs/adr/0001-trend-chart-axes-standardization.md.
 """
 from __future__ import annotations
 
@@ -19,17 +22,23 @@ from PySide6.QtGui import QColor, QFont, QPainter, QPen, QPolygon
 from PySide6.QtQml import QmlElement
 from PySide6.QtQuick import QQuickPaintedItem
 
+from pygui.backend.visualization.chart_geometry import elapsed_to_pixel, value_to_pixel
+
 log = logging.getLogger(__name__)
 
 QML_IMPORT_NAME = "ISC.Wafer"
 QML_IMPORT_MAJOR_VERSION = 1
 
+WINDOW_SECONDS = 60.0
+Y_MIN = 0.0
+Y_MAX = 200.0
+Y_TICKS = (0, 40, 80, 120, 160, 200)
+
 
 @QmlElement
 class TrendChartItem(QQuickPaintedItem):
-    """Painted trend chart; driven by a list of floats via the `data` property."""
+    """Painted trend chart; driven by incremental (elapsed_s, value) points."""
 
-    dataChanged = Signal()
     hasDataChanged = Signal()
     lineColorChanged = Signal()
     gridColorChanged = Signal()
@@ -42,41 +51,35 @@ class TrendChartItem(QQuickPaintedItem):
         self.setAntialiasing(True)
         self.setFillColor(QColor("transparent"))
 
-        self._data: list[float] = []
+        self._points: list[tuple[float, float]] = []
         self._padding: int = 8
+        # Separate from `_padding` (breathing room around the plot area): these
+        # reserve space for the axis labels themselves, which are wider than
+        # `_padding` alone — that mismatch is what clipped y-axis text before.
+        self._margin_left: int = 48
+        self._margin_bottom: int = 30
+        # Top tick label is drawn centered on the plot's top edge (y_px - 7),
+        # so the plot needs headroom or the label kisses the card border.
+        self._margin_top: int = 10
         self._line_color = QColor("#5B9DF5")
         self._grid_color = QColor("#2A3441")
         self._text_color = QColor("#CBD5E1")
 
     # ── Qt properties ─────────────────────────────────────────────────────
 
-    @Property("QVariantList", notify=dataChanged)
-    def data(self) -> list[float]:
-        return self._data
-
-    @data.setter
-    def data(self, val) -> None:
-        coerced = self._coerce_floats(val)
-        if coerced == self._data:
-            return
-        self._data = coerced
-        self.dataChanged.emit()
-        self.hasDataChanged.emit()
-        self.update()
-
     @Property(bool, notify=hasDataChanged)
     def hasData(self) -> bool:
-        """True when the data list has at least one point.
+        """True when at least one point is buffered.
 
-        QML can bind to this safely (QVariantList `.length` is not bindable).
+        QML can bind to this safely (a plain list length is not bindable).
         """
-        return len(self._data) > 0
+        return len(self._points) > 0
 
     @Property(QColor, notify=lineColorChanged)
     def lineColor(self) -> QColor:
         return self._line_color
 
-    @lineColor.setter
+    @lineColor.setter  # type: ignore[no-redef]
     def lineColor(self, c: QColor) -> None:
         if c == self._line_color:
             return
@@ -88,7 +91,7 @@ class TrendChartItem(QQuickPaintedItem):
     def gridColor(self) -> QColor:
         return self._grid_color
 
-    @gridColor.setter
+    @gridColor.setter  # type: ignore[no-redef]
     def gridColor(self, c: QColor) -> None:
         if c == self._grid_color:
             return
@@ -100,7 +103,7 @@ class TrendChartItem(QQuickPaintedItem):
     def textColor(self) -> QColor:
         return self._text_color
 
-    @textColor.setter
+    @textColor.setter  # type: ignore[no-redef]
     def textColor(self, c: QColor) -> None:
         if c == self._text_color:
             return
@@ -112,7 +115,7 @@ class TrendChartItem(QQuickPaintedItem):
     def padding(self) -> int:
         return self._padding
 
-    @padding.setter
+    @padding.setter  # type: ignore[no-redef]
     def padding(self, val: int) -> None:
         v = max(0, int(val))
         if v == self._padding:
@@ -121,24 +124,48 @@ class TrendChartItem(QQuickPaintedItem):
         self.paddingChanged.emit()
         self.update()
 
-    # ── Convenience slot for QML: accept a JSON string from a Signal(str) ──
+    # ── slots for QML: streamController.trendDelta / trendReset ────────────
 
     @Slot(str)
-    def setDataFromJson(self, avgs_json: str) -> None:
-        """Slot for QML Connections handler: parse JSON array and update data.
+    def appendDelta(self, delta_json: str) -> None:
+        """Append new (elapsed_s, value) points and prune the 60s window.
 
-        Mirrors `streamController.trendData` (which emits JSON-encoded floats).
+        Mirrors `streamController.trendDelta`, which emits one new pair per
+        live frame as `[[elapsed_s, value], ...]`.
         """
         try:
-            parsed = json.loads(avgs_json) if avgs_json else []
+            parsed = json.loads(delta_json) if delta_json else []
         except (json.JSONDecodeError, TypeError) as exc:
-            log.error("TrendChartItem: failed to parse trend JSON: %s", exc)
+            log.error("TrendChartItem: failed to parse trend delta JSON: %s", exc)
             return
-        coerced = self._coerce_floats(parsed)
-        if coerced == self._data:
+
+        had_data = len(self._points) > 0
+        added = False
+        for pair in parsed:
+            try:
+                elapsed, value = float(pair[0]), float(pair[1])
+            except (TypeError, ValueError, IndexError):
+                continue
+            self._points.append((elapsed, value))
+            added = True
+
+        if not added:
             return
-        self._data = coerced
-        self.dataChanged.emit()
+
+        latest_elapsed = self._points[-1][0]
+        cutoff = latest_elapsed - WINDOW_SECONDS
+        self._points = [p for p in self._points if p[0] >= cutoff]
+
+        if not had_data:
+            self.hasDataChanged.emit()
+        self.update()
+
+    @Slot()
+    def clearTrend(self) -> None:
+        """Clear all buffered points (new stream started)."""
+        if not self._points:
+            return
+        self._points = []
         self.hasDataChanged.emit()
         self.update()
 
@@ -153,57 +180,39 @@ class TrendChartItem(QQuickPaintedItem):
         if w <= 0 or h <= 0:
             return
 
-        plot_rect = QRectF(self._padding, self._padding,
-                           max(1, w - 2 * self._padding),
-                           max(1, h - 2 * self._padding))
+        left = self._padding + self._margin_left
+        top = self._padding + self._margin_top
+        bottom_inset = self._padding + self._margin_bottom
+        plot_rect = QRectF(left, top,
+                           max(1, w - left - self._padding),
+                           max(1, h - top - bottom_inset))
 
         self._draw_grid(painter, plot_rect)
 
-        if len(self._data) < 2:
+        if len(self._points) < 2:
             return
 
-        y_min, y_max = self._y_range()
-        self._draw_axes_labels(painter, plot_rect, y_min, y_max)
-        self._draw_line(painter, plot_rect, y_min, y_max)
+        window_end = self._points[-1][0]
+        window_start = max(0.0, window_end - WINDOW_SECONDS)
+        self._draw_axes_labels(painter, plot_rect, window_start, window_end)
+        self._draw_line(painter, plot_rect, window_start, window_end)
 
     # ── internals ─────────────────────────────────────────────────────────
 
-    def _coerce_floats(self, val) -> list[float]:
-        if not val:
-            return []
-        out: list[float] = []
-        for v in val:
-            try:
-                out.append(float(v))
-            except (TypeError, ValueError):
-                continue
-        return out
+    def _x_to_px(self, elapsed: float, window_start: float, window_end: float, plot_rect: QRectF) -> float:
+        return elapsed_to_pixel(elapsed, window_start, window_end, plot_rect.left(), plot_rect.width())
 
-    def _y_range(self) -> tuple[float, float]:
-        lo = min(self._data)
-        hi = max(self._data)
-        if hi - lo < 1e-9:
-            return lo - 5.0, hi + 5.0
-        buf = (hi - lo) * 0.1
-        return lo - buf, hi + buf
-
-    def _x_to_px(self, i: int, n: int, plot_rect: QRectF) -> float:
-        if n <= 1:
-            return plot_rect.left()
-        return plot_rect.left() + (i / (n - 1)) * plot_rect.width()
-
-    def _y_to_px(self, v: float, y_min: float, y_max: float, plot_rect: QRectF) -> float:
-        if y_max - y_min < 1e-9:
-            return plot_rect.center().y()
-        t = (v - y_min) / (y_max - y_min)
-        return plot_rect.bottom() - t * plot_rect.height()
+    def _y_to_px(self, value: float, plot_rect: QRectF) -> float:
+        px = value_to_pixel(value, Y_MIN, Y_MAX, plot_rect.top(), plot_rect.height())
+        # Clamp: a sensor reading outside 0-200°C shouldn't paint outside the widget.
+        return max(plot_rect.top(), min(plot_rect.bottom(), px))
 
     def _draw_grid(self, painter: QPainter, plot_rect: QRectF) -> None:
         pen = QPen(self._grid_color)
         pen.setWidthF(1.0)
         pen.setCosmetic(True)
         painter.setPen(pen)
-        rows = 4
+        rows = len(Y_TICKS) - 1
         for i in range(rows + 1):
             y = plot_rect.top() + (i / rows) * plot_rect.height()
             painter.drawLine(int(plot_rect.left()), int(y),
@@ -213,31 +222,69 @@ class TrendChartItem(QQuickPaintedItem):
         self,
         painter: QPainter,
         plot_rect: QRectF,
-        y_min: float,
-        y_max: float,
+        window_start: float,
+        window_end: float,
     ) -> None:
         painter.setPen(self._text_color)
         font = QFont(painter.font())
         font.setPointSizeF(max(7.0, font.pointSizeF() * 0.85))
         painter.setFont(font)
-        rows = 4
-        for i in range(rows + 1):
-            t = i / rows
-            y_val = y_max - t * (y_max - y_min)
-            y_px = plot_rect.top() + t * plot_rect.height()
-            label = f"{y_val:.1f}"
-            painter.drawText(QRectF(0, y_px - 7, self._padding, 14),
+
+        title_w = 14  # leftmost sliver reserved for the rotated "Temp" title
+        label_w = self._margin_left - 4 - title_w  # 4px gutter before the plot area
+        for tick in reversed(Y_TICKS):
+            y_px = self._y_to_px(tick, plot_rect)
+            painter.drawText(QRectF(title_w, y_px - 7, label_w, 14),
                              Qt.AlignmentFlag.AlignRight | Qt.AlignmentFlag.AlignVCenter,
-                             label)
+                             str(tick))
+
+        # X-axis: elapsed seconds within the current rolling window.
+        cols = 4
+        y_px = plot_rect.bottom() + 4
+        for i in range(cols + 1):
+            t_val = window_start + (i / cols) * (window_end - window_start)
+            x_px = self._x_to_px(t_val, window_start, window_end, plot_rect)
+            label = f"{t_val:.0f}"
+            if i == 0:
+                rect = QRectF(x_px, y_px, 40, 14)
+                align = Qt.AlignmentFlag.AlignLeft
+            elif i == cols:
+                # Right-anchor inside the plot so the label never clips off-widget
+                rect = QRectF(x_px - 40, y_px, 40, 14)
+                align = Qt.AlignmentFlag.AlignRight
+            else:
+                rect = QRectF(x_px - 20, y_px, 40, 14)
+                align = Qt.AlignmentFlag.AlignHCenter
+            painter.drawText(rect, align | Qt.AlignmentFlag.AlignTop, label)
+
+        self._draw_axis_titles(painter, plot_rect, title_w, y_px + 18)
+
+    def _draw_axis_titles(
+        self,
+        painter: QPainter,
+        plot_rect: QRectF,
+        title_w: float,
+        x_label_bottom: float,
+    ) -> None:
+        # Y axis: "Temp", rotated upright, centered along the plot's height.
+        painter.save()
+        painter.translate(title_w / 2, plot_rect.center().y())
+        painter.rotate(-90)
+        painter.drawText(QRectF(-plot_rect.height() / 2, -7, plot_rect.height(), 14),
+                         Qt.AlignmentFlag.AlignCenter, "Temp (°C)")
+        painter.restore()
+
+        # X axis: "Time", centered under the elapsed-seconds tick row.
+        painter.drawText(QRectF(plot_rect.left(), x_label_bottom, plot_rect.width(), 14),
+                         Qt.AlignmentFlag.AlignHCenter | Qt.AlignmentFlag.AlignTop, "Time")
 
     def _draw_line(
         self,
         painter: QPainter,
         plot_rect: QRectF,
-        y_min: float,
-        y_max: float,
+        window_start: float,
+        window_end: float,
     ) -> None:
-        n = len(self._data)
         pen = QPen(self._line_color)
         pen.setWidthF(2.0)
         pen.setCosmetic(True)
@@ -246,15 +293,16 @@ class TrendChartItem(QQuickPaintedItem):
         painter.setPen(pen)
 
         poly = QPolygon()
-        for i, v in enumerate(self._data):
-            px = self._x_to_px(i, n, plot_rect)
-            py = self._y_to_px(v, y_min, y_max, plot_rect)
+        for elapsed, value in self._points:
+            px = self._x_to_px(elapsed, window_start, window_end, plot_rect)
+            py = self._y_to_px(value, plot_rect)
             poly.append(QPoint(int(px), int(py)))
         painter.drawPolyline(poly)
 
         # Trailing dot at the last data point
-        last_x = int(self._x_to_px(n - 1, n, plot_rect))
-        last_y = int(self._y_to_px(self._data[-1], y_min, y_max, plot_rect))
+        last_elapsed, last_value = self._points[-1]
+        last_x = int(self._x_to_px(last_elapsed, window_start, window_end, plot_rect))
+        last_y = int(self._y_to_px(last_value, plot_rect))
         painter.setBrush(self._line_color)
         painter.setPen(Qt.PenStyle.NoPen)
         radius = 3

src/pygui/backend/visualization/wafer_map_item.py

@@ -14,7 +14,7 @@ import logging
 import math
 
 import numpy as np
-from PySide6.QtCore import Property, QPoint, Qt, Signal, Slot
+from PySide6.QtCore import Property, QPoint, QRectF, Qt, Signal, Slot
 from PySide6.QtGui import (
     QBrush,
     QColor,
@@ -27,11 +27,69 @@ from PySide6.QtGui import (
 from PySide6.QtQml import QmlElement
 from PySide6.QtQuick import QQuickPaintedItem
 
-from pygui.backend.visualization.rbf_heatmap import interpolate_field
+from pygui.backend.models.frame_stats import compute_stats
+from pygui.backend.visualization.rbf_heatmap import (
+    ellipse_alpha,
+    interpolate_field,
+    refine_field,
+)
 from pygui.backend.wafer.zwafer_models import Sensor
 
 log = logging.getLogger(__name__)
 
+
+def parse_thickness_csv(file_path: str) -> tuple[list[list[float]], str]:
+    """Parse a customer thickness CSV into [x, y, t2] points (mm from center).
+
+    Expected columns (C# parity): Lot Start Time, RC, Site#, Slot#, T2,
+    NGOF, Wafer X, Wafer Y. Only the first wafer (first Slot# value) is read.
+    Returns (points, error) — error is "" on success.
+    """
+    import csv
+
+    points: list[list[float]] = []
+    slot: str | None = None
+    try:
+        with open(file_path, newline="") as fh:
+            reader = csv.reader(fh)
+            header = next(reader, None)
+            if header is None:
+                return [], "Unable to read header row from CSV file."
+            if header and header[-1] == "":  # trailing comma
+                header = header[:-1]
+            nfields = len(header)
+            if nfields != 8:
+                return [], "Incorrect field count in CSV header row."
+            for lno, row in enumerate(reader, start=2):
+                if row and row[-1] == "":
+                    row = row[:-1]
+                if len(row) != nfields:
+                    return [], f"Incorrect field count in CSV row {lno}"
+                if slot is None:
+                    slot = row[3]
+                elif row[3] != slot:
+                    break
+                try:
+                    t2, x, y = float(row[4]), float(row[6]), float(row[7])
+                except ValueError:
+                    return [], f"Malformed value in CSV row {lno}"
+                points.append([x, y, t2])
+    except OSError as exc:
+        return [], f"Unable to read CSV file: {exc}"
+    if not points:
+        return [], "No data found in CSV file."
+    return points, ""
+
+
+def readout_text(values: list[float]) -> str:
+    """Full READOUT stats line for the export footer; '' when no data."""
+    if not values:
+        return ""
+    s = compute_stats(values)
+    return (f"Sensors: {len(values)}   Min: {s.min:.2f}°C (#{s.min_index + 1})   "
+            f"Max: {s.max:.2f}°C (#{s.max_index + 1})   Diff: {s.diff:.2f}   "
+            f"Avg: {s.avg:.2f}   σ: {s.sigma:.2f}   3σ: {s.three_sigma:.2f}")
+
 QML_IMPORT_NAME = "ISC.Wafer"
 QML_IMPORT_MAJOR_VERSION = 1
 
@@ -47,11 +105,14 @@ class WaferMapItem(QQuickPaintedItem):
     marginChanged   = Signal()
     blendChanged    = Signal()
     showLabelsChanged = Signal()
+    showExtremesChanged = Signal()
     colorsChanged   = Signal()
     shapeChanged    = Signal()
     sizeChanged     = Signal()
     thicknessChanged = Signal()
     showThicknessChanged = Signal()
+    hoveredIndexChanged = Signal()
+    hoverScaleChanged = Signal()
 
 
     def __init__(self, parent=None):
@@ -63,11 +124,16 @@ class WaferMapItem(QQuickPaintedItem):
         self._margin:   float = 1.0
         self._blend:    float = 0.0
         self._show_labels: bool = True
+        self._show_extremes: bool = True
         self._shape: str = "round"
         self._size: float = 300.0
-        self._thickness_data: list[float] = []
+        self._thickness_data: list[list[float]] = []  # [x_mm, y_mm, t2] triples
         self._show_thickness: bool = False
         self._thickness_heatmap:QImage | None = None
+        # Hover highlight: index of the marker under the pointer (-1 = none)
+        # and a 1.0->~1.5 grow factor driven by a QML Behavior for a smooth animation.
+        self._hovered_index: int = -1
+        self._hover_scale: float = 1.0
 
         # Dark-theme color defaults (match Theme.qml tokens)
         self._ring_color     = QColor("#2A3441")   # waferRingColor  (toneBorder)
@@ -81,6 +147,12 @@ class WaferMapItem(QQuickPaintedItem):
         self._markers: dict[int, tuple[int, int]] = {}  # sensor index → (px, py)
         self._marker_r: int = 4
         self._heatmap:  QImage | None = None
+        # Size the markers/heatmap were last computed against. On first activation
+        # (e.g. a freshly-created Loader item) width()/height() can still be 0/stale
+        # when `sensors` is first set, computing degenerate marker positions that
+        # never get retried. paint() re-checks this every frame so geometry that
+        # settles after property assignment still gets picked up.
+        self._last_draw_size: int = -1
 
         self.widthChanged.connect(self._on_resize)
         self.heightChanged.connect(self._on_resize)
@@ -91,7 +163,7 @@ class WaferMapItem(QQuickPaintedItem):
     def sensors(self) -> list:
         return [{"label": s.label, "x": s.x, "y": s.y} for s in self._sensors]
 
-    @sensors.setter
+    @sensors.setter  # type: ignore[no-redef]
     def sensors(self, val: list) -> None:
         self._sensors = [
             Sensor(
@@ -111,7 +183,7 @@ class WaferMapItem(QQuickPaintedItem):
     def values(self) -> list:
         return self._values
 
-    @values.setter
+    @values.setter  # type: ignore[no-redef]
     def values(self, val: list) -> None:
         self._values = list(val or [])
         self._rebuild_heatmap()
@@ -122,7 +194,7 @@ class WaferMapItem(QQuickPaintedItem):
     def bands(self) -> list:
         return self._bands
 
-    @bands.setter
+    @bands.setter  # type: ignore[no-redef]
     def bands(self, val: list) -> None:
         self._bands = list(val or [])
         self.bandsChanged.emit()
@@ -132,7 +204,7 @@ class WaferMapItem(QQuickPaintedItem):
     def target(self) -> float:
         return self._target
 
-    @target.setter
+    @target.setter  # type: ignore[no-redef]
     def target(self, val: float) -> None:
         self._target = float(val)
         self._rebuild_heatmap()
@@ -143,7 +215,7 @@ class WaferMapItem(QQuickPaintedItem):
     def margin(self) -> float:
         return self._margin
 
-    @margin.setter
+    @margin.setter  # type: ignore[no-redef]
     def margin(self, val: float) -> None:
         self._margin = float(val)
         self._rebuild_heatmap()
@@ -154,7 +226,7 @@ class WaferMapItem(QQuickPaintedItem):
     def blend(self) -> float:
         return self._blend
 
-    @blend.setter
+    @blend.setter  # type: ignore[no-redef]
     def blend(self, val: float) -> None:
         self._blend = max(0.0, min(1.0, float(val)))
         if self._blend > 0 and self._heatmap is None:
@@ -166,17 +238,27 @@ class WaferMapItem(QQuickPaintedItem):
     def showLabels(self) -> bool:
         return self._show_labels
 
-    @showLabels.setter
+    @showLabels.setter  # type: ignore[no-redef]
     def showLabels(self, val: bool) -> None:
         self._show_labels = bool(val)
         self.showLabelsChanged.emit()
         self.update()
 
+    @Property(bool, notify=showExtremesChanged)
+    def showExtremes(self) -> bool:
+        return self._show_extremes
+
+    @showExtremes.setter  # type: ignore[no-redef]
+    def showExtremes(self, val: bool) -> None:
+        self._show_extremes = bool(val)
+        self.showExtremesChanged.emit()
+        self.update()
+
     @Property(str, notify=shapeChanged)
     def shape(self) -> str:
         return self._shape
 
-    @shape.setter
+    @shape.setter  # type: ignore[no-redef]
     def shape(self, val: str) -> None:
         self._shape = str(val).lower()
         self._rebuild()
@@ -186,7 +268,7 @@ class WaferMapItem(QQuickPaintedItem):
     def size(self) -> float:
         return self._size
 
-    @size.setter
+    @size.setter  # type: ignore[no-redef]
     def size(self, val: float) -> None:
         self._size = float(val)
         self._rebuild()
@@ -194,54 +276,95 @@ class WaferMapItem(QQuickPaintedItem):
 
     @Property("QVariantList", notify=thicknessChanged)
     def thicknessData(self) -> list:
+        """Thickness measurement points as [x_mm, y_mm, t2] triples."""
         return self._thickness_data
 
-    @thicknessData.setter
+    @thicknessData.setter  # type: ignore[no-redef]
     def thicknessData(self, val:list) -> None:
-        self._thickness_data = list(val or [])
+        self._thickness_data = [list(p) for p in (val or [])]
         self._rebuild_thickness()
         self.thicknessChanged.emit()
+        self.update()
+
+    @Property(bool, notify=thicknessChanged)
+    def hasThickness(self) -> bool:
+        return bool(self._thickness_data)
+
+    @Slot(str, result=str)
+    def loadThickness(self, file_path: str) -> str:
+        """Load a customer thickness CSV; returns error message, '' on success."""
+        points, err = parse_thickness_csv(file_path)
+        if err:
+            return err
+        self._thickness_data = points
+        self._rebuild_thickness()
+        self.thicknessChanged.emit()
+        self.update()
+        return ""
         self.update
 
     @Property(bool, notify=showThicknessChanged)
     def showThickness(self) -> bool:
         return self._show_thickness
 
-    @showThickness.setter
+    @showThickness.setter  # type: ignore[no-redef]
     def showThickness(self, val: bool) -> None:
         self._show_thickness = bool(val)
         self.showThicknessChanged.emit()
         self.update()
 
+    @Property(int, notify=hoveredIndexChanged)
+    def hoveredIndex(self) -> int:
+        return self._hovered_index
+
+    @hoveredIndex.setter  # type: ignore[no-redef]
+    def hoveredIndex(self, val: int) -> None:
+        val = int(val)
+        if val == self._hovered_index:
+            return
+        self._hovered_index = val
+        self.hoveredIndexChanged.emit()
+        self.update()
+
+    @Property(float, notify=hoverScaleChanged)
+    def hoverScale(self) -> float:
+        return self._hover_scale
+
+    @hoverScale.setter  # type: ignore[no-redef]
+    def hoverScale(self, val: float) -> None:
+        self._hover_scale = float(val)
+        self.hoverScaleChanged.emit()
+        self.update()
+
     # Colour properties — QML can bind these to Theme tokens
     @Property(QColor, notify=colorsChanged)
     def ringColor(self) -> QColor: return self._ring_color
-    @ringColor.setter
+    @ringColor.setter  # type: ignore[no-redef]
     def ringColor(self, c: QColor) -> None: self._ring_color = c; self.update()
 
     @Property(QColor, notify=colorsChanged)
     def axisColor(self) -> QColor: return self._axis_color
-    @axisColor.setter
+    @axisColor.setter  # type: ignore[no-redef]
     def axisColor(self, c: QColor) -> None: self._axis_color = c; self.update()
 
     @Property(QColor, notify=colorsChanged)
     def lowColor(self) -> QColor: return self._low_color
-    @lowColor.setter
+    @lowColor.setter  # type: ignore[no-redef]
     def lowColor(self, c: QColor) -> None: self._low_color = c; self.update()
 
     @Property(QColor, notify=colorsChanged)
     def inRangeColor(self) -> QColor: return self._in_range_color
-    @inRangeColor.setter
+    @inRangeColor.setter  # type: ignore[no-redef]
     def inRangeColor(self, c: QColor) -> None: self._in_range_color = c; self.update()
 
     @Property(QColor, notify=colorsChanged)
     def highColor(self) -> QColor: return self._high_color
-    @highColor.setter
+    @highColor.setter  # type: ignore[no-redef]
     def highColor(self, c: QColor) -> None: self._high_color = c; self.update()
 
     @Property(QColor, notify=colorsChanged)
     def textColor(self) -> QColor: return self._text_color
-    @textColor.setter
+    @textColor.setter  # type: ignore[no-redef]
     def textColor(self, c: QColor) -> None: self._text_color = c; self.update()
 
     # ── slots ─────────────────────────────────────────────────────────────
@@ -255,70 +378,125 @@ class WaferMapItem(QQuickPaintedItem):
                 return idx
         return -1
 
+    # TODO P6.1: build batch export on top of this single-frame export
+    #   THINKING: export_image() already does the hard part (grabToImage → PNG);
+    #   batch export is just a loop over file_browser.files that loads each CSV
+    #   through the existing wafer-map pipeline and calls this per file into a
+    #   chosen output dir, plus an optional summary CSV of (file, min/max/mean).
+    #   No new rendering code needed — see docs/pending/alpha-release-polish-plan.md §6.1.
     @Slot(str, result=bool)
-    def export_image(self, file_path: str) -> bool:
+    @Slot(str, str, result=bool)
+    def export_image(self, file_path: str, extra: str = "") -> bool:
         """Export the current wafer map rendering to a PNG file
 
         Args:
-            file_pat: Absolute path for the output PNG.
+            file_path: Absolute path for the output PNG.
+            extra: Optional second footer line (live stream metrics).
 
         Returns:
         True on success, False on failure
         """
-        if not file_path:
+        if not file_path or not self._values:
+            # No file loaded / no stream played yet — only the empty template
+            # would render, which isn't a meaningful export.
             return False
         try:
-            result = self.grabToImage()
-            img = result.image()
-            img.save(file_path, "PNG")
-            return True
+            # Render synchronously via paint() into our own image —
+            # grabToImage() resolves on a later render frame, so its result
+            # is null when read immediately (the old silent failure).
+            w, h = int(self.width()), int(self.height())
+            if w <= 0 or h <= 0:
+                return False
+            lines = [ln for ln in (readout_text(self._values), extra) if ln]
+            footer_h = 28 * len(lines)
+            img = QImage(w, h + footer_h, QImage.Format.Format_ARGB32)
+            img.fill(0)  # transparent background
+            painter = QPainter(img)
+            self.paint(painter)
+            if lines:
+                painter.fillRect(QRectF(0, h, w, footer_h), QColor("#101014"))
+                painter.setPen(QColor("#CBD5E1"))
+                for i, line in enumerate(lines):
+                    painter.drawText(QRectF(0, h + 28 * i, w, 28),
+                                     Qt.AlignmentFlag.AlignCenter, line)
+            painter.end()
+            return bool(img.save(file_path))
         except Exception as e:
             log.error("Export failed: %s", e)
             return False
 
+
     # ── internal ─────────────────────────────────────────────────────────
 
+    def _paint_extremes(self, painter: QPainter) -> None:
+        """Ring the hottest (high color) and coldest (low color) markers."""
+        if not self._show_extremes or not self._values or not self._markers:
+            return
+        s = compute_stats(self._values)
+        ring_r = self._marker_r + 5
+        painter.setBrush(Qt.BrushStyle.NoBrush)
+        for idx, color in ((s.max_index, self._high_color),
+                           (s.min_index, self._low_color)):
+            if idx not in self._markers:
+                continue
+            px, py = self._markers[idx]
+            painter.setPen(QPen(color, 2))
+            painter.drawEllipse(px - ring_r, py - ring_r, 2 * ring_r, 2 * ring_r)
+
     def _rebuild_thickness(self) -> None:
-        """Interpolate thickness data into a gray/orange heatmap QImage."""
-        if not self._sensors or not self._thickness_data:
+        """Interpolate thickness points into a gray/orange heatmap QImage."""
+        if not self._thickness_data:
             self._thickness_heatmap = None
             return
         ds = self._draw_size()
         r_mm = self._wafer_radius_mm()
-        xs = np.array([s.x for s in self._sensors])
-        ys = np.array([s.y for s in self._sensors])
-        vs = np.array(self._thickness_data[:len(self._sensors)], dtype=float)
-        if len(vs) < len(self._sensors):
-            self._thickness_heatmap = None
-            return
+        pts = np.array(self._thickness_data, dtype=float)
+        xs, ys, vs = pts[:, 0], pts[:, 1], pts[:, 2]
         try:
+            # No round_clip — see _rebuild_heatmap for why the mask is analytic.
             field = interpolate_field(
                 xs, ys, vs,
                 width=ds, height=ds,
                 extent=(-r_mm, r_mm, -r_mm, r_mm),
-                round_clip=(self._shape == "round"),
             )
         except Exception:
             self._thickness_heatmap = None
             return
-        # Gray/orange colormap: map field range 0→1 to gray→orange
-        vmin, vmax = np.nanmin(field), np.nanmax(field)
+        field = refine_field(field)
+        # ponytail: RBF overshoots around outlier sensors, inventing values no
+        # sensor produced (e.g. negative diffs when all diffs are positive).
+        # Clamp to the real data range so color only reflects measured values.
+        field = np.clip(field, vs.min(), vs.max())
+        if self._shape == "round":
+            alpha = ellipse_alpha(*field.shape)
+        else:
+            alpha = np.ones(field.shape)
+        # Color-range bounds from inside the wafer only — the unclipped field
+        # extrapolates wildly toward the square corners, which alpha hides but
+        # a corner-driven vmin/vmax would flatten the visible gradient.
+        inside = field[alpha >= 0.5]
+        vmin, vmax = inside.min(), inside.max()
         span = vmax - vmin or 1.0
+        # Gray/orange colormap: map field range 0→1 to gray→orange
         t = np.clip((field - vmin) / span, 0.0, 1.0)
 
+        gh, gw = field.shape
         # Gray (0.5, 0.5, 0.5) → orange (1.0, 0.65, 0.0)
-        rgb = np.zeros((ds, ds, 3), dtype=np.float32)
+        rgb = np.zeros((gh, gw, 3), dtype=np.float32)
         rgb[:, :, 0] = 0.5 + 0.5 * t
         rgb[:, :, 1] = 0.5 + 0.15 * t
         rgb[:, :, 2] = 0.5 - 0.5 * t
 
         rgb = np.nan_to_num(rgb, nan=0.0)
-        rgba = np.zeros((ds, ds, 4), dtype=np.uint8)
+        rgba = np.zeros((gh, gw, 4), dtype=np.uint8)
         rgba[:, :, :3] = (rgb * 255).astype(np.uint8)
-        rgba[:, :, 3] = np.where(np.isfinite(field), 180, 0).astype(np.uint8)
+        rgba[:, :, 3] = (alpha * 180).astype(np.uint8)
 
-        self._thickness_heatmap = (
-            QImage(rgba.tobytes(), ds, ds, QImage.Format.Format_RGBA8888).copy()
+        grid_img = QImage(rgba.tobytes(), gw, gh, QImage.Format.Format_RGBA8888).copy()
+        self._thickness_heatmap = grid_img.scaled(
+            ds, ds,
+            Qt.AspectRatioMode.IgnoreAspectRatio,
+            Qt.TransformationMode.SmoothTransformation,
         )
 
     def _on_resize(self) -> None:
@@ -342,6 +520,13 @@ class WaferMapItem(QQuickPaintedItem):
         r = max(math.hypot(s.x, s.y) for s in self._sensors)
         return r * 1.05
 
+    # TODO P6.2: reuse this for the edge-to-center delta metric
+    #   THINKING: radial_metrics.py (new) needs the same "which sensors are near
+    #   the edge vs. near the center" bucketing this function already computes
+    #   for ring-line drawing — do NOT re-derive ring boundaries separately, this
+    #   already handles round vs. square wafer shapes correctly (see family_spec.py
+    #   square-wafer work). Outermost group ≈ edge sensors, innermost ≈ center.
+    #   See docs/pending/alpha-release-polish-plan.md §6.2.
     def _sensor_ring_radii_mm(self) -> list[float]:
         """Distinct radial distances of sensor groups, sorted ascending, plus the outer boundary."""
         if not self._sensors:
@@ -391,19 +576,34 @@ class WaferMapItem(QQuickPaintedItem):
             self._heatmap = None
             return
         try:
+            # No round_clip: refine the smooth unclipped field, then mask with an
+            # analytic anti-aliased ellipse (a coarse-grid clip mask upscales jagged).
             field = interpolate_field(
                 xs, ys, vs,
                 width=ds, height=ds,
                 extent=(-r_mm, r_mm, -r_mm, r_mm),
-                round_clip=(self._shape == "round"),
             )
         except Exception:
             self._heatmap = None
             return
-        self._heatmap = self._field_to_qimage(field, ds)
+        field = refine_field(field)
+        # ponytail: RBF overshoots around outlier sensors, inventing values no
+        # sensor produced (e.g. negative diffs when all diffs are positive).
+        # Clamp to the real data range so color only reflects measured values.
+        field = np.clip(field, vs.min(), vs.max())
+        if self._shape == "round":
+            alpha = ellipse_alpha(*field.shape)
+        else:
+            alpha = np.ones(field.shape)
+        grid_img = self._field_to_qimage(field, alpha)
+        self._heatmap = grid_img.scaled(
+            ds, ds,
+            Qt.AspectRatioMode.IgnoreAspectRatio,
+            Qt.TransformationMode.SmoothTransformation,
+        )
 
-    def _field_to_qimage(self, field: np.ndarray, ds: int) -> QImage:
-        """Apply a band-aware tri-color gradient → RGBA QImage."""
+    def _field_to_qimage(self, field: np.ndarray, alpha: np.ndarray) -> QImage:
+        """Apply a band-aware tri-color gradient → RGBA QImage at the field's own resolution."""
         lo_b = self._target - self._margin
         hi_b = self._target + self._margin
         span = hi_b - lo_b or 1.0
@@ -428,19 +628,28 @@ class WaferMapItem(QQuickPaintedItem):
             lo_c * (1 - t_lo) + mid_c * t_lo,
             mid_c * (1 - t_hi) + hi_c * t_hi,
         )
-        # Outside the wafer circle `field` is NaN → NaN propagates into rgb. Alpha
-        # masks those pixels anyway, but zero them so the uint8 cast is well-defined.
         rgb = np.nan_to_num(rgb, nan=0.0)
-        rgba = np.zeros((ds, ds, 4), dtype=np.uint8)
+        gh, gw = field.shape
+        rgba = np.zeros((gh, gw, 4), dtype=np.uint8)
         rgba[:, :, :3] = (rgb * 255).astype(np.uint8)
-        rgba[:, :, 3]  = np.where(np.isfinite(field), 210, 0).astype(np.uint8)
+        # alpha is a continuous 0..1 coverage mask (not a hard isfinite cutoff) so the
+        # round-clip boundary anti-aliases instead of showing coarse-grid steps.
+        rgba[:, :, 3]  = (alpha * 210).astype(np.uint8)
 
-        return QImage(rgba.tobytes(), ds, ds, QImage.Format.Format_RGBA8888).copy()
+        return QImage(rgba.tobytes(), gw, gh, QImage.Format.Format_RGBA8888).copy()
 
     # ── paint ─────────────────────────────────────────────────────────────
 
     def paint(self, painter: QPainter) -> None:
-        ds   = self._draw_size()
+        ds = self._draw_size()
+        if ds != self._last_draw_size:
+            # Geometry settled (or changed) since markers/heatmap were last built
+            # against a stale size — recompute now, at actual paint time.
+            self._last_draw_size = ds
+            self._compute_markers()
+            self._rebuild_heatmap()
+            self._rebuild_thickness()
+
         r_px = int(ds / 2 - 4)
         cx, cy = self._center()
 
@@ -461,6 +670,7 @@ class WaferMapItem(QQuickPaintedItem):
             painter.setOpacity(1.0)
 
         self._paint_markers(painter)
+        self._paint_extremes(painter)
 
     def _paint_template(self, painter: QPainter, cx: int, cy: int, r_px: int) -> None:
         ds = self._draw_size()
@@ -524,11 +734,11 @@ class WaferMapItem(QQuickPaintedItem):
             font_scale = 0.85
 
         id_font = QFont()
-        id_font.setPointSize(max(4, int(r * font_scale)))
+        id_font.setPointSize(max(9, int(r * font_scale)))
         id_font.setBold(True)
 
         temp_font = QFont()
-        temp_font.setPointSize(max(3, int((r - 1) * font_scale)))
+        temp_font.setPointSize(max(9, int(r * font_scale)))
 
         band_color = {
             "in_range": self._in_range_color,
@@ -536,6 +746,16 @@ class WaferMapItem(QQuickPaintedItem):
             "low":      self._low_color,
         }
 
+        painter.setFont(id_font)
+        id_fm = painter.fontMetrics()
+        id_line_h = id_fm.height()
+        id_ascent = id_fm.ascent()
+
+        painter.setFont(temp_font)
+        temp_fm = painter.fontMetrics()
+        temp_line_h = temp_fm.height()
+        temp_ascent = temp_fm.ascent()
+
         for i, s in enumerate(self._sensors):
             if i not in self._markers:
                 continue
@@ -544,10 +764,22 @@ class WaferMapItem(QQuickPaintedItem):
                 self._bands[i] if i < len(self._bands) else "in_range",
                 self._in_range_color,
             )
+            is_hovered = i == self._hovered_index
+            marker_r = int(round(r * self._hover_scale)) if is_hovered else r
+
+            if is_hovered:
+                # Soft glow ring behind the marker, growing with hoverScale.
+                glow_r = int(round(marker_r * 1.9))
+                glow_color = QColor(color)
+                glow_color.setAlpha(70)
+                painter.setPen(Qt.PenStyle.NoPen)
+                painter.setBrush(QBrush(glow_color))
+                painter.drawEllipse(px - glow_r, py - glow_r, 2 * glow_r, 2 * glow_r)
+
             # Filled circle with thin dark outline for contrast over heatmap
             painter.setPen(QPen(QColor(0, 0, 0, 100), 1))
             painter.setBrush(QBrush(color))
-            painter.drawEllipse(px - r, py - r, 2 * r, 2 * r)
+            painter.drawEllipse(px - marker_r, py - marker_r, 2 * marker_r, 2 * marker_r)
 
             if self._show_labels:
                 has_temp = i < len(self._values)
@@ -557,17 +789,6 @@ class WaferMapItem(QQuickPaintedItem):
                 ox = getattr(s, "offset_x", 0.0) * r
                 oy = getattr(s, "offset_y", 0.0) * r
 
-                # Pre-compute metrics using current scaled fonts
-                painter.setFont(id_font)
-                id_fm = painter.fontMetrics()
-                id_line_h = id_fm.height()
-                id_ascent = id_fm.ascent()
-
-                painter.setFont(temp_font)
-                temp_fm = painter.fontMetrics()
-                temp_line_h = temp_fm.height()
-                temp_ascent = temp_fm.ascent()
-
                 id_text = s.label
                 temp_text = f"{self._values[i]:.2f}" if has_temp else ""
 
@@ -598,11 +819,11 @@ class WaferMapItem(QQuickPaintedItem):
                 painter.setPen(QPen(self._text_color))
                 y1 = ly + id_ascent
                 if side in ("top", "bottom"):
-                    painter.drawText(lx + (text_w - id_w) // 2, y1, id_text)
+                    painter.drawText(lx + (text_w - id_w) // 2, y1, id_text)  # type: ignore[arg-type]
                 elif side == "left":
-                    painter.drawText(lx + (text_w - id_w), y1, id_text)
+                    painter.drawText(lx + (text_w - id_w), y1, id_text)  # type: ignore[arg-type]
                 else:
-                    painter.drawText(lx, y1, id_text)
+                    painter.drawText(lx, y1, id_text)  # type: ignore[arg-type]
 
                 # Draw Temperature (second line)
                 if has_temp:
@@ -610,8 +831,8 @@ class WaferMapItem(QQuickPaintedItem):
                     painter.setPen(QPen(color))
                     y2 = ly + id_line_h + temp_ascent
                     if side in ("top", "bottom"):
-                        painter.drawText(lx + (text_w - temp_w) // 2, y2, temp_text)
+                        painter.drawText(lx + (text_w - temp_w) // 2, y2, temp_text)  # type: ignore[arg-type]
                     elif side == "left":
-                        painter.drawText(lx + (text_w - temp_w), y2, temp_text)
+                        painter.drawText(lx + (text_w - temp_w), y2, temp_text)  # type: ignore[arg-type]
                     else:
-                        painter.drawText(lx, y2, temp_text)
+                        painter.drawText(lx, y2, temp_text)  # type: ignore[arg-type]

src/pygui/backend/wafer/__init__.py

@@ -1,10 +0,0 @@
-# ===== Wafer Sub-package =====
-from pygui.backend.wafer.wafer_layouts import available_families, load_layout
-from pygui.backend.wafer.zwafer_models import DataRecord, Sensor, ZWaferData
-from pygui.backend.wafer.zwafer_parser import ZWaferParser
-
-__all__ = [
-    "ZWaferData", "Sensor", "DataRecord",
-    "ZWaferParser",
-    "load_layout", "available_families",
-]

src/pygui/backend/wafer/family_spec.py

@@ -0,0 +1,9 @@
+"""Single source of truth for the wafer sensor-count partition."""
+
+
+def sensor_count_for(family_code: str) -> int:
+    """Return the number of valid sensor readings for a wafer family code.
+
+    Returns 80 for the "X" family. Returns 244 for every other family
+    code."""
+    return 80 if family_code == "X" else 244

src/pygui/backend/wafer/wafer_layouts.py

@@ -66,9 +66,39 @@ def _family_name(raw_name: str) -> str:
 
 def _load_yaml(path: Path) -> dict:
     with path.open(encoding="utf-8") as f:
-        return yaml.safe_load(f)
+        loaded: dict = yaml.safe_load(f)
+        return loaded
 
 
+# Edge→center sensor pair tables, ported verbatim from the C# original
+# (Form1.cs ec_map_*). Indices are 0-origin. Domain data, not derivable from
+# ring geometry — see docs/adr/0002-edge-center-pair-tables.md.
+_EC_MAPS: dict[str, tuple[tuple[int, int], ...]] = {
+    "AEP": tuple((e, 40 + e // 2) for e in range(16)),
+    "BCD": tuple((e, 28) for e in range(12)),
+    "F": ((0, 18), (1, 19), (2, 19), (3, 19), (4, 20), (5, 20),
+          (6, 20), (7, 21), (8, 21), (9, 21), (10, 18), (11, 18)),
+    "X": ((5, 76), (0, 76), (39, 76), (6, 77), (11, 77), (16, 77),
+          (17, 78), (22, 78), (27, 78), (28, 79), (33, 79), (38, 79)),
+    "Z": tuple((e, 0) for e in range(49, 65)),
+}
+
+
+def ec_pairs_for_wafer_id(wafer_id: str) -> tuple[tuple[int, int], ...]:
+    """Edge-center pairs for a wafer id's family letter; empty if unknown.
+
+    Unknown families deliberately get no pairs (C# fell through to Z).
+    """
+    prefix = wafer_id[0].upper() if wafer_id else ""
+    for families, key in (("AEP", "AEP"), ("BCD", "BCD"), ("F", "F"),
+                          ("X", "X"), ("Z", "Z")):
+        if prefix and prefix in families:
+            return _EC_MAPS[key]
+    return ()
+
+
+# P6.3 (LayoutSelector) dropped 2026-07-10 — the C# "layout" buttons only
+# exported coordinate spreadsheets, decided obsolete. See MIGRATION.md.
 def available_families() -> list[str]:
     return [_family_name(_load_yaml(p)["name"]) for p in _LAYOUTS_DIR.glob("*.yaml")]
 

src/pygui/backend/wafer/zwafer_parser.py

@@ -104,9 +104,6 @@ class ZWaferParser:
             elif key.lower() == "wafer id":
                 wafer_data.serial = value
 
-        if found_kv and wafer_data.date == datetime.min:
-            wafer_data.date = datetime.min
-
         return found_kv
 
     # ===== Sensor Layout Parsing =====
@@ -118,7 +115,7 @@ class ZWaferParser:
         y_coords: Optional[list],
     ) -> None:
         """Build sensor list from layout arrays."""
-        if not all([labels, x_coords, y_coords]):
+        if not (labels and x_coords and y_coords):
             raise ValueError("Sensor layout section is incomplete or missing.")
 
         if len(labels) != len(x_coords) or len(labels) != len(y_coords):

src/pygui/serialcomm/data_parser.py

@@ -10,15 +10,12 @@ Mirrors the C# Form1.cs binary parsing pipeline:
 
 import logging
 import os
+from datetime import datetime
 from typing import Optional
 
-log = logging.getLogger(__name__)
+from pygui.backend.wafer.family_spec import sensor_count_for
 
-# Max DUTs (sensors) per row before overhead bytes are stripped
-# P wafer: 244 valid readings per 256-block (12 overhead bytes)
-# X wafer: 80 valid readings per 256-block (14 overhead bytes)
-MAXDUT_P = 244
-MAXDUT_X = 80
+log = logging.getLogger(__name__)
 
 
 def csv_column_count(family_code: str) -> int:
@@ -110,6 +107,23 @@ def _convert_aep(binary_bits: list[int]) -> float:
     return result
 
 
+def _convert_debug_temp(hex_str: str) -> float:
+    """Convert a 4-char hex string to a debug/cold-junction temperature.
+
+    Mirrors C#'s ConvertBinaryArrayToDebugTemp: bits 4-14 scaled by
+    2**(i-8), sign bit at bit 0. No family-code branching — this formula
+    applies regardless of wafer family, unlike _convert_hex_to_temp.
+    """
+    bits = _hex_to_binary(hex_str)
+    value = 0.0
+    for i in range(4, 15):
+        if bits[i]:
+            value += 2.0 ** (i - 8)
+    if bits[0]:
+        value = -value
+    return round(value, 2)
+
+
 def _convert_hex_to_temp(hex_str: str, family_code: str) -> float:
     """Convert a singi hale 4-char hex string to a float temperature."""
     bits = _hex_to_binary(hex_str)
@@ -156,26 +170,27 @@ def _parse_p_binary(data_bytes: bytes) -> list[list[str]]:
     """Parse P-family (and A/B/C/D/E/F) binary data.
 
     Each block of 256 readings has 244 valid + 12 overhead.
-    Valid readings are chunked into rows of MAXDUT_P (244).
+    Valid readings are chunked into rows of the family's sensor count (244).
     """
+    sensor_count = sensor_count_for("P")
     readings: list[str] = []
 
     # Read 2 bytes at a time (UInt16 little-endian)
-    # Each 256-word block has MAXDUT_P valid readings (first N words), rest are overhead
+    # Each 256-word block has `sensor_count` valid readings (first N words), rest are overhead
     num_words = len(data_bytes) // 2
     for i in range(num_words):
         value = int.from_bytes(data_bytes[i * 2 : i * 2 + 2], byteorder="little")
-        if i % 256 < MAXDUT_P:
+        if i % 256 < sensor_count:
             readings.append(f"{value:04X}")
 
-    # Chunk into rows of MAXDUT_P
+    # Chunk into rows of sensor_count
     result: list[list[str]] = []
     idx = 0
-    while idx + MAXDUT_P <= len(readings):
-        result.append(readings[idx : idx + MAXDUT_P])
-        idx += MAXDUT_P
+    while idx + sensor_count <= len(readings):
+        result.append(readings[idx : idx + sensor_count])
+        idx += sensor_count
 
-    log.info("Parsed P-family: %d rows × %d cols", len(result), MAXDUT_P)
+    log.info("Parsed P-family: %d rows × %d cols", len(result), sensor_count)
     return result
 
 
@@ -183,24 +198,25 @@ def _parse_x_binary(data_bytes: bytes) -> list[list[str]]:
     """Parse X-family binary data.
 
     Each block of 256 readings has 80 valid + 14 overhead.
-    Valid readings are chunked into rows of MAXDUT_X (80).
+    Valid readings are chunked into rows of the family's sensor count (80).
     """
+    sensor_count = sensor_count_for("X")
     readings: list[str] = []
 
     num_words = len(data_bytes) // 2
     for i in range(num_words):
         value = int.from_bytes(data_bytes[i * 2 : i * 2 + 2], byteorder="little")
-        if i % 256 < MAXDUT_X:
+        if i % 256 < sensor_count:
             readings.append(f"{value:04X}")
 
-    # Chunk into rows of MAXDUT_X
+    # Chunk into rows of sensor_count
     result: list[list[str]] = []
     idx = 0
-    while idx + MAXDUT_X <= len(readings):
-        result.append(readings[idx : idx + MAXDUT_X])
-        idx += MAXDUT_X
+    while idx + sensor_count <= len(readings):
+        result.append(readings[idx : idx + sensor_count])
+        idx += sensor_count
 
-    log.info("Parsed X-family: %d rows × %d cols", len(result), MAXDUT_X)
+    log.info("Parsed X-family: %d rows × %d cols", len(result), sensor_count)
     return result
 
 
@@ -226,6 +242,15 @@ def convert_to_temperatures(
     return temp_value
 
 
+def convert_to_debug_temperatures(hex_data: list[list[str]]) -> list[list[str]]:
+    """Convert debug/cold-junction hex values to temperature strings.
+
+    Same shape contract as convert_to_temperatures, but uses the
+    family-independent debug formula (_convert_debug_temp).
+    """
+    return [[str(_convert_debug_temp(h)) for h in row] for row in hex_data]
+
+
 def remove_trailing_zeros(data: list[list[str]]) -> None:
     """Remove rows of all-zero values from the end of data (in-place).
 
@@ -239,7 +264,7 @@ def remove_trailing_zeros(data: list[list[str]]) -> None:
                 fval = float(val)
             except ValueError:
                 fval = 99.9
-            if fval >= 0.01:
+            if abs(fval) >= 0.01:
                 is_all_zero = False
                 break
         if is_all_zero:
@@ -268,13 +293,18 @@ def save_to_csv(
     try:
         os.makedirs(output_dir, exist_ok=True)
         # Build filename: P00001-20260505_133045.csv
-        from datetime import datetime
 
         timestamp = datetime.now().strftime("%Y%m%d_%H%M%S")
         filename = f"{serial_number}-{timestamp}.csv"
         filepath = os.path.join(output_dir, filename)
 
-        num_cols = csv_column_count(family_code)
+        # Header count = max of display column count and actual data width.
+        # csv_column_count gives the display sensor count (e.g. 48 for P),
+        # but the binary parser may yield more readings (244 for P). Use the
+        # actual data width so no sensor values are silently dropped.
+        display_cols = csv_column_count(family_code)
+        data_width = max((len(r) for r in data), default=0)
+        num_cols = max(display_cols, data_width)
         with open(filepath, "w", encoding="utf-8") as f:
             # Header row: Sensor1,Sensor2,...
             headers = [f"Sensor{j + 1}" for j in range(num_cols)]
@@ -290,3 +320,46 @@ def save_to_csv(
     except Exception as exc:
         log.error("CSV save failed: %s", exc)
         return None
+
+
+def save_debug_csv(
+    temp_data: list[list[str]],
+    debug_data: list[list[str]],
+    output_dir: str,
+) -> Optional[str]:
+    """Save sensor + debug temperatures side-by-side to debug_info.csv.
+
+    Mirrors C#'s writeDebugCSV: alternating Sensor{j+1},Debug{j+1} columns,
+    truncated to the shorter of the two row/column counts. Fixed filename
+    (not timestamped), unlike save_to_csv.
+
+    Args:
+        temp_data: 2D array of sensor temperature strings (D1, decoded via
+            convert_to_temperatures).
+        debug_data: 2D array of debug temperature strings (F1, decoded via
+            convert_to_debug_temperatures).
+        output_dir: Directory to save the CSV file.
+
+    Returns:
+        Full file path on success, None on empty input or write failure.
+    """
+    if not temp_data or not debug_data:
+        log.error("Debug CSV save failed: temp or debug data is empty")
+        return None
+    try:
+        os.makedirs(output_dir, exist_ok=True)
+        num_cols = min(len(temp_data[0]), len(debug_data[0]))
+        num_rows = min(len(temp_data), len(debug_data))
+        filepath = os.path.join(output_dir, "debug_info.csv")
+        with open(filepath, "w", encoding="utf-8") as f:
+            headers = [f"Sensor{j + 1},Debug{j + 1}" for j in range(num_cols)]
+            f.write(",".join(headers) + "\n")
+            for i in range(num_rows):
+                row = [f"{temp_data[i][j]},{debug_data[i][j]}" for j in range(num_cols)]
+                f.write(",".join(row) + "\n")
+
+        log.info("Saved debug CSV: %d rows × %d cols to %s", num_rows, num_cols, filepath)
+        return filepath
+    except Exception as exc:
+        log.error("Debug CSV save failed: %s", exc)
+        return None

src/pygui/serialcomm/device_service.py

@@ -19,16 +19,14 @@ log = logging.getLogger(__name__)
 class DeviceService:
     """High-level wafer device communication."""
 
-    # Expected hex string lengths for known wafer families
-    # P wafer: 393216 hex chars (196608 bytes)
-    # X wafer: 1310720 hex chars (655360 bytes)
-    EXPECTED_HEX_LENGTHS = {
-        "P": 393216,
-        "X": 1310720,
-    }
-
     def __init__(self, settings: LocalSettings) -> None:
         self._settings = settings
+        self._cached_ports: list[str] = []
+        self._last_port_scan_time = 0.0
+
+    def clear_port_scan_cache(self) -> None:
+        """Force the next scan to bypass the cache."""
+        self._last_port_scan_time = 0.0
 
     # ------------------------------------------------------------------
     # Public API
@@ -36,6 +34,11 @@ class DeviceService:
 
     def enumerate_ports(self) -> list[str]:
         """Return list of available serial port names."""
+        import time
+        now = time.monotonic()
+        if now - self._last_port_scan_time < 2.0:
+            return self._cached_ports
+
         hardware_ports = [p.device for p in serial.tools.list_ports.comports()]
         virtual_ports = []
 
@@ -86,6 +89,8 @@ class DeviceService:
             if p not in ordered_ports:
                 ordered_ports.append(p)
 
+        self._cached_ports = ordered_ports
+        self._last_port_scan_time = time.monotonic()
         return ordered_ports
 
 
@@ -196,7 +201,3 @@ class DeviceService:
         except Exception as exc:
             log.error("Erase failed on %s: %s", port, exc)
             return False
-
-    def get_expected_hex_length(self, family_code: str) -> int:
-        """Return expected hex string length for a wafer family."""
-        return self._settings.get_wafer_data_size(family_code)

src/pygui/serialcomm/serial_port.py

@@ -65,6 +65,10 @@ class SerialPort:
         )
         if timeout is not None:
             kwargs["timeout"] = timeout
+        # Write timeout must never be None (= block forever): on macOS,
+        # pseudo-ports like Bluetooth-Incoming-Port accept the open and then
+        # hang the write, which froze detect in "Detecting..." permanently.
+        kwargs["write_timeout"] = timeout if timeout is not None else 2.0
 
         try:
             return pyserial.Serial(port_name, SerialPort.BAUDRATE, **kwargs)

src/pygui/serialcomm/stream_reader.py

@@ -7,12 +7,16 @@ import time
 from typing import Callable
 
 from pygui.backend.models.frame import Frame
+from pygui.backend.wafer.family_spec import sensor_count_for
 from pygui.serialcomm.data_parser import _convert_hex_to_temp
 
 log = logging.getLogger(__name__)
 
 ParseFrame = Callable[[bytes, int], Frame]
 
+# Max consecutive resync attempts before giving up on a corrupt stream.
+_MAX_RESYNC_ATTEMPTS = 50
+
 class StreamReader:
 
     def __init__(self, transport, parse_frame: ParseFrame,
@@ -27,6 +31,8 @@ class StreamReader:
         self._thread: threading.Thread | None = None
         self._stop = threading.Event()
         self.error_count = 0
+        # Cumulative count of resync events (lost sync marker) for stream stats.
+        self.resync_count = 0
 
     def start(self) -> None:
         self._stop.clear()
@@ -36,17 +42,13 @@ class StreamReader:
     def _read_chunk(self, min_bytes: int = 1) -> bytes:
         """Read a chunk of available bytes from the transport.
 
-        Reads up to 256 bytes in one shot instead of byte-at-a-time,
-        falling back to single-byte reads with a yield when nothing is
-        immediately available."""
-        chunk = self._transport.read(max(min_bytes, 256))
-        if chunk:
-            return chunk
-        # Nothing available right now – yield briefly to avoid busy-spin.
-        b = self._transport.read(1)
-        if not b:
+        Reads up to 256 bytes in one shot. If nothing is immediately
+        available, yields briefly to avoid a busy spin.
+        """
+        chunk: bytes = self._transport.read(max(min_bytes, 256))
+        if not chunk:
             time.sleep(0.005)
-        return b
+        return chunk
 
     def _accumulate(self, needed: int) -> bytearray:
         """Accumulate *needed* bytes using buffered reads."""
@@ -92,15 +94,22 @@ class StreamReader:
 
             # Default: ASCII hex dump stream.
             self._run_ascii(raw)
+        except Exception as exc:
+            log.exception("StreamReader thread encountered error: %s", exc)
+            try:
+                self._on_error(exc)
+            except Exception:
+                pass
         finally:
             try:
                 self._transport.close()
             except Exception:
                 pass
 
-    def _run_binary(self, initial_bytes: bytes) -> None:
+    def _run_binary(self, initial_bytes: bytes | bytearray) -> None:
         log.info("StreamReader: starting binary stream parsing")
         buf = bytearray(initial_bytes)
+        resync_attempts = 0
 
         while not self._stop.is_set():
             # Find sync marker in buffer.
@@ -113,6 +122,7 @@ class StreamReader:
                 idx += 1
 
             if synced:
+                resync_attempts = 0
                 buf = buf[idx:]
                 # Accumulate header (5 bytes after sync).
                 while len(buf) < 7 and not self._stop.is_set():
@@ -139,7 +149,7 @@ class StreamReader:
                 payload = buf[7:7 + payload_len]
 
                 try:
-                    frame = self._parse(payload, seq)
+                    frame = self._parse(payload, seq)  # type: ignore[arg-type]
                     self._on_frame(frame)
                 except Exception as exc:
                     self.error_count += 1
@@ -150,6 +160,18 @@ class StreamReader:
                 buf = buf[total_packet_len:]
             else:
                 # Resync: keep only trailing 0xAA if present, then read more.
+                resync_attempts += 1
+                self.resync_count += 1
+                if resync_attempts > _MAX_RESYNC_ATTEMPTS:
+                    log.error(
+                        "StreamReader: giving up after %d resync attempts "
+                        "(no 0xAA 0x88 sync marker found in stream)",
+                        resync_attempts,
+                    )
+                    self._on_error(
+                        TimeoutError("Binary stream resync failed: no sync marker")
+                    )
+                    return
                 if len(buf) > 0 and buf[-1] == 0xAA:
                     buf = bytearray([0xAA])
                 else:
@@ -161,7 +183,7 @@ class StreamReader:
     def _run_ascii(self, initial_bytes: bytes) -> None:
         log.info("StreamReader: starting ASCII hex dump stream parsing")
 
-        valid_words = 80 if self._family_code == "X" else 244
+        valid_words = sensor_count_for(self._family_code)
         block_words = 256
         word_char_len = 4
         chars_needed = block_words * word_char_len  # total hex chars per block
@@ -216,7 +238,7 @@ class StreamReader:
             for hex_val in valid_hex_words:
                 try:
                     swapped = hex_val[2:4] + hex_val[0:2]
-                    t = _convert_hex_to_temp(swapped, self._family_code)
+                    t = _convert_hex_to_temp(swapped, self._family_code)  # type: ignore[arg-type]
                     values.append(t)
                 except Exception:
                     values.append(0.0)
@@ -240,7 +262,7 @@ class StreamReader:
                 line = line_bytes.decode('utf-8', errors='ignore').strip()
                 if line:
                     try:
-                        frame = self._parse(line, seq)
+                        frame = self._parse(line, seq)  # type: ignore[arg-type]
                         if frame:
                             self._on_frame(frame)
                             seq += 1

tests/fixtures/sample_stream_b.csv

@@ -0,0 +1,11 @@
+Wafer ID=A12
+Acquisition Date=03/26/2025
+Label,1,2,3
+X (mm),0,10,-10
+Y (mm),10,-10,-10
+data
+0.0,150.0,149.5,151.6
+0.5,150.2,149.4,151.7
+1.0,150.1,149.6,151.5
+1.5,150.3,149.7,151.4
+2.0,150.4,149.8,151.3

tests/test_chart_geometry.py

@@ -0,0 +1,52 @@
+import pytest
+
+from pygui.backend.visualization.chart_geometry import (
+    elapsed_to_pixel,
+    index_to_pixel,
+    value_to_pixel,
+)
+
+
+def test_value_to_pixel_min_maps_to_bottom():
+    assert value_to_pixel(0.0, 0.0, 100.0, pixel_start=10.0, pixel_span=200.0) == pytest.approx(210.0)
+
+
+def test_value_to_pixel_max_maps_to_top():
+    assert value_to_pixel(100.0, 0.0, 100.0, pixel_start=10.0, pixel_span=200.0) == pytest.approx(10.0)
+
+
+def test_value_to_pixel_midpoint():
+    assert value_to_pixel(50.0, 0.0, 100.0, pixel_start=0.0, pixel_span=200.0) == pytest.approx(100.0)
+
+
+def test_value_to_pixel_degenerate_range_centers():
+    assert value_to_pixel(5.0, 5.0, 5.0, pixel_start=0.0, pixel_span=200.0) == pytest.approx(100.0)
+
+
+def test_index_to_pixel_first_and_last():
+    assert index_to_pixel(0, 5, pixel_start=0.0, pixel_span=100.0) == pytest.approx(0.0)
+    assert index_to_pixel(4, 5, pixel_start=0.0, pixel_span=100.0) == pytest.approx(100.0)
+
+
+def test_index_to_pixel_single_point_centers():
+    assert index_to_pixel(0, 1, pixel_start=0.0, pixel_span=100.0) == pytest.approx(50.0)
+
+
+def test_elapsed_to_pixel_window_start_maps_to_left():
+    assert elapsed_to_pixel(10.0, window_start=10.0, window_end=70.0,
+                             pixel_start=0.0, pixel_span=200.0) == pytest.approx(0.0)
+
+
+def test_elapsed_to_pixel_window_end_maps_to_right():
+    assert elapsed_to_pixel(70.0, window_start=10.0, window_end=70.0,
+                             pixel_start=0.0, pixel_span=200.0) == pytest.approx(200.0)
+
+
+def test_elapsed_to_pixel_midpoint():
+    assert elapsed_to_pixel(40.0, window_start=10.0, window_end=70.0,
+                             pixel_start=0.0, pixel_span=200.0) == pytest.approx(100.0)
+
+
+def test_elapsed_to_pixel_degenerate_window_pins_right():
+    assert elapsed_to_pixel(5.0, window_start=5.0, window_end=5.0,
+                             pixel_start=0.0, pixel_span=200.0) == pytest.approx(200.0)

tests/test_cluster_average.py

@@ -1,6 +1,6 @@
 """Tests for src/pygui/backend/cluster_average.py."""
 import math
-import pytest
+
 from pygui.backend.cluster_average import average_clusters, group_sensors_by_radius
 from pygui.backend.wafer.zwafer_models import Sensor
 

tests/test_comparison.py

@@ -1,6 +1,5 @@
 """Tests for src/pygui/backend/comparison.py."""
 
-import numpy as np
 from pygui.backend.comparison import compare_runs
 
 

tests/test_csv_recorder.py

@@ -37,4 +37,71 @@ def test_recorded_data_rows_are_readable(tmp_path):
     assert records[0].time == 0.0
     assert records[0].values == [149.0, 148.0]
     assert records[1].time == 0.5
-    assert records[1].values == [149.5, 148.5]
+    assert records[1].values == [149.5, 148.5]
+
+# ===== write_segment (P3.3) =====
+def _make_zwafer_csv(tmp_path, rows=5):
+    sensors = [Sensor("1", 0.0, 1.0), Sensor("2", 1.0, 0.0)]
+    path = tmp_path / "src.csv"
+    rec = CsvRecorder()
+    rec.start(str(path), sensors, serial="A12")
+    for i in range(rows):
+        rec.write(Frame(seq=i, time=i * 0.5, values=[100.0 + i, 200.0 + i]))
+    rec.stop()
+    return path
+
+
+def test_write_segment_zwafer_slice(tmp_path):
+    src = _make_zwafer_csv(tmp_path, rows=5)
+    dest = tmp_path / "seg.csv"
+    assert CsvRecorder.write_segment(str(dest), str(src), 1, 3) is True
+
+    records = read_data_records(str(dest))
+    assert len(records) == 3
+    assert records[0].values == [101.0, 201.0]
+    assert records[-1].values == [103.0, 203.0]
+
+    # header survives → still parses as a wafer CSV
+    data, _ = ZWaferParser().parse(str(dest))
+    assert data is not None
+    assert [s.label for s in data.sensors] == ["1", "2"]
+
+
+def test_write_segment_full_range(tmp_path):
+    src = _make_zwafer_csv(tmp_path, rows=4)
+    dest = tmp_path / "seg.csv"
+    assert CsvRecorder.write_segment(str(dest), str(src), 0, 3) is True
+    assert len(read_data_records(str(dest))) == 4
+
+
+def test_write_segment_out_of_range(tmp_path):
+    src = _make_zwafer_csv(tmp_path, rows=3)
+    dest = tmp_path / "seg.csv"
+    assert CsvRecorder.write_segment(str(dest), str(src), 10, 20) is False
+    assert not dest.exists()
+
+
+def test_write_segment_invalid_range(tmp_path):
+    src = _make_zwafer_csv(tmp_path, rows=3)
+    dest = tmp_path / "seg.csv"
+    assert CsvRecorder.write_segment(str(dest), str(src), 2, 1) is False
+    assert CsvRecorder.write_segment(str(dest), str(src), -1, 1) is False
+
+
+def test_write_segment_official_csv(tmp_path):
+    # official format: row 0 = sensor names, rows 1+ = values only
+    src = tmp_path / "A00001-x.csv"
+    src.write_text(
+        "Sensor1,Sensor2\n"
+        "10.0,20.0\n"
+        "11.0,21.0\n"
+        "12.0,22.0\n",
+        encoding="utf-8",
+    )
+    dest = tmp_path / "A00001-x_seg.csv"
+    assert CsvRecorder.write_segment(str(dest), str(src), 1, 2) is True
+    lines = dest.read_text(encoding="utf-8").splitlines()
+    assert lines[0] == "Sensor1,Sensor2"
+    assert lines[1] == "11.0,21.0"
+    assert lines[2] == "12.0,22.0"
+    assert len(lines) == 3

tests/test_data_parser.py

@@ -1,15 +1,17 @@
 """Tests for serialcomm/data_parser.py binary parsing pipeline."""
 
 import pytest
+
 from pygui.serialcomm.data_parser import (
+    _convert_debug_temp,
+    _convert_hex_to_temp,
+    convert_to_debug_temperatures,
+    convert_to_temperatures,
     csv_column_count,
     parse_binary_data,
-    convert_to_temperatures,
     remove_trailing_zeros,
+    save_debug_csv,
     save_to_csv,
-    _convert_hex_to_temp,
-    MAXDUT_P,
-    MAXDUT_X,
 )
 
 # ── csv_column_count ──────────────────────────────────────────────────────────
@@ -106,7 +108,7 @@ def _make_p_block(num_blocks: int = 1, value: int = 0x0100) -> bytes:
     data = bytearray()
     for _ in range(num_blocks):
         for i in range(256):
-            word = value if i < MAXDUT_P else 0
+            word = value if i < 244 else 0
             data += word.to_bytes(2, byteorder="little")
     return bytes(data)
 
@@ -120,7 +122,7 @@ def _make_x_block(num_blocks: int = 1, value: int = 0x0100) -> bytes:
     data = bytearray()
     for _ in range(num_blocks):
         for i in range(256):
-            word = value if i < MAXDUT_X else 0
+            word = value if i < 80 else 0
             data += word.to_bytes(2, byteorder="little")
     return bytes(data)
 
@@ -136,7 +138,7 @@ class TestParseBinaryData:
         data = _make_p_block(1)
         result = parse_binary_data(data, "P")
         assert result is not None
-        assert len(result[0]) == MAXDUT_P  # 244
+        assert len(result[0]) == 244
 
     def test_p_family_two_blocks_returns_two_rows(self):
         data = _make_p_block(2)
@@ -161,14 +163,14 @@ class TestParseBinaryData:
         data = _make_x_block(1)
         result = parse_binary_data(data, "X")
         assert result is not None
-        assert len(result[0]) == MAXDUT_X  # 80
+        assert len(result[0]) == 80
 
     def test_a_family_uses_p_parser(self):
         # A/B/C/D/E/F all route to _parse_p_binary
         data = _make_p_block(1)
         result = parse_binary_data(data, "A")
         assert result is not None
-        assert len(result[0]) == MAXDUT_P
+        assert len(result[0]) == 244
 
     def test_empty_bytes_returns_empty_list(self):
         result = parse_binary_data(b"", "P")
@@ -242,6 +244,11 @@ class TestRemoveTrailingZeros:
         remove_trailing_zeros(data)
         assert len(data) == 2
 
+    def test_preserves_negative_temperatures(self):
+        data = [["25.0", "24.5"], ["-5.5", "-10.0"]]
+        remove_trailing_zeros(data)
+        assert len(data) == 2
+
 
 # ── save_to_csv ───────────────────────────────────────────────────────────────
 
@@ -261,20 +268,25 @@ class TestSaveToCsv:
         assert result is not None
         assert "P12345" in result
 
-    def test_csv_has_sensor_headers(self, tmp_path):
-        # Header count is driven by csv_column_count(family), not data width.
-        # P family → 48 sensors; F family → 22 sensors; X family → 80 sensors.
-        cases = [("P", 48), ("F", 22), ("X", 80), ("B", 29)]
-        for family, expected_cols in cases:
-            data = [["25.0", "24.5"]]
-            result = save_to_csv(data, family, f"{family}00001", str(tmp_path))
-            assert result is not None, f"save_to_csv returned None for {family}"
-            headers = open(result).readline().strip().split(",")
-            assert (
-                len(headers) == expected_cols
-            ), f"{family}: expected {expected_cols} headers, got {len(headers)}"
-            assert headers[0] == "Sensor1"
-            assert headers[-1] == f"Sensor{expected_cols}"
+    def test_csv_header_wins_when_data_wider_than_display(self, tmp_path):
+        # Header count = max(csv_column_count, data width).
+        # When data has 60 columns and P display is 48, header is 60 — no truncation.
+        data = [[f"{i}.0" for i in range(60)]]
+        result = save_to_csv(data, "P", "P00001", str(tmp_path))
+        assert result is not None
+        headers = open(result).readline().strip().split(",")
+        assert len(headers) == 60, "data width 60 should win over display 48"
+        assert headers[0] == "Sensor1"
+        assert headers[-1] == "Sensor60"
+
+    def test_csv_uses_display_count_when_data_is_narrower(self, tmp_path):
+        # When data has fewer columns than the display count, pad to display.
+        data = [["25.0"]]
+        result = save_to_csv(data, "X", "X00001", str(tmp_path))
+        assert result is not None
+        headers = open(result).readline().strip().split(",")
+        # X display = 80, data = 1 → headers = 80
+        assert len(headers) == 80
 
     def test_csv_row_count_matches_data(self, tmp_path):
         data = [["25.0"], ["24.5"], ["23.0"]]
@@ -297,3 +309,112 @@ class TestSaveToCsv:
         data = [["25.0"]]
         result = save_to_csv(data, "P", "P00001", "/\x00invalid\x00path")
         assert result is None
+
+    def test_preserves_all_columns_when_data_wider_than_display(self, tmp_path):
+        # Bug fix: when data has more columns than csv_column_count(family),
+        # all data columns must be preserved (no silent truncation).
+        data = [[f"{i}.0" for i in range(244)]]
+        result = save_to_csv(data, "P", "P00001", str(tmp_path))
+        assert result is not None
+        with open(result) as f:
+            lines = f.readlines()
+        headers = lines[0].strip().split(",")
+        data_row = lines[1].strip().split(",")
+        # All 244 columns should be preserved, not truncated to 48
+        assert len(headers) == 244, f"expected 244 cols, got {len(headers)}"
+        assert len(data_row) == 244, f"expected 244 data cols, got {len(data_row)}"
+        assert data_row[243] == "243.0", "last column value must be preserved"
+
+
+# ── Debug temperature conversion ───────────────────────────────────────────────
+
+
+class TestConvertDebugTemp:
+    """Spot-check known hex → debug temperature values.
+
+    Reference values derived from C#'s ConvertBinaryArrayToDebugTemp
+    (bits 4-14 scaled by 2**(i-8), sign at bit 0 — no family branching).
+    """
+
+    def test_zero_hex_gives_zero(self):
+        assert _convert_debug_temp("0000") == 0.0
+
+    def test_bit8_gives_one(self):
+        # bit index 8 set (value 0x0080) → contributes 2**(8-8) = 1.0
+        assert _convert_debug_temp("0080") == pytest.approx(1.0, abs=0.01)
+
+    def test_sign_bit_negates(self):
+        # sign bit (bit 0) + bit 8 → -1.0
+        assert _convert_debug_temp("8080") == pytest.approx(-1.0, abs=0.01)
+
+    def test_no_family_branching(self):
+        # Debug conversion takes no family code — same result regardless
+        assert _convert_debug_temp("0080") == _convert_debug_temp("0080")
+
+
+class TestConvertToDebugTemperatures:
+    def test_returns_same_shape(self):
+        hex_data = [["0080", "0000"], ["8080", "0000"]]
+        result = convert_to_debug_temperatures(hex_data)
+        assert len(result) == 2
+        assert len(result[0]) == 2
+
+    def test_values_are_strings(self):
+        result = convert_to_debug_temperatures([["0080"]])
+        assert isinstance(result[0][0], str)
+
+    def test_converts_known_value(self):
+        result = convert_to_debug_temperatures([["0080"]])
+        assert float(result[0][0]) == pytest.approx(1.0, abs=0.01)
+
+
+# ── Debug CSV export ────────────────────────────────────────────────────────────
+
+
+class TestSaveDebugCsv:
+    def test_creates_file_with_fixed_name(self, tmp_path):
+        result = save_debug_csv([["25.0"]], [["1.0"]], str(tmp_path))
+        assert result is not None
+        assert result.endswith("debug_info.csv")
+
+    def test_header_alternates_sensor_and_debug(self, tmp_path):
+        result = save_debug_csv([["25.0", "24.5"]], [["1.0", "2.0"]], str(tmp_path))
+        assert result is not None
+        header = open(result).readline().strip()
+        assert header == "Sensor1,Debug1,Sensor2,Debug2"
+
+    def test_data_row_alternates_values(self, tmp_path):
+        result = save_debug_csv([["25.0", "24.5"]], [["1.0", "2.0"]], str(tmp_path))
+        assert result is not None
+        lines = open(result).readlines()
+        assert lines[1].strip() == "25.0,1.0,24.5,2.0"
+
+    def test_truncates_to_shorter_row_count(self, tmp_path):
+        temp_data = [["25.0"], ["24.0"], ["23.0"]]
+        debug_data = [["1.0"], ["2.0"]]
+        result = save_debug_csv(temp_data, debug_data, str(tmp_path))
+        assert result is not None
+        lines = open(result).readlines()
+        assert len(lines) == 3  # 1 header + 2 data rows (shorter of the two)
+
+    def test_truncates_to_shorter_column_count(self, tmp_path):
+        temp_data = [["25.0", "24.0", "23.0"]]
+        debug_data = [["1.0", "2.0"]]
+        result = save_debug_csv(temp_data, debug_data, str(tmp_path))
+        assert result is not None
+        header = open(result).readline().strip()
+        assert header == "Sensor1,Debug1,Sensor2,Debug2"
+
+    def test_returns_none_on_empty_temp_data(self, tmp_path):
+        assert save_debug_csv([], [["1.0"]], str(tmp_path)) is None
+
+    def test_returns_none_on_empty_debug_data(self, tmp_path):
+        assert save_debug_csv([["25.0"]], [], str(tmp_path)) is None
+
+    def test_creates_output_dir_if_missing(self, tmp_path):
+        nested = str(tmp_path / "a" / "b")
+        result = save_debug_csv([["25.0"]], [["1.0"]], nested)
+        assert result is not None
+        from pathlib import Path
+
+        assert Path(result).exists()

tests/test_data_records.py

@@ -16,4 +16,4 @@ def test_reads_rows_after_data_marker(tmp_path):
     assert len(recs) == 2
     assert recs[0].time == 0.0
     assert recs[0].values == [149.0, 148.5]
-    assert recs[1].values == [149.2, 148.4]
+    assert recs[1].values == [149.2, 148.4]

tests/test_device_controller.py

@@ -1,10 +1,13 @@
-import pytest
 import logging
 from unittest.mock import MagicMock, patch
+
+import pytest
+
 from pygui.backend.controllers.device_controller import DeviceController
 from pygui.backend.data.local_settings import LocalSettings
 from pygui.serialcomm.serial_port import WaferInfo
 
+
 @pytest.fixture
 def mock_settings():
     s = LocalSettings()
@@ -16,8 +19,8 @@ def mock_settings():
 
 @pytest.fixture
 def controller(mock_settings):
-    import tempfile
     import shutil
+    import tempfile
     temp_dir = tempfile.mkdtemp()
     yield DeviceController(mock_settings, temp_dir)
     shutil.rmtree(temp_dir)
@@ -81,37 +84,112 @@ def test_clear_session(controller):
     controller._connection_status = "Connected"
     controller._selected_port = "COM1"
     controller._last_wafer_info = {"serialNumber": "P00001"}
-    
+
     controller.clearSession()
     assert controller.connectionStatus == "Disconnected"
     assert controller.selectedPort == ""
     assert controller.lastWaferInfo == ["", "", 0, "", 0, 0]
 
-def test_erase_memory(controller):
-    controller._service.erase_wafer = MagicMock(return_value=True)
+def test_erase_memory_spawns_thread(controller):
+    with patch("threading.Thread") as mock_thread:
+        controller.eraseMemory("COM1")
+        mock_thread.assert_called_once()
+        assert controller.operationInProgress
+
+def test_erase_memory_handler(controller):
     emitted_result = None
     def on_erase_result(result):
         nonlocal emitted_result
         emitted_result = result
 
     controller.eraseResult.connect(on_erase_result)
-    controller.eraseMemory("COM1")
+    controller._handle_erase_finished(True)
     assert emitted_result == {"success": True}
     assert controller.connectionStatus == "Connected"
+    assert not controller.operationInProgress
 
-def test_read_debug(controller):
-    controller._service.read_wafer_data = MagicMock(return_value=bytes([12] * 512))
+def test_read_debug_spawns_thread(controller):
+    with patch("threading.Thread") as mock_thread:
+        controller.readDebug("COM1")
+        mock_thread.assert_called_once()
+        assert controller.operationInProgress
+
+def test_read_debug_handler(controller):
     emitted_result = None
     def on_debug_result(result):
         nonlocal emitted_result
         emitted_result = result
 
     controller.debugResult.connect(on_debug_result)
-    controller.readDebug("COM1")
+    controller._handle_debug_finished({
+        "success": True,
+        "sensor_bytes": 512,
+        "debug_bytes": 512
+    })
     assert emitted_result is not None
     assert emitted_result.get("success") is True
     assert emitted_result.get("sensor_bytes") == 512
     assert emitted_result.get("debug_bytes") == 512
+    assert controller.connectionStatus == "Connected"
+    assert not controller.operationInProgress
+
+def _make_p_family_bytes(value: int = 0x0100) -> bytes:
+    """Synthetic single-block P-family binary: 244 valid words + 12 overhead."""
+    data = bytearray()
+    for i in range(256):
+        word = value if i < 244 else 0
+        data += word.to_bytes(2, byteorder="little")
+    return bytes(data)
+
+
+def test_debug_worker_decodes_and_saves_csv(controller, tmp_path):
+    controller._last_wafer_info = {"familyCode": "P"}
+    controller._save_data_dir = str(tmp_path)
+    controller._service.read_wafer_data = MagicMock(
+        side_effect=[_make_p_family_bytes(), _make_p_family_bytes()]
+    )
+
+    captured = {}
+    controller._debugFinished.connect(captured.update)
+
+    controller._debug_worker("COM1")
+
+    assert captured.get("success") is True
+    assert captured.get("sensor_bytes") == 512
+    assert captured.get("debug_bytes") == 512
+    assert "csv_path" in captured
+    from pathlib import Path
+    assert Path(captured["csv_path"]).exists()
+    assert Path(captured["csv_path"]).name == "debug_info.csv"
+
+
+def test_debug_worker_reports_error_when_csv_save_fails(controller, tmp_path):
+    controller._last_wafer_info = {"familyCode": "P"}
+    # Point save dir somewhere save_debug_csv cannot write to, so it returns None.
+    controller._save_data_dir = str(tmp_path / "debug_info.csv")  # a file, not a dir
+    (tmp_path / "debug_info.csv").write_text("occupied")
+    controller._service.read_wafer_data = MagicMock(
+        side_effect=[_make_p_family_bytes(), _make_p_family_bytes()]
+    )
+
+    captured = {}
+    controller._debugFinished.connect(captured.update)
+
+    controller._debug_worker("COM1")
+
+    assert captured.get("success") is not True
+    assert "error" in captured
+
+
+def test_debug_handler_logs_csv_path(controller):
+    controller._handle_debug_finished({
+        "success": True,
+        "sensor_bytes": 512,
+        "debug_bytes": 512,
+        "csv_path": "/tmp/debug_info.csv",
+    })
+    assert "/tmp/debug_info.csv" in controller.activityLog
+
 
 def test_parse_and_save_data_and_get_chart_data(controller):
     res = controller.getChartData()
@@ -125,7 +203,7 @@ def test_parse_and_save_data_and_get_chart_data(controller):
 
     controller.parsedDataReady.connect(on_parsed)
     controller.parseAndSaveData("P", "COM1")
-    
+
     assert emitted_result is not None
     assert emitted_result.get("success") is True
     assert controller.dataRowCount == 1
@@ -142,16 +220,16 @@ def test_logging_handler(controller):
     assert any("Hello QML Activity Log" in line for line in controller._activity_log)
 
 def test_fresh_session_on_startup(mock_settings):
-    import tempfile
     import shutil
-    
+    import tempfile
+
     # Configure mock settings with some data to simulate previous session
     mock_settings.activity_log = ["[12:00:00] Old message"]
     mock_settings.selected_port = "COM9"
     mock_settings.last_wafer_info = {"familyCode": "P", "serialNumber": "P00002"}
     mock_settings.data_row_count = 50
     mock_settings.data_col_count = 244
-    
+
     temp_dir = tempfile.mkdtemp()
     try:
         new_controller = DeviceController(mock_settings, temp_dir)
@@ -170,20 +248,55 @@ def test_detect_wafer_clears_old_session(controller):
     controller._data_row_count = 10
     controller._data_col_count = 244
     controller._activity_log.append("[12:00:00] Previous message")
-    
+
     # We mock detect_all_ports to not run long or fail
     controller._service.detect_all_ports = MagicMock(return_value=(None, None))
-    
-    with patch("threading.Thread") as mock_thread:
+
+    with patch("threading.Thread"):
         controller.detectWafer()
-        
+
         # Verify it cleared all session variables and logs immediately at start of detect
         assert controller.selectedPort == ""
         assert controller.lastWaferInfo == ["", "", 0, "", 0, 0]
         assert controller.dataRowCount == 0
         assert controller.dataColCount == 0
-        
+
         # Log should only contain "Scanning all ports for wafer ..."
         assert len(controller._activity_log) == 1
         assert "Scanning all ports" in controller._activity_log[0]
 
+def test_device_service_port_caching(controller):
+    service = controller._service
+    # Mock comports list
+    with patch("serial.tools.list_ports.comports", return_value=[]), \
+         patch("subprocess.run") as mock_run:
+        # Mock subprocess to return empty
+        mock_run.return_value.returncode = 0
+        mock_run.return_value.stdout = ""
+
+        # Clear cache first
+        service.clear_port_scan_cache()
+
+        # First scan should invoke list_ports and subprocess
+        ports1 = service.enumerate_ports()
+        assert mock_run.call_count == 1
+
+        # Second scan within 2 seconds should return cached list without invoking subprocess
+        ports2 = service.enumerate_ports()
+        assert mock_run.call_count == 1
+        assert ports1 == ports2
+
+        # Clear cache and scan again should invoke subprocess
+        service.clear_port_scan_cache()
+        service.enumerate_ports()
+        assert mock_run.call_count == 2
+
+
+
+def test_export_dir_created_under_save_data_dir(controller):
+    from pathlib import Path
+
+    result = controller.exportDir()
+
+    assert result == str(Path(controller.saveDataDir) / "Export")
+    assert Path(result).is_dir()

tests/test_device_controller_license.py

@@ -0,0 +1,8 @@
+# TODO P4.2: unit tests for the DeviceController license guard (plan §4.2,
+#   docs/pending/license-gating-plan.md). Two cases:
+#   1. license_lookup=lambda s: "" + fake _last_wafer_info → readMemoryAsync()
+#      emits readResult {"error": ...} and spawns no thread.
+#   2. lookup returning "02" → proceeds to _read_worker (mock DeviceService).
+#   THINKING: guard is a trust boundary (plan §2.1); these fail if someone
+#   reorders the busy/license checks or renames the "serialNumber" key.
+#   Depends on P1.2 + P2.1 being implemented.

tests/test_family_spec.py

@@ -0,0 +1,23 @@
+"""Tests for the shared wafer family sensor-count lookup."""
+from pygui.backend.wafer.family_spec import sensor_count_for
+
+
+def test_x_family_returns_80():
+    assert sensor_count_for("X") == 80
+
+
+def test_p_family_returns_244():
+    assert sensor_count_for("P") == 244
+
+
+def test_other_known_families_return_244():
+    for code in ("A", "B", "C", "D", "E", "F"):
+        assert sensor_count_for(code) == 244
+
+
+def test_unknown_family_returns_244():
+    assert sensor_count_for("Z") == 244
+
+
+def test_empty_string_returns_244():
+    assert sensor_count_for("") == 244

tests/test_file_browser.py

@@ -0,0 +1,43 @@
+from pathlib import Path
+
+from pygui.backend.data.file_browser import FileBrowser
+
+
+def _write_csv(path, wafer_id="P00001"):
+    path.write_text(
+        f"Wafer ID={wafer_id}\n"
+        "Acquisition Date=03/26/2025\n"
+        "Label,1,2,3\n"
+        "X (mm),0,10,-10\n"
+        "Y (mm),10,-10,-10\n"
+        "data\n"
+        "0.0,149.0,148.5,150.6\n"
+    )
+
+
+def test_recorded_live_file_flagged_as_recording(qapp, tmp_path):
+    """Files named live_<serial>_<timestamp>.csv (SessionController.startRecording)
+    must be distinguishable in the browser from read-memory dumps."""
+    _write_csv(tmp_path / "live_P00001_20260706_143022.csv")
+    _write_csv(tmp_path / "P00002-20260706_143500.csv")
+
+    browser = FileBrowser()
+    browser._set_current_directory(tmp_path)
+    browser.refreshFiles()
+
+    files_by_name = {Path(row["fileName"]).name: row for row in browser.files}
+    assert files_by_name["live_P00001_20260706_143022.csv"]["isRecording"] is True
+    assert files_by_name["P00002-20260706_143500.csv"]["isRecording"] is False
+
+
+def test_set_current_directory_updates_dir_and_refreshes(qapp, tmp_path):
+    """setCurrentDirectory (no native dialog) is how the Status tab's save-dir
+    picker keeps the Source panel pointed at the same folder."""
+    _write_csv(tmp_path / "P00003-20260706_143500.csv")
+
+    browser = FileBrowser()
+    browser.setCurrentDirectory(str(tmp_path))
+
+    assert browser.currentDirectory == str(tmp_path)
+    assert len(browser.files) == 1
+    assert Path(browser.files[0]["fileName"]).name == "P00003-20260706_143500.csv"