fix(paths): centralize file:// URL handling to fix broken save-dir paths

src/pygui/ISC/FirstLaunchWizard.qml

@@ -43,7 +43,7 @@ Popup {
         id: saveDirDialog
         title: "Choose a folder to save data"
         onAccepted: {
-            var dir = decodeURIComponent(String(selectedFolder).replace(/^file:\/\//, ""))
+            var dir = String(selectedFolder)
             deviceController.setSaveDataDir(dir)
             file_browser.setCurrentDirectory(dir)
             root.finished()

src/pygui/ISC/HomePage.qml

@@ -171,10 +171,6 @@ Rectangle {
         }
     }
 
-    function cleanFolderUrl(url) {
-        return decodeURIComponent(String(url).replace(/^file:\/\//, ""))
-    }
-
     function _doDetect() {
         root.memoryRead = false
         root.waferDetected = false
@@ -187,7 +183,7 @@ Rectangle {
         id: saveDirDialog
         title: "Choose a folder to save Data"
         onAccepted: {
-            var dir = root.cleanFolderUrl(selectedFolder)
+            var dir = String(selectedFolder)
             deviceController.setSaveDataDir(dir)
             file_browser.setCurrentDirectory(dir)
             root._doDetect()

src/pygui/ISC/Tabs/StatusTab.qml

@@ -113,9 +113,6 @@ ColumnLayout {
     readonly property bool isBusy: deviceController.connectionStatus.endsWith("...")
     readonly property string portName: deviceController.selectedPort || "—"
 
-    function cleanFolderUrl(url) {
-        return decodeURIComponent(String(url).replace(/^file:\/\//, ""));
-    }
     function currentFamilyCode() {
         var info = deviceController.lastWaferInfo;
         return info && info.length > 0 ? (info[0] || "") : "";
@@ -128,7 +125,7 @@ ColumnLayout {
         id: saveDirDialog
         title: "Choose a folder to save."
         onAccepted: {
-            var dir = root.cleanFolderUrl(selectedFolder);
+            var dir = String(selectedFolder);
             deviceController.setSaveDataDir(dir);
             file_browser.setCurrentDirectory(dir);
             root.parseAndSavePendingRead();
@@ -141,7 +138,7 @@ ColumnLayout {
         id: dirOnlyDialog
         title: "Choose a folder to save Data"
         onAccepted: {
-            var dir = root.cleanFolderUrl(selectedFolder);
+            var dir = String(selectedFolder);
             deviceController.setSaveDataDir(dir);
             file_browser.setCurrentDirectory(dir);
         }

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

@@ -260,14 +260,14 @@ ColumnLayout {
         id: importFileDialog
         title: "Select Data File To Import"
         nameFilters: ["CSV files (*.csv)"]
-        onAccepted: file_browser.importZWaferCsv(String(selectedFile).replace(/^file:\/\//, ""))
+        onAccepted: file_browser.importZWaferCsv(String(selectedFile))
     }
 
     FolderDialog {
         id: batchExportDirDialog
         title: "Export Wafer Maps To…"
         onAccepted: {
-            var dir = String(selectedFolder).replace(/^file:\/\//, "");
+            var dir = String(selectedFolder);
             var paths = file_browser.files.map(function(row) { return row.fileName; });
             batchExportController.start(paths, dir);
         }

src/pygui/backend/controllers/batch_export_controller.py

@@ -5,7 +5,7 @@ import threading
 
 from PySide6.QtCore import Property, QObject, Qt, Signal, Slot
 
-from pygui.backend.utils import slot_error_boundary
+from pygui.backend.utils import slot_error_boundary, to_local_path
 from pygui.backend.wafer.batch_export import BatchExportResult, export_batch
 
 log = logging.getLogger(__name__)
@@ -33,7 +33,9 @@ class BatchExportController(QObject):
         self._busy = True
         self.busyChanged.emit()
         threading.Thread(
-            target=self._worker, args=(list(file_paths), output_dir), daemon=True
+            target=self._worker,
+            args=(list(file_paths), str(to_local_path(output_dir))),
+            daemon=True,
         ).start()
 
     def _worker(self, file_paths: list[str], output_dir: str) -> None:

src/pygui/backend/controllers/device_controller.py

@@ -15,7 +15,7 @@ from PySide6.QtCore import Property, QObject, Qt, Signal, Slot
 
 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.utils import slot_error_boundary, to_local_path
 from pygui.backend.visualization.graph_view import GraphView
 from pygui.serialcomm.data_parser import (
     convert_to_debug_temperatures,
@@ -82,7 +82,8 @@ class DeviceController(QObject):
         self._operation_in_progress = False
         self._activity_log: list[str] = []
         self._raw_bytes: Optional[bytes] = None
-        self._save_data_dir: str = getattr(settings, 'save_data_dir', "") or str(Path(self._data_dir) / "csv")
+        saved_dir = getattr(settings, 'save_data_dir', "")
+        self._save_data_dir: str = str(to_local_path(saved_dir)) if saved_dir else str(Path(self._data_dir) / "csv")
         self._last_wafer_info: dict[str, Any] = {}
         self._wafer_detected: bool = False
         self._last_csv_path: str = ""
@@ -141,8 +142,8 @@ class DeviceController(QObject):
     @slot_error_boundary
     def setSaveDataDir(self, path: str) -> None:
         """Set the directory for saving parsed CSV data files."""
-        self._save_data_dir = path
-        self._append_log(f"Save data dir set to: {path}")
+        self._save_data_dir = str(to_local_path(path))
+        self._append_log(f"Save data dir set to: {self._save_data_dir}")
         self._save_status()
 
     @Slot(result=str)

src/pygui/backend/data/file_browser.py

@@ -10,6 +10,7 @@ from PySide6.QtWidgets import QFileDialog, QMessageBox
 
 from pygui.backend.data.constants import default_data_dir
 from pygui.backend.data.csv_file_metadata import CSVFileMetadata
+from pygui.backend.utils import to_local_path
 from pygui.backend.wafer.zwafer_parser import ZWaferParser
 
 
@@ -45,7 +46,7 @@ class FileBrowser(QObject):
         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._set_current_directory(to_local_path(path))
         self._refresh_files(show_empty_message=False)
 
     @Slot()
@@ -124,7 +125,8 @@ class FileBrowser(QObject):
         date still gets a deterministic (if degenerate) filename, so the
         duplicate-import guard below still fires on a second attempt.
         """
-        source_path = Path(file_path)
+        source_path = to_local_path(file_path)
+        file_path = str(source_path)
         parser_data, _ = self._parser.parse(file_path)
         if parser_data is None:
             self.importFinished.emit("", f"Failed to parse CSV:\n{source_path.name}")

src/pygui/backend/license/license_model.py

@@ -5,7 +5,7 @@ import shutil
 import time
 from pathlib import Path
 
-from PySide6.QtCore import Property, QObject, QUrl, Signal, Slot
+from PySide6.QtCore import Property, QObject, Signal, Slot
 
 from pygui.backend.license.license_manager import (
     LICENSE_FILENAME_RE,
@@ -13,25 +13,13 @@ from pygui.backend.license.license_manager import (
     parse_license_blob,
     read_license_files,
 )
+from pygui.backend.utils import to_local_path as _to_local_path
 
 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).
-
-    Uses QUrl.toLocalFile() rather than urlparse — a manual
-    urlparse().path strip leaves a leading slash before a Windows drive
-    letter (e.g. "/C:/Users/...", not a valid absolute path), which
-    QUrl's platform-aware conversion handles correctly.
-    """
-    if path_or_url.startswith("file:"):
-        return Path(QUrl(path_or_url).toLocalFile())
-    return Path(path_or_url)
-
-
 # ===== License Model =====
 class LicenseModel(QObject):
     """Context property backing the About dialog license grid.

src/pygui/backend/utils.py

@@ -1,5 +1,26 @@
 import logging
+import re
 from functools import wraps
+from pathlib import Path
+
+from PySide6.QtCore import QUrl
+
+_MANGLED_DRIVE_RE = re.compile(r"^/([A-Za-z]:)")
+
+
+def to_local_path(path_or_url: str) -> Path:
+    """Accept plain paths, file:// URLs, and already-mangled "/C:/..." strings
+    (persisted by old buggy code before it stripped file:// by hand).
+
+    Uses QUrl.toLocalFile() rather than a manual string strip — stripping
+    "file://" by hand leaves a leading slash before a Windows drive letter
+    (e.g. "/C:/Users/...", not a valid absolute path), which QUrl's
+    platform-aware conversion handles correctly.
+    """
+    if path_or_url.startswith("file:"):
+        return Path(QUrl(path_or_url).toLocalFile())
+    # ponytail: repair values saved by the old regex-stripping QML code
+    return Path(_MANGLED_DRIVE_RE.sub(r"\1", path_or_url))
 
 
 def slot_error_boundary(func):