# Wafer Position Monitor (demo)

PySide6 desktop demo: load NanoBerry edge CSVs from `MASTER_SD/`, fit a wafer circle, show **X / Y / theta** offset and **sigma** vs a calibration baseline. No live camera integrated yet.

**Stack:** Python 3.11+, PySide6, NumPy.

## Quick start

```bash
python3 -m venv .venv && source .venv/bin/activate
pip install -e .
wafer-user          # or: python src/wafer_edge/App.py
```

Click **Read Wafer** to load the demo CSVs. Tests: `python -m pytest tests/` (UI smoke needs a display).

## Data

**Real data** — `[MASTER_SD/](MASTER_SD/)`: CSV files from actual NanoBerry camera captures. Names: `{S|R}{1|2}{seq}P0.CSV` — local/remote board, SPI camera, 4-digit sequence (e.g. `S10540P0.CSV`).

**Fabricated data** — `[DATA/0610/](DATA/)`: Generated test data used by `CsvSource.DEMO_CAMERA_PATHS` (the default demo source). Change that dict or use `parse_csv_filename()` for other captures.

## Calibration

First run creates `baseline.json` (gitignored). Key fields: `center_mm`, `radius_mm` (75), `center_px`, `radius_px` (pixel scale).

## Layout

| Path                    | Role                              |
| ----------------------- | --------------------------------- |
| `src/wafer_edge/App.py` | Main window                       |
| `VisionEngine.py`       | Circle fit + offsets (no Qt)      |
| `CsvSource.py`          | CSV loader                        |
| `ui/widgets.py`         | Plot + metric cards               |
| `ui/Theme.qml`          | Styles (loaded via `ui/theme.py`) |

**Pipeline:** `DEMO_CAMERA_PATHS` → `load_camera_records_from_csv()` → `snapshot_from_records()` → UI.

## Alignment states

The monitor derives one of three states from the fitted circle on every read:

| State        | Condition                            | Dot      |
| ------------ | ------------------------------------ | -------- |
| **Ready**    | offset ≤ 0.10 mm **and** σ ≤ 0.05 mm | 🟢 green |
| **Aligning** | offset ≤ 0.50 mm **and** σ ≤ 0.20 mm | 🟡 amber |
| **Fault**    | offset > 0.50 mm **or** σ > 0.20 mm  | 🔴 red   |

### Ready — wafer within tolerance

![Ready state](screenshots/state_ready.png)

### Aligning — wafer correcting, noisy cameras

![Aligning state](screenshots/state_aligning.png)

### Fault — wafer out of range

![Fault state](screenshots/state_fault.png)