# HPGL Plotter Web UI

Flask web interface for uploading HPGL files, previewing and transforming them (flip, rotate, scale, center), and sending to the plotter. Intended to run on a Raspberry Pi connected to the plotter via USB.

## Setup (Raspberry Pi)

1. From the **project root** (mimaki/), install dependencies:

   If you get **externally-managed-environment** (Python 3.11+ / PEP 668) and don’t want a venv, use:
   ```bash
   pip install --break-system-packages -r webui/requirements.txt
   ```
   Otherwise:
   ```bash
   pip install -r webui/requirements.txt
   ```
   Optional – use a venv to avoid touching system Python:
   ```bash
   python3 -m venv venv
   source venv/bin/activate
   pip install -r webui/requirements.txt
   ```

2. **Config:** Copy `config.example.ini` to `config.ini` and adjust (port, baudrate, web UI host/port, etc.). `config.ini` is gitignored.
   ```bash
   cp config.example.ini config.ini
   ```
   Edit `config.ini` to set the plotter port (e.g. `/dev/ttyUSB0`) and optionally web UI port/host.

## Run

From the **project root** (mimaki/):

```bash
python webui/app.py
```

Then open http://&lt;raspi-ip&gt;:5000 in a browser (e.g. http://192.168.1.10:5000).

- **Host:** `0.0.0.0` so other devices on the network can connect.
- **Port:** 5000 (override with `PORT=8080 python webui/app.py` if needed).

For production, run behind gunicorn and optionally a reverse proxy:

```bash
pip install --break-system-packages gunicorn   # or omit if not using system Python
gunicorn -w 1 -b 0.0.0.0:5000 "webui.app:app"
```

## Usage

1. **Upload** – Choose an `.hpgl` or `.plt` file. It is validated and stored in `webui/uploads/`.
2. **Preview** – The drawing is converted to SVG and shown in the browser.
3. **Transform** – Flip, Rotate 90° / 180°, Scale + / −, Center. Each action updates the stored program and the preview.
4. **Print** – Sends the current (transformed) program to the plotter: scale to fit, center, then write HPGL to serial.

## API

- `POST /api/upload` – Upload HPGL file (form field `file`).
- `GET /api/svg` – Get current program as SVG (query: `width`, `height`).
- `POST /api/transform` – Body: `{"action": "flip"|"rotate"|"scale"|"centralize", "angle": 90, "factor": 1.25}`.
- `POST /api/print` – Send current program to plotter.
- `GET /api/status` – `has_file`, `filename`, `plotter_ready`.

Session is used to keep the current file path; no database.
