# Coordination Plan: Barcode Picking & QR Print Integration

This document outlines the design and integration process of the **CSG Part Verifier** (mobile picking interface) and the **QR Label printing** logic. It is written to provide full context for other AI agents working on the desktop application.

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## 1. Overview of the Integration

We are adding two features to the ecosystem:
1. **Mobile Picking Client (Android & PC):** Allows operators on the warehouse floor to scan invoice QR codes, pull up pick lists, and verify items by scanning box QR codes.
2. **Label QR Code Printing:** Updates GDI label generation so all printed labels contain layout-compliant QR codes (Invoice Number for shipping address labels, SKU string for part labels).

To keep this a **drop-in solution** without interfering with the active desktop app structure:
- **No Direct Printing:** The desktop app will no longer run direct GDI print calls locally via `win32print`. Instead, it will post all print requests to the existing `qb_efficiency` bridge server.
- **Background Web Server:** We will spawn a lightweight background Flask thread inside the desktop app. This thread will run on a separate port (`5001`) to serve the mobile picking client and lookup invoices.
- **Zero Database Overhead:** The picking server will read live invoice data from the existing `qb_efficiency` sync result folder.

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## 2. Shared File Changes & Additions

### Active Build: `Part Lookup Program (1)`

1. **[NEW] `app/picker_server.py`:**
   - Spawns a Flask web server on a background thread.
   - Listens on `port 5001`.
   - Serves static picker UI files (`picker.html` and `picker.js`) located in `app/assets/`.
   - **`GET /api/invoice/<ref_number>`:** Resolves invoice line items by reading and parsing the cached QuickBooks results from `C:/Users/mario/OneDrive/Documents/Claude/Projects/qb_efficiency/qb-bridge/state/results/invoice_*.json`.
   - **`POST /api/print-label`:** Forwards print requests to the local `qb_efficiency` print bridge (`http://localhost:5000/api/label-jobs/enqueue`).

2. **[NEW] `run_picker.py`:**
   - Standalone startup script that runs the Flask server on the host machine. Run it to launch the mobile picking assistant independently (keeps the desktop app completely separate).

3. **[MODIFY] `app/labels.py`:**
   - Refactor `print_label` and `print_address_label` to make HTTP POST requests to the `qb_efficiency` enqueue endpoint:
     ```python
     # Example POST to http://localhost:5000/api/label-jobs/enqueue
     payload = {
         "label_data": {
             "order_id": sku_or_invoice_id,
             "source": "parts_lookup",
             "skus": [{"sku": sku, "description": desc, "line_qty": 1}]
         }
     }
     ```

4. **[NEW] `app/assets/picker.html` & `app/assets/picker.js`:**
   - HTML5 video element container and canvas processing script.
   - Integrates the `html5-qrcode` library for high-speed camera scanning.
   - Handles item checklists, verification matching, and audio success/error feedback.

5. **[MODIFY] `PartsLookup.spec`:**
   - Update PyInstaller datas config to copy `app/assets/picker.html` and `app/assets/picker.js` into the compiled bundle resources folder.

---

## 3. QB Efficiency: `qb_efficiency`

1. **[MODIFY] `qb-bridge/label_agent/csg_label_agent.py`:**
   - Install and import the `qrcode` library.
   - Update both GDI renderers (`_render_sku_label` and `_render_shipping_label`) to generate a QR image (containing either the SKU or Invoice Number).
   - Use Pillow's `ImageWin.Dib` to draw the QR code on the print context alongside the existing CSG logo and Made-in-USA logo.

---

## 4. Verification Details

- **Dependencies:** Run `pip install qrcode pillow flask requests` in the python environment.
- **Port Mapping:**
  - `qb_efficiency` Flask Bridge runs on `5000`.
  - `csg_label_agent.py` print agent polls `5000` and prints labels.
  - Desktop app background picker thread runs on `5001`.
  - Android device accesses picking page at `http://<host-pc-ip>:5001/picker`.