# Bridge WhatsApp

WhatsApp integration service for the CDR Link communication bridge system.

## Overview

Bridge WhatsApp provides a REST API for sending and receiving WhatsApp messages using the Baileys library (WhatsApp Web API). It handles bot session management, message routing, and media processing for WhatsApp communication channels.

## Features

- **Bot Management**: Register and manage multiple WhatsApp bot sessions
- **Message Handling**: Send and receive text messages with formatting
- **Media Support**: Handle images, documents, audio, and video files
- **QR Code Authentication**: Web-based WhatsApp authentication
- **REST API**: Simple HTTP endpoints for integration

## Development

### Prerequisites

- Node.js >= 20
- npm >= 10
- PostgreSQL database (for bot configuration)

### Setup

```bash
# Install dependencies
npm install

# Build TypeScript
npm run build

# Run development server
npm run dev

# Start production server
npm run start
```

### Environment Variables

- `PORT` - Server port (default: 5000)
- `DATABASE_URL` - PostgreSQL connection string (optional)
- Additional WhatsApp-specific configuration as needed

### Available Scripts

- `npm run build` - Compile TypeScript
- `npm run dev` - Development mode with auto-reload
- `npm run start` - Start production server

## API Endpoints

### Bot Management

- `POST /api/bots/:token` - Register/initialize a bot
- `GET /api/bots/:token` - Get bot status and QR code

### Messaging

- `POST /api/bots/:token/send` - Send a message
- `POST /api/bots/:token/receive` - Webhook for incoming messages

### Request/Response Format

#### Send Message

```json
{
  "to": "1234567890@s.whatsapp.net",
  "message": "Hello World",
  "media": {
    "url": "https://example.com/image.jpg",
    "type": "image"
  }
}
```

#### Receive Message Webhook

```json
{
  "from": "1234567890@s.whatsapp.net",
  "message": "Hello",
  "timestamp": "2024-01-01T00:00:00Z",
  "media": {
    "url": "https://...",
    "type": "image",
    "mimetype": "image/jpeg"
  }
}
```

## Architecture

### Server Framework

Built with Hapi.js for:

- Route validation
- Plugin architecture
- Error handling
- Request lifecycle

### WhatsApp Integration

Uses @whiskeysockets/baileys:

- WhatsApp Web protocol
- Multi-device support
- Message encryption
- Media handling

### Session Management

- File-based session storage
- Automatic reconnection
- QR code regeneration
- Session cleanup

## Media Handling

Supported media types:

- **Images**: JPEG, PNG, GIF
- **Documents**: PDF, DOC, DOCX
- **Audio**: MP3, OGG, WAV
- **Video**: MP4, AVI

Media is processed and uploaded before sending.

## Error Handling

- Connection errors trigger reconnection
- Invalid sessions regenerate QR codes
- API errors return appropriate HTTP status codes
- Comprehensive logging for debugging

## Security

- Token-based bot authentication
- Message validation
- Rate limiting (configurable)
- Secure session storage

## Integration

Designed to work with:

- **bridge-worker**: Processes WhatsApp message jobs
- **bridge-frontend**: Manages bot configuration
- External webhooks for message routing

## Docker Support

```bash
# Build image
docker build -t link-stack/bridge-whatsapp .

# Run container
docker run -p 5000:5000 link-stack/bridge-whatsapp
```

## Testing

While test configuration exists (jest.config.json), tests should be implemented for:

- API endpoint validation
- Message processing logic
- Session management
- Error scenarios