taskbot/README.md

# Task WhatsApp Chatbot

A WhatsApp chatbot for task management, designed to work with Evolution API in a secure internal network environment.

## 📌 Overview
This service provides a WhatsApp interface for task management within WhatsApp groups. It:
- Listens for `/tarea` commands in WhatsApp groups via Evolution API webhooks.
- Stores tasks, users, and groups in a SQLite database.
- Synchronizes group information periodically from the Evolution API.
- Manages user permissions and group membership (partially implemented).
- Integrates with Evolution API for WhatsApp connectivity.

## 🔐 Security Model
- **Internal Networking**: The webhook should ideally only accept connections from Evolution API via internal Docker networking (configuration dependent).
- **Environment Variables**: Sensitive configuration (API keys, URLs) is managed through environment variables.
- **Group Restrictions**: Designed to operate within pre-approved WhatsApp groups (validation logic pending implementation).
- **Input Validation**: Basic validation exists for webhook structure; needs enhancement for command arguments and user/group IDs.

## 🧱 Architecture
```mermaid
graph TD
    A[Webhook Received] --> B{Valid Payload?}
    B -->|No| C[Ignore]
    B -->|Yes| D{Normalize IDs & Check Group Active?}
    D -->|No| C[Ignore/Log]
    D -->|Yes| E[Ensure User Exists in DB]
    E --> G{/tarea Command?}
    G -->|No| C
    G -->|Yes| J[Process Command Logic]
    J -- Success/Error --> K[Queue Response(s)]
    K --> L[Process Queue & Send Response via API]

    subgraph Database Interaction
        E --> DB[(SQLite DB)]
        J --> DB
    end
    subgraph Evolution API
        L --> EA((Evolution API))
        EA -- Webhook --> A
    end
```
*(Diagram updated for planned flow)*

## ✅ Current Status (as of commit dd32a3d)
### Implemented
- Webhook server setup (`src/server.ts`) receiving Evolution API events.
- Database schema definition and initialization (`src/db.ts`).
- Group synchronization service (`src/services/group-sync.ts`) to fetch/store/cache groups.
- Webhook registration and verification with Evolution API (`src/services/webhook-manager.ts`).
- Basic `/tarea` command detection and argument parsing structure (`src/server.ts`).
- Task data models (`src/tasks/model.ts`).
- Basic task creation service stub (`src/tasks/service.ts` - needs `created_by` and assignment logic).
- Response queue structure (`src/services/response-queue.ts` - `process` method is empty).
- Unit testing setup with in-memory database (`tests/`).
- Environment variable validation (`src/server.ts`, `src/services/webhook-manager.ts`).
- Health check endpoint (`/health`).

### Incomplete / Missing Core Functionality
- **User/Group Validation:** No normalization of WhatsApp IDs or checking if messages originate from active, known groups. Users are not automatically added to the DB.
- **Core Command Logic:** Actual processing of `/tarea nueva` (parsing args, calling `TaskService`) is missing in `CommandService`. Other commands (`mostrar`, `completar`) not implemented.
- **Task Service Implementation:** `TaskService` needs updating to handle `created_by`, assignments, and potentially methods for listing/completing tasks.
- **Response Sending:** `ResponseQueue` does not yet send messages back via the Evolution API.
- **Database Migrations:** No system in place to manage schema changes.
- **Robust Error Handling:** Comprehensive error handling, logging, and transaction management need improvement, especially around API calls and DB operations.

## 🛠️ Setup
### Environment Variables
*(Ensure these are set correctly)*
```env
# Evolution API Connection
EVOLUTION_API_URL=http://evolution-api:3000 # Or your API URL
EVOLUTION_API_KEY=your-api-key
EVOLUTION_API_INSTANCE=main # Your instance name

# WhatsApp Specific
WHATSAPP_COMMUNITY_ID=your-community-id # ID of the main community to sync groups from
CHATBOT_PHONE_NUMBER=1234567890 # Bot's normalized phone number (e.g., for assigning tasks)

# Webhook Configuration
WEBHOOK_URL=http://your-service-internal-url:3007 # URL Evolution API calls *back* to this service
PORT=3007 # Port this service listens on

# Runtime Environment
NODE_ENV=production # Or development

# Optional
# GROUP_SYNC_INTERVAL_MS=3600000 # Sync interval in ms (default: 24h)
```

### Development Setup
```bash
# Install dependencies
bun install

# Copy .env.example to .env and fill in values
cp .env.example .env

# Start development server (watches for changes)
bun run dev

# Run tests
bun test
```

## 📅 Roadmap & Priorities (Plan)

### Phase 1: User & Group Foundation (Highest Priority)
- [ ] **Create WhatsApp ID Normalization Utility:** (`src/utils/whatsapp.ts`) Handle different ID formats.
- [ ] **Implement `ensureUserExists`:** (`src/db.ts`) Add users to DB on first interaction.
- [ ] **Implement `isGroupActive` Check:** (`src/services/group-sync.ts`, `src/server.ts`) Validate incoming messages are from known, active groups.
- [ ] **Integrate Validation in Server:** (`src/server.ts`) Use normalization and validation before processing commands.

### Phase 2: Implement `/tarea nueva` Command (High Priority)
- [ ] **Update `TaskService.createTask`:** (`src/tasks/service.ts`) Handle `created_by` and assignments (including adding assigned users via `ensureUserExists`).
- [ ] **Implement `/tarea nueva` Logic:** (`src/services/command.ts`) Parse description, due date, mentions; call `TaskService`; generate response messages.

### Phase 3: Implement Response Sending (High Priority)
- [ ] **Implement `ResponseQueue.process`:** (`src/services/response-queue.ts`) Send queued messages via Evolution API's send endpoint.
- [ ] **Trigger Queue Processing:** (`src/server.ts`) Call `ResponseQueue.process()` after command handling.

### Phase 4: Further Commands & Refinements (Medium Priority)
- [ ] Implement `/tarea mostrar [group|mine]` command.
- [ ] Implement `/tarea completar <task_id>` command.
- [ ] Add Database Migrations system.
- [ ] Improve Error Handling & Logging (API calls, DB transactions).
- [ ] Refine Group Sync (Delta updates).

### Phase 5: Advanced Features (Low Priority)
- [ ] Add task reminders system.
- [ ] Implement user permissions system.
- [ ] Add rate limiting.
- [ ] Create task history tracking.

## 🔑 Key Considerations & Caveats
*   **WhatsApp ID Normalization:** Crucial for consistently identifying users and groups. Needs careful implementation to handle edge cases.
*   **Response Latency:** Sending responses requires an API call back to Evolution. Ensure the `ResponseQueue` processing is efficient.
*   **Group Sync:** The current full sync might be slow or rate-limited with many groups. Delta updates are recommended long-term.
*   **Error Handling:** Failures in command processing or response sending should be logged clearly and potentially reported back to the user. Database operations should use transactions for atomicity (especially task+assignment creation).
*   **State Management:** The current design is stateless. Complex interactions might require state persistence later.
*   **Security:** Ensure group/user validation logic is robust.

## 🧪 Testing
### Running Tests
```bash
bun test
```

### Test Coverage
- Database initialization and basic operations.
- Webhook validation (basic).
- Command parsing (basic structure).
- Environment checks.
- Basic error handling.
- **Needed:** Tests for ID normalization, `ensureUserExists`, `isGroupActive`, `CommandService` logic, `ResponseQueue` processing (mocking API), `TaskService` operations.

## 🧑‍💻 Contributing
1. Fork the repository
2. Create a feature branch (`git checkout -b feature/implement-user-validation`)
3. Add/update tests for new functionality
4. Ensure tests pass (`bun test`)
5. Submit a pull request

## 📚 Documentation
For detailed API documentation and architecture decisions, see the [docs/](docs/) directory (if created).