Complete rewrite from task management to full-featured chat system:
Core Features:
- Real-time WebSocket messaging with connection management
- Direct messages and group chats with admin controls
- Message types: text, images, videos, audio, documents
- Message status tracking: sent, delivered, read receipts
- Typing indicators and user presence (online/offline)
- Message replies, editing, and deletion
Security & Encryption:
- End-to-end encryption with RSA + AES hybrid approach
- JWT authentication for API and WebSocket connections
- Secure file storage with access control
- Automatic RSA key pair generation per user
Media & File Sharing:
- Multi-format file upload (images, videos, audio, documents)
- Automatic thumbnail generation for images/videos
- File size validation and MIME type checking
- Secure download endpoints with permission checks
Notifications & Alerts:
- Real-time WebSocket notifications
- Push notifications via Firebase integration
- @username mention alerts with notification history
- Unread message and mention counting
- Custom notification types (message, mention, group invite)
Advanced Features:
- Group chat management with roles (member, admin, owner)
- User search and chat member management
- Message pagination and chat history
- Last seen timestamps and activity tracking
- Comprehensive API documentation with WebSocket events
Architecture:
- Clean layered architecture with services, models, schemas
- WebSocket connection manager for real-time features
- Modular notification system with multiple channels
- Comprehensive error handling and validation
- Production-ready with Docker support
Technologies: FastAPI, WebSocket, SQLAlchemy, SQLite, Cryptography, Firebase, Pillow
- Implemented user authentication with JWT tokens
- Created comprehensive task management with CRUD operations
- Added category system for task organization
- Set up SQLite database with SQLAlchemy ORM
- Configured Alembic for database migrations
- Added API documentation with OpenAPI/Swagger
- Implemented proper authorization and user scoping
- Created health check and root endpoints
- Updated README with complete documentation
