DocuLens/cline_docs/systemPatterns.md

System Patterns

Architecture Overview

The application follows a client-server architecture with containerized deployment and secure authentication:

Authentication System

• JSON file-based user management
• Secure password hashing with bcrypt
• Session-based authentication using Flask-Login
• Protected API routes with login_required decorator
• Remember me functionality for persistent sessions

Frontend (React)

• Single Page Application (SPA) architecture
• Authentication state management
• Protected route handling
• Component-based structure:
  • Login: User authentication interface
  • FileUpload: Handles file input and processing
  • FileList: Manages processed files
  • ModelSelector: AI model selection
  • Configurations: System settings and prompts
  • ProgressBar: Real-time processing feedback
  • Notifications: User feedback system
  • TxtToPdf: Document conversion utility
  • ImageDescription: Image analysis and description
  • ChangePassword: User password management

Backend (Flask)

• RESTful API architecture
• Modular design with separate concerns:
  • app.py: Main application and route handlers
  • models.py: Data models and AI model management
  • utils.py: Processing utilities and helpers

Key Technical Decisions

Background Processing

• Asynchronous job processing using threading
• Job tracking system with unique IDs
• Real-time progress updates via polling

File Management

• Secure file handling with unique naming
• Separate upload and output directories
• Support for multiple file formats

AI Integration

• Modular AI model system
• Support for multiple AI providers:
  • OpenAI
  • Gemini
  • Mistral
• Configurable prompts system
• Vision AI capabilities:
  • Base64 image encoding
  • MIME type detection
  • Proper Gemini Vision API formatting

OCR Processing

• Multiple processing modes:
  • Pure OCR (Tesseract)
  • Hybrid (OCR + AI)
  • Full AI OCR
• Page-by-page processing for large documents

Translation System

• Language management system
• Page-by-page translation
• Progress tracking per page

Configuration Management

• JSON-based configuration storage
• Import/export functionality
• Runtime model and prompt updates

Error Handling

• Comprehensive error catching
• User-friendly error messages
• Job cancellation support

Security Patterns

• Secure file uploads with sanitization
• CORS configuration with credentials support
• Environment-based configuration
• Password hashing and verification
• Session management and protection
• API route protection
• Authentication state persistence
• Secure cookie handling