System Architecture
==================

This section provides a comprehensive overview of the AI-Writer system architecture, including component interactions, data flow, and design patterns.

.. toctree::
   :maxdepth: 2
   :caption: Architecture Documentation:

   overview
   components
   database_schema
   api_design
   security

Architecture Overview
-------------------

.. include:: overview.rst

Component Diagram
---------------

.. image:: diagrams/high_level_architecture.png
   :alt: AI-Writer High-Level Architecture Diagram
   :width: 800px

.. image:: diagrams/database_architecture.png
   :alt: AI-Writer Database Architecture Diagram
   :width: 800px

.. image:: diagrams/content_generation_workflow.png
   :alt: AI-Writer Content Generation Workflow Diagram
   :width: 800px

Key Components
------------

The AI-Writer platform consists of several key components:

1. **User Interface Layer**
   
   * Streamlit-based web interface
   * Component-based UI architecture
   * Responsive design for multiple devices

2. **Application Layer**
   
   * Content generation modules
   * AI provider integrations
   * Research and analysis tools
   * Analytics and reporting

3. **Data Layer**
   
   * Relational database (SQLite/PostgreSQL)
   * Vector database (ChromaDB)
   * File storage for generated content

4. **Integration Layer**
   
   * API endpoints for external integration
   * Authentication and authorization
   * Rate limiting and caching

Component Interactions
--------------------

The components interact through well-defined interfaces:

1. **UI to Application Layer**
   
   * Event-driven interaction
   * State management through Streamlit session state
   * Asynchronous processing for long-running tasks

2. **Application to Data Layer**
   
   * Repository pattern for data access
   * Transaction management
   * Connection pooling

3. **Application to External Services**
   
   * API client abstractions
   * Retry mechanisms
   * Circuit breakers for fault tolerance

Data Flow
--------

The typical data flow in the system:

1. User submits content generation request through UI
2. Application layer validates and processes the request
3. AI provider is called to generate content
4. Generated content is stored in the database
5. Content is returned to the UI for display and editing
6. Analytics data is collected and stored

Deployment Architecture
---------------------

AI-Writer supports multiple deployment models:

1. **Single-User Deployment**
   
   * Local installation
   * SQLite database
   * Local file storage

2. **Multi-User Deployment**
   
   * Docker-based deployment
   * PostgreSQL database
   * Shared file storage
   * Load balancing

3. **Cloud Deployment**
   
   * Kubernetes orchestration
   * Cloud database services
   * Object storage
   * Auto-scaling

Technology Stack
--------------

The AI-Writer platform is built on the following technologies:

1. **Frontend**
   
   * Streamlit
   * HTML/CSS/JavaScript
   * Plotly for visualizations

2. **Backend**
   
   * Python 3.9+
   * FastAPI for API endpoints
   * SQLAlchemy for ORM
   * ChromaDB for vector storage

3. **AI and ML**
   
   * OpenAI GPT models
   * Google Gemini
   * Hugging Face transformers
   * Sentence transformers for embeddings

4. **Infrastructure**
   
   * Docker
   * Docker Compose
   * Kubernetes (for cloud deployment)
   * GitHub Actions for CI/CD