# Delphi Database

A legal case management database application built with FastAPI, SQLAlchemy, and modern Python practices.

## Database Configuration

The application uses SQLAlchemy ORM with support for multiple database backends.

### Environment Variables

Configure your database connection using environment variables:

```bash
# SQLite (default for development)
DATABASE_URL=sqlite:///./delphi.db

# PostgreSQL (production example)
DATABASE_URL=postgresql://username:password@localhost:5432/delphi_db

# MySQL (alternative)
DATABASE_URL=mysql://username:password@localhost:3306/delphi_db
```

### Database Models

The application includes the following models:

- **User**: Authentication and user management
- **Client**: Client/contact information
- **Phone**: Phone numbers linked to clients
- **Case**: Legal cases with unique file numbers
- **Transaction**: Financial transactions for cases
- **Document**: Case-related documents
- **Payment**: Payment records for cases

### Database Connection Management

The `app/database.py` module provides:

- **Database engine configuration** with connection pooling and error handling
- **Session management** with automatic cleanup via FastAPI dependency injection
- **Table creation utilities** for application startup
- **Connection health monitoring** via the `/health` endpoint

### Usage Examples

#### Basic Application Startup

```python
from fastapi import FastAPI, Depends
from sqlalchemy.orm import Session
from app.database import get_db

@app.get("/clients/")
async def get_clients(db: Session = Depends(get_db)):
    # Use the database session
    return db.query(Client).all()
```

#### Health Check

The `/health` endpoint verifies database connectivity:

```bash
curl http://localhost:8000/health
# {"status": "healthy", "database": "connected", "users": 0}
```

## Getting Started

1. Install dependencies:
   ```bash
   pip install -r requirements.txt
   ```

2. Configure your database in environment variables (see `.env` file)

3. Run the application:
   ```bash
   uvicorn app.main:app --reload
   ```

4. Access the API at `http://localhost:8000`

## Project Structure

```
app/
├── main.py          # FastAPI application entry point
├── database.py      # Database configuration and session management
├── models.py        # SQLAlchemy models
└── templates/       # HTML templates
```

## Development

- Database tables are automatically created on application startup
- Use the health check endpoint to verify database connectivity
- Environment variables control database configuration (never hardcode credentials)
- SQLAlchemy provides type-safe database operations with relationship management