# Todo App API

A simple Todo application API built with FastAPI and SQLite.

## Features

- ✅ Create, read, update, and delete todos
- ✅ Todo categories/tags for organization
- ✅ Due dates with overdue detection
- ✅ Advanced filtering (by category, completion status, overdue)
- ✅ SQLite database with SQLAlchemy ORM
- ✅ Database migrations with Alembic
- ✅ API documentation with Swagger UI
- ✅ Health check endpoint
- ✅ CORS enabled for all origins
- ✅ Input validation with Pydantic

## Quick Start

### Prerequisites

- Python 3.8+

### Installation

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

2. Run database migrations:
   ```bash
   alembic upgrade head
   ```

3. Start the development server:
   ```bash
   uvicorn main:app --host 0.0.0.0 --port 8000 --reload
   ```

   Or alternatively:
   ```bash
   python main.py
   ```

## API Endpoints

The API is available at `http://localhost:8000`

### Documentation
- **Swagger UI**: http://localhost:8000/docs
- **ReDoc**: http://localhost:8000/redoc
- **OpenAPI JSON**: http://localhost:8000/openapi.json

### Core Endpoints
- **GET** `/` - Root endpoint with project information
- **GET** `/health` - Health check endpoint

### Todo Endpoints
- **GET** `/api/v1/todos/` - List all todos (with pagination and filtering)
  - Query parameters: `skip`, `limit`, `category`, `completed`, `overdue_only`
- **POST** `/api/v1/todos/` - Create a new todo
- **GET** `/api/v1/todos/{todo_id}` - Get a specific todo
- **PUT** `/api/v1/todos/{todo_id}` - Update a specific todo
- **DELETE** `/api/v1/todos/{todo_id}` - Delete a specific todo
- **GET** `/api/v1/todos/categories/{category}` - Get all todos by category
- **GET** `/api/v1/todos/overdue` - Get all overdue todos

## Database

The application uses SQLite database stored at `/app/storage/db/db.sqlite`.

### Schema

**todos** table:
- `id` (Integer, Primary Key)
- `title` (String, Required)
- `description` (String, Optional)
- `completed` (Boolean, Default: False)
- `category` (String, Optional) - For organizing todos
- `due_date` (DateTime with timezone, Optional) - When the todo is due
- `created_at` (DateTime with timezone)
- `updated_at` (DateTime with timezone)

## Development

### Linting and Formatting

```bash
# Check and fix linting issues
ruff check . --fix

# Format code
ruff format .
```

### Database Migrations

```bash
# Create a new migration
alembic revision --autogenerate -m "Description of changes"

# Apply migrations
alembic upgrade head

# Downgrade
alembic downgrade -1
```

## Project Structure

```
├── app/
│   ├── api/
│   │   └── v1/
│   │       ├── api.py          # API router
│   │       └── todos.py        # Todo endpoints
│   ├── core/
│   │   └── config.py           # Configuration settings
│   ├── crud/
│   │   └── todo.py             # CRUD operations
│   ├── db/
│   │   ├── base.py             # SQLAlchemy base
│   │   ├── base_model.py       # Model imports
│   │   └── session.py          # Database session
│   ├── models/
│   │   └── todo.py             # SQLAlchemy models
│   └── schemas/
│       └── todo.py             # Pydantic schemas
├── migrations/                 # Alembic migrations
├── main.py                     # FastAPI application
└── requirements.txt            # Python dependencies
```