from fastapi import FastAPI, Depends
from fastapi.middleware.cors import CORSMiddleware
from sqlalchemy.orm import Session
from app.db.session import get_db, engine
from app.db.base import Base
from app.api.api import api_router

# Create database tables
Base.metadata.create_all(bind=engine)

# Initialize FastAPI app
app = FastAPI(
    title="Todo App API",
    description="A simple Todo application API built with FastAPI",
    version="1.0.0",
    docs_url="/docs",
    redoc_url="/redoc",
    openapi_url="/openapi.json"
)

# CORS configuration - allow all origins
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# Include API router
app.include_router(api_router, prefix="/api/v1")


@app.get("/")
async def root():
    """Base URL endpoint with app information and links"""
    return {
        "title": "Todo App API",
        "description": "A simple Todo application API built with FastAPI",
        "version": "1.0.0",
        "documentation": {
            "swagger_ui": "/docs",
            "redoc": "/redoc",
            "openapi_json": "/openapi.json"
        },
        "health_check": "/health"
    }


@app.get("/health")
async def health_check(db: Session = Depends(get_db)):
    """Health check endpoint that reports application health"""
    try:
        # Test database connection
        db.execute("SELECT 1")
        db_status = "healthy"
    except Exception as e:
        db_status = f"unhealthy: {str(e)}"
    
    return {
        "status": "healthy" if db_status == "healthy" else "unhealthy",
        "database": db_status,
        "service": "Todo App API",
        "version": "1.0.0"
    }