import uvicorn
import asyncio
from datetime import datetime
from fastapi import FastAPI, Depends
from fastapi.middleware.cors import CORSMiddleware
from sqlalchemy.orm import Session

from app.api.v1.api import api_router
from app.core.config import settings
from app.db.session import get_db
from app.core.background_tasks import task_manager

app = FastAPI(
    title=settings.PROJECT_NAME,
    description=settings.PROJECT_DESCRIPTION,
    version=settings.VERSION,
    openapi_url="/openapi.json",
    docs_url="/docs",
    redoc_url="/redoc",
)

# Set up CORS middleware
app.add_middleware(
    CORSMiddleware,
    allow_origins=settings.BACKEND_CORS_ORIGINS,
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# Include API router
app.include_router(api_router, prefix=settings.API_V1_STR)

# Root endpoint
@app.get("/")
async def root():
    return {
        "name": settings.PROJECT_NAME,
        "version": settings.VERSION,
        "documentation": "/docs",
        "health": "/health"
    }

# Health check endpoint
@app.get("/health", tags=["health"])
async def health_check(db: Session = Depends(get_db)):
    # Check if database is available
    try:
        # Execute a simple query
        db.execute("SELECT 1")
        db_status = "connected"
    except Exception as e:
        db_status = f"error: {str(e)}"
    
    return {
        "status": "ok",
        "version": settings.VERSION,
        "timestamp": datetime.utcnow().isoformat(),
        "database": db_status,
        "environment": "production" if not settings.DEBUG else "development",
    }

# Startup event
@app.on_event("startup")
async def startup_event():
    # Start background tasks
    asyncio.create_task(task_manager.start())

# Shutdown event
@app.on_event("shutdown")
async def shutdown_event():
    # Stop background tasks
    task_manager.stop()

if __name__ == "__main__":
    uvicorn.run("main:app", host="0.0.0.0", port=8000, reload=True)