import sys
import time
import traceback
from contextlib import asynccontextmanager

import uvicorn
from fastapi import FastAPI, Request
from fastapi.middleware.cors import CORSMiddleware
from loguru import logger

from app.api.v1.api import api_router
from app.core.config import settings
from app.core.logging import setup_logging


@asynccontextmanager
async def lifespan(app: FastAPI):
    """
    Context manager for FastAPI app lifespan events.

    Startup and shutdown events run on application startup and shutdown.
    """
    # Setup logging on startup
    try:
        setup_logging()
        logger.info(f"Starting up {settings.PROJECT_NAME}")
        
        # Verify imports and application setup
        logger.info("Application initialized successfully")
        
        yield  # Run the application
        
        # Clean up resources on shutdown
        logger.info(f"Shutting down {settings.PROJECT_NAME}")
    except Exception as e:
        logger.error(f"Error during application startup: {e}")
        traceback.print_exc()
        sys.exit(1)


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


# Add middleware
@app.middleware("http")
async def add_process_time_header(request: Request, call_next):
    """
    Middleware to add X-Process-Time header to response.
    """
    start_time = time.time()
    response = await call_next(request)
    process_time = time.time() - start_time
    response.headers["X-Process-Time"] = str(process_time)

    # Log request details
    logger.info(
        f"{request.method} {request.url.path} "
        f"Status: {response.status_code} "
        f"Process Time: {process_time:.4f}s"
    )

    return response


# Set all CORS enabled origins
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],  # Allow all origins
    allow_credentials=True,
    allow_methods=["*"],  # Allow all methods
    allow_headers=["*"],  # Allow all headers
)

app.include_router(api_router, prefix=settings.API_V1_STR)


@app.get("/health", tags=["health"])
async def health_check():
    """
    Health check endpoint to verify the API is running.
    """
    logger.debug("Health check endpoint called")
    return {"status": "healthy"}


if __name__ == "__main__":
    try:
        logger.info("Starting server with uvicorn...")
        uvicorn.run("main:app", host="0.0.0.0", port=8000, reload=True)
    except Exception as e:
        logger.error(f"Failed to start server: {e}")
        traceback.print_exc()
        sys.exit(1)