from collections.abc import AsyncGenerator
from contextlib import asynccontextmanager

import socketio
from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware

from app.api import api_router
from app.core.database import init_db
from app.core.logging import get_logger, setup_logging
from app.middleware.logging import LoggingMiddleware
from app.services.extraction_processor import extraction_processor
from app.services.socket import socket_manager


@asynccontextmanager
async def lifespan(_app: FastAPI) -> AsyncGenerator[None, None]:
    """Application lifespan context manager for setup and teardown."""
    setup_logging()
    logger = get_logger(__name__)
    logger.info("Starting application")

    await init_db()
    logger.info("Database initialized")

    # Start the extraction processor
    await extraction_processor.start()
    logger.info("Extraction processor started")

    yield

    logger.info("Shutting down application")
    
    # Stop the extraction processor
    await extraction_processor.stop()
    logger.info("Extraction processor stopped")


def create_app():
    """Create and configure the FastAPI application."""
    app = FastAPI(lifespan=lifespan)

    # Add CORS middleware
    app.add_middleware(
        CORSMiddleware,
        allow_origins=["http://localhost:8001"],
        allow_credentials=True,
        allow_methods=["*"],
        allow_headers=["*"],
    )

    app.add_middleware(LoggingMiddleware)

    # Include API routes
    app.include_router(api_router)

    # Create Socket.IO app with fallback to FastAPI app
    return socketio.ASGIApp(socket_manager.sio, app)


app = create_app()