from sqlalchemy.ext.asyncio import create_async_engine, AsyncSession
from sqlalchemy.orm import sessionmaker
from sqlalchemy.exc import SQLAlchemyError
from config.settings import settings
import logging
from contextlib import asynccontextmanager

logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)

DATABASE_URL = settings.database_url

# Configuration optimisée du moteur
engine = create_async_engine(
    DATABASE_URL,
    echo=True,
    pool_size=5,
    max_overflow=10,
    pool_timeout=30,
    pool_recycle=1800,
    pool_pre_ping=True
)

AsyncSessionLocal = sessionmaker(
    engine,
    class_=AsyncSession,
    expire_on_commit=False,
    autocommit=False,
    autoflush=False
)

@asynccontextmanager
async def get_db():
    session = AsyncSessionLocal()
    try:
        yield session
        await session.commit()
    except SQLAlchemyError as e:
        await session.rollback()
        logger.error(f"Database error: {str(e)}")
        raise
    finally:
        await session.close()

async def init_db():
    from models.db import metadata 
    try:
        async with engine.begin() as conn:
            await conn.run_sync(metadata.create_all)
        logger.info("Database tables created successfully.")
    except Exception as e:
        logger.error(f"Error creating database tables: {str(e)}")
        raise