from sqlalchemy.ext.asyncio import AsyncSession, create_async_engine
from sqlalchemy.orm import sessionmaker, declarative_base
from app.config import settings

async_engine = create_async_engine(
    settings.DATABASE_URL,
    echo=settings.DB_ECHO,
    pool_size=20,
    max_overflow=10,
    pool_pre_ping=True,
)

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

Base = declarative_base()


async def get_db() -> AsyncSession:
    async with AsyncSessionLocal() as session:
        try:
            yield session
            await session.commit()
        except Exception:
            await session.rollback()
            raise
        finally:
            await session.close()