from sqlalchemy.ext.asyncio import AsyncSession, create_async_engine, async_sessionmaker
from sqlalchemy.orm import declarative_base

from app.config import settings

_url = settings.database_url
# SQLite for local dev — no pool settings
if _url.startswith("sqlite"):
    engine = create_async_engine(_url, echo=False, connect_args={"check_same_thread": False})
else:
    engine = create_async_engine(_url, echo=False, pool_pre_ping=True, pool_size=10, max_overflow=20)

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

Base = declarative_base()


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