"""Database session management for the API gateway."""

from collections.abc import AsyncGenerator

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

from cartsnitch_api.config import settings

engine = create_async_engine(settings.database_url, echo=False)
async_session_factory = async_sessionmaker(engine, class_=AsyncSession, expire_on_commit=False)


async def get_db() -> AsyncGenerator[AsyncSession, None]:
    """FastAPI dependency that yields an async DB session."""
    async with async_session_factory() as session:
        yield session