from typing import AsyncGenerator

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

from app.core.config import settings

engine = create_async_engine(
    settings.DATABASE_URL,
    echo=settings.DEBUG if hasattr(settings, "DEBUG") else False,
)

async_session_factory = async_sessionmaker(engine, class_=AsyncSession, expire_on_commit=False)

Base = declarative_base()


async def get_db() -> AsyncGenerator[AsyncSession, None]:
    async with async_session_factory() as session:
        try:
            yield session
            await session.commit()
        except Exception:
            await session.rollback()
            raise


async def init_db():
    import app.models.user  # noqa: F401
    import app.models.gpu_cluster  # noqa: F401
    import app.models.task  # noqa: F401
    import app.models.datasource  # noqa: F401

    async with engine.begin() as conn:
        await conn.run_sync(Base.metadata.create_all)