from sqlalchemy.ext.asyncio import AsyncSession, create_async_engine, async_sessionmaker
from sqlalchemy.orm import DeclarativeBase
from app.config import settings

engine = create_async_engine(
    settings.DATABASE_URL,
    echo=settings.DEBUG,
    pool_size=10,
    max_overflow=20,
)

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


class Base(DeclarativeBase):
    pass


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


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