from collections.abc import AsyncGenerator

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

from .config import get_settings

settings = get_settings()

engine = create_async_engine(
    settings.database_url,
    echo=settings.debug,
    pool_pre_ping=True,
    pool_size=10,
    max_overflow=20,
    pool_recycle=3600,
)

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


class Base(DeclarativeBase):
    pass


async def get_db() -> AsyncGenerator[AsyncSession, None]:
    async with async_session_factory() as session:
        try:
            yield session
        finally:
            await session.close()