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

engine = create_async_engine(settings.DATABASE_URL, echo=settings.DEBUG, pool_size=10, max_overflow=20)
async_session = async_sessionmaker(engine, class_=AsyncSession, expire_on_commit=False)


class Base(DeclarativeBase):
    pass


async def get_db():
    async with async_session() as session:
        try:
            yield session
        finally:
            await session.close()


async def init_db():
    from models.template import Template
    from models.paragraph import Paragraph
    from models.ai_model import AiModel
    from models.document import Document
    from models.generation_log import GenerationLog
    async with engine.begin() as conn:
        await conn.run_sync(Base.metadata.create_all)