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

from app.core.config import settings

class Base(DeclarativeBase):
    pass

def _db_url() -> str:
    # w dockerze zwykle ustawiamy DATABASE_URL przez env, więc preferujemy settings.DATABASE_URL
    return settings.DATABASE_URL

engine = create_async_engine(_db_url(), future=True, echo=False)
SessionLocal = async_sessionmaker(engine, expire_on_commit=False, class_=AsyncSession)

async def init_db() -> None:
    from app.models import user, router, dashboard  # noqa
    async with engine.begin() as conn:
        await conn.run_sync(Base.metadata.create_all)

async def get_session() -> AsyncGenerator[AsyncSession, None]:
    async with SessionLocal() as session:
        yield session