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

from app.config import get_settings

logger = logging.getLogger(f'{__name__}.session')

settings = get_settings()

# Create async engine
engine = create_async_engine(
    settings.database_url,
    echo=settings.debug,
    pool_size=settings.db_pool_size,
    max_overflow=settings.db_max_overflow,
)

# Create session factory
AsyncSessionLocal = async_sessionmaker(
    engine,
    class_=AsyncSession,
    expire_on_commit=False,
    autocommit=False,
    autoflush=False,
)

# Base class for models
Base = declarative_base()


async def init_db() -> None:
    """Initialize database tables"""
    async with engine.begin() as conn:
        # Import all models here to ensure they're registered
        from app.models import db_models

        # Create tables
        await conn.run_sync(Base.metadata.create_all)
        logger.info("Database tables created")


async def get_session() -> AsyncGenerator[AsyncSession, None]:
    """Dependency for getting database session"""
    async with AsyncSessionLocal() as session:
        try:
            yield session
            await session.commit()
        except Exception:
            await session.rollback()
            raise
        finally:
            await session.close()