"""Database configuration and session management."""
from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine

from app.core.config import settings

engine = create_async_engine(
    settings.DATABASE_URL,
    echo=settings.LOG_LEVEL == "DEBUG",
    future=True,
    pool_size=10,
    max_overflow=20,
    pool_pre_ping=True,
)

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


async def get_db() -> AsyncSession:
    """Dependency for FastAPI to get async DB session."""
    async with AsyncSessionLocal() as session:
        try:
            yield session
        finally:
            await session.close()


async def close_db() -> None:
    """Close database connections."""
    await engine.dispose()