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

# Create async engine with psycopg
engine = create_async_engine(
    settings.database_url,
    echo=settings.database_echo,
    future=True,
    pool_pre_ping=True,  # Verify connections before using them
    pool_size=20,
    max_overflow=10
)

# 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 get_db():
    """Dependency to get database session"""
    async with AsyncSessionLocal() as session:
        try:
            yield session
            await session.commit()
        except Exception:
            await session.rollback()
            raise
        finally:
            await session.close()


async def init_db():
    """Initialize database - create all tables"""
    async with engine.begin() as conn:
        await conn.run_sync(Base.metadata.create_all)
    print("✓ Database tables initialized")


async def close_db():
    """Close database connections"""
    await engine.dispose()
    print("✓ Database connections closed")