"""
database/session.py - Async SQLAlchemy session management for NeonDB PostgreSQL
"""
from sqlalchemy.ext.asyncio import AsyncSession, create_async_engine, async_sessionmaker
from sqlalchemy.orm import DeclarativeBase
from config import settings
from loguru import logger

engine = create_async_engine(
    settings.DATABASE_URL,
    echo=settings.DB_ECHO,
    pool_size=10,
    max_overflow=20,
    pool_pre_ping=True,
    connect_args={"ssl": "require"},
)

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


class Base(DeclarativeBase):
    pass


async def get_db() -> AsyncSession:
    async with AsyncSessionLocal() as session:
        try:
            yield session
            await session.commit()
        except Exception:
            await session.rollback()
            raise
        finally:
            await session.close()


async def create_tables():
    """Create all tables on startup."""
    async with engine.begin() as conn:
        from database.models import Person, Event  # noqa: F401
        await conn.run_sync(Base.metadata.create_all)
    logger.info("✅ Database tables ensured.")