from sqlalchemy.ext.asyncio import create_async_engine, AsyncSession, async_sessionmaker
from sqlalchemy.orm import DeclarativeBase
from sqlalchemy import text
from .config import settings

engine = create_async_engine(
    settings.database_url,
    echo=False,
    pool_size=20,
    max_overflow=10,
    pool_pre_ping=True,
)

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


class Base(DeclarativeBase):
    pass


async def get_db():
    async with AsyncSessionLocal() as session:
        try:
            yield session
        finally:
            await session.close()


async def init_db():
    from .models import provider, channel, user, epg, custom_category, log, notification, jellyfin, stream_event  # noqa: ensure all models imported
    from .models.provider import ProviderUrl  # noqa: ensure ProviderUrl is registered
    async with engine.begin() as conn:
        await conn.run_sync(Base.metadata.create_all)
        # Migrate: add pump_duration_secs column if it doesn't exist yet
        try:
            await conn.execute(text(
                "ALTER TABLE stream_events ADD COLUMN pump_duration_secs INTEGER"
            ))
        except Exception:
            pass  # column already exists
        # Migrate: create provider_urls entries from existing base_url if not already done
        await conn.execute(text("""
            INSERT INTO provider_urls (provider_account_id, url, priority, is_active, status)
            SELECT id, base_url, 0, true, 'unknown'
            FROM provider_accounts
            WHERE id NOT IN (SELECT DISTINCT provider_account_id FROM provider_urls WHERE provider_account_id IS NOT NULL)
            ON CONFLICT DO NOTHING
        """))
        await conn.commit()