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

DATABASE_URL = os.getenv("DATABASE_URL", "sqlite+aiosqlite:///./xdl.db")

engine = create_async_engine(DATABASE_URL, echo=False)
async_session = async_sessionmaker(engine, class_=AsyncSession, expire_on_commit=False)


class Base(DeclarativeBase):
    pass


async def get_db():
    async with async_session() as session:
        yield session


async def init_db():
    async with engine.begin() as conn:
        await conn.run_sync(Base.metadata.create_all)
        # Ensure indexes exist on already-created tables (idempotent)
        from sqlalchemy import text
        await conn.execute(text(
            "CREATE INDEX IF NOT EXISTS ix_video_url_format_id ON videos (url, format_id)"
        ))
        await conn.execute(text(
            "CREATE INDEX IF NOT EXISTS ix_download_logs_video_id ON download_logs (video_id)"
        ))
        await conn.execute(text(
            "CREATE INDEX IF NOT EXISTS ix_download_logs_downloaded_at ON download_logs (downloaded_at)"
        ))
        # Migrate: add geo columns to existing download_logs table (idempotent)
        for col_def in [
            "ALTER TABLE download_logs ADD COLUMN country_code VARCHAR(8) DEFAULT ''",
            "ALTER TABLE download_logs ADD COLUMN country VARCHAR(128) DEFAULT ''",
            "ALTER TABLE download_logs ADD COLUMN city VARCHAR(128) DEFAULT ''",
        ]:
            try:
                await conn.execute(text(col_def))
            except Exception:
                pass  # Column already exists

        # Seed default cleanup settings (only if not already set)
        defaults = {
            "cleanup_enabled": "true",
            "cleanup_retention_minutes": "10080",   # 7 days
            "cleanup_storage_limit_pct": "80",
            "cleanup_last_run": "",
            "cleanup_last_result": "",
        }
        for k, v in defaults.items():
            await conn.execute(text(
                "INSERT OR IGNORE INTO app_settings (key, value, updated_at) VALUES (:k, :v, datetime('now'))"
            ), {"k": k, "v": v})