"""数据库会话依赖"""

from typing import AsyncGenerator
from sqlalchemy.ext.asyncio import AsyncSession, create_async_engine, async_sessionmaker
from app.config import settings

# 处理 sqlite 协议兼容
db_url = settings.DATABASE_URL
if db_url.startswith("sqlite://"):
    db_url = db_url.replace("sqlite://", "sqlite+aiosqlite://")

engine = create_async_engine(db_url, echo=False, pool_pre_ping=True)
async_session = async_sessionmaker(engine, class_=AsyncSession, expire_on_commit=False)


async def get_db() -> AsyncGenerator[AsyncSession, None]:
    async with async_session() as session:
        try:
            yield session
        finally:
            await session.close()


async def init_db():
    """Apply non-destructive schema upgrades before creating missing tables."""
    from importlib import import_module

    from app.models import Base

    migration = import_module("migrations.versions.20260803_reliability_monitoring")
    run_reliability_migration = migration.run_reliability_migration

    async with engine.begin() as conn:
        await conn.run_sync(run_reliability_migration)
        await conn.run_sync(Base.metadata.create_all)