"""SQLAlchemy 异步数据库配置"""

from contextlib import asynccontextmanager
from sqlalchemy.ext.asyncio import create_async_engine, AsyncSession, async_sessionmaker
from app.config import settings

# SQLite 异步需要 aiosqlite
db_url = settings.database_url.replace("sqlite:///", "sqlite+aiosqlite:///")
engine = create_async_engine(db_url, echo=False)
async_session = async_sessionmaker(engine, class_=AsyncSession, expire_on_commit=False)


@asynccontextmanager
async def get_db():
    session = async_session()
    try:
        yield session
    finally:
        await session.close()


async def init_db():
    """创建所有表，并补充新增列"""
    from app.db.tables import metadata
    async with engine.begin() as conn:
        await conn.run_sync(metadata.create_all)
        # 补充新增列（SQLite ALTER TABLE ADD COLUMN，已存在会忽略）
        for col_sql in [
            "ALTER TABLE recommendations ADD COLUMN position_score REAL",
            "ALTER TABLE recommendations ADD COLUMN valuation_score REAL",
            "ALTER TABLE recommendations ADD COLUMN llm_analysis TEXT DEFAULT ''",
            "ALTER TABLE recommendations ADD COLUMN strategy TEXT DEFAULT 'momentum'",
            "ALTER TABLE recommendations ADD COLUMN llm_score REAL",
            "ALTER TABLE market_temperature ADD COLUMN max_streak INTEGER",
            "ALTER TABLE market_temperature ADD COLUMN broken_rate REAL",
            "ALTER TABLE recommendations ADD COLUMN entry_signal_type TEXT DEFAULT 'none'",
            "ALTER TABLE sector_heat ADD COLUMN stage TEXT",
            "ALTER TABLE sector_heat ADD COLUMN days_continuous INTEGER",
            "ALTER TABLE sector_heat ADD COLUMN member_count INTEGER",
            "ALTER TABLE sector_heat ADD COLUMN leading_stocks TEXT",
            "ALTER TABLE sector_heat ADD COLUMN pct_trend TEXT",
            "ALTER TABLE sector_heat ADD COLUMN turnover_avg REAL",
            "ALTER TABLE sector_heat ADD COLUMN main_force_ratio REAL",
        ]:
            try:
                await conn.execute(
                    __import__("sqlalchemy").text(col_sql)
                )
            except Exception:
                pass  # 列已存在，忽略