"""数据库初始化"""
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker, declarative_base
from config import DATABASE_URL

# check_same_thread 仅 SQLite 需要
connect_args = {"check_same_thread": False} if DATABASE_URL.startswith("sqlite") else {}
engine = create_engine(DATABASE_URL, connect_args=connect_args)
SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
Base = declarative_base()


def get_db():
    """获取数据库会话（FastAPI 依赖注入用）"""
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()