"""
数据库连接和会话管理
"""
from sqlalchemy import create_engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker
import os
from pathlib import Path

from backend.config import DATA_DIR

# 确保数据目录存在
os.makedirs(DATA_DIR, exist_ok=True)

# 数据库URL
SQLALCHEMY_DATABASE_URL = f"sqlite:///{DATA_DIR}/lightstar.db"

# 创建引擎
engine = create_engine(
    SQLALCHEMY_DATABASE_URL, connect_args={"check_same_thread": False}
)

# 创建会话
SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)

# 基础模型类
Base = declarative_base()

# 依赖函数，获取数据库会话
def get_db():
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()