import os
from sqlalchemy import create_engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker

# 支持 MySQL, PostgreSQL
DATABASE_URL = os.getenv(
    DATABASE_URL,
    postgresql://postgres:postgres@localhost:5432/zodiac
)

# 数据库引擎配置
engine = create_engine(
    DATABASE_URL,
    pool_pre_ping=True,
    pool_size=10,
    max_overflow=20,
    pool_recycle=3600,  # 1小时回收连接
    pool_timeout=30,   # 获取连接超时30秒
    echo=False
)

SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)

Base = declarative_base()


def get_db():
    """获取数据库会话"""
    db = SessionLocal(expire_on_commit=False)
    try:
        yield db
    finally:
        db.close()