from sqlalchemy.ext.asyncio import create_async_engine, async_sessionmaker, AsyncSession
from sqlalchemy.orm import declarative_base
from packages.core.config import settings

# 创建异步数据库引擎
engine_kwargs = {
    "echo": False,
    "future": True,
}
if not settings.DATABASE_URL.startswith("sqlite"):
    engine_kwargs["pool_size"] = 20
    engine_kwargs["max_overflow"] = 10

engine = create_async_engine(
    settings.DATABASE_URL,
    **engine_kwargs
)

# 创建异步 Session 工厂
AsyncSessionLocal = async_sessionmaker(
    bind=engine,
    class_=AsyncSession,
    expire_on_commit=False,
    autoflush=False
)

# ORM 基类
Base = declarative_base()

# 数据库会话依赖注入函数
async def get_db_session():
    async with AsyncSessionLocal() as session:
        try:
            yield session
        finally:
            await session.close()


async def get_db():
    async with AsyncSessionLocal() as session:
        try:
            yield session
        finally:
            await session.close()