"""FastAPI 依赖：数据库 session、当前登录用户。"""
from fastapi import Depends, HTTPException, status
from fastapi.security import OAuth2PasswordBearer
from sqlalchemy.ext.asyncio import AsyncSession

from app.db import get_db
from app.models.user import User
from app.services.security import decode_access_token

oauth2_scheme = OAuth2PasswordBearer(tokenUrl="/api/auth/login")

_CRED_EXC = HTTPException(
    status_code=status.HTTP_401_UNAUTHORIZED,
    detail="无效或过期的凭证",
    headers={"WWW-Authenticate": "Bearer"},
)


async def get_current_user(
    token: str = Depends(oauth2_scheme),
    db: AsyncSession = Depends(get_db),
) -> User:
    user_id = decode_access_token(token)
    if not user_id:
        raise _CRED_EXC
    user = await db.get(User, user_id)
    if user is None or not user.is_active:
        raise _CRED_EXC
    return user