from typing import Optional
from fastapi import Depends, HTTPException, status
from fastapi.security import OAuth2PasswordBearer
from jose import JWTError, jwt
from sqlalchemy.orm import Session
from app.config import settings
from app.database.database import get_db
from app.models.user import User
from app.schemas.auth import TokenData

# OAuth2密码流
oauth2_scheme = OAuth2PasswordBearer(tokenUrl="/api/auth/login")


def get_current_user(token: str = Depends(oauth2_scheme), db: Session = Depends(get_db)):
    """获取当前用户"""
    credentials_exception = HTTPException(
        status_code=status.HTTP_401_UNAUTHORIZED,
        detail="Could not validate credentials",
        headers={"WWW-Authenticate": "Bearer"},
    )
    try:
        payload = jwt.decode(token, settings.secret_key, algorithms=[settings.algorithm])
        username: str = payload.get("sub")
        if username is None:
            raise credentials_exception
        token_data = TokenData(username=username)
    except JWTError:
        raise credentials_exception
    user = db.query(User).filter(User.username == token_data.username).first()
    if user is None:
        raise credentials_exception
    return user


def get_current_active_user(current_user: User = Depends(get_current_user)):
    """获取当前活跃用户"""
    return current_user