"""
AmazingData 数据服务平台 - 认证依赖
"""

from fastapi import Depends, HTTPException, status
from fastapi.security import OAuth2PasswordBearer
from sqlalchemy.orm import Session
from backend.models.database import get_db
from backend.models.tables import User
from backend.auth.jwt_handler import decode_access_token
from typing import Optional

# OAuth2 密码流
oauth2_scheme = OAuth2PasswordBearer(tokenUrl="/api/v1/auth/login", auto_error=False)


async def get_current_user(
    token: Optional[str] = Depends(oauth2_scheme),
    db: Session = Depends(get_db)
) -> Optional[User]:
    """获取当前用户（可选认证）"""
    if not token:
        return None
    
    payload = decode_access_token(token)
    if payload is None:
        return None
    
    username: str = payload.get("sub")
    if username is None:
        return None
    
    user = db.query(User).filter(User.username == username).first()
    if user is None or not user.is_active:
        return None
    
    return user


async def get_current_active_user(
    current_user: Optional[User] = Depends(get_current_user)
) -> User:
    """获取当前活跃用户（需要认证）"""
    if current_user is None:
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Not authenticated",
            headers={"WWW-Authenticate": "Bearer"},
        )
    return current_user


async def require_admin(
    current_user: User = Depends(get_current_active_user)
) -> User:
    """要求管理员权限"""
    if current_user.role != "admin":
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="Admin privileges required"
        )
    return current_user