# ===========================================
# 班级操行分管理系统 - 后端服务
# 
# 开发者: Canglan
# 联系方式: admin@sea-studio.top
# 版权归属: Sea Network Technology Studio
# 许可证: MIT License
# 
# 版权所有 © Sea Network Technology Studio
# ===========================================

from jose import jwt, JWTError
from datetime import datetime, timedelta
from typing import Optional, Dict, Any

from config import settings
from utils.logger import get_logger

logger = get_logger(__name__)


class JWTHandler:
    """JWT Token处理类"""
    
    @staticmethod
    def create_token(user_id: int, username: str, user_type: str, student_id: int = None, role: str = None) -> str:
        """
        创建JWT Token
        """
        payload = {
            'user_id': user_id,
            'username': username,
            'user_type': user_type,
            'student_id': student_id,
            'role': role,
            'exp': datetime.utcnow() + timedelta(minutes=settings.JWT_EXPIRE_MINUTES),
            'iat': datetime.utcnow(),
            'iss': settings.APP_NAME
        }
        
        token = jwt.encode(
            payload,
            settings.JWT_SECRET_KEY,
            algorithm=settings.JWT_ALGORITHM
        )
        return token
    
    @staticmethod
    def verify_token(token: str) -> Optional[Dict[str, Any]]:
        """
        验证JWT Token
        返回: 解码后的payload，失败返回None
        """
        try:
            payload = jwt.decode(
                token,
                settings.JWT_SECRET_KEY,
                algorithms=[settings.JWT_ALGORITHM],
                options={'verify_exp': True}
            )
            return payload
        except jwt.ExpiredSignatureError:
            logger.warning("JWT Token已过期")
            return None
        except jwt.JWTError as e:
            logger.warning(f"JWT Token验证失败: {e}")
            return None
    
    @staticmethod
    def get_user_id_from_token(token: str) -> Optional[int]:
        """从Token中获取用户ID"""
        payload = JWTHandler.verify_token(token)
        if payload:
            return payload.get('user_id')
        return None
    
    @staticmethod
    def get_user_type_from_token(token: str) -> Optional[str]:
        """从Token中获取用户类型"""
        payload = JWTHandler.verify_token(token)
        if payload:
            return payload.get('user_type')
        return None


jwt_handler = JWTHandler()