#!/usr/bin/env python3
# -*- coding: utf-8 -*-

"""
用户会话管理模块
用于存储和管理当前登录用户的信息
"""


class UserSession:
    """单例模式的用户会话管理器"""
    
    _instance = None
    _user_info = None
    
    def __new__(cls):
        if cls._instance is None:
            cls._instance = super(UserSession, cls).__new__(cls)
        return cls._instance
    
    @classmethod
    def set_user_info(cls, user_info):
        """
        设置当前登录用户信息
        
        Args:
            user_info (dict): 用户信息，包含 username, userid, role, auth 等字段
        """
        cls._user_info = user_info
        print(f"[UserSession] 用户登录成功: {user_info.get('username')} (角色: {user_info.get('role')})")
    
    @classmethod
    def get_user_info(cls):
        """
        获取当前登录用户信息
        
        Returns:
            dict: 用户信息，如果未登录则返回 None
        """
        return cls._user_info
    
    @classmethod
    def get_username(cls):
        """获取当前用户名"""
        return cls._user_info.get('username') if cls._user_info else None
    
    @classmethod
    def get_userid(cls):
        """获取当前用户ID"""
        return cls._user_info.get('userid') if cls._user_info else None
    
    @classmethod
    def get_role(cls):
        """获取当前用户角色"""
        return cls._user_info.get('role') if cls._user_info else None
    
    @classmethod
    def get_auth(cls):
        """获取当前用户权限"""
        return cls._user_info.get('auth') if cls._user_info else None
    
    @classmethod
    def is_logged_in(cls):
        """检查是否已登录"""
        return cls._user_info is not None
    
    @classmethod
    def is_super(cls):
        """检查是否为超级管理员"""
        return cls.get_role() == 'super'
    
    @classmethod
    def is_admin(cls):
        """检查是否为管理员"""
        role = cls.get_role()
        return role in ['super', 'admin']
    
    @classmethod
    def is_engineer(cls):
        """检查是否为工程师"""
        role = cls.get_role()
        return role in ['super', 'admin', 'engineer']
    
    @classmethod
    def clear(cls):
        """清除用户会话（登出）"""
        cls._user_info = None
        print("[UserSession] 用户已登出")