using System.Collections.Generic;

public enum UserRole
{
	Admin,
	User
}

public class CurrentUser
{
	public string Username { get; set; }
	public UserRole Role { get; set; }
}

/// <summary>
/// 扩展认证服务接口，支持用户管理功能
/// </summary>
public interface IAuthenticationService : IService
{
	bool Login(string username, string password, out UserRole role);
	void Logout();
	bool IsLoggedIn { get; }
	string CurrentUsername { get; }
	UserRole CurrentRole { get; }
	CurrentUser CurrentUser { get; }
	
	// 用户管理功能
	bool AddUser(string username, string password, UserRole role);
	bool RemoveUser(string username);
	bool ChangePassword(string username, string oldPassword, string newPassword);
	bool ValidCurrentPassword(string password);
	List<UserInfo> GetAllUsers();
	
	// 用户统计信息
	int GetUserCount();
	int GetMaxUserCount();
}