using System;

public class Program

{

    public interface IAuthHandler 

    {

        string LogIn();

    }

    public class AuthHandler : IAuthHandler

    {

        public AuthHandler() 

        {

        }

        public string LogIn() 

        {

            return "accessToken";

        }

    }

    public class RetryingAuthHandler : IAuthHandler

    {

        private readonly IAuthHandler authHandler;

        public RetryingAuthHandler(IAuthHandler authHandler) 

        {

            this.authHandler = authHandler;

        }

        public string LogIn() 

        {

            var accessToken = string.Empty;

            while(string.IsNullOrEmpty(accessToken)) {

                accessToken = authHandler.LogIn();

            }

            return accessToken;

        }

    }

    public static void Main()

    {

        var authHandler = new RetryingAuthHandler(new AuthHandler());

        Console.Write(authHandler.LogIn());

    }

}