GameEngine.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using TicTacToe.Core.GameNetworkInterfaces;

namespace TicTacToe.Core
{
    public class GameEngine
    {
        private ICommonGameNetworkControl _network;

        public GameEngine(ICommonGameNetworkControl network)
        {
            _network = network;
        }

        public string GetWinner(string[,] board)
        {
            return board[0,0];
        }

        public Guid Login(string userName, string password)
        {
            if (string.IsNullOrEmpty(userName))
            {
                throw new ArgumentException();
            }

            return _network.Login(userName, password);
        }
    }
}