using ConsoleChatServer;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading.Tasks;

namespace RockPaperScissorsServer
{
    internal class Server
    {
        // Attributes
        const String URL = "server.allcatsaregrey.co.uk";
        const int PORT = 19000;
        static String[] choices = { "rock", "paper", "scissors" };
        static Random r = new Random();
        static int index = r.Next(choices.Length);

        static void Main(string[] args)
        {
            // Declares networking variables
            IPAddress ip = IPSorter.FindIPv4Address(URL);
            TcpListener tcpListener = new TcpListener(ip, PORT);

            // Shows what IP and Port the server has been started on
            Console.WriteLine("Starting server...");
            tcpListener.Start();
            Console.WriteLine($"Started server on host {ip}:{PORT}");

            // Begin a loop to listen for incoming connection
            while (true)
            {
                // Accepts an incoming connection
                Socket client = tcpListener.AcceptSocket();

                // Receives the user's name
                byte[] nameBuffer = new byte[1024];
                int nameReceived = client.Receive(nameBuffer, SocketFlags.None);
                char[] nameChars = new char[nameReceived];
                Decoder d = Encoding.UTF8.GetDecoder();
                int nameCharLength = d.GetChars(nameBuffer, 0, nameReceived, nameChars, 0);
                String name = new string(nameChars);

                // Shows a client has connected
                Console.WriteLine($"{name} has connected.");

                // Receives user's choice
                byte[] clientChoiceBuffer = new byte[1024];
                int clientChoiceReceived = client.Receive(clientChoiceBuffer, SocketFlags.None);
                char[] choiceChars = new char[clientChoiceReceived];
                int choiceCharLength = d.GetChars(clientChoiceBuffer, 0, clientChoiceReceived, choiceChars, 0);
                String c = new string(choiceChars);

                // Shows the user's choice
                Console.WriteLine($"{name} has chosen {c}.");

                // Server chooses rock paper or scissors
                byte[] serverChoice = Encoding.ASCII.GetBytes(choices[index]);
                String s = Encoding.UTF8.GetString(serverChoice);
                Console.WriteLine($"Server has chosen: {s}");

                // Informs the client that the server has chosen
                byte[] serverChoiceBuffer = Encoding.ASCII.GetBytes(s);
                client.Send(serverChoiceBuffer, SocketFlags.None);

                // Determine winner
                if (c == s || s == c)
                {
                    Console.WriteLine("Tied.");
                }
                else if (c == "rock" && s == "scissors" ||
                         c == "paper" && s == "rock" ||
                         c == "scissors" && s == "paper")
                {
                    Console.WriteLine($"{name} has won.");
                }
                else
                {
                    Console.WriteLine("Server has won.");
                }

                Console.WriteLine("Press any key to exit.");
                Console.ReadKey();
            }
        }
    }
}