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

namespace RatSockServer
{
    public class Program
    {
        //Both
        static string match = "test";

        static int port = 1337;

        //Server
        static IPAddress ipRecieve = IPAddress.Any;

        static TcpListener server = new TcpListener(ipRecieve, port);

        static List<Connection> connections = new List<Connection>();

        static void Main(string[] args)
        {
            server.Start();
            Thread checkCon_Thread = new Thread(checkNewConnection);
            Thread returnList_Thread = new Thread(returnList);
            checkCon_Thread.Start();
            returnList_Thread.Start();
        }

        static void checkNewConnection()
        {
            Connection connection = new Connection(null, server.AcceptTcpClient());
            if (connection.client != null)
            {
                Thread newCon_Thread = new Thread(()=>newConnection(connection));
                newCon_Thread.Start();
            }
            checkNewConnection();
        }

        static void returnList()
        {
            if (connections.Count != 0)
            {
                foreach (var a_con in connections)
                {
                    foreach (var a_str in a_con.connection)
                    {
                        Console.Write(a_str + "    ");
                    }
                    Console.WriteLine();
                }
            }
            else
            {
                Console.WriteLine("Waiting for Connections");
            }

            checkStates();
            Thread.Sleep(5000);
            Console.Clear();
            returnList();
        }

        static void checkStates()
        {
            try
            {
                foreach (var a_con in connections)
                {

                    sendData(a_con.client, "check_state");

                    string r_raw = recieveData(a_con.client);
                    string[] r_msg = null;
                    if (r_raw != null)
                    {
                        r_msg = r_raw.Split('_');
                        if (r_msg[0] == a_con.connection[1])
                        {
                            if (r_msg[1] != "alive")
                            {
                                connections.Remove(a_con);
                            }
                        }
                        else
                        {
                            connections.Remove(a_con);
                        }
                    }
                    else
                    {
                        connections.Remove(a_con);
                    }


                }
            }
            catch (InvalidOperationException)
            {

            }
        }

        static void newConnection(Connection connection)
        {
            string r_Match = recieveData(connection.client);
            if (r_Match == match)
            {
                sendData(connection.client, "accept");
                addToList(connection);
            }
        }

        static void addToList(Connection connection)
        {
            string[] t_connection = new string[3];
            string t_data = connections.Count+1 + "_" + recieveData(connection.client);
            t_connection =  t_data.Split('_');
            connection.connection = t_connection;
            connections.Add(connection);
        }

        static string recieveData(TcpClient client)
        {
            Byte[] bytes = new Byte[256];
            string data = null;

            // Get a stream object for reading and writing
            NetworkStream stream = client.GetStream();

            try
            {
                int i = stream.Read(bytes, 0, bytes.Length);
                data = System.Text.Encoding.ASCII.GetString(bytes, 0, i);
            }
            catch (IOException e)
            {
                data = null;
            }

            return data;
        }

        static void sendData(TcpClient client, string message)
        {
            // Translate the passed message into ASCII and store it as a Byte array.
            Byte[] data = System.Text.Encoding.ASCII.GetBytes(message);

            NetworkStream stream = client.GetStream();
            stream.Write(data, 0, data.Length);
        }
    }
}