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

namespace Chop
{
    public class ClientManager
    {
        private int mMaxClients;
        private Hashtable mClients;
        private Thread PingPong;

        private string lastConnectionIP; // For anti-ddos

        internal void Init(int MaxClients)
        {
            this.mClients = new Hashtable();
            this.mMaxClients = MaxClients;

            PingPong = new Thread(new ThreadStart(Pong));
            PingPong.Name = "PingPong";
            PingPong.Start();
        }

        internal void Destroy()
        {
            Hashtable Copy = (Hashtable)mClients.Clone();
            foreach (GameClient client in Copy.Values)
            {
                RemoveClient(client.ID);
            }
        }

        internal GameClient GetClient(string IP)
        {
            foreach (GameClient client in mClients.Values)
                if (client.IP == IP)
                    return client;
            return null;
        }
        internal GameClient GetClient(uint ID)
        {
            foreach (GameClient client in mClients.Values)
                if (client.ID == ID)
                    return client;
            return null;
        }

        private uint GenerateClientID()
        {
            uint i = 0;
            while (mClients.Contains(i))
                i++;
            return i;
        }
        internal void AddClient(Socket socket)
        {
            if (mClients.Count >= mMaxClients || (lastConnectionIP == GetIP(socket) && Core.Config.GetBoolean("socket.ddos.block")))
            {
                socket.Shutdown(SocketShutdown.Both);
                socket.Close();
                socket.Dispose();
            }
            else
            {
                if (Core.Config.GetBoolean("socket.ddos.block"))
                    lastConnectionIP = GetIP(socket);

                GameClient oldClient = GetClient(GetIP(socket));
                if (oldClient != null)
                {
                    RemoveClient(oldClient.ID);
                }

                GameClient Client = new GameClient(GenerateClientID(), socket);
                mClients.Add(Client.ID, Client);

                Console.WriteLine("Accepted new client [" + Client.ID + "] from " + Client.IP);

                Response WelcomeMessage = new Response(0); // "@@", say hello
                Client.SendMessage(WelcomeMessage);
            }
        }
        internal void RemoveClient(uint ID)
        {
            try
            {
                GameClient Client = GetClient(ID);

                if (Client != null)
                {
                    Console.WriteLine("Disconnected client [" + ID + "] from " + Client.IP);
                    Client.Destroy();
                    mClients.Remove(ID);
                }
            }
            catch (Exception) { }
        }
        public string GetIP(Socket socket)
        {
            return socket.RemoteEndPoint.ToString().Split(':')[0];
        }
        private void Pong()
        {
            int wait = Core.Config.GetInt("managers.client.pong.interval");

            while (true)
            {
                foreach(GameClient client in mClients.Values)
                    if (client.Ponged)
                    {
                        client.Ponged = false;

                        Response r = new Response(50); // "@r"
                        client.SendMessage(r);
                    }
                    else
                        RemoveClient(client.ID);

                Thread.Sleep(wait);
            }
        }
    }
}