using System;
using System.Collections.Generic;
using System.Text;
using System.Net;
using System.Net.Sockets;
using System.IO;

namespace IvyBus
{
    class IvyUDPStreamV3
    {
        Socket socket;
        StreamReader input;
        StreamWriter output;
        byte[] buffer;
        MemoryStream out_stream;
        MemoryStream in_stream;

        /// the protocol version number
        internal const int PROCOCOLVERSION = 3;

        public IvyUDPStreamV3(Socket _socket)
        {
            socket = _socket;
            buffer = new byte[4096];
            in_stream = new MemoryStream(buffer);
            input = new StreamReader(in_stream, Encoding.ASCII);
            out_stream = new MemoryStream();
            output = new StreamWriter(out_stream, Encoding.ASCII);
        }
        /*
         * message Syntax:
         * this is a binary formated message use of network representation
         * 
         * message Format:
                protocol_version, TCP server port , lenAppId, appId,  lenAppNameId, appName
         */

        internal void receiveMsg(out IPEndPoint remote, out int version, out int port, out string appId, out string appName)
        {
            int len;
            IPEndPoint remoteEP = new IPEndPoint(IPAddress.Any, 0);
            EndPoint tempRemoteEP = (EndPoint)remoteEP;
            remoteEP = null;
            len = socket.ReceiveFrom(buffer, ref tempRemoteEP);
            remote = (IPEndPoint)tempRemoteEP;
            in_stream.Position = 0;
            version = 0; //TODO input.ReadUInt16();
            port = 0; //TODO input.ReadUInt16();
            int lenAppId = 0; //TODO input.ReadUInt16();
            appId = null; //TODO input.ReadChars(lenAppId);
            int lenAppName = 0; //TODO input.ReadUInt16();
            appName = null; //TODO new String(input.ReadChars(lenAppName));

        }

        internal void sendMsg(IPEndPoint EPhost, int port, string appId, string appName)
        {
            output.Write((ushort)IPAddress.HostToNetworkOrder((short)(PROCOCOLVERSION)));
            output.Write((ushort)IPAddress.HostToNetworkOrder((short)port));
            output.Write((ushort)IPAddress.HostToNetworkOrder((short)appId.Length));
            output.Write(appId.ToCharArray());
            output.Write((ushort)IPAddress.HostToNetworkOrder((short)appName.Length));
            output.Write(appName.ToCharArray());
            output.Flush();

            byte[] hellob = out_stream.GetBuffer();
            socket.SendTo(hellob, (int)out_stream.Length, 0, EPhost);
        }
        internal void Close()
        {
            socket.Close();
        }
    }
}