Form1.cs

using System;
using System.Drawing;
using System.Collections;
using System.Windows.Forms;
using System.Data;
using System.Net;
using System.Net.Sockets;

namespace SmartDeviceGUIClient {
        public class Form1 : System.Windows.Forms.Form {
                private System.Windows.Forms.Label label1;
                private System.Windows.Forms.Button button1;
                private System.Windows.Forms.TextBox textBox1;
                private System.Windows.Forms.Button button2;
                private System.Windows.Forms.Button button3;
                private System.Windows.Forms.TextBox textBox2;
                private System.Windows.Forms.Label label2;
                private System.Windows.Forms.MainMenu mainMenu1;

                public Form1() {
                        //
                        // Required for Windows Form Designer support
                        //
                        InitializeComponent();

                        //
                        // TODO: Add any constructor code after InitializeComponent call
                        //
                }
                protected override void Dispose( bool disposing ) {
                        base.Dispose( disposing );
                }
                #region Windows Form Designer generated code
                private void InitializeComponent() {
                        this.mainMenu1 = new System.Windows.Forms.MainMenu();
                        this.label1 = new System.Windows.Forms.Label();
                        this.button1 = new System.Windows.Forms.Button();
                        this.textBox1 = new System.Windows.Forms.TextBox();
                        this.button2 = new System.Windows.Forms.Button();
                        this.button3 = new System.Windows.Forms.Button();
                        this.textBox2 = new System.Windows.Forms.TextBox();
                        this.label2 = new System.Windows.Forms.Label();
                        // 
                        // label1
                        // 
                        this.label1.Size = new System.Drawing.Size(240, 20);
                        this.label1.Text = "Welcome to GPRSWeb Mobile Client";
                        // 
                        // button1
                        // 
                        this.button1.Location = new System.Drawing.Point(8, 32);
                        this.button1.Size = new System.Drawing.Size(64, 24);
                        this.button1.Text = "button1";
                        this.button1.Click += new System.EventHandler(this.button1_Click);
                        // 
                        // textBox1
                        // 
                        this.textBox1.AcceptsReturn = true;
                        this.textBox1.Location = new System.Drawing.Point(8, 96);
                        this.textBox1.Multiline = true;
                        this.textBox1.ReadOnly = true;
                        this.textBox1.ScrollBars = System.Windows.Forms.ScrollBars.Both;
                        this.textBox1.Size = new System.Drawing.Size(224, 168);
                        this.textBox1.Text = "textBox1";
                        this.textBox1.TextChanged += new System.EventHandler(this.textBox1_TextChanged);
                        // 
                        // button2
                        // 
                        this.button2.Location = new System.Drawing.Point(80, 32);
                        this.button2.Size = new System.Drawing.Size(80, 24);
                        this.button2.Text = "Show Text";
                        this.button2.Click += new System.EventHandler(this.button2_Click);
                        // 
                        // button3
                        // 
                        this.button3.Location = new System.Drawing.Point(168, 32);
                        this.button3.Size = new System.Drawing.Size(64, 24);
                        this.button3.Text = "button3";
                        this.button3.Click += new System.EventHandler(this.button3_Click);
                        // 
                        // textBox2
                        // 
                        this.textBox2.Location = new System.Drawing.Point(64, 64);
                        this.textBox2.Size = new System.Drawing.Size(168, 20);
                        this.textBox2.Text = "textBox2";
                        // 
                        // label2
                        // 
                        this.label2.Location = new System.Drawing.Point(8, 64);
                        this.label2.Size = new System.Drawing.Size(48, 20);
                        this.label2.Text = "This IP:";
                        this.label2.ParentChanged += new System.EventHandler(this.label2_ParentChanged);
                        // 
                        // Form1
                        // 
                        this.ClientSize = new System.Drawing.Size(240, 270);
                        this.Controls.Add(this.label2);
                        this.Controls.Add(this.textBox2);
                        this.Controls.Add(this.button3);
                        this.Controls.Add(this.button2);
                        this.Controls.Add(this.textBox1);
                        this.Controls.Add(this.button1);
                        this.Controls.Add(this.label1);
                        this.Menu = this.mainMenu1;
                        this.Text = "Form1";
                        this.Load += new System.EventHandler(this.Form1_Load);

                }
                #endregion


                static void Main() {
                        Application.Run(new Form1());
                }

                private void Form1_Load(object sender, System.EventArgs e) {
                        label1.TextAlign = ContentAlignment.TopCenter;
                }

                StackInterface stackInf;

                private void button1_Click(object sender, System.EventArgs e) {
                        //                              ClientControl clientControl = null;
                        //                              Console myConsole = new Console(textBox1);
                        stackInf = new StackInterface();
                        SegmentReceiver rx = new SegmentReceiver(stackInf);
                        SegmentTransmitter tx = new SegmentTransmitter();
                        rx.Start();
                        //                              try {
                        //                                      myConsole.WriteLine("GPRSWeb Console Client {0} (Build {1})\r\n\r\n", System.Reflection.Assembly.GetExecutingAssembly().GetName().Version.ToString(2), System.Reflection.Assembly.GetExecutingAssembly().GetName().Version.Build);
                        //                                      try {
                        //                                              clientControl = new ClientControl();
                        //                                      } catch (MissingMethodException missex) {
                        //                                              myConsole.WriteLine(missex.ToString());
                        //                                      }
                        //                                      clientControl.Start();
                        //                                      clientControl.Join(); // *** I'm not sure if this should be here...
                        //                              } catch (ApplicationException appEx) {
                        //                                      myConsole.WriteLine("*** Application Error ***\n{0}", appEx);
                        //                                      myConsole.WriteLine("+++ ATTEMPTING STOP +++");
                        //                                      if (clientControl != null) { clientControl.Stop(); }
                        //                              }
                        //                              myConsole.Write("Press any key to close...");
                        //                              myConsole.ReadLine();
                }

                        private void textBox1_TextChanged(object sender, System.EventArgs e) {
                
                        }

                private void button2_Click(object sender, System.EventArgs e) {
                        textBox1.Text = stackInf.strWriter.ToString();
                }

                private void button3_Click(object sender, System.EventArgs e) {
                        textBox1.Text += "\r\nSend button Pressed";
                        SendTQE();
                }

                UdpClient myUDP = null;
                private void SendTQE() {
                        myUDP = new UdpClient(new IPEndPoint(IPAddress.Parse(textBox2.Text), 12346));
                        Segment workingSegment = new Segment();
                        uint sequenceOffset = 0;
                        //RateInfo rateInfo = null;
                        /* Gathering Data For Headers */
                        bool isAckable = false;
                        AckInfo ackInfo = null;
                        workingSegment.Headers = new SegmentHeaders();
                        NackInfo nackInfo = null;
                        uint seqNum = 1;
                        bool isResynch = false;
                        
                        // TODO: Add Try / Catch here (looking up IP address of destination)
                        IPAddress currentDestination = IPAddress.Parse("131.111.251.46");

                        /* Assign Segment Data */
                        workingSegment.Data = null;

                        /* Fill in Segment Headers */
                        /* Initial Flags */
                        workingSegment.Headers.IsAckable = isAckable;
                        workingSegment.Headers.IsResynch = isResynch;
                        workingSegment.Headers.IsFirstInMessage = true;
                        workingSegment.Headers.IsLastInMessage = true;

                        /* Source Device ID and Sequence Number */
                        workingSegment.Headers.SourceDeviceID = 1;
                        workingSegment.Headers.SequenceNumber = seqNum;

                        /* ACKs and NACKs */
                        if (ackInfo == null) { // no ACKs today
                                workingSegment.Headers.ClearAck();
                        } else { // ACK that segment!
                                workingSegment.Headers.SetAck(ackInfo);
                        }
                        if (nackInfo == null) { // no NACKs today
                                workingSegment.Headers.ClearNACKStatus();
                        } else { // NACK that segment!
                                workingSegment.Headers.SetNACKStatus(nackInfo);
                //              Console.WriteLine("Adding NACK on outgoing segment #{0} for retrans of seg #{1}", workingSegment.Headers.SequenceNumber, nackInfo.SequenceNumber);
                        }
                                
                        

                        /* Time stamp and send */
                        workingSegment.Headers.TimeSent = DateTime.Now.ToUniversalTime();
                        tempSend(workingSegment, currentDestination);
                        
                        
                }

                public void tempSend(Segment targetSegment, IPAddress destination) {
                        byte[] datagram = targetSegment.ToByteArray();
                        myUDP.Send(datagram, datagram.Length, new IPEndPoint(destination, 30481));
                        MessageBox.Show("Sent segment");
                }

                private void label2_ParentChanged(object sender, System.EventArgs e) {
                
                }
                }

        internal class Console {
                TextBox textOut; 
                public Console(TextBox textOut) {
                        this.textOut = textOut;
                }
                public void WriteLine(string s) { 
                        WriteLine(s, null); 
                }
                public void WriteLine(string s, params object[] objs) {
                        textOut.Text += String.Format(s, objs) + "\r\n";
                }
                public void ReadLine() {}
                public void Write(string s) { Write(s, null); }
                public void Write(string s, params object[] objs) {
                        textOut.Text += String.Format(s, objs);
                }
        }

        public class StackInterface {
                public MessageLogger msgLog;
                public System.IO.StringWriter strWriter;
                public StackSettings settings;
                public StackInterface() {
                        strWriter = new System.IO.StringWriter();
                        msgLog = new MessageLogger(strWriter);
                        settings = new StackSettings();
                }
        }

        public class StackSettings {
                public StackSettings() {
                        LoadFromReg();
                        //throw new NotImplementedException("Stack Settings not implemented");
                }

                private int myDeviceID = -1 ;

                public ushort MyDeviceID {
                        get { if (myDeviceID >= 0) {
                                          return (ushort)myDeviceID; 
                                  } else {
                                          throw new ApplicationException("Unable to fetch Device ID for stack - no device ID set");
                                  }
                        } 
                        set { myDeviceID = value;}
                }

                public int ClientReceivePortNumber {
                        get { return 30481; }
                }
                private int clientRxPortNum; 

                public int ClientSendFromPortNumber {
                        get { return 12346; }
                }

                public int ServerSendFromPortNumber {
                        get { return 12345; }
                }

                public int ServerReceivePortNumber {
                        get { return 30481; }
                }
                private int serverRxPortNum;

                private void LoadFromReg() {
                        // TODO: Implement CE Registry
                        //                      RegistryKey regKey = Registry.CurrentUser.OpenSubKey("Software\\University of Cambridge\\GPRSWeb", true);
                        myDeviceID = 1; //(int)regKey.GetValue("DeviceID", -1); 
                        defaultBDP = 8 * 1024;  //(int)regKey.GetValue("DefaultBDP", -1);
                        interAckableTime = 1; //(int)regKey.GetValue("InterAckableTime", -1);
                        firstAckableTime = 2; //(int)regKey.GetValue("FirstAckableTime", -1);
                        ackArrivalTimeout = 60; // (int)regKey.GetValue("AckArrivalTimeout", -1);
                        serverIP = "131.111.251.169"; //(string)regKey.GetValue("ServerIP", "");
                        clientIP = "128.232.98.28"; //(string)regKey.GetValue("ClientIP", "");
                        clientRxPortNum = 30481; //(int)regKey.GetValue("ClientRxPort", -1);
                        serverRxPortNum = 30481; //(int)regKey.GetValue("ServerRxPort", -1);
                }

                private int defaultBDP;
                public int DefaultBandwidthDelayProdut {
                        get { 
                                if (defaultBDP >= 0) {
                                        return defaultBDP; 
                                } else {
                                        throw new ApplicationException("Unable to fetch Default Bandwidth Deplay Product - not set");
                                }
                        }
                }

                private int interAckableTime;
                public int InterAckableTime {
                        get { 
                                if (interAckableTime >= 0) {
                                        return interAckableTime; 
                                } else {
                                        throw new ApplicationException("Unable to fetch InterAckableTime - not set");
                                }
                        }
                }

                private int firstAckableTime;
                public int FirstAckableTime {
                        get { 
                                if (firstAckableTime >= 0) {
                                        return firstAckableTime; 
                                } else {
                                        throw new ApplicationException("Unable to fetch FirstAckableTime - not set");
                                }
                        }
                }

                private int ackArrivalTimeout;
                public int AckArrivalTimeout {
                        get { 
                                if (ackArrivalTimeout >= 0) {
                                        return ackArrivalTimeout; 
                                } else {
                                        throw new ApplicationException("Unable to fetch AckArrivalTimeout- not set");
                                }
                        }
                }

                private string serverIP;
                public IPAddress ServerIP {
                        get {
                                try {
                                        return IPAddress.Parse(serverIP);
                                } catch (Exception ex) {
                                        throw new ApplicationException("Unable to fetch Server IP\r\n" + ex.ToString());
                                }
                        } 
                        set {
                                serverIP = value.ToString();
                        }
                }

                private string clientIP;
                public IPAddress ClientIP {
                        get {
                                try {
                                        return IPAddress.Parse(clientIP);
                                } catch (Exception ex) {
                                        throw new ApplicationException("Unable to fetch Client IP\r\n" + ex.ToString());
                                }
                        }
                        set { clientIP = value.ToString(); }
                }

                public ushort SERVER_DEVICE_ID {
                        get { return 0; }
                }
        }
}

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