MainWindow.xaml.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.Windows.Threading;

namespace csma_cd
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        //text_array represents textblock.. in this project we have created 3 textblock object as a packets
        // and we named it packet1 ,packet 2 and packet 3
        TextBlock[] text_array = new TextBlock[3];

        //if any packet got collide
        bool packet1_got_collided = false;
        bool packet2_got_collided = false;
        bool packet3_got_collided = false;

        //if packet reached at router
        bool is_packet1_reached = false;
        bool is_packet2_reached = false;
        bool is_packet3_reached = false;
        bool all_packets_reached = false;


        //initial value coordinate of all 3 packets.. 
        //once packet get collide packet will be resending  from their inital position after some random amount of time
        double packet1_left;
        double packet2_top;
        double packet2_left;

        double packet3_top;
        double packet3_left;
        Random rand = new Random();
        DateTime p1_backofftime;
        DateTime p2_backofftime;
        DateTime p3_backofftime;
        bool is_start_btn_clicked = false;
        List<TextBlock> collided_packet_list = new List<TextBlock>(3);
        DispatcherTimer timer = new DispatcherTimer();

        double speed_of_p1 = 1.5;
        double speed_of_p2 = 0.5;
        double speed_of_p3 = 1.0;
        static int max_try = 3;
        int max_try_of_p1 = max_try;

        int max_try_of_p2 = max_try;
        int max_try_of_p3 = max_try;
        List<TextBlock> packet_on_the_way = new List<TextBlock>(3);
        bool if_medium_is_idle = true;
        public void move(TextBlock[] text_array, double speed_of_p1, double speed_of_p2, double speed_of_p3)
        {
            foreach (TextBlock r in packet_on_the_way)
            {
                if (r.Equals(text1))
                {
                  

                   
                        //move
                        if (!packet1_got_collided)
                        {
                            if (collided_packet_list.Contains(text1))
                                collided_packet_list.Remove(text1);
                            if ((Canvas.GetLeft(center_text)) - (Canvas.GetLeft(text1)) < 10 && !is_packet1_reached)
                                if_medium_is_idle = false;
                            if (Canvas.GetLeft(text1) < Canvas.GetLeft(router_img) && !is_packet1_reached)
                                Canvas.SetLeft(text1, Canvas.GetLeft(text1) + speed_of_p1);
                            else if (!is_packet1_reached)
                            {
                                // MessageBox.Show("packet 1 reached at router");
                                log.Items.Add("packet 1 reached at router");
                                if_medium_is_idle = true;

                                is_packet1_reached = true;
                                Canvas.SetLeft(text1, packet1_left);

                            }

                        

                    }
                }// if r equals to text1

                else if (r.Equals(text2))
                {
                   
                        if (!packet2_got_collided )
                        {
                            if (collided_packet_list.Contains(text2))
                                collided_packet_list.Remove(text2);

                            if ((Canvas.GetTop(center_text)) - (Canvas.GetTop(text2)) < 10 && !is_packet2_reached)
                                if_medium_is_idle = false;

                            if (Canvas.GetTop(text2) < Canvas.GetTop(center_text) && !is_packet2_reached)
                            {
                                // packet reached at the middle
                                Canvas.SetTop(text2, Canvas.GetTop(text2) + speed_of_p2);
                            }
                            else if (!is_packet2_reached)
                            {

                                Canvas.SetLeft(text2, Canvas.GetLeft(text2) + speed_of_p2);
                                if (Canvas.GetLeft(text2) > Canvas.GetLeft(router_img))
                                {
                                    is_packet2_reached = true;
                                    //MessageBox.Show("packet 2 reached at router ");
                                    log.Items.Add("packet 2 reached at router");
                                    Canvas.SetLeft(text2, packet2_left);
                                    Canvas.SetTop(text2, packet2_top);
                                    if_medium_is_idle = true;



                                


                            }
                        }

                    }

                }//text2


                else if (r.Equals(text3))
                {
                   
                    if (!packet3_got_collided )
                    {
                        if (collided_packet_list.Contains(text3))
                            collided_packet_list.Remove(text3);
                            if ((Canvas.GetTop(text3)) - (Canvas.GetTop(center_text)) < 10 && !is_packet3_reached)
                                if_medium_is_idle = false;

                            if (Canvas.GetTop(text3) > Canvas.GetTop(center_text) && !is_packet3_reached)
                        {
                            // packet reached at the middle
                            Canvas.SetTop(text3, Canvas.GetTop(text3) - speed_of_p3);
                        }
                        else if (!is_packet3_reached)
                        {

                            Canvas.SetLeft(text3, Canvas.GetLeft(text3) + speed_of_p3);
                            if (Canvas.GetLeft(text3) > Canvas.GetLeft(router_img))
                            {
                                is_packet3_reached = true;
                                // MessageBox.Show("packet 3 reached at router ");
                                log.Items.Add("packet 3 reached at router");
                                Canvas.SetLeft(text3, packet3_left);
                                Canvas.SetTop(text3, packet3_top);

                                    if_medium_is_idle = true;


                                }


                            
                    }

                }

                }//text3




            }//for each


            if (is_packet1_reached && packet_on_the_way.Contains(text1))
            {
                packet_on_the_way.Remove(text1);
            }

            if (is_packet1_reached && packet_on_the_way.Contains(text1))
            {
                packet_on_the_way.Remove(text1);
            }
            if (is_packet1_reached && packet_on_the_way.Contains(text1))
            {
                packet_on_the_way.Remove(text1);
            }

            double p1_left_cd = Canvas.GetLeft(text1);
            double p2_left_cd = Canvas.GetLeft(text2);
            double p3_left_cd = Canvas.GetLeft(text3);

            double p1_top_cd = Canvas.GetTop(text1);
            double p2_top_cd = Canvas.GetTop(text2);
            double p3_top_cd = Canvas.GetTop(text3);
            //if p1 and p2 collides
            if (Math.Abs(p1_left_cd - p2_left_cd) < 40 && Math.Abs(p1_top_cd - p2_top_cd) < 20 && !packet1_got_collided && !packet2_got_collided)
            {
        
                packet1_got_collided = true;
                packet2_got_collided = true;
                collided_packet_list.Add(text1);
                collided_packet_list.Add(text2);
              
                packet_on_the_way.Remove(text1);
                packet_on_the_way.Remove(text2);

                log.Items.Add("packet 1 and packet 2 got colide.... ");
                if_medium_is_idle = true;
                int r1 = rand.Next(1, 5);
                int r2 = rand.Next(5, 10);
                p1_backofftime = DateTime.Now.AddSeconds(r1);
                p2_backofftime = DateTime.Now.AddSeconds(r2);
                Canvas.SetLeft(text1, packet1_left);
                Canvas.SetTop(text2, packet2_top);
                Canvas.SetLeft(text2, packet2_left);

            }


            //if p1 and p3 collides
            if (Math.Abs(p1_left_cd - p3_left_cd) < 40 && Math.Abs(p1_top_cd - p3_top_cd) < 20 && !packet1_got_collided && !packet3_got_collided)
            {
                // MessageBox.Show("collided" + packet1_left + " " + p2_top_cd);

                packet3_got_collided = true;

                packet1_got_collided = true;
                collided_packet_list.Add(text1);
                collided_packet_list.Add(text3);

                packet_on_the_way.Remove(text1);
                packet_on_the_way.Remove(text3);
                log.Items.Add("packet 1 and packet 3 got colide.... ");
                if_medium_is_idle = true;
                int r1 = rand.Next(1, 5);
                int r2 = rand.Next(5, 10);
                p1_backofftime = DateTime.Now.AddSeconds(r1);
                p3_backofftime = DateTime.Now.AddSeconds(r2);
                Canvas.SetLeft(text1, packet1_left);
                Canvas.SetTop(text3, packet3_top);
                Canvas.SetLeft(text3, packet3_left);

            }

            //if p2 and p3 collides
            if (Math.Abs(p2_left_cd - p3_left_cd) < 40 && Math.Abs(p2_top_cd - p3_top_cd) < 20 && !packet2_got_collided && !packet3_got_collided)
            {
                // MessageBox.Show("collided" + packet1_left + " " + p2_top_cd);

                packet2_got_collided = true;
                packet3_got_collided = true;

                collided_packet_list.Add(text2);
                collided_packet_list.Add(text3);

                packet_on_the_way.Remove(text2);
                packet_on_the_way.Remove(text3);
                int r1 = rand.Next(1, 5);
                int r2 = rand.Next(5, 10);
                p2_backofftime = DateTime.Now.AddSeconds(r1);
                p3_backofftime = DateTime.Now.AddSeconds(r2);
                log.Items.Add("packet 2 and packet 3 got colide.... ");
                if_medium_is_idle = true;


                Canvas.SetTop(text2, packet2_top);
                Canvas.SetLeft(text2, packet2_left);
                Canvas.SetTop(text3, packet3_top);
                Canvas.SetLeft(text3, packet3_left);

            }


            if (collided_packet_list.Count > 0)
            {
                foreach (TextBlock tc in collided_packet_list)
                {

                    if (if_medium_is_idle)
                    {   
                        if(tc.Equals(text1))
                        {
                            if (p1_backofftime < DateTime.Now)
                            {
                                packet1_got_collided = false;
                                // collided_packet_list.Remove(text1);
                                packet_on_the_way.Add(text1);
                                log.Items.Add("medium is idle.. resending the packet 1");
                                packet1_got_collided = false;
                            }
                          
                        }
                        else if (tc.Equals(text2))
                        {
                            if (p2_backofftime < DateTime.Now)
                            {
                                packet2_got_collided = false;
                                // collided_packet_list.Remove(text1);
                                packet_on_the_way.Add(text2);
                                log.Items.Add("medium is idle.. resending the packet 2");
                            }
                        }
                        else if (tc.Equals(text3))
                        {
                            if (p3_backofftime < DateTime.Now)
                            {
                                packet3_got_collided = false;
                                // collided_packet_list.Remove(text1);
                                packet_on_the_way.Add(text3);
                                log.Items.Add("medium is idle.. resending the packet 3");
                            }
                        }


                    }

                }

                

            }

            if (is_packet1_reached && is_packet2_reached && is_packet3_reached)
            {
                MessageBox.Show("all packets are reached");
                log.Items.Add("All packet are received by router");
                reset_all_gui(0);
            }


        }

        public MainWindow()
        {
            InitializeComponent();
            text_array[0] = text1;
            text_array[1] = text2;
            text_array[2] = text3;
            packet1_left = Canvas.GetLeft(text1);
            packet2_top = Canvas.GetTop(text2);
            packet2_left = Canvas.GetLeft(text2);
            packet3_top = Canvas.GetTop(text3);
            packet3_left = Canvas.GetLeft(text3);

            timer.Tick += new EventHandler(init);
            timer.Interval = new TimeSpan(0, 0, 0, 0, 20);
            //  MessageBox.Show(Canvas.GetTop(text3).ToString());

        }

        public void init(object sender, EventArgs e)
        {

            p1_speed_text_block.IsEnabled = false;
            p2_speed_text_block.IsEnabled = false;
            p3_speed_text_block.IsEnabled = false;

            move(text_array, speed_of_p1, speed_of_p2, speed_of_p3);

        }

        private void stop_btn_Click(object sender, RoutedEventArgs e)
        {
            is_start_btn_clicked = false;
            timer.Stop();
        }

        private void start_btn_Click(object sender, RoutedEventArgs e)
        {
            is_start_btn_clicked = true;
            log.Items.Add("click on the computer icon to send message to router ");

            if (p1_speed_text_block.Text.Length > 0)
            {
                try
                {
                    speed_of_p1 = Convert.ToDouble(p1_speed_text_block.Text);
                }
                catch
                {
                    MessageBox.Show("input should be decimal and less than 10");
                }
            }

            if (p2_speed_text_block.Text.Length > 0)
            {
                try
                {
                    speed_of_p2 = Convert.ToDouble(p2_speed_text_block.Text);
                }
                catch
                {
                    MessageBox.Show("input should be decimal and less than 10");

                }
            }


            if (p3_speed_text_block.Text.Length > 0)
            {
                try
                {
                    speed_of_p3 = Convert.ToDouble(p3_speed_text_block.Text);
                }
                catch
                {
                    MessageBox.Show("input should be decimal and less than 10");

                }
            }


            if (max_try_box.Text.Length > 0)
            {
                try
                {
                    max_try = Convert.ToInt32(p3_speed_text_block.Text);
                }
                catch
                {
                    MessageBox.Show("maxt attempt should be integer");

                }
            }



            timer.Start();
        }


        private void reset_all_gui(int reset_btn_clicked = 1)
        {
            timer.Stop();

            packet1_got_collided = false;
            packet2_got_collided = false;
            packet3_got_collided = false;

            is_packet1_reached = false;
            is_packet2_reached = false;
            is_packet3_reached = false;
            all_packets_reached = false;

            max_try_of_p1 = max_try;
            max_try_of_p2 = max_try;
            max_try_of_p3 = max_try;


            packet_on_the_way.Clear();
            if_medium_is_idle = true;

            collided_packet_list.Clear();

            speed_of_p1 = 1.5;
            speed_of_p2 = 0.5;
            speed_of_p3 = 1.0;
            if (reset_btn_clicked == 1)
                log.Items.Clear();

            Canvas.SetLeft(text1, packet1_left);
            Canvas.SetLeft(text2, packet2_left);
            Canvas.SetTop(text2, packet2_top);

            Canvas.SetLeft(text3, packet3_left);
            Canvas.SetTop(text3, packet3_top);
            p1_speed_text_block.IsEnabled = true;
            p2_speed_text_block.IsEnabled = true;
            p3_speed_text_block.IsEnabled = true;

        }

        private void reset_btn_Click(object sender, RoutedEventArgs e)
        {
            is_start_btn_clicked = false;
            reset_all_gui();

        }



        private void c1_left_btn_up(object sender, MouseButtonEventArgs e)
        {
            if(!is_start_btn_clicked)
            {
                MessageBox.Show("first start the simulation");
                return;
            }
            if(!packet_on_the_way.Contains(text1) )
            {
                if (if_medium_is_idle)
                {
                    packet_on_the_way.Add(text1);
                    log.Items.Add("medium is idle.. packet is ready to go");
                }

                else
                    log.Items.Add("medium is busy.. wait");


            }

            else { MessageBox.Show("already in transit"); }
        }


        private void c2_left_btn_up(object sender, MouseButtonEventArgs e)
        {
            if (!is_start_btn_clicked)
            {
                MessageBox.Show("first start the simulation");
                return;
            }

            if (!packet_on_the_way.Contains(text2))
            {
                if (if_medium_is_idle)
                {
                    packet_on_the_way.Add(text2);
                    log.Items.Add("medium is idle.. packet is ready to go");
                }

                else
                    log.Items.Add("medium is busy.. wait");


            }
            else { MessageBox.Show("already in transit"); }


        }



        private void c3_left_btn_up(object sender, MouseButtonEventArgs e)
        {
            if (!is_start_btn_clicked)
            {
                MessageBox.Show("first start the simulation");
                return;
            }

            if (!packet_on_the_way.Contains(text3))
            {
                if (if_medium_is_idle)
                {
                    packet_on_the_way.Add(text3);
                    log.Items.Add("medium is idle.. packet is ready to go");
                }

                else
                    log.Items.Add("medium is busy.. wait");


            }

            else { MessageBox.Show("already in transit"); }


        }
    }
}