//-----------------------------------------------------------------
// CSE 461 Project 1:                   Provided client code
//
// This file implements the main driver loop for the program.
// It creates a sender and a receiver, connects them, and then
// sends a stream of data and measures the performance.  You
// shouldn't need to change anything but parameters in this file.
//
// See sender.java and receiver.java for the implementations
// of the sender and receiver algorithms
//
// USAGE:  java project1 [seed]
//-----------------------------------------------------------------
import java.io.*;
import java.util.*;

public class project1 implements Runnable
{
   // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
   // main entry point.  Create an actual instance and call that.
   // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
   public static void main (String[] args)
   {
      project1 runProject = new project1 ();
      ParseArgs (args);
      runProject.Go (args);
   }

   public static long SEED = System.currentTimeMillis ();

   public static int LINK_MTU = 20;

   public static double LINK_BW = 1.0;
   public static double LINK_BW_SD = 0.2;
   public static double LINK_BW_WALK = 0.5;

   public static double LINK_LATENCY = 2.0;
   public static double LINK_LATENCY_SD = 0.5;
   public static double LINK_LATENCY_WALK = 0.5;

   public static double LINK_DROP_PROB = 0.25;

   private static void ParseArgs (String[] args)
   {
      for (int i=0; i<args.length; ++i)
         {
         int eqidx = args[i].indexOf ('=');
         if (eqidx == -1)
            continue;

         String prefix = args[i].substring (0, eqidx);
         String value = args[i].substring (eqidx + 1);

         if (prefix.equals ("seed"))
            SEED = ParseLong (value, 0);

         else if (prefix.equals ("bandwidth"))
            {
            LINK_BW = ParseDouble (value, 1.0);
            LINK_BW_SD = LINK_BW / 5.0;
            }
         else if (prefix.equals ("bandwidth-walk"))
            LINK_BW_WALK = ParseDouble (value, 1.0);

         else if (prefix.equals ("latency"))
            {
            LINK_LATENCY = ParseDouble (value, 1.0);
            LINK_LATENCY_SD = LINK_LATENCY / 4.0;
            }
         else if (prefix.equals ("latency-walk"))
            LINK_LATENCY_WALK = ParseDouble (value, 1.0);

         else if (prefix.equals ("drop-prob"))
            LINK_DROP_PROB = ParseDouble (value, 0.25);

         else if (prefix.equals ("debug"))
            Debug.SetEnabled (value);
         }

      for (int i=0; i<args.length; ++i)
         {
         if (args[i].equals ("-no-bandwidth-variation"))
            LINK_BW_SD = 0.0;
         if (args[i].equals ("-no-latency-variation"))
            LINK_LATENCY_SD = 0.0;
         }
   }

   private static long ParseLong (String s, long def)
   {
      try
         {
         def = Long.parseLong (s);
         }
      catch (NumberFormatException e)
         {
         }

      return def;
   }

   private static double ParseDouble (String s, double def)
   {
      try 
         {
         def = Double.valueOf (s).doubleValue ();
         }
      catch (NumberFormatException e)
         {
         }
      catch (NullPointerException e)
         {
         }

      return def;
   }

   // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
   // The main run thread: set up everything, and then run the
   // sender, which blasts a stream of data across the link
   // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
   private InternetLinkMonitor monitor;

   private void Go (String[] args)
   {
      timer = new Timer ();
      monitor = new InternetLinkMonitor (timer);
      Link link = new InternetLink (timer, LINK_MTU,
                             LINK_BW, LINK_BW_SD, LINK_BW_WALK,
                             LINK_LATENCY, LINK_LATENCY_SD, LINK_LATENCY_WALK,
                             LINK_DROP_PROB, SEED, monitor);
      Address senderAddr = new Address ("sender");
      Address receiverAddr = new Address ("receiver");

      Project1Sender sender = new Project1Sender (timer, link, senderAddr);
      receiver = new Project1Receiver (timer, link, receiverAddr);

      sender.SetDestination (receiverAddr);

      Thread rcvThread = new Thread (this);
      rcvThread.start ();

      Thread.currentThread ().setName ("Project 1 data sender");

      byte[] data = new byte[50];
      String s = "";
      int count = 0;
      for (;;)
         {
         while (s.length () < 50)
            {
            s = s + " " + count;
            ++count;
            }

         s.getBytes (0, 50, data, 0);
         s = s.substring (50);

         try
            {
            sender.Send (data);
            }
         catch (NoDestinationSet nds)
            {
            System.out.println ("BAD");
            System.exit (1);
            }
         }
   }

   private Timer timer;
   private Project1Receiver receiver;

   // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
   // recevier thread: receive and print data, and compute the
   // observed bandwidth of the link as the time to receive
   // bytes.
   // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
   public void run ()
   {
      Thread.currentThread ().setName ("Project 1 data recevier");
      long oldTime = timer.CurrentSimTime ();
      int linesReceived = 0;
      for (;;)
         {
         byte[] data = receiver.Receive (40);
         long newTime = timer.CurrentSimTime ();

         ++linesReceived;

         String s = new String (data, 0);
         System.out.println ("RECEIVED: '" + s + "' ("
                 + (float)((8.0 * 40.0 * linesReceived)
                           / (newTime - oldTime)) + " Mb/sec)");

         if (linesReceived > 50)
            {
            monitor.PrintStats ();
            System.exit (0);
            }
         }
   }
}