package mil.navy.nps.testing;

import java.net.*;
import java.util.*;
/**

  DatagramReader:  Datagram socket reader

  Some test programming to figure out what's going on with 
  datagram sockets. This just listens on a port for datagrams,
  accepting them and throwing them away.
  
*/

import java.io.*;
import mil.navy.nps.dis.*;

public class DatagramReader 

{
    public static void main(String args[]) throws IOException

    {

        DatagramPacket  aPacket;                        // One packet read from the socket
        DatagramSocket  theSocket;                      // Socket we read from

        byte            packetBuff[] = new byte[1500];  // Buffer for datagram packet
        String          infoString;

        int             packetReceivedCount = 0;
        int             idx = 0;

        long            time1, time2, timeDifference;
        String          sockNo = new String("8004");
        boolean         firstPacket = false;


        EntityStatePdu  aPdu;


  time1 = 0;

  for(idx = 0; idx < args.length; idx++)
   {

    if((args[idx].equals("-h")) || (args[idx].equals("-?") ) )
    {
      System.out.println("Command line options: ");
      System.out.println("  -sockNo <sock no>                  Socket to listen to on this machine");

       return;
    }

   if(args[idx].equals("-sockNo"))
       {
         sockNo = args[idx+1];
         System.out.println("got command line arg of -sockNo with value of " + sockNo);
       }   

   }
        
  System.out.println("starting up reader process...");

  theSocket = new DatagramSocket(Integer.valueOf(sockNo).intValue());
  aPacket   = new DatagramPacket(packetBuff, 1500);

  while(true)
    {
       theSocket.receive(aPacket); 

       if(firstPacket == false)
         time1 = System.currentTimeMillis();

       firstPacket = true;


       //aPdu = (EntityStatePdu)ProtocolDataUnit.datagramToPdu(aPacket);
       packetReceivedCount++;

       if((packetReceivedCount) % 100 == 0)
        {
           System.out.println("Got " + packetReceivedCount + " packets");
            
            if(packetReceivedCount >= 5000)
              {
                time2 = System.currentTimeMillis();
                timeDifference = time2 - time1;
                System.out.println("Time required to receive" + packetReceivedCount + " packets = " + timeDifference);
                System.out.println("packet length of " + aPacket.getLength());
                //aPdu.printValues(5);

                break;
               }
        } // end of if mod 100


      }    // end of while

    }      // end of main

}          // end of class