package org.sim0mq.demo.reqrep;
   
   import org.djutils.serialization.SerializationException;
   import org.sim0mq.Sim0MQException;
   import org.sim0mq.message.Sim0MQMessage;
   import org.zeromq.SocketType;
   import org.zeromq.ZContext;
   import org.zeromq.ZMQ;
   
  /**
   * <p>
   * Copyright (c) 2013-2020 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
   * BSD-style license. See <a href="http://sim0mq.org/docs/current/license.html">Sim0MQ License</a>.
   * </p>
   * $LastChangedDate: 2015-07-24 02:58:59 +0200 (Fri, 24 Jul 2015) $, @version $Revision: 1147 $, by $Author: averbraeck $,
   * initial version Aug 4, 2018 <br>
   * @author <a href="http://www.tbm.tudelft.nl/averbraeck">Alexander Verbraeck</a>
   */
  public class Rep
  {
      /**
       * @param args command line arguments
       * @throws Sim0MQException on error
       */
      protected Rep(final String[] args) throws Sim0MQException
      {
          if (args.length < 2)
          {
              System.err.println("Use as Rep startport #threads [#contexts]");
              System.exit(-1);
          }
  
          int startport = Integer.parseInt(args[0]);
          long numthreads = Integer.parseInt(args[1]);
          int numcontexts = args.length > 2 ? Integer.parseInt(args[2]) : 1;
  
          ZContext context = new ZContext(numcontexts);
  
          for (int i = 0; i < numthreads; i++)
          {
              new RepThread(context, startport + i).start();
          }
  
          context.destroy();
      }
  
      /**
       * @param args command line arguments
       * @throws Sim0MQException on error
       */
      public static void main(final String[] args) throws Sim0MQException
      {
          new Rep(args);
      }
  
      /** The worker thread for the REP requests. */
      protected class RepThread extends Thread
      {
          /** the (shared) context. */
          private final ZContext context;
  
          /** the port to use. */
          private final int port;
  
          /**
           * @param context the (shared) context
           * @param port the port to use
           */
          public RepThread(final ZContext context, final int port)
          {
              this.context = context;
              this.port = port;
          }
  
          /** {@inheritDoc} */
          @Override
          public void run()
          {
              // Socket to talk to server
              System.out.println("REP: Connecting to server with thread on port " + this.port);
  
              // Socket to talk to clients
              ZMQ.Socket socket = this.context.createSocket(SocketType.REP);
              socket.bind("tcp://*:" + this.port);
  
              String senderId = "REP." + this.port;
              String receiverId = "REQ." + this.port;
  
              int messagenr = 0;
  
              while (true)
              {
                  try
                  {
                      // Wait for next request from the client
                      byte[] request = socket.recv(0);
                      Object[] message = Sim0MQMessage.decode(request).createObjectArray();
  
                      if (message[4].toString().equals("STOP"))
                     {
                         // send a reply
                         Object[] reply = new Object[] { "STOPPED" };
                         socket.send(Sim0MQMessage.encodeUTF8(true, message[1], senderId, receiverId, "STOPPED", messagenr,
                                 reply), 0);
                         break;
                     }
 
                     // check the message
                     if (!message[3].toString().equals(senderId))
                     {
                         System.err.println(Sim0MQMessage.print(message));
                         System.err.println("receive message " + messagenr + " for port " + this.port + ", receiver = "
                                 + message[3].toString() + ", expected " + senderId);
                     }
                     if (((Number) message[7]).intValue() == 0)
                     {
                         System.err.println(Sim0MQMessage.print(message));
                         System.err.println("receive message " + messagenr + " for port " + this.port + ", #fields = 0");
                     }
                     else if (((Number) message[5]).intValue() != messagenr)
                     {
                         System.err.println(Sim0MQMessage.print(message));
                         System.err.println(
                                 "receive message " + messagenr + " for port " + this.port + ", payload# = " + message[5]);
                     }
 
                     // send a reply
                     Object[] reply = new Object[] { message[8], message[9] };
                     socket.send(Sim0MQMessage.encodeUTF8(true, message[1], senderId, receiverId, "REPLY", messagenr,
                             reply), 0);
                 }
                 catch (Sim0MQException | SerializationException exception)
                 {
                     exception.printStackTrace();
                 }
                 
                 // increase the messagenr
                 messagenr++;
             }
 
             socket.close();
 
         }
 
     }
 
 }