/*************************************************************************

"FreePastry" Peer-to-Peer Application Development Substrate 

Copyright 2002, Rice University. All rights reserved.

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- Redistributions of source code must retain the above copyright
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- Redistributions in binary form must reproduce the above copyright
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- Neither  the name  of Rice  University (RICE) nor  the names  of its
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This software is provided by RICE and the contributors on an "as is"
basis, without any representations or warranties of any kind, express
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********************************************************************************/
/*
 *  Created on Apr 15, 2005
 */
package rice.tutorial.lesson5;

import rice.environment.Environment;
import rice.p2p.commonapi.Application;
import rice.p2p.commonapi.CancellableTask;
import rice.p2p.commonapi.Endpoint;
import rice.p2p.commonapi.Id;
import rice.p2p.commonapi.Message;
import rice.p2p.commonapi.Node;
import rice.p2p.commonapi.NodeHandle;
import rice.p2p.commonapi.RouteMessage;
import rice.tutorial.lesson3.MyMsg;

/**
 * This app shows how to trigger regularly scheduled events on the FreePastry
 * thread.
 *
 * @version $Id: pretty.settings 2305 2005-03-11 20:22:33Z jeffh $
 * @author Jeff Hoye
 */
public class MyApp implements Application {

  /**
   * This is the task sends the MessageToSelf every 5 seconds. We keep it as a
   * member variable to cancel later.
   */
  CancellableTask messageToSelfTask;

  /**
   * The Endpoint represents the underlieing node. By making calls on the
   * Endpoint, it assures that the message will be delivered to a MyApp on
   * whichever node the message is intended for.
   */
  protected Endpoint endpoint;

  /**
   * DESCRIBE THE FIELD
   */
  protected Environment environment;

  /**
   * Constructor for MyApp.
   *
   * @param node DESCRIBE THE PARAMETER
   */
  public MyApp(Node node) {
    this.environment = node.getEnvironment();
    // We are only going to use one instance of this application on each PastryNode
    this.endpoint = node.registerApplication(this, "myinstance");
    // Send MessageToSelf every 5 seconds, starting in 3 seconds
    messageToSelfTask = endpoint.scheduleMessage(new MessageToSelf(), 3000, 5000);
  }

  /**
   * Call this to cancel the task.
   */
  public void cancelTask() {
    messageToSelfTask.cancel();
  }


  /**
   * Called to route a message to the id
   *
   * @param id DESCRIBE THE PARAMETER
   */
  public void routeMyMsg(Id id) {
    System.out.println(this + " sending to " + id);
    Message msg = new MyMsg(endpoint.getId(), id);
    endpoint.route(id, msg, null);
  }

  /**
   * Called to directly send a message to the nh
   *
   * @param nh DESCRIBE THE PARAMETER
   */
  public void routeMyMsgDirect(NodeHandle nh) {
    System.out.println(this + " sending direct to " + nh);
    Message msg = new MyMsg(endpoint.getId(), nh.getId());
    endpoint.route(null, msg, nh);
  }

  /**
   * Called when we receive a message.
   *
   * @param id DESCRIBE THE PARAMETER
   * @param message DESCRIBE THE PARAMETER
   */
  public void deliver(Id id, Message message) {
    System.out.println(this + " received " + message);
    if (message instanceof MessageToSelf) {
      // This will get called every 5 seconds, on Pastry's thread.
      // Thus now we can assume we are on Pastry's thread.
      // TODO: whatever... send messages to other nodes? print out status?
      System.out.println("I got the MessageToSelf at time:" + environment.getTimeSource().currentTimeMillis());
    }
  }

  /**
   * Called when you hear about a new neighbor. Don't worry about this method
   * for now.
   *
   * @param handle DESCRIBE THE PARAMETER
   * @param joined DESCRIBE THE PARAMETER
   */
  public void update(NodeHandle handle, boolean joined) {
  }

  /**
   * Called a message travels along your path. Don't worry about this method for
   * now.
   *
   * @param message DESCRIBE THE PARAMETER
   * @return DESCRIBE THE RETURN VALUE
   */
  public boolean forward(RouteMessage message) {
    return true;
  }

  /**
   * DESCRIBE THE METHOD
   *
   * @return DESCRIBE THE RETURN VALUE
   */
  public String toString() {
    return "MyApp " + endpoint.getId();
  }

  /**
   * NOTE: It is unsafe to send this message to anyone but the localnode. The
   * reason: This is an inner class of MyApp, and therefore has an automatic
   * reference to MyApp which is not serializable! Do not attempt to send over
   * the wire, you will get a NotSerializableException!
   *
   * @version $Id: pretty.settings 2305 2005-03-11 20:22:33Z jeffh $
   * @author jeffh
   */
  class MessageToSelf implements Message {
    /**
     * Gets the Priority attribute of the MessageToSelf object
     *
     * @return The Priority value
     */
    public int getPriority() {
      return 0;
    }
  }

}
