//
   //  ========================================================================
   //  Copyright (c) 1995-2016 Mort Bay Consulting Pty. Ltd.
   //  ------------------------------------------------------------------------
   //  All rights reserved. This program and the accompanying materials
   //  are made available under the terms of the Eclipse Public License v1.0
   //  and Apache License v2.0 which accompanies this distribution.
   //
   //      The Eclipse Public License is available at
  //      http://www.eclipse.org/legal/epl-v10.html
  //
  //      The Apache License v2.0 is available at
  //      http://www.opensource.org/licenses/apache2.0.php
  //
  //  You may elect to redistribute this code under either of these licenses.
  //  ========================================================================
  //
  
  package org.eclipse.jetty.client;
  
  import java.util.concurrent.TimeUnit;
  import java.util.concurrent.TimeoutException;
  import java.util.concurrent.atomic.AtomicReference;
  
  import org.eclipse.jetty.client.api.Request;
  import org.eclipse.jetty.client.api.Response;
  import org.eclipse.jetty.client.api.Result;
  import org.eclipse.jetty.util.log.Log;
  import org.eclipse.jetty.util.log.Logger;
  import org.eclipse.jetty.util.thread.Scheduler;
  
  public class TimeoutCompleteListener implements Response.CompleteListener, Runnable
  {
      private static final Logger LOG = Log.getLogger(TimeoutCompleteListener.class);
  
      private final AtomicReference<Scheduler.Task> task = new AtomicReference<>();
      private final Request request;
  
      public TimeoutCompleteListener(Request request)
      {
          this.request = request;
      }
  
      @Override
      public void onComplete(Result result)
      {
          cancel();
      }
  
      public boolean schedule(Scheduler scheduler)
      {
          long timeout = request.getTimeout();
          Scheduler.Task task = scheduler.schedule(this, timeout, TimeUnit.MILLISECONDS);
          Scheduler.Task existing = this.task.getAndSet(task);
          if (existing != null)
          {
              existing.cancel();
              cancel();
              throw new IllegalStateException();
          }
          if (LOG.isDebugEnabled())
              LOG.debug("Scheduled timeout task {} in {} ms for {}", task, timeout, request);
          return true;
      }
  
      @Override
      public void run()
      {
          if (LOG.isDebugEnabled())
              LOG.debug("Executing timeout task {} for {}", task, request);
          request.abort(new TimeoutException("Total timeout elapsed"));
      }
  
      public void cancel()
      {
          Scheduler.Task task = this.task.getAndSet(null);
          if (task != null)
          {
              boolean cancelled = task.cancel();
              if (LOG.isDebugEnabled())
                  LOG.debug("Cancelled (successfully: {}) timeout task {}", cancelled, task);
          }
      }
  }