/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
    * with the License.  You may obtain a copy of the License at
    *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  package org.apache.mina.transport.vmpipe;
  
  import static org.junit.Assert.fail;
  
  import java.lang.management.ManagementFactory;
  import java.lang.management.ThreadInfo;
  import java.lang.management.ThreadMXBean;
  import java.util.concurrent.CountDownLatch;
  import java.util.concurrent.TimeUnit;
  import java.util.concurrent.atomic.AtomicReference;
  
  import org.apache.mina.core.future.ConnectFuture;
  import org.apache.mina.core.service.IoAcceptor;
  import org.apache.mina.core.service.IoConnector;
  import org.apache.mina.core.service.IoHandlerAdapter;
  import org.apache.mina.core.session.IoSession;
  import org.junit.Test;
  
  /**
   * TODO Add documentation
   * 
   * @author <a href="http://mina.apache.org">Apache MINA Project</a>
   */
  public class VmPipeSessionCrossCommunicationTest {
      @Test
      public void testOneSessionTalkingBackAndForthDoesNotDeadlock() throws Exception {
          final VmPipeAddress address = new VmPipeAddress(1);
          final IoConnector connector = new VmPipeConnector();
          final AtomicReference<IoSession> c1 = new AtomicReference<IoSession>();
          final CountDownLatch latch = new CountDownLatch(1);
          final CountDownLatch messageCount = new CountDownLatch(2);
          IoAcceptor acceptor = new VmPipeAcceptor();
  
          acceptor.setHandler(new IoHandlerAdapter() {
              @Override
              public void messageReceived(IoSession session, Object message) throws Exception {
                  //System.out.println(Thread.currentThread().getName() + ": " + message);
  
                  if ("start".equals(message)) {
                      session.write("open new");
                  } else if ("re-use c1".equals(message)) {
                      session.write("tell me something on c1 now");
                  } else if (((String) message).startsWith("please don't deadlock")) {
                      messageCount.countDown();
                  } else {
                      fail("unexpected message received " + message);
                  }
              }
          });
          acceptor.bind(address);
  
          connector.setHandler(new IoHandlerAdapter() {
              @Override
              public void messageReceived(IoSession session, Object message) throws Exception {
                  //System.out.println(Thread.currentThread().getName() + ": " + message);
  
                  if ("open new".equals(message)) {
                      //System.out.println("opening c2 from " + Thread.currentThread().getName());
  
                      IoConnector c2 = new VmPipeConnector();
                      c2.setHandler(new IoHandlerAdapter() {
                          @Override
                          public void sessionOpened(IoSession session) throws Exception {
                              session.write("re-use c1");
                          }
  
                          @Override
                          public void messageReceived(IoSession session, Object message) throws Exception {
                              //System.out.println(Thread.currentThread().getName() + ": " + message);
  
                              if ("tell me something on c1 now".equals(message)) {
                                  latch.countDown();
                                  c1.get().write("please don't deadlock via c1");
                              } else {
                                  fail("unexpected message received " + message);
                              }
                          }
                      });
  
                      ConnectFuture c2Future = c2.connect(address);
  
                     c2Future.await();
 
                     latch.await();
 
                     c2Future.getSession().write("please don't deadlock via c2");
                 } else {
                     fail("unexpeced message received " + message);
                 }
             }
         });
 
         ConnectFuture future = connector.connect(address);
 
         future.await();
 
         c1.set(future.getSession());
         c1.get().write("start");
 
         ThreadMXBean threadMXBean = ManagementFactory.getThreadMXBean();
 
         while (!messageCount.await(100, TimeUnit.MILLISECONDS)) {
             long[] threads = threadMXBean.findMonitorDeadlockedThreads();
 
             if (null != threads) {
                 StringBuffer sb = new StringBuffer(256);
                 ThreadInfo[] infos = threadMXBean.getThreadInfo(threads, Integer.MAX_VALUE);
 
                 for (ThreadInfo info : infos) {
                     sb.append(info.getThreadName())
                             .append(" blocked on ")
                             .append(info.getLockName())
                             .append(" owned by ")
                             .append(info.getLockOwnerName())
                             .append("\n");
                 }
 
                 for (ThreadInfo info : infos) {
                     sb.append("\nStack for ").append(info.getThreadName()).append("\n");
                     for (StackTraceElement element : info.getStackTrace()) {
                         sb.append("\t").append(element).append("\n");
                     }
                 }
 
                 fail("deadlocked! \n" + sb);
             }
         }
 
         acceptor.setCloseOnDeactivation(false);
         acceptor.dispose();
     }
 }