/**
 * 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.activemq.usecases;

import javax.jms.Connection;
import javax.jms.DeliveryMode;
import javax.jms.MessageConsumer;
import javax.jms.MessageProducer;
import javax.jms.Queue;
import javax.jms.Session;
import javax.jms.TextMessage;

import org.apache.activemq.broker.BrokerService;
import org.apache.activemq.broker.region.policy.PolicyEntry;
import org.apache.activemq.broker.region.policy.PolicyMap;

/**
 * Test case intended to demonstrate delivery interruption to queue consumers when a JMS selector leaves some messages
 * on the queue (due to use of a JMS Selector)
 *
 * testNonDiscriminatingConsumer() demonstrates proper functionality for consumers that don't use a selector to qualify
 * their input.
 *
 * testDiscriminatingConsumer() demonstrates the failure condition in which delivery to the consumer eventually halts.
 *
 * The expected behavior is for the delivery to the client to be maintained regardless of the depth of the queue,
 * particularly when the messages in the queue do not meet the selector criteria of the client.
 *
 * https://issues.apache.org/activemq/browse/AMQ-2217
 */
public class DiscriminatingConsumerLoadTest extends TestSupport {

   private static final org.apache.commons.logging.Log LOG = org.apache.commons.logging.LogFactory.getLog(DiscriminatingConsumerLoadTest.class);

   private Connection producerConnection;
   private Connection consumerConnection;

   public static final String JMSTYPE_EATME = "DiscriminatingLoadClient.EatMe";
   public static final String JMSTYPE_IGNOREME = "DiscriminatingLoadClient.IgnoreMe";

   private final int testSize = 5000; // setting this to a small number will pass all tests

   BrokerService broker;

   @Override
   protected void setUp() throws Exception {
      broker = new BrokerService();
      broker.setPersistent(false);

      // workaround is to ensure sufficient dispatch buffer for the destination
      PolicyMap policyMap = new PolicyMap();
      PolicyEntry defaultPolicy = new PolicyEntry();
      defaultPolicy.setMaxPageSize(testSize);
      policyMap.setDefaultEntry(defaultPolicy);
      broker.setDestinationPolicy(policyMap);
      broker.start();

      super.setUp();
      this.producerConnection = this.createConnection();
      this.consumerConnection = this.createConnection();
   }

   /**
    * @see junit.framework.TestCase#tearDown()
    */
   @Override
   protected void tearDown() throws Exception {
      if (producerConnection != null) {
         producerConnection.close();
         producerConnection = null;
      }
      if (consumerConnection != null) {
         consumerConnection.close();
         consumerConnection = null;
      }
      super.tearDown();
      broker.stop();
   }

   /**
    * Test to check if a single consumer with no JMS selector will receive all intended messages
    *
    * @throws java.lang.Exception
    */
   public void testNonDiscriminatingConsumer() throws Exception {

      consumerConnection = createConnection();
      consumerConnection.start();
      LOG.info("consumerConnection = " + consumerConnection);

      try {
         Thread.sleep(1000);
      }
      catch (Exception e) {
      }

      // here we pass in null for the JMS selector
      Consumer consumer = new Consumer(consumerConnection, null);
      Thread consumerThread = new Thread(consumer);

      consumerThread.start();

      producerConnection = createConnection();
      producerConnection.start();
      LOG.info("producerConnection = " + producerConnection);

      try {
         Thread.sleep(3000);
      }
      catch (Exception e) {
      }

      Producer producer = new Producer(producerConnection);
      Thread producerThread = new Thread(producer);
      producerThread.start();

      // now that everything is running, let's wait for the consumer thread to finish ...
      consumerThread.join();
      producer.stop = true;

      if (consumer.getCount() == testSize)
         LOG.info("test complete .... all messsages consumed!!");
      else
         LOG.info("test failed .... Sent " + (testSize / 1) + " messages intended to be consumed ( " + testSize + " total), but only consumed " + consumer.getCount());

      assertTrue("Sent " + testSize + " messages intended to be consumed, but only consumed " + consumer.getCount(), (consumer.getCount() == testSize));
      assertFalse("Delivery of messages to consumer was halted during this test", consumer.deliveryHalted());
   }

   /**
    * Test to check if a single consumer with a JMS selector will receive all intended messages
    *
    * @throws java.lang.Exception
    */
   public void testDiscriminatingConsumer() throws Exception {

      consumerConnection = createConnection();
      consumerConnection.start();
      LOG.info("consumerConnection = " + consumerConnection);

      try {
         Thread.sleep(1000);
      }
      catch (Exception e) {
      }

      // here we pass the JMS selector we intend to consume
      Consumer consumer = new Consumer(consumerConnection, JMSTYPE_EATME);
      Thread consumerThread = new Thread(consumer);

      consumerThread.start();

      producerConnection = createConnection();
      producerConnection.start();
      LOG.info("producerConnection = " + producerConnection);

      try {
         Thread.sleep(3000);
      }
      catch (Exception e) {
      }

      Producer producer = new Producer(producerConnection);
      Thread producerThread = new Thread(producer);
      producerThread.start();

      // now that everything is running, let's wait for the consumer thread to finish ...
      consumerThread.join();
      producer.stop = true;

      if (consumer.getCount() == (testSize / 2)) {
         LOG.info("test complete .... all messsages consumed!!");
      }
      else {
         LOG.info("test failed .... Sent " + testSize + " original messages, only half of which (" + (testSize / 2) + ") were intended to be consumed: consumer paused at: " + consumer.getCount());
         // System.out.println("test failed .... Sent " + testSize + " original messages, only half of which (" +
         // (testSize / 2) +
         // ") were intended to be consumed: consumer paused at: " + consumer.getCount());

      }

      assertTrue("Sent " + testSize + " original messages, only half of which (" + (testSize / 2) + ") were intended to be consumed: consumer paused at: " + consumer.getCount(), (consumer.getCount() == (testSize / 2)));
      assertTrue("Delivery of messages to consumer was halted during this test as it only wants half", consumer.deliveryHalted());
   }

   /**
    * Helper class that will publish 2 * testSize messages. The messages will be distributed evenly between the
    * following two JMS types:
    *
    * @see JMSTYPE_INTENDED_FOR_CONSUMPTION
    * @see JMSTYPE_NOT_INTENDED_FOR_CONSUMPTION
    */
   private class Producer extends Thread {

      private int counterSent = 0;
      private Connection connection = null;
      public boolean stop = false;

      public Producer(Connection connection) {
         this.connection = connection;
      }

      @Override
      public void run() {
         try {
            final Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
            final Queue queue = session.createQueue("test");

            // wait for 10 seconds to allow consumer.receive to be run
            // first
            Thread.sleep(10000);
            MessageProducer producer = session.createProducer(queue);

            while (!stop && (counterSent < testSize)) {
               // first send a message intended to be consumed ....
               TextMessage message = session.createTextMessage("*** Ill ....... Ini ***"); // alma mater ...
               message.setJMSType(JMSTYPE_EATME);
               // LOG.info("sending .... JMSType = " + message.getJMSType());
               producer.send(message, DeliveryMode.NON_PERSISTENT, 0, 1800000);

               counterSent++;

               // now send a message intended to be consumed by some other consumer in the the future
               // ... we expect these messages to accrue in the queue
               message = session.createTextMessage("*** Ill ....... Ini ***"); // alma mater ...
               message.setJMSType(JMSTYPE_IGNOREME);
               // LOG.info("sending .... JMSType = " + message.getJMSType());
               producer.send(message, DeliveryMode.NON_PERSISTENT, 0, 1800000);

               counterSent++;
            }

            session.close();

         }
         catch (Exception e) {
            e.printStackTrace();
         }
         LOG.info("producer thread complete ... " + counterSent + " messages sent to the queue");
      }
   }

   /**
    * Helper class that will consume messages from the queue based on the supplied JMS selector. Thread will stop after
    * the first receive(..) timeout, or once all expected messages have been received (see testSize). If the thread
    * stops due to a timeout, it is experiencing the delivery pause that is symptomatic of a bug in the broker.
    */
   private class Consumer extends Thread {

      protected int counterReceived = 0;
      private String jmsSelector = null;
      private boolean deliveryHalted = false;

      public Consumer(Connection connection, String jmsSelector) {
         this.jmsSelector = jmsSelector;
      }

      @Override
      public void run() {
         try {
            Session session = consumerConnection.createSession(false, Session.AUTO_ACKNOWLEDGE);
            final Queue queue = session.createQueue("test");
            MessageConsumer consumer = null;
            if (null != this.jmsSelector) {
               consumer = session.createConsumer(queue, "JMSType='" + this.jmsSelector + "'");
            }
            else {
               consumer = session.createConsumer(queue);
            }

            while (!deliveryHalted && (counterReceived < testSize)) {
               TextMessage result = (TextMessage) consumer.receive(30000);
               if (result != null) {
                  counterReceived++;
                  // System.out.println("consuming .... JMSType = " + result.getJMSType() + " received = " +
                  // counterReceived);
                  LOG.info("consuming .... JMSType = " + result.getJMSType() + " received = " + counterReceived);
               }
               else {
                  LOG.info("consuming .... timeout while waiting for a message ... broker must have stopped delivery ...  received = " + counterReceived);
                  deliveryHalted = true;
               }
            }
            session.close();
         }
         catch (Exception e) {
            e.printStackTrace();
         }

      }

      public int getCount() {
         return this.counterReceived;
      }

      public boolean deliveryHalted() {
         return this.deliveryHalted;
      }
   }

}
