/**
 * 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.bugs;

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;
import javax.jms.Connection;
import javax.jms.DeliveryMode;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageConsumer;
import javax.jms.MessageListener;
import javax.jms.MessageProducer;
import javax.jms.Session;
import javax.jms.TextMessage;

import org.apache.activemq.ActiveMQConnectionFactory;
import org.apache.activemq.broker.BrokerService;
import org.apache.activemq.broker.region.policy.ConstantPendingMessageLimitStrategy;
import org.apache.activemq.broker.region.policy.OldestMessageEvictionStrategy;
import org.apache.activemq.broker.region.policy.PolicyEntry;
import org.apache.activemq.broker.region.policy.PolicyMap;
import org.apache.activemq.command.ActiveMQTopic;
import org.junit.Assert;
import org.junit.Test;

/**
 * @author James Furness
 *         https://issues.apache.org/jira/browse/AMQ-3607
 */
public class ActiveMQSlowConsumerManualTest {

   private static final int PORT = 12345;
   private static final ActiveMQTopic TOPIC = new ActiveMQTopic("TOPIC");
   private static final String URL = "nio://localhost:" + PORT + "?socket.tcpNoDelay=true";

   @Test(timeout = 60000)
   public void testDefaultSettings() throws Exception {
      runTest("testDefaultSettings", 30, -1, -1, false, false, false, false);
   }

   @Test(timeout = 60000)
   public void testDefaultSettingsWithOptimiseAcknowledge() throws Exception {
      runTest("testDefaultSettingsWithOptimiseAcknowledge", 30, -1, -1, false, false, true, false);
   }

   @Test(timeout = 60000)
   public void testBounded() throws Exception {
      runTest("testBounded", 30, 5, 25, false, false, false, false);
   }

   @Test(timeout = 60000)
   public void testBoundedWithOptimiseAcknowledge() throws Exception {
      runTest("testBoundedWithOptimiseAcknowledge", 30, 5, 25, false, false, true, false);
   }

   public void runTest(String name,
                       int sendMessageCount,
                       int prefetchLimit,
                       int messageLimit,
                       boolean evictOldestMessage,
                       boolean disableFlowControl,
                       boolean optimizeAcknowledge,
                       boolean persistent) throws Exception {
      BrokerService broker = createBroker(persistent);
      broker.setDestinationPolicy(buildPolicy(TOPIC, prefetchLimit, messageLimit, evictOldestMessage, disableFlowControl));
      broker.start();

      // Slow consumer
      Session slowConsumerSession = buildSession("SlowConsumer", URL, optimizeAcknowledge);
      final CountDownLatch blockSlowConsumer = new CountDownLatch(1);
      final AtomicInteger slowConsumerReceiveCount = new AtomicInteger();
      final List<Integer> slowConsumerReceived = sendMessageCount <= 1000 ? new ArrayList<Integer>() : null;
      MessageConsumer slowConsumer = createSubscriber(slowConsumerSession, new MessageListener() {
                                                         @Override
                                                         public void onMessage(Message message) {
                                                            try {
                                                               slowConsumerReceiveCount.incrementAndGet();
                                                               int count = Integer.parseInt(((TextMessage) message).getText());
                                                               if (slowConsumerReceived != null)
                                                                  slowConsumerReceived.add(count);
                                                               if (count % 10000 == 0)
                                                                  System.out.println("SlowConsumer: Receive " + count);
                                                               blockSlowConsumer.await();
                                                            }
                                                            catch (Exception ignored) {
                                                            }
                                                         }
                                                      });

      // Fast consumer
      Session fastConsumerSession = buildSession("FastConsumer", URL, optimizeAcknowledge);
      final AtomicInteger fastConsumerReceiveCount = new AtomicInteger();
      final List<Integer> fastConsumerReceived = sendMessageCount <= 1000 ? new ArrayList<Integer>() : null;
      MessageConsumer fastConsumer = createSubscriber(fastConsumerSession, new MessageListener() {
                                                         @Override
                                                         public void onMessage(Message message) {
                                                            try {
                                                               fastConsumerReceiveCount.incrementAndGet();
                                                               TimeUnit.MILLISECONDS.sleep(5);
                                                               int count = Integer.parseInt(((TextMessage) message).getText());
                                                               if (fastConsumerReceived != null)
                                                                  fastConsumerReceived.add(count);
                                                               if (count % 10000 == 0)
                                                                  System.out.println("FastConsumer: Receive " + count);
                                                            }
                                                            catch (Exception ignored) {
                                                            }
                                                         }
                                                      });

      // Wait for consumers to connect
      Thread.sleep(500);

      // Publisher
      AtomicInteger sentCount = new AtomicInteger();
      List<Integer> sent = sendMessageCount <= 1000 ? new ArrayList<Integer>() : null;
      Session publisherSession = buildSession("Publisher", URL, optimizeAcknowledge);
      MessageProducer publisher = createPublisher(publisherSession);
      for (int i = 0; i < sendMessageCount; i++) {
         sentCount.incrementAndGet();
         if (sent != null)
            sent.add(i);
         if (i % 10000 == 0)
            System.out.println("Publisher: Send " + i);
         publisher.send(publisherSession.createTextMessage(Integer.toString(i)));
      }

      // Wait for messages to arrive
      Thread.sleep(500);

      System.out.println(name + ": Publisher Sent: " + sentCount + " " + sent);
      System.out.println(name + ": Whilst slow consumer blocked:");
      System.out.println("\t\t- SlowConsumer Received: " + slowConsumerReceiveCount + " " + slowConsumerReceived);
      System.out.println("\t\t- FastConsumer Received: " + fastConsumerReceiveCount + " " + fastConsumerReceived);

      // Unblock slow consumer
      blockSlowConsumer.countDown();

      // Wait for messages to arrive
      Thread.sleep(500);

      System.out.println(name + ": After slow consumer unblocked:");
      System.out.println("\t\t- SlowConsumer Received: " + slowConsumerReceiveCount + " " + slowConsumerReceived);
      System.out.println("\t\t- FastConsumer Received: " + fastConsumerReceiveCount + " " + fastConsumerReceived);
      System.out.println();

      publisher.close();
      publisherSession.close();
      slowConsumer.close();
      slowConsumerSession.close();
      fastConsumer.close();
      fastConsumerSession.close();
      broker.stop();

      Assert.assertEquals("Fast consumer missed messages whilst slow consumer was blocking", sent, fastConsumerReceived);
      // this is too timine dependent  as sometimes there is message eviction, would need to check the dlq
      //Assert.assertEquals("Slow consumer received incorrect message count", Math.min(sendMessageCount, prefetchLimit + (messageLimit > 0 ? messageLimit : Integer.MAX_VALUE)), slowConsumerReceived.size());
   }

   private static BrokerService createBroker(boolean persistent) throws Exception {
      BrokerService broker = new BrokerService();
      broker.setBrokerName("TestBroker");
      broker.setPersistent(persistent);
      broker.addConnector(URL);
      return broker;
   }

   private static MessageConsumer createSubscriber(Session session,
                                                   MessageListener messageListener) throws JMSException {
      MessageConsumer consumer = session.createConsumer(TOPIC);
      consumer.setMessageListener(messageListener);
      return consumer;
   }

   private static MessageProducer createPublisher(Session session) throws JMSException {
      MessageProducer producer = session.createProducer(TOPIC);
      producer.setDeliveryMode(DeliveryMode.NON_PERSISTENT);
      return producer;
   }

   private static Session buildSession(String clientId, String url, boolean optimizeAcknowledge) throws JMSException {
      ActiveMQConnectionFactory connectionFactory = new ActiveMQConnectionFactory(url);

      connectionFactory.setCopyMessageOnSend(false);
      connectionFactory.setDisableTimeStampsByDefault(true);
      connectionFactory.setOptimizeAcknowledge(optimizeAcknowledge);
      if (optimizeAcknowledge) {
         connectionFactory.setOptimizeAcknowledgeTimeOut(1);
      }

      Connection connection = connectionFactory.createConnection();
      connection.setClientID(clientId);

      Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);

      connection.start();

      return session;
   }

   private static PolicyMap buildPolicy(ActiveMQTopic topic,
                                        int prefetchLimit,
                                        int messageLimit,
                                        boolean evictOldestMessage,
                                        boolean disableFlowControl) {
      PolicyMap policyMap = new PolicyMap();

      PolicyEntry policyEntry = new PolicyEntry();

      if (evictOldestMessage) {
         policyEntry.setMessageEvictionStrategy(new OldestMessageEvictionStrategy());
      }

      if (disableFlowControl) {
         policyEntry.setProducerFlowControl(false);
      }

      if (prefetchLimit > 0) {
         policyEntry.setTopicPrefetch(prefetchLimit);
      }

      if (messageLimit > 0) {
         ConstantPendingMessageLimitStrategy messageLimitStrategy = new ConstantPendingMessageLimitStrategy();
         messageLimitStrategy.setLimit(messageLimit);
         policyEntry.setPendingMessageLimitStrategy(messageLimitStrategy);
      }

      policyMap.put(topic, policyEntry);

      return policyMap;
   }
}