/**
 * 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.broker.region.cursors;

import java.util.Collection;
import java.util.Iterator;
import java.util.LinkedList;

import org.apache.activemq.broker.region.Destination;
import org.apache.activemq.broker.region.MessageReference;
import org.apache.activemq.command.ConsumerId;
import org.apache.activemq.command.Message;
import org.apache.activemq.command.MessageId;
import org.apache.activemq.util.IdGenerator;
import org.junit.Test;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;

public class OrderPendingListTest {

   @Test
   public void testAddMessageFirst() throws Exception {

      OrderedPendingList list = new OrderedPendingList();

      list.addMessageFirst(new TestMessageReference(1));
      list.addMessageFirst(new TestMessageReference(2));
      list.addMessageFirst(new TestMessageReference(3));
      list.addMessageFirst(new TestMessageReference(4));
      list.addMessageFirst(new TestMessageReference(5));

      assertTrue(list.size() == 5);
      assertEquals(5, list.getAsList().size());

      Iterator<MessageReference> iter = list.iterator();
      int lastId = list.size();
      while (iter.hasNext()) {
         assertEquals(lastId--, iter.next().getMessageId().getProducerSequenceId());
      }
   }

   @Test
   public void testAddMessageLast() throws Exception {

      OrderedPendingList list = new OrderedPendingList();

      list.addMessageLast(new TestMessageReference(1));
      list.addMessageLast(new TestMessageReference(2));
      list.addMessageLast(new TestMessageReference(3));
      list.addMessageLast(new TestMessageReference(4));
      list.addMessageLast(new TestMessageReference(5));

      assertTrue(list.size() == 5);
      assertEquals(5, list.getAsList().size());

      Iterator<MessageReference> iter = list.iterator();
      int lastId = 1;
      while (iter.hasNext()) {
         assertEquals(lastId++, iter.next().getMessageId().getProducerSequenceId());
      }
   }

   @Test
   public void testClear() throws Exception {
      OrderedPendingList list = new OrderedPendingList();

      list.addMessageFirst(new TestMessageReference(1));
      list.addMessageFirst(new TestMessageReference(2));
      list.addMessageFirst(new TestMessageReference(3));
      list.addMessageFirst(new TestMessageReference(4));
      list.addMessageFirst(new TestMessageReference(5));

      assertFalse(list.isEmpty());
      assertTrue(list.size() == 5);
      assertEquals(5, list.getAsList().size());

      list.clear();

      assertTrue(list.isEmpty());
      assertTrue(list.size() == 0);
      assertEquals(0, list.getAsList().size());

      list.addMessageFirst(new TestMessageReference(1));
      list.addMessageLast(new TestMessageReference(2));
      list.addMessageLast(new TestMessageReference(3));
      list.addMessageFirst(new TestMessageReference(4));
      list.addMessageLast(new TestMessageReference(5));

      assertFalse(list.isEmpty());
      assertTrue(list.size() == 5);
      assertEquals(5, list.getAsList().size());
   }

   @Test
   public void testIsEmpty() throws Exception {
      OrderedPendingList list = new OrderedPendingList();
      assertTrue(list.isEmpty());

      list.addMessageFirst(new TestMessageReference(1));
      list.addMessageFirst(new TestMessageReference(2));
      list.addMessageFirst(new TestMessageReference(3));
      list.addMessageFirst(new TestMessageReference(4));
      list.addMessageFirst(new TestMessageReference(5));

      assertFalse(list.isEmpty());
      list.clear();
      assertTrue(list.isEmpty());
   }

   @Test
   public void testSize() {
      OrderedPendingList list = new OrderedPendingList();
      assertTrue(list.isEmpty());

      assertTrue(list.size() == 0);
      list.addMessageFirst(new TestMessageReference(1));
      assertTrue(list.size() == 1);
      list.addMessageLast(new TestMessageReference(2));
      assertTrue(list.size() == 2);
      list.addMessageFirst(new TestMessageReference(3));
      assertTrue(list.size() == 3);
      list.addMessageLast(new TestMessageReference(4));
      assertTrue(list.size() == 4);
      list.addMessageFirst(new TestMessageReference(5));
      assertTrue(list.size() == 5);

      assertFalse(list.isEmpty());
      list.clear();
      assertTrue(list.isEmpty());
      assertTrue(list.size() == 0);
   }

   @Test
   public void testRemove() throws Exception {

      OrderedPendingList list = new OrderedPendingList();

      TestMessageReference toRemove = new TestMessageReference(6);

      list.addMessageFirst(new TestMessageReference(1));
      list.addMessageFirst(new TestMessageReference(2));
      list.addMessageFirst(new TestMessageReference(3));
      list.addMessageFirst(new TestMessageReference(4));
      list.addMessageFirst(new TestMessageReference(5));

      assertTrue(list.size() == 5);
      assertEquals(5, list.getAsList().size());

      list.addMessageLast(toRemove);
      list.remove(toRemove);

      assertTrue(list.size() == 5);
      assertEquals(5, list.getAsList().size());

      list.remove(toRemove);

      assertTrue(list.size() == 5);
      assertEquals(5, list.getAsList().size());

      Iterator<MessageReference> iter = list.iterator();
      int lastId = list.size();
      while (iter.hasNext()) {
         assertEquals(lastId--, iter.next().getMessageId().getProducerSequenceId());
      }

      list.remove(null);
   }

   @Test
   public void testContains() throws Exception {

      OrderedPendingList list = new OrderedPendingList();

      TestMessageReference toRemove = new TestMessageReference(6);

      assertFalse(list.contains(toRemove));
      assertFalse(list.contains(null));

      list.addMessageFirst(new TestMessageReference(1));
      list.addMessageFirst(new TestMessageReference(2));
      list.addMessageFirst(new TestMessageReference(3));
      list.addMessageFirst(new TestMessageReference(4));
      list.addMessageFirst(new TestMessageReference(5));

      assertTrue(list.size() == 5);
      assertEquals(5, list.getAsList().size());

      list.addMessageLast(toRemove);
      assertTrue(list.size() == 6);
      assertTrue(list.contains(toRemove));
      list.remove(toRemove);
      assertFalse(list.contains(toRemove));

      assertTrue(list.size() == 5);
      assertEquals(5, list.getAsList().size());
   }

   @Test
   public void testValues() throws Exception {

      OrderedPendingList list = new OrderedPendingList();

      TestMessageReference toRemove = new TestMessageReference(6);

      assertFalse(list.contains(toRemove));

      list.addMessageFirst(new TestMessageReference(1));
      list.addMessageFirst(new TestMessageReference(2));
      list.addMessageFirst(new TestMessageReference(3));
      list.addMessageFirst(new TestMessageReference(4));
      list.addMessageFirst(new TestMessageReference(5));

      Collection<MessageReference> values = list.values();
      assertEquals(5, values.size());

      for (MessageReference msg : values) {
         assertTrue(values.contains(msg));
      }

      assertFalse(values.contains(toRemove));

      list.addMessageLast(toRemove);
      values = list.values();
      assertEquals(6, values.size());
      for (MessageReference msg : values) {
         assertTrue(values.contains(msg));
      }

      assertTrue(values.contains(toRemove));
   }

   @Test
   public void testAddAll() throws Exception {
      OrderedPendingList list = new OrderedPendingList();
      TestPendingList source = new TestPendingList();

      source.addMessageFirst(new TestMessageReference(1));
      source.addMessageFirst(new TestMessageReference(2));
      source.addMessageFirst(new TestMessageReference(3));
      source.addMessageFirst(new TestMessageReference(4));
      source.addMessageFirst(new TestMessageReference(5));

      assertTrue(list.isEmpty());
      assertEquals(5, source.size());
      list.addAll(source);
      assertEquals(5, list.size());

      for (MessageReference message : source) {
         assertTrue(list.contains(message));
      }

      list.addAll(null);
   }

   static class TestPendingList implements PendingList {

      private final LinkedList<MessageReference> theList = new LinkedList<>();

      @Override
      public long messageSize() {
         return 0;
      }

      @Override
      public boolean isEmpty() {
         return theList.isEmpty();
      }

      @Override
      public void clear() {
         theList.clear();
      }

      @Override
      public PendingNode addMessageFirst(MessageReference message) {
         theList.addFirst(message);
         return new PendingNode(null, message);
      }

      @Override
      public PendingNode addMessageLast(MessageReference message) {
         theList.addLast(message);
         return new PendingNode(null, message);
      }

      @Override
      public PendingNode remove(MessageReference message) {
         if (theList.remove(message)) {
            return new PendingNode(null, message);
         } else {
            return null;
         }
      }

      @Override
      public int size() {
         return theList.size();
      }

      @Override
      public Iterator<MessageReference> iterator() {
         return theList.iterator();
      }

      @Override
      public boolean contains(MessageReference message) {
         return theList.contains(message);
      }

      @Override
      public Collection<MessageReference> values() {
         return theList;
      }

      @Override
      public void addAll(PendingList pendingList) {
         for (MessageReference messageReference : pendingList) {
            theList.add(messageReference);
         }
      }

      @Override
      public MessageReference get(MessageId messageId) {
         for (MessageReference messageReference : theList) {
            if (messageReference.getMessageId().equals(messageId)) {
               return messageReference;
            }
         }
         return null;
      }
   }

   static class TestMessageReference implements MessageReference {

      private static final IdGenerator id = new IdGenerator();

      private MessageId messageId;
      private int referenceCount = 0;

      public TestMessageReference(int sequenceId) {
         messageId = new MessageId(id.generateId() + ":1", sequenceId);
      }

      @Override
      public boolean canProcessAsExpired() {
         return false;
      }

      @Override
      public MessageId getMessageId() {
         return messageId;
      }

      @Override
      public Message getMessageHardRef() {
         return null;
      }

      @Override
      public Message getMessage() {
         return null;
      }

      @Override
      public boolean isPersistent() {
         return false;
      }

      @Override
      public Destination getRegionDestination() {
         return null;
      }

      @Override
      public int getRedeliveryCounter() {
         return 0;
      }

      @Override
      public void incrementRedeliveryCounter() {
      }

      @Override
      public int getReferenceCount() {
         return this.referenceCount;
      }

      @Override
      public int incrementReferenceCount() {
         return this.referenceCount++;
      }

      @Override
      public int decrementReferenceCount() {
         return this.referenceCount--;
      }

      @Override
      public ConsumerId getTargetConsumerId() {
         return null;
      }

      @Override
      public int getSize() {
         return 1;
      }

      @Override
      public long getExpiration() {
         return 0;
      }

      @Override
      public String getGroupID() {
         return null;
      }

      @Override
      public int getGroupSequence() {
         return 0;
      }

      @Override
      public boolean isExpired() {
         return false;
      }

      @Override
      public boolean isDropped() {
         return false;
      }

      @Override
      public boolean isAdvisory() {
         return false;
      }
   }
}
