/*
    * Copyright (C) 2013 The Guava Authors
    *
    * Licensed 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 com.google.common.collect.testing.google;
  
  import static com.google.common.collect.testing.features.CollectionFeature.SUPPORTS_ITERATOR_REMOVE;
  import static com.google.common.collect.testing.features.CollectionSize.ONE;
  import static com.google.common.collect.testing.features.CollectionSize.ZERO;
  import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_KEYS;
  import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_KEY_QUERIES;
  import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_VALUES;
  import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_VALUE_QUERIES;
  import static com.google.common.collect.testing.features.MapFeature.SUPPORTS_REMOVE;
  import static com.google.common.truth.Truth.assertThat;
  
  import com.google.common.annotations.GwtCompatible;
  import com.google.common.collect.Multimap;
  import com.google.common.collect.testing.Helpers;
  import com.google.common.collect.testing.features.CollectionFeature;
  import com.google.common.collect.testing.features.CollectionSize;
  import com.google.common.collect.testing.features.MapFeature;
  
  import java.util.Collections;
  import java.util.Iterator;
  import java.util.Map.Entry;
  
  /**
   * Tester for {@code Multimap.entries}.
   *
   * @author Louis Wasserman
   */
  @GwtCompatible
  public class MultimapEntriesTester<K, V> extends AbstractMultimapTester<K, V, Multimap<K, V>> {
    public void testEntries() {
      assertThat(multimap().entries()).has().exactlyAs(getSampleElements());
    }
    
    @CollectionSize.Require(absent = ZERO)
    @MapFeature.Require(ALLOWS_NULL_KEYS)
    public void testContainsEntryWithNullKeyPresent() {
      initMultimapWithNullKey();
      assertThat(multimap().entries()).has().allOf(
          Helpers.mapEntry((K) null, getValueForNullKey()));
    }
    
    @MapFeature.Require(ALLOWS_NULL_KEY_QUERIES)
    public void testContainsEntryWithNullKeyAbsent() {
      assertFalse(multimap().entries().contains(Helpers.mapEntry(null, sampleValues().e0)));
    }
    
    @CollectionSize.Require(absent = ZERO)
    @MapFeature.Require(ALLOWS_NULL_VALUES)
    public void testContainsEntryWithNullValuePresent() {
      initMultimapWithNullValue();
      assertThat(multimap().entries()).has().allOf(
          Helpers.mapEntry(getKeyForNullValue(), (V) null));
    }
    
    @MapFeature.Require(ALLOWS_NULL_VALUE_QUERIES)
    public void testContainsEntryWithNullValueAbsent() {
      assertFalse(multimap().entries().contains(
          Helpers.mapEntry(sampleKeys().e0, null)));
    }
    
    @CollectionSize.Require(absent = ZERO)
    @MapFeature.Require(SUPPORTS_REMOVE)
    public void testRemovePropagatesToMultimap() {
      assertTrue(multimap().entries().remove(
          Helpers.mapEntry(sampleKeys().e0, sampleValues().e0)));
      expectMissing(Helpers.mapEntry(sampleKeys().e0, sampleValues().e0));
      assertEquals(getNumElements() - 1, multimap().size());
      assertFalse(multimap().containsEntry(sampleKeys().e0, sampleValues().e0));
    }
    
    @CollectionSize.Require(absent = ZERO)
    @MapFeature.Require(SUPPORTS_REMOVE)
    public void testRemoveAllPropagatesToMultimap() {
      assertTrue(multimap().entries().removeAll(
          Collections.singleton(Helpers.mapEntry(sampleKeys().e0, sampleValues().e0))));
      expectMissing(Helpers.mapEntry(sampleKeys().e0, sampleValues().e0));
      assertEquals(getNumElements() - 1, multimap().size());
      assertFalse(multimap().containsEntry(sampleKeys().e0, sampleValues().e0));
    }
    
    @CollectionSize.Require(absent = ZERO)
    @MapFeature.Require(SUPPORTS_REMOVE)
    public void testRetainAllPropagatesToMultimap() {
      multimap().entries().retainAll(
         Collections.singleton(Helpers.mapEntry(sampleKeys().e0, sampleValues().e0)));
     assertEquals(
         getSubjectGenerator().create(Helpers.mapEntry(sampleKeys().e0, sampleValues().e0)),
         multimap());
     assertEquals(1, multimap().size());
     assertTrue(multimap().containsEntry(sampleKeys().e0, sampleValues().e0));
   }
   
   @CollectionSize.Require(ONE)
   @CollectionFeature.Require(SUPPORTS_ITERATOR_REMOVE)
   public void testIteratorRemovePropagatesToMultimap() {
     Iterator<Entry<K, V>> iterator = multimap().entries().iterator();
     assertEquals(
         Helpers.mapEntry(sampleKeys().e0, sampleValues().e0),
         iterator.next());
     iterator.remove();
     assertTrue(multimap().isEmpty());
   }
   
   @CollectionSize.Require(absent = ZERO)
   @MapFeature.Require(SUPPORTS_REMOVE)
   public void testEntriesRemainValidAfterRemove() {
     Iterator<Entry<K, V>> iterator = multimap().entries().iterator();
     Entry<K, V> entry = iterator.next();
     K key = entry.getKey();
     V value = entry.getValue();
     multimap().removeAll(key);
     assertEquals(key, entry.getKey());
     assertEquals(value, entry.getValue());
   }
 }