/*
    * Copyright (C) 2012 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.Helpers.assertContentsAnyOrder;
  import static com.google.common.collect.testing.features.CollectionSize.SEVERAL;
  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.SUPPORTS_PUT;
  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.CollectionSize;
  import com.google.common.collect.testing.features.MapFeature;
  
  import java.util.Collection;
  import java.util.Collections;
  
  /**
   * Tests for {@link Multimap#get(Object)}.
   *
   * @author Louis Wasserman
   */
  @GwtCompatible
  public class MultimapGetTester<K, V> extends AbstractMultimapTester<K, V, Multimap<K, V>> {
    public void testGetEmpty() {
      Collection<V> result = multimap().get(sampleKeys().e3);
      assertTrue(result.isEmpty());
      assertEquals(0, result.size());
    }
    
    @CollectionSize.Require(absent = ZERO)
    public void testGetNonEmpty() {
      Collection<V> result = multimap().get(sampleKeys().e0);
      assertFalse(result.isEmpty());
      assertContentsAnyOrder(result, sampleValues().e0);
    }
  
    @CollectionSize.Require(SEVERAL)
    public void testGetMultiple() {
      resetContainer(
          Helpers.mapEntry(sampleKeys().e0, sampleValues().e0),
          Helpers.mapEntry(sampleKeys().e0, sampleValues().e1),
          Helpers.mapEntry(sampleKeys().e0, sampleValues().e2));
      assertGet(sampleKeys().e0,
          sampleValues().e0,
          sampleValues().e1,
          sampleValues().e2);
    }
    
    public void testGetAbsentKey() {
      assertGet(sampleKeys().e4);
    }
    
    @CollectionSize.Require(SEVERAL)
    @MapFeature.Require(SUPPORTS_REMOVE)
    public void testPropagatesRemoveToMultimap() {
      resetContainer(
          Helpers.mapEntry(sampleKeys().e0, sampleValues().e0),
          Helpers.mapEntry(sampleKeys().e0, sampleValues().e3),
          Helpers.mapEntry(sampleKeys().e0, sampleValues().e2));
      Collection<V> result = multimap().get(sampleKeys().e0);
      assertTrue(result.remove(sampleValues().e0));
      assertFalse(multimap().containsEntry(sampleKeys().e0, sampleValues().e0));
      assertEquals(2, multimap().size());
    }
  
    @CollectionSize.Require(absent = ZERO)
    @MapFeature.Require(SUPPORTS_REMOVE)
    public void testPropagatesRemoveLastElementToMultimap() {
      Collection<V> result = multimap().get(sampleKeys().e0);
      assertTrue(result.remove(sampleValues().e0));
      assertGet(sampleKeys().e0);
    }  
  
    @MapFeature.Require(SUPPORTS_PUT)
    public void testPropagatesAddToMultimap() {
      Collection<V> result = multimap().get(sampleKeys().e0);
      assertTrue(result.add(sampleValues().e3));
      assertTrue(multimap().containsKey(sampleKeys().e0));
      assertEquals(getNumElements() + 1, multimap().size());
     assertTrue(multimap().containsEntry(sampleKeys().e0, sampleValues().e3));
   }
 
   @MapFeature.Require(SUPPORTS_PUT)
   public void testPropagatesAddAllToMultimap() {
     Collection<V> result = multimap().get(sampleKeys().e0);
     assertTrue(result.addAll(Collections.singletonList(sampleValues().e3)));
     assertTrue(multimap().containsKey(sampleKeys().e0));
     assertEquals(getNumElements() + 1, multimap().size());
     assertTrue(multimap().containsEntry(sampleKeys().e0, sampleValues().e3));
   }
 
   @CollectionSize.Require(absent = ZERO)
   @MapFeature.Require({ SUPPORTS_REMOVE, SUPPORTS_PUT })
   public void testPropagatesRemoveLastThenAddToMultimap() {
     int oldSize = getNumElements();
 
     K k0 = sampleKeys().e0;
     V v0 = sampleValues().e0;
 
     Collection<V> result = multimap().get(k0);
     assertTrue(result.remove(v0));
 
     assertFalse(multimap().containsKey(k0));
     assertFalse(multimap().containsEntry(k0, v0));
     assertThat(result).isEmpty();
 
     V v1 = sampleValues().e1;
     V v2 = sampleValues().e2;
 
     assertTrue(result.add(v1));
     assertTrue(result.add(v2));
 
     assertThat(result).has().exactly(v1, v2);
     assertThat(multimap().get(k0)).has().exactly(v1, v2);
     assertTrue(multimap().containsKey(k0));
     assertFalse(multimap().containsEntry(k0, v0));
     assertTrue(multimap().containsEntry(k0, v2));
     assertEquals(oldSize + 1, multimap().size());
   }
 
   @MapFeature.Require(ALLOWS_NULL_KEYS)
   @CollectionSize.Require(absent = ZERO)
   public void testGetNullPresent() {
     initMultimapWithNullKey();
     assertThat(multimap().get(null)).has().item(getValueForNullKey());
   }
 
   @MapFeature.Require(ALLOWS_NULL_KEY_QUERIES)
   public void testGetNullAbsent() {
     assertThat(multimap().get(null)).isEmpty();
   }
 
   @MapFeature.Require(absent = ALLOWS_NULL_KEY_QUERIES)
   public void testGetNullForbidden() {
     try {
       multimap().get(null);
       fail("Expected NullPointerException");
     } catch (NullPointerException expected) {
       // success
     }
   }
 
   @MapFeature.Require(ALLOWS_NULL_VALUES)
   @CollectionSize.Require(absent = ZERO)
   public void testGetWithNullValue() {
     initMultimapWithNullValue();
     assertThat(multimap().get(getKeyForNullValue()))
         .has().item(null);
   }
 }