/*
    * 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.commons.collections4.multiset;
  
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertFalse;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  import static org.junit.jupiter.api.Assertions.assertTrue;
  
  import java.util.Set;
  
  import org.apache.commons.collections4.MultiSet;
  import org.apache.commons.collections4.Predicate;
  import org.apache.commons.collections4.functors.TruePredicate;
  import org.junit.jupiter.api.Test;
  
  /**
   * Extension of {@link AbstractMultiSetTest} for exercising the
   * {@link PredicatedMultiSet} implementation.
   */
  public class PredicatedMultiSetTest<T> extends AbstractMultiSetTest<T> {
  
      protected Predicate<T> truePredicate = TruePredicate.<T>truePredicate();
  
      protected MultiSet<T> decorateMultiSet(final HashMultiSet<T> multiset, final Predicate<T> predicate) {
          return PredicatedMultiSet.predicatedMultiSet(multiset, predicate);
      }
  
      @Override
      public String getCompatibilityVersion() {
          return "4.1";
      }
  
      @Override
      protected int getIterationBehaviour() {
          return UNORDERED;
      }
  
      @Override
      public MultiSet<T> makeObject() {
          return decorateMultiSet(new HashMultiSet<>(), truePredicate);
      }
  
      protected MultiSet<T> makeTestMultiSet() {
          return decorateMultiSet(new HashMultiSet<>(), stringPredicate());
      }
  
      protected Predicate<T> stringPredicate() {
          return String.class::isInstance;
      }
  
      @Test
      @SuppressWarnings("unchecked")
      public void testIllegalAdd() {
          final MultiSet<T> multiset = makeTestMultiSet();
          final Integer i = Integer.valueOf(3);
          assertThrows(IllegalArgumentException.class, () -> multiset.add((T) i),
                  "Integer should fail string predicate.");
          assertFalse(multiset.contains(i), "Collection shouldn't contain illegal element");
      }
  
      @Test
      @SuppressWarnings("unchecked")
      public void testIllegalDecorate() {
          final HashMultiSet<Object> elements = new HashMultiSet<>();
          elements.add("one");
          elements.add("two");
          elements.add(Integer.valueOf(3));
          elements.add("four");
          assertThrows(IllegalArgumentException.class, () -> decorateMultiSet((HashMultiSet<T>) elements, stringPredicate()),
                  "MultiSet contains an element that should fail the predicate.");
          assertThrows(NullPointerException.class, () -> decorateMultiSet(new HashMultiSet<>(), null),
                  "Expecting NullPointerException for null predicate.");
      }
  
      @Test
      @SuppressWarnings("unchecked")
      public void testLegalAddRemove() {
          final MultiSet<T> multiset = makeTestMultiSet();
          assertEquals(0, multiset.size());
          final T[] els = (T[]) new Object[] { "1", "3", "5", "7", "2", "4", "1" };
          for (int i = 0; i < els.length; i++) {
              multiset.add(els[i]);
              assertEquals(i + 1, multiset.size());
              assertTrue(multiset.contains(els[i]));
         }
         Set<T> set = ((PredicatedMultiSet<T>) multiset).uniqueSet();
         assertTrue(set.contains(els[0]), "Unique set contains the first element");
         assertTrue(multiset.remove(els[0]));
         set = ((PredicatedMultiSet<T>) multiset).uniqueSet();
         assertTrue(set.contains(els[0]),
             "Unique set does not contain anymore the first element");
     }
 
 //    public void testCreate() throws Exception {
 //        MultiSet<T> multiset = makeObject();
 //        writeExternalFormToDisk((java.io.Serializable) multiset, "src/test/resources/data/test/PredicatedMultiSet.emptyCollection.version4.1.obj");
 //        multiset = makeFullCollection();
 //        writeExternalFormToDisk((java.io.Serializable) multiset, "src/test/resources/data/test/PredicatedMultiSet.fullCollection.version4.1.obj");
 //    }
 
 }