/*
    * 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.set;
  
  import java.util.Iterator;
  import java.util.NavigableSet;
  
  import org.apache.commons.collections4.Transformer;
  
  /**
   * Decorates another {@code NavigableSet} to transform objects that are added.
   * <p>
   * The add methods are affected by this class.
   * Thus objects must be removed or searched for using their transformed form.
   * For example, if the transformation converts Strings to Integers, you must
   * use the Integer form to remove objects.
   * </p>
   *
   * @param <E> the type of the elements in this set
   * @since 4.1
   */
  public class TransformedNavigableSet<E> extends TransformedSortedSet<E> implements NavigableSet<E> {
  
      /** Serialization version */
      private static final long serialVersionUID = 20150528L;
  
      /**
       * Factory method to create a transforming navigable set that will transform
       * existing contents of the specified navigable set.
       * <p>
       * If there are any elements already in the set being decorated, they
       * will be transformed by this method.
       * Contrast this with {@link #transformingNavigableSet(NavigableSet, Transformer)}.
       *
       * @param <E> the element type
       * @param set  the set to decorate, must not be null
       * @param transformer  the transformer to use for conversion, must not be null
       * @return a new transformed {@link NavigableSet}
       * @throws NullPointerException if set or transformer is null
       */
      public static <E> TransformedNavigableSet<E> transformedNavigableSet(final NavigableSet<E> set,
              final Transformer<? super E, ? extends E> transformer) {
  
          final TransformedNavigableSet<E> decorated = new TransformedNavigableSet<>(set, transformer);
          if (!set.isEmpty()) {
              @SuppressWarnings("unchecked") // set is type E
              final E[] values = (E[]) set.toArray(); // NOPMD - false positive for generics
              set.clear();
              for (final E value : values) {
                  decorated.decorated().add(transformer.apply(value));
              }
          }
          return decorated;
      }
  
      /**
       * Factory method to create a transforming navigable set.
       * <p>
       * If there are any elements already in the set being decorated, they
       * are NOT transformed.
       * Contrast this with {@link #transformedNavigableSet(NavigableSet, Transformer)}.
       *
       * @param <E> the element type
       * @param set  the set to decorate, must not be null
       * @param transformer  the transformer to use for conversion, must not be null
       * @return a new transformed {@link NavigableSet}
       * @throws NullPointerException if set or transformer is null
       */
      public static <E> TransformedNavigableSet<E> transformingNavigableSet(final NavigableSet<E> set,
              final Transformer<? super E, ? extends E> transformer) {
          return new TransformedNavigableSet<>(set, transformer);
      }
  
      /**
       * Constructor that wraps (not copies).
       * <p>
       * If there are any elements already in the set being decorated, they
       * are NOT transformed.
       *
       * @param set  the set to decorate, must not be null
       * @param transformer  the transformer to use for conversion, must not be null
       * @throws NullPointerException if set or transformer is null
       */
      protected TransformedNavigableSet(final NavigableSet<E> set,
                                        final Transformer<? super E, ? extends E> transformer) {
         super(set, transformer);
     }
 
     @Override
     public E ceiling(final E e) {
         return decorated().ceiling(e);
     }
 
     /**
      * Gets the decorated navigable set.
      *
      * @return the decorated navigable set
      */
     @Override
     protected NavigableSet<E> decorated() {
         return (NavigableSet<E>) super.decorated();
     }
 
     @Override
     public Iterator<E> descendingIterator() {
         return decorated().descendingIterator();
     }
 
     @Override
     public NavigableSet<E> descendingSet() {
         return transformingNavigableSet(decorated().descendingSet(), transformer);
     }
 
     @Override
     public E floor(final E e) {
         return decorated().floor(e);
     }
 
     @Override
     public NavigableSet<E> headSet(final E toElement, final boolean inclusive) {
         final NavigableSet<E> head = decorated().headSet(toElement, inclusive);
         return transformingNavigableSet(head, transformer);
     }
 
     @Override
     public E higher(final E e) {
         return decorated().higher(e);
     }
 
     @Override
     public E lower(final E e) {
         return decorated().lower(e);
     }
 
     @Override
     public E pollFirst() {
         return decorated().pollFirst();
     }
 
     @Override
     public E pollLast() {
         return decorated().pollLast();
     }
 
     @Override
     public NavigableSet<E> subSet(final E fromElement, final boolean fromInclusive, final E toElement,
             final boolean toInclusive) {
         final NavigableSet<E> sub = decorated().subSet(fromElement, fromInclusive, toElement, toInclusive);
         return transformingNavigableSet(sub, transformer);
     }
 
     @Override
     public NavigableSet<E> tailSet(final E fromElement, final boolean inclusive) {
         final NavigableSet<E> tail = decorated().tailSet(fromElement, inclusive);
         return transformingNavigableSet(tail, transformer);
     }
 
 }