/*
    * 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.Comparator;
  import java.util.SortedSet;
  
  import org.apache.commons.collections4.Transformer;
  
  /**
   * Decorates another {@code SortedSet} 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>
   * <p>
   * This class is Serializable from Commons Collections 3.1.
   * </p>
   *
   * @param <E> the type of the elements in this set
   * @since 3.0
   */
  public class TransformedSortedSet<E> extends TransformedSet<E> implements SortedSet<E> {
  
      /** Serialization version */
      private static final long serialVersionUID = -1675486811351124386L;
  
      /**
       * Factory method to create a transforming sorted set that will transform
       * existing contents of the specified sorted set.
       * <p>
       * If there are any elements already in the set being decorated, they
       * will be transformed by this method.
       * Contrast this with {@link #transformingSortedSet(SortedSet, 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 SortedSet}
       * @throws NullPointerException if set or transformer is null
       * @since 4.0
       */
      public static <E> TransformedSortedSet<E> transformedSortedSet(final SortedSet<E> set,
              final Transformer<? super E, ? extends E> transformer) {
  
          final TransformedSortedSet<E> decorated = new TransformedSortedSet<>(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 sorted set.
       * <p>
       * If there are any elements already in the set being decorated, they
       * are NOT transformed.
       * Contrast this with {@link #transformedSortedSet(SortedSet, 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 SortedSet}
       * @throws NullPointerException if set or transformer is null
       * @since 4.0
       */
      public static <E> TransformedSortedSet<E> transformingSortedSet(final SortedSet<E> set,
              final Transformer<? super E, ? extends E> transformer) {
          return new TransformedSortedSet<>(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 TransformedSortedSet(final SortedSet<E> set, final Transformer<? super E, ? extends E> transformer) {
         super(set, transformer);
     }
 
     @Override
     public Comparator<? super E> comparator() {
         return getSortedSet().comparator();
     }
 
     @Override
     public E first() {
         return getSortedSet().first();
     }
 
     /**
      * Gets the decorated set.
      *
      * @return the decorated set
      */
     protected SortedSet<E> getSortedSet() {
         return (SortedSet<E>) decorated();
     }
 
     @Override
     public SortedSet<E> headSet(final E toElement) {
         final SortedSet<E> set = getSortedSet().headSet(toElement);
         return new TransformedSortedSet<>(set, transformer);
     }
 
     @Override
     public E last() {
         return getSortedSet().last();
     }
 
     @Override
     public SortedSet<E> subSet(final E fromElement, final E toElement) {
         final SortedSet<E> set = getSortedSet().subSet(fromElement, toElement);
         return new TransformedSortedSet<>(set, transformer);
     }
 
     @Override
     public SortedSet<E> tailSet(final E fromElement) {
         final SortedSet<E> set = getSortedSet().tailSet(fromElement);
         return new TransformedSortedSet<>(set, transformer);
     }
 
 }