/*

 * 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</code> 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.

     * <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);

    }

    /**

     * 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.size() > 0) {

            @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.transform(value));

            }

        }

        return decorated;

    }

    //-----------------------------------------------------------------------

    /**

     * 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);

    }

    /**

     * Gets the decorated set.

     *

     * @return the decorated set

     */

    protected SortedSet<E> getSortedSet() {

        return (SortedSet<E>) decorated();

    }

    //-----------------------------------------------------------------------

    @Override

    public E first() {

        return getSortedSet().first();

    }

    @Override

    public E last() {

        return getSortedSet().last();

    }

    @Override

    public Comparator<? super E> comparator() {

        return getSortedSet().comparator();

    }

    //-----------------------------------------------------------------------

    @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> headSet(final E toElement) {

        final SortedSet<E> set = getSortedSet().headSet(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);

    }

}