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/*
 * Copyright (c) 2021 Goldman Sachs.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * and Eclipse Distribution License v. 1.0 which accompany this distribution.
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 */

package org.eclipse.collections.impl.utility.internal;

import java.lang.reflect.Constructor;
import java.lang.reflect.Proxy;
import java.util.Collection;
import java.util.PriorityQueue;
import java.util.Set;
import java.util.SortedSet;
import java.util.concurrent.PriorityBlockingQueue;

import org.eclipse.collections.api.collection.MutableCollection;
import org.eclipse.collections.api.factory.Lists;
import org.eclipse.collections.api.factory.Sets;

public class DefaultSpeciesNewStrategy
{
    public static final DefaultSpeciesNewStrategy INSTANCE = new DefaultSpeciesNewStrategy();
    private static final Class[] SIZE_CONSTRUCTOR_TYPES = {int.class};

    // todo - Consider behaviour for adapters, eg.:
    //         - SetAdapter.adapt(new TreeSet(orderingComparator))
    //         - SetAdapter.adapt(hibernateCollectionProxy)

    /**
     * Creates a new instance of a collection based on the class type of collection, not on the type of objects the collections contains.
     * e.g. {@code CollectionFactory.speciesNew(hashSetOfString)} returns a new {@code HashSet()};
     * e.g. {@code CollectionFactory.speciesNew(linkedListOfWombles)} returns a new {@code LinkedList()};
     */
    public  Collection speciesNew(Collection collection)
    {
        if (collection instanceof MutableCollection)
        {
            return ((MutableCollection) collection).newEmpty();
        }
        if (collection instanceof Proxy)
        {
            return DefaultSpeciesNewStrategy.createNewInstanceForCollectionType(collection);
        }
        if (ReflectionHelper.hasDefaultConstructor(collection.getClass()))
        {
            return (Collection) ReflectionHelper.newInstance(collection.getClass());
        }
        return DefaultSpeciesNewStrategy.createNewInstanceForCollectionType(collection);
    }

    /**
     * Creates a new instance of a collection based on the class type of collection and specified initial capacity,
     * not on the type of objects the collections contains.
     * e.g. {@code CollectionFactory.speciesNew(hashSetOfString, 20)} returns a new {@code HashSet(20)};
     * e.g. {@code CollectionFactory.speciesNew(linkedListOfWombles, 42)} returns a new {@code LinkedList(42)};
     */
    public  Collection speciesNew(Collection collection, int size)
    {
        if (size < 0)
        {
            throw new IllegalArgumentException("size may not be < 0 but was " + size);
        }

        if (collection instanceof Proxy
                || collection instanceof PriorityQueue
                || collection instanceof PriorityBlockingQueue
                || collection instanceof SortedSet)
        {
            return DefaultSpeciesNewStrategy.createNewInstanceForCollectionType(collection);
        }
        Constructor constructor = ReflectionHelper.getConstructor(collection.getClass(), SIZE_CONSTRUCTOR_TYPES);
        if (constructor != null)
        {
            return (Collection) ReflectionHelper.newInstance(constructor, size);
        }
        return this.speciesNew(collection);
    }

    private static  Collection createNewInstanceForCollectionType(Collection collection)
    {
        if (collection instanceof SortedSet
                || collection instanceof PriorityQueue
                || collection instanceof PriorityBlockingQueue)
        {
            return Lists.mutable.empty();
        }
        if (collection instanceof Set)
        {
            return Sets.mutable.empty();
        }
        return Lists.mutable.empty();
    }
}