/**
 *   GRANITE DATA SERVICES
 *   Copyright (C) 2006-2013 GRANITE DATA SERVICES S.A.S.
 *
 *   This file is part of the Granite Data Services Platform.
 *
 *                               ***
 *
 *   Community License: GPL 3.0
 *
 *   This file is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published
 *   by the Free Software Foundation, either version 3 of the License,
 *   or (at your option) any later version.
 *
 *   This file is distributed in the hope that it will be useful, but
 *   WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program. If not, see <http://www.gnu.org/licenses/>.
 *
 *                               ***
 *
 *   Available Commercial License: GraniteDS SLA 1.0
 *
 *   This is the appropriate option if you are creating proprietary
 *   applications and you are not prepared to distribute and share the
 *   source code of your application under the GPL v3 license.
 *
 *   Please visit http://www.granitedataservices.com/license for more
 *   details.
 */
package org.granite.client.collection;

import java.util.Collection;
import java.util.Iterator;
import java.util.Set;

import org.granite.client.collection.CollectionChangeListener;
import org.granite.client.collection.CollectionChangeSupport;
import org.granite.client.collection.CollectionChangeEvent.Kind;

/**
 * @author William DRAI
 */
public class ObservableSet<E> implements Set<E> {
        
        protected CollectionChangeSupport ccs = new CollectionChangeSupport(this);
        private final Set<E> wrappedSet;
        
        public ObservableSet(Set<E> set) {
                this.wrappedSet = set;
        }
        
        protected Set<E> getWrappedList() {
                return wrappedSet;
        }
        
        public void addCollectionChangeListener(CollectionChangeListener listener) {
                ccs.addCollectionChangeListener(listener);
        }
        
        public void removeCollectionChangeListener(CollectionChangeListener listener) {
                ccs.removeCollectionChangeListener(listener);
        }

        @Override
        public boolean add(E element) {
                boolean added = wrappedSet.add(element);
                if (added)
                        ccs.fireCollectionChangeEvent(Kind.ADD, null, new Object[] { element });
                return added;
        }

        @Override
        public boolean addAll(Collection<? extends E> elements) {
                boolean added = wrappedSet.addAll(elements);
                if (added)
                        ccs.fireCollectionChangeEvent(Kind.ADD, null, elements.toArray());
                return added;
        }

        @Override
        public boolean remove(Object element) {
                boolean removed = wrappedSet.remove(element);
                if (removed)
                        ccs.fireCollectionChangeEvent(Kind.REMOVE, null, new Object[] { removed });
                return removed;
        }

        @Override
        public boolean removeAll(Collection<?> collection) {
                boolean removed = false;
                for (Object element : collection) {
                        if (remove(element))
                                removed = true;
                }
                return removed;
        }

        @Override
        public boolean retainAll(Collection<?> collection) {
                boolean changed = false;
                for (Object element : collection) {
                        if (!wrappedSet.contains(element) && remove(element))
                                changed = true;
                }
                return changed;
        }

        @Override
        public void clear() {
                if (wrappedSet.size() == 0)
                        return;
                Object[] elements = wrappedSet.toArray();
                wrappedSet.clear();
                ccs.fireCollectionChangeEvent(Kind.CLEAR, null, elements);              
        }

        @Override
        public boolean contains(Object element) {
                return wrappedSet.contains(element);
        }

        @Override
        public boolean containsAll(Collection<?> collection) {
                return wrappedSet.containsAll(collection);
        }

        @Override
        public boolean isEmpty() {
                return wrappedSet.isEmpty();
        }

        @Override
        public int size() {
                return wrappedSet.size();
        }

        @Override
        public Object[] toArray() {
                return wrappedSet.toArray();
        }

        @Override
        public <T> T[] toArray(T[] array) {
                return wrappedSet.toArray(array);
        }
        
        @Override
        public Iterator<E> iterator() {
                return new IteratorWrapper(wrappedSet.iterator());
        }
        
        
        private class IteratorWrapper implements Iterator<E> {
                
                private final Iterator<E> wrappedIterator;
                private E element;
                
                public IteratorWrapper(Iterator<E> iterator) {
                        this.wrappedIterator = iterator;
                }

                public boolean hasNext() {
                        return wrappedIterator.hasNext();
                }

                public E next() {
                        element = wrappedIterator.next();
                        return element;
                }

                public void remove() {
                        wrappedIterator.remove();
                        ccs.fireCollectionChangeEvent(Kind.REMOVE, null, new Object[] { element });
                }
        }
}