/*
 *                 Sun Public License Notice
 * 
 * The contents of this file are subject to the Sun Public License
 * Version 1.0 (the "License"). You may not use this file except in
 * compliance with the License. A copy of the License is available at
 * http://www.sun.com/
 * 
 * The Original Code is NetBeans. The Initial Developer of the Original
 * Code is Sun Microsystems, Inc. Portions Copyright 1997-2003 Sun
 * Microsystems, Inc. All Rights Reserved.
 */
package org.netbeans.modules.xml.tree.children;

import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.util.Collection;
import java.util.LinkedList;

import org.netbeans.tax.*;

/**
 * @author  Libor Kramolis
 * @version 0.1
 */
public class SubObjectListChildren extends ObjectListChildren {

    /** sub list or null (that degrates it to ObjectListChildren) */
    private final TreeObjectList subObjectList;

    /** */
    private final ObjectListListener olListener;

    /** */
    private boolean wasEmpty;

    //
    // init
    //

    /** */
    public SubObjectListChildren (TreeObjectList objectList, TreeObjectList subObjectList, Class[] groupTypes) {
        super (objectList, groupTypes);

        this.olListener    = new ObjectListListener();
        this.subObjectList = subObjectList;
    }

    
    //
    // from Children.Keys
    //

    /**
     */
    protected void addNotify () {
        if ( this.subObjectList != null ) {
            this.subObjectList.addPropertyChangeListener (olListener);
        }

        super.addNotify();
    }

    /*
     * Removes listener
     */
    protected void removeNotify () {
        if ( this.subObjectList != null ) {
            this.subObjectList.removePropertyChangeListener (olListener);
        }
        
        super.removeNotify();
    }


    //
    // itself
    //

    /**
     */
    protected Collection createKeys () {
        if ( Util.THIS.isLoggable() ) /* then */ Util.THIS.debug ("SubObjectListChildren::createKeys"); // NOI18N

        Collection keys;
        Collection superKeys = super.createKeys();

        if (subObjectList != null) {
            if ( wasEmpty = subObjectList.isEmpty() ) {
                keys = superKeys;
            } else {
                keys = new LinkedList ();
                keys.add (new InstanceKey (subObjectList));
                keys.addAll (superKeys);
            }
        } else {
            keys = superKeys;
        }

        if ( Util.THIS.isLoggable() ) /* then */ Util.THIS.debug ("                     ::createKeys: keys = " + keys); // NOI18N

        return keys;
    }


    //
    // ObjectListListener
    //

    /**
     *
     */
    private class ObjectListListener implements PropertyChangeListener {

        /**
         */
        public void propertyChange (PropertyChangeEvent pche) {
            if ( Util.THIS.isLoggable() ) /* then */ Util.THIS.debug ("SubObjectListChildren::ObjectListListener::propertyChange: propertyName = '" + pche.getPropertyName() + "'"); // NOI18N

            if ( (TreeObjectList.PROP_CONTENT_INSERT.equals (pche.getPropertyName())) ||
                 (TreeObjectList.PROP_CONTENT_REMOVE.equals (pche.getPropertyName())) ) {

                if (SubObjectListChildren.this.subObjectList.isEmpty() != SubObjectListChildren.this.wasEmpty) {
                    SubObjectListChildren.this.refreshKeys();
                }
            }
        }

    } // end: class ObjectListListener

}