/*
 *
 *  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 com.adobe.internal.fxg.dom;

import static com.adobe.fxg.FXGConstants.*;

import com.adobe.fxg.FXGException;
import com.adobe.fxg.dom.FXGNode;

/**
 * The mask property node is a special delegate that associates a mask with a
 * parent graphic content node. 
 * 
 * @author Peter Farland
 */
public class MaskPropertyNode extends DelegateNode
{
    
    /** The mask. */
    public MaskingNode mask;

    //--------------------------------------------------------------------------
    //
    // FXGNode Implementation
    //
    //--------------------------------------------------------------------------

    /**
     * @return The unqualified name of a mask node, without tag markup.
     */
    public String getNodeName()
    {
        return FXG_MASK_ELEMENT;
    }

    /**
     * Adds an FXG child node to this mask property node. Supported child nodes
     * include MaskingNode. An exception is thrown if a mask is already defined.
     * 
     * @param child - a child FXG node to be added to this node.
     * @throws FXGException if the child is not supported by this node.
     * @see com.adobe.internal.fxg.dom.DelegateNode#addChild(com.adobe.fxg.dom.FXGNode)
     */
    public void addChild(FXGNode child)
    {
        if (mask == null && child instanceof MaskingNode)
        {
            mask = (MaskingNode)child;
            delegate.addChild(this);
        }
        else
        {
            super.addChild(child);
        }
    }
}