/**
 * Copyright (c) 2005, www.pdfbox.org
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. Neither the name of pdfbox; nor the names of its
 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
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 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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 * http://www.pdfbox.org
 *
 */
package org.pdfbox.util.operator;

import org.apache.log4j.Logger;
import org.pdfbox.cos.COSName;
import org.pdfbox.cos.COSStream;
import org.pdfbox.pdmodel.PDPage;
import org.pdfbox.pdmodel.PDResources;
import org.pdfbox.pdmodel.graphics.xobject.PDXObject;
import org.pdfbox.pdmodel.graphics.xobject.PDXObjectForm;
import org.pdfbox.util.PDFOperator;

import java.io.IOException;
import java.util.List;
import java.util.Set;
import java.util.TreeSet;
import java.util.Map;

/**
 * Invoke named XObject.
 * 
 * @author Ben Litchfield (ben@benlitchfield.com)
 * @author Mario Ivankovits
 * 
 * @version $Revision: 1.6 $
 */
public class Invoke extends OperatorProcessor
{
    private static final Logger LOG = Logger.getLogger(Invoke.class);

    private Set inProcess = new TreeSet();

    /**
     * process : Do - Invoke a named xobject.
     * @param operator The operator that is being executed.
     * @param arguments List
     *
     * @throws IOException If there is an error processing this operator.
     */
    public void process(PDFOperator operator, List arguments) throws IOException
    {
        COSName name = (COSName) arguments.get( 0 );
        if (LOG.isDebugEnabled())
        {
            LOG.debug("<Do name=\"" + name.getName() + "\">");
        }

        // wprinz: allow recursive processing so that nested xobject forms are correctly dealt with
//        if (inProcess.contains(name))
//        {
//            // avoid recursive loop
//            return;
//        }
        // /wprinz

        inProcess.add(name);

        try
        {
            //PDResources res = context.getResources();

            Map xobjects = context.getXObjects();
            PDXObject xobject = (PDXObject) xobjects.get(name.getName());

            if(xobject instanceof PDXObjectForm)
            {
                PDXObjectForm form = (PDXObjectForm)xobject;
                COSStream invoke = (COSStream)form.getCOSObject();
                PDResources pdResources = form.getResources();
                PDPage page = context.getCurrentPage();
                if(pdResources == null)
                {
                    pdResources = page.findResources();
                }

                getContext().processSubStream( page, pdResources, invoke );
            }
        }
        finally
        {
            inProcess.remove(name);
        }
    }
}