/*
 * 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 org.openstreetmap.josm.plugins.pdfimport.pdfbox.operators;

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

import org.apache.pdfbox.cos.COSBase;
import org.apache.pdfbox.cos.COSName;
import org.apache.pdfbox.cos.COSStream;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.PDResources;
import org.apache.pdfbox.pdmodel.graphics.xobject.PDXObject;
import org.apache.pdfbox.pdmodel.graphics.xobject.PDXObjectForm;
import org.apache.pdfbox.pdmodel.graphics.xobject.PDXObjectImage;
import org.apache.pdfbox.util.Matrix;
import org.apache.pdfbox.util.PDFOperator;
import org.apache.pdfbox.util.operator.OperatorProcessor;
import org.openstreetmap.josm.plugins.pdfimport.pdfbox.PageDrawer;

/**
 * Implementation of content stream operator for page drawer.
 *
 * @author <a href="mailto:ben@benlitchfield.com">Ben Litchfield</a>
 * @version $Revision: 1.4 $
 */
public class Invoke extends OperatorProcessor
{


    /**
     * process : Do : Paint the specified XObject (section 4.7).
     * @param operator The operator that is being executed.
     * @param arguments List
     * @throws IOException If there is an error invoking the sub object.
     */
    @Override
    public void process(PDFOperator operator, List<COSBase> arguments) throws IOException
    {
        PageDrawer drawer = (PageDrawer)context;
        PDPage page = drawer.getPage();
        COSName objectName = (COSName)arguments.get( 0 );
        Map<?, ?> xobjects = drawer.getResources().getXObjects();
        PDXObject xobject = (PDXObject)xobjects.get( objectName.getName() );
        if( xobject instanceof PDXObjectImage )
        {
            drawer.drawImage();
        }
        else if(xobject instanceof PDXObjectForm)
        {
            PDXObjectForm form = (PDXObjectForm)xobject;
            COSStream invoke = (COSStream)form.getCOSObject();
            PDResources pdResources = form.getResources();
            if(pdResources == null)
            {
                pdResources = page.findResources();
            }
            // if there is an optional form matrix, we have to
            // map the form space to the user space
            Matrix matrix = form.getMatrix();
            if (matrix != null)
            {
                Matrix xobjectCTM = matrix.multiply( context.getGraphicsState().getCurrentTransformationMatrix());
                context.getGraphicsState().setCurrentTransformationMatrix(xobjectCTM);
            }
            getContext().processSubStream( page, pdResources, invoke );
        }
        else
        {
            //unknown xobject type
        }


        //invoke named object.
    }
}
