/*
* 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.apache.pdfbox.multipdf;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.pdfbox.cos.COSArray;
import org.apache.pdfbox.cos.COSBase;
import org.apache.pdfbox.cos.COSDictionary;
import org.apache.pdfbox.cos.COSName;
import org.apache.pdfbox.cos.COSObject;
import org.apache.pdfbox.cos.COSStream;
import org.apache.pdfbox.io.IOUtils;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.common.COSObjectable;
/**
* Utility class used to clone PDF objects. It keeps track of objects it has already cloned.
*
*/
public class PDFCloneUtility
{
private final PDDocument destination;
private final Map<Object,COSBase> clonedVersion = new HashMap<>();
/**
* Creates a new instance for the given target document.
* @param dest the destination PDF document that will receive the clones
*/
public PDFCloneUtility(PDDocument dest)
{
this.destination = dest;
}
/**
* Returns the destination PDF document this cloner instance is set up for.
* @return the destination PDF document
*/
public PDDocument getDestination()
{
return this.destination;
}
/**
* Deep-clones the given object for inclusion into a different PDF document identified by
* the destination parameter.
* @param base the initial object as the root of the deep-clone operation
* @return the cloned instance of the base object
* @throws IOException if an I/O error occurs
*/
public COSBase cloneForNewDocument( Object base ) throws IOException
{
if( base == null )
{
return null;
}
COSBase retval = clonedVersion.get(base);
if( retval != null )
{
//we are done, it has already been converted.
}
else if( base instanceof List)
{
COSArray array = new COSArray();
List<?> list = (List<?>) base;
for (Object obj : list)
{
array.add(cloneForNewDocument(obj));
}
retval = array;
}
else if( base instanceof COSObjectable && !(base instanceof COSBase) )
{
retval = cloneForNewDocument( ((COSObjectable)base).getCOSObject() );
clonedVersion.put( base, retval );
}
else if( base instanceof COSObject )
{
COSObject object = (COSObject)base;
retval = cloneForNewDocument( object.getObject() );
clonedVersion.put( base, retval );
}
else if( base instanceof COSArray )
{
COSArray newArray = new COSArray();
COSArray array = (COSArray)base;
for( int i=0; i<array.size(); i++ )
{
newArray.add( cloneForNewDocument( array.get( i ) ) );
}
retval = newArray;
clonedVersion.put( base, retval );
}
else if( base instanceof COSStream )
{
COSStream originalStream = (COSStream)base;
COSStream stream = destination.getDocument().createCOSStream();
try (OutputStream output = stream.createRawOutputStream();
InputStream input = originalStream.createRawInputStream())
{
IOUtils.copy(input, output);
}
clonedVersion.put( base, stream );
for( Map.Entry<COSName, COSBase> entry : originalStream.entrySet() )
{
stream.setItem(entry.getKey(), cloneForNewDocument(entry.getValue()));
}
retval = stream;
}
else if( base instanceof COSDictionary )
{
COSDictionary dic = (COSDictionary)base;
retval = new COSDictionary();
clonedVersion.put( base, retval );
for( Map.Entry<COSName, COSBase> entry : dic.entrySet() )
{
((COSDictionary)retval).setItem(
entry.getKey(),
cloneForNewDocument(entry.getValue()));
}
}
else
{
retval = (COSBase)base;
}
clonedVersion.put( base, retval );
return retval;
}
/**
* Merges two objects of the same type by deep-cloning its members.
* <br>
* Base and target must be instances of the same class.
* @param base the base object to be cloned
* @param target the merge target
* @throws IOException if an I/O error occurs
*/
public void cloneMerge( final COSObjectable base, COSObjectable target) throws IOException
{
if( base == null )
{
return;
}
COSBase retval = clonedVersion.get( base );
if( retval != null )
{
return;
//we are done, it has already been converted. // ### Is that correct for cloneMerge???
}
else if (!(base instanceof COSBase))
{
cloneMerge(base.getCOSObject(), target.getCOSObject());
clonedVersion.put(base, retval);
}
else if( base instanceof COSObject )
{
if(target instanceof COSObject)
{
cloneMerge(((COSObject) base).getObject(),((COSObject) target).getObject() );
}
else if(target instanceof COSDictionary)
{
cloneMerge(((COSObject) base).getObject(), target);
}
clonedVersion.put( base, retval );
}
else if( base instanceof COSArray )
{
COSArray array = (COSArray)base;
for( int i=0; i<array.size(); i++ )
{
((COSArray)target).add( cloneForNewDocument( array.get( i ) ) );
}
clonedVersion.put( base, retval );
}
else if( base instanceof COSStream )
{
// does that make sense???
COSStream originalStream = (COSStream)base;
COSStream stream = destination.getDocument().createCOSStream();
try (OutputStream output = stream.createOutputStream(originalStream.getFilters()))
{
IOUtils.copy(originalStream.createInputStream(), output);
}
clonedVersion.put( base, stream );
for( Map.Entry<COSName, COSBase> entry : originalStream.entrySet() )
{
stream.setItem(entry.getKey(), cloneForNewDocument(entry.getValue()));
}
retval = stream;
}
else if( base instanceof COSDictionary )
{
COSDictionary dic = (COSDictionary)base;
clonedVersion.put( base, retval );
for( Map.Entry<COSName, COSBase> entry : dic.entrySet() )
{
COSName key = entry.getKey();
COSBase value = entry.getValue();
if (((COSDictionary)target).getItem(key) != null)
{
cloneMerge(value, ((COSDictionary)target).getItem(key));
}
else
{
((COSDictionary)target).setItem( key, cloneForNewDocument(value));
}
}
}
else
{
retval = (COSBase)base;
}
clonedVersion.put( base, retval );
}
}