pdfbox-trunk/pdfbox/src/main/java/org/apache/pdfbox/pdmodel/fdf/FDFCatalog.java
/*
 * 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.pdmodel.fdf;

import java.io.IOException;
import java.io.Writer;

import org.apache.pdfbox.cos.COSDictionary;
import org.apache.pdfbox.cos.COSName;
import org.apache.pdfbox.pdmodel.common.COSObjectable;
import org.apache.pdfbox.pdmodel.interactive.digitalsignature.PDSignature;
import org.w3c.dom.Element;

/**
 * This represents an FDF catalog that is part of the FDF document.
 *
 * @author Ben Litchfield
 */
public class FDFCatalog implements COSObjectable
{
    private final COSDictionary catalog;

    /**
     * Default constructor.
     */
    public FDFCatalog()
    {
        catalog = new COSDictionary();
    }

    /**
     * Constructor.
     *
     * @param cat The FDF documents catalog.
     */
    public FDFCatalog(COSDictionary cat)
    {
        catalog = cat;
    }

    /**
     * This will create an FDF catalog from an XFDF XML document.
     *
     * @param element The XML document that contains the XFDF data.
     */
    public FDFCatalog(Element element)
    {
        this();
        FDFDictionary fdfDict = new FDFDictionary(element);
        setFDF(fdfDict);
    }

    /**
     * This will write this element as an XML document.
     *
     * @param output The stream to write the xml to.
     *
     * @throws IOException If there is an error writing the XML.
     */
    public void writeXML(Writer output) throws IOException
    {
        FDFDictionary fdf = getFDF();
        fdf.writeXML(output);
    }

    /**
     * Convert this standard java object to a COS object.
     *
     * @return The cos object that matches this Java object.
     */
    @Override
    public COSDictionary getCOSObject()
    {
        return catalog;
    }

    /**
     * This will get the version that was specified in the catalog dictionary.
     *
     * @return The FDF version.
     */
    public String getVersion()
    {
        return catalog.getNameAsString(COSName.VERSION);
    }

    /**
     * This will set the version of the FDF document.
     *
     * @param version The new version for the FDF document.
     */
    public void setVersion(String version)
    {
        catalog.setName(COSName.VERSION, version);
    }

    /**
     * This will get the FDF dictionary.
     *
     * @return The FDF dictionary.
     */
    public FDFDictionary getFDF()
    {
        COSDictionary fdf = catalog.getCOSDictionary(COSName.FDF);
        FDFDictionary retval;
        if (fdf != null)
        {
            retval = new FDFDictionary(fdf);
        }
        else
        {
            retval = new FDFDictionary();
            setFDF(retval);
        }
        return retval;
    }

    /**
     * This will set the FDF document.
     *
     * @param fdf The new FDF dictionary.
     */
    public final void setFDF(FDFDictionary fdf)
    {
        catalog.setItem(COSName.FDF, fdf);
    }

    /**
     * This will get the signature or null if there is none.
     *
     * @return The signature.
     */
    public PDSignature getSignature()
    {
        COSDictionary sig = catalog.getCOSDictionary(COSName.SIG);
        return sig != null ? new PDSignature(sig) : null;
    }

    /**
     * This will set the signature that is associated with this catalog.
     *
     * @param sig The new signature.
     */
    public void setSignature(PDSignature sig)
    {
        catalog.setItem(COSName.SIG, sig);
    }
}
