/*

  * Copyright 2007 - 2007 JEuclid, http://jeuclid.sf.net

  * 

  * Licensed 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.

  */

 /* $Id: MathMLSerializer.java,v 2bab6eb875e8 2010/08/11 16:45:50 max $ */

 package net.sourceforge.jeuclid;

 import java.io.StringWriter;

 import javax.annotation.concurrent.ThreadSafe;

 import javax.xml.transform.OutputKeys;

 import javax.xml.transform.Transformer;

 import javax.xml.transform.TransformerException;

 import javax.xml.transform.TransformerFactory;

 import javax.xml.transform.dom.DOMSource;

 import javax.xml.transform.stream.StreamResult;

 import org.apache.commons.logging.Log;

 import org.apache.commons.logging.LogFactory;

 import org.w3c.dom.Node;

 /**

  * Utility class to serialize DOM documents back into Strings.

  * <p>

  * This class can be used to generate String representations for an existing DOM

  * Tree. The functionality is not restricted to JEuclid, and can be used for

  * other DOM trees as well. In this case, you should set the addDoctype

  * parameter to false.

  * 

  * @version $Revision: 2bab6eb875e8 $

  */

 @ThreadSafe

 public final class MathMLSerializer {

     /**

      * Logger for this class

      */

     private static final Log LOGGER = LogFactory.getLog(MathMLSerializer.class);

     private MathMLSerializer() {

         // empty on purpose

     }

     /**

      * Serialize a document back into a String.

      * 

      * @param doc

      *            a DOM model of a document, or a node in a document

      * @param addDoctype

      *            if true, extra attributes such as docType will be set. This

      *            ensures maximum MathML compatibility. Use only with MathML DOM

      *            trees.

      * @param format

      *            if true, result will be nicely formatted.

      * @return the document serialized to a string

      * @see #serializeDocument(Node, boolean, boolean, boolean)

      */

     public static String serializeDocument(final Node doc,

             final boolean addDoctype, final boolean format) {

         return MathMLSerializer.serializeDocument(doc, addDoctype, format,

                 false);

     }

     /**

      * Serialize a document back into a String.

      * 

      * @param doc

      *            a DOM model of a document.

      * @param addDoctype

      *            if true, extra attributes such as docType will be set. This

      *            ensures maximum MathML compatibility. Use only with MathML DOM

      *            trees.

      * @param format

      *            if true, result will be nicely formatted.

      * @param omitXMLDecl

      *            if true, there will be no XML declaration.

      * @return the document serialized to a string

      */

     public static String serializeDocument(final Node doc,

             final boolean addDoctype, final boolean format,

             final boolean omitXMLDecl) {

         final StringWriter writer = new StringWriter();

         try {

             final Transformer transformer = TransformerFactory.newInstance()

                     .newTransformer();

             final DOMSource source = new DOMSource(doc);

             final StreamResult result = new StreamResult(writer);

             if (addDoctype) {

                 transformer.setOutputProperty(OutputKeys.DOCTYPE_PUBLIC,

                         ResourceEntityResolver.MML2_PUBLICID);

                 transformer.setOutputProperty(OutputKeys.DOCTYPE_SYSTEM,

                         ResourceEntityResolver.MML2_SYSTEMID);

                 transformer.setOutputProperty(OutputKeys.MEDIA_TYPE,

                         Constants.MATHML_MIMETYPE);

             }

             MathMLSerializer.boolToProperty(format, OutputKeys.INDENT,

                     transformer);

             MathMLSerializer.boolToProperty(omitXMLDecl,

                     OutputKeys.OMIT_XML_DECLARATION, transformer);

             transformer.transform(source, result);

         } catch (final TransformerException e) {

             MathMLSerializer.LOGGER.warn(e.getMessage(), e);

         }

         return writer.toString();

     }

     private static void boolToProperty(final boolean bool, final String key,

             final Transformer transformer) {

         if (bool) {

             transformer.setOutputProperty(key, "yes");

         } else {

             transformer.setOutputProperty(key, "no");

         }

     }

 }