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	/*
	* reserved comment block
	* DO NOT REMOVE OR ALTER!
	*/
	/*
	* 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 com.sun.org.apache.xml.internal.dtm.ref;

	import com.sun.org.apache.xml.internal.dtm.DTM;
	import com.sun.org.apache.xml.internal.utils.NodeConsumer;
	import com.sun.org.apache.xml.internal.utils.XMLString;

	import org.xml.sax.ContentHandler;
	import org.xml.sax.ext.LexicalHandler;

	/**
	* This class does a pre-order walk of the DTM tree, calling a ContentHandler
	* interface as it goes. As such, it's more like the Visitor design pattern
	* than like the DOM's TreeWalker.
	*
	* I think normally this class should not be needed, because
	* of DTM#dispatchToEvents.
	* @xsl.usage advanced
	*/
	public class DTMTreeWalker
	{

	/** Local reference to a ContentHandler */
	private ContentHandler m_contentHandler = null;

	/** DomHelper for this TreeWalker */
	protected DTM m_dtm;

	/**
	* Set the DTM to be traversed.
	*
	* @param dtm The Document Table Model to be used.
	*/
	public void setDTM(DTM dtm)
	{
	m_dtm = dtm;
	}

	/**
	* Get the ContentHandler used for the tree walk.
	*
	* @return the ContentHandler used for the tree walk
	*/
	public ContentHandler getcontentHandler()
	{
	return m_contentHandler;
	}

	/**
	* Set the ContentHandler used for the tree walk.
	*
	* @param ch the ContentHandler to be the result of the tree walk.
	*/
	public void setcontentHandler(ContentHandler ch)
	{
	m_contentHandler = ch;
	}


	/**
	* Constructor.
	*/
	public DTMTreeWalker()
	{
	}

	/**
	* Constructor.
	* @param contentHandler The implemention of the
	* contentHandler operation (toXMLString, digest, ...)
	*/
	public DTMTreeWalker(ContentHandler contentHandler, DTM dtm)
	{
	this.m_contentHandler = contentHandler;
	m_dtm = dtm;
	}

	/** Perform a non-recursive pre-order/post-order traversal,
	* operating as a Visitor. startNode (preorder) and endNode
	* (postorder) are invoked for each node as we traverse over them,
	* with the result that the node is written out to m_contentHandler.
	*
	* @param pos Node in the tree at which to start (and end) traversal --
	* in other words, the root of the subtree to traverse over.
	*
	* @throws TransformerException */
	public void traverse(int pos) throws org.xml.sax.SAXException
	{
	// %REVIEW% Why isn't this just traverse(pos,pos)?

	int top = pos; // Remember the root of this subtree

	while (DTM.NULL != pos)
	{
	startNode(pos);
	int nextNode = m_dtm.getFirstChild(pos);
	while (DTM.NULL == nextNode)
	{
	endNode(pos);

	if (top == pos)
	break;

	nextNode = m_dtm.getNextSibling(pos);

	if (DTM.NULL == nextNode)
	{
	pos = m_dtm.getParent(pos);

	if ((DTM.NULL == pos) \|\| (top == pos))
	{
	// %REVIEW% This condition isn't tested in traverse(pos,top)
	// -- bug?
	if (DTM.NULL != pos)
	endNode(pos);

	nextNode = DTM.NULL;

	break;
	}
	}
	}

	pos = nextNode;
	}
	}

	/** Perform a non-recursive pre-order/post-order traversal,
	* operating as a Visitor. startNode (preorder) and endNode
	* (postorder) are invoked for each node as we traverse over them,
	* with the result that the node is written out to m_contentHandler.
	*
	* @param pos Node in the tree where to start traversal
	* @param top Node in the tree where to end traversal.
	* If top==DTM.NULL, run through end of document.
	*
	* @throws TransformerException
	*/
	public void traverse(int pos, int top) throws org.xml.sax.SAXException
	{
	// %OPT% Can we simplify the loop conditionals by adding:
	// if(top==DTM.NULL) top=0
	// -- or by simply ignoring this case and relying on the fact that
	// pos will never equal DTM.NULL until we're ready to exit?

	while (DTM.NULL != pos)
	{
	startNode(pos);
	int nextNode = m_dtm.getFirstChild(pos);
	while (DTM.NULL == nextNode)
	{
	endNode(pos);

	if ((DTM.NULL != top) && top == pos)
	break;

	nextNode = m_dtm.getNextSibling(pos);

	if (DTM.NULL == nextNode)
	{
	pos = m_dtm.getParent(pos);

	if ((DTM.NULL == pos) \|\| ((DTM.NULL != top) && (top == pos)))
	{
	nextNode = DTM.NULL;

	break;
	}
	}
	}

	pos = nextNode;
	}
	}

	/** Flag indicating whether following text to be processed is raw text */
	boolean nextIsRaw = false;

	/**
	* Optimized dispatch of characters.
	*/
	private final void dispatachChars(int node)
	throws org.xml.sax.SAXException
	{
	m_dtm.dispatchCharactersEvents(node, m_contentHandler, false);
	}

	/**
	* Start processing given node
	*
	*
	* @param node Node to process
	*
	* @throws org.xml.sax.SAXException
	*/
	protected void startNode(int node) throws org.xml.sax.SAXException
	{

	if (m_contentHandler instanceof NodeConsumer)
	{
	// %TBD%
	// ((NodeConsumer) m_contentHandler).setOriginatingNode(node);
	}

	switch (m_dtm.getNodeType(node))
	{
	case DTM.COMMENT_NODE :
	{
	XMLString data = m_dtm.getStringValue(node);

	if (m_contentHandler instanceof LexicalHandler)
	{
	LexicalHandler lh = ((LexicalHandler) this.m_contentHandler);
	data.dispatchAsComment(lh);
	}
	}
	break;
	case DTM.DOCUMENT_FRAGMENT_NODE :

	// ??;
	break;
	case DTM.DOCUMENT_NODE :
	this.m_contentHandler.startDocument();
	break;
	case DTM.ELEMENT_NODE :
	DTM dtm = m_dtm;

	for (int nsn = dtm.getFirstNamespaceNode(node, true); DTM.NULL != nsn;
	nsn = dtm.getNextNamespaceNode(node, nsn, true))
	{
	// String prefix = dtm.getPrefix(nsn);
	String prefix = dtm.getNodeNameX(nsn);

	this.m_contentHandler.startPrefixMapping(prefix, dtm.getNodeValue(nsn));

	}

	// System.out.println("m_dh.getNamespaceOfNode(node): "+m_dh.getNamespaceOfNode(node));
	// System.out.println("m_dh.getLocalNameOfNode(node): "+m_dh.getLocalNameOfNode(node));
	String ns = dtm.getNamespaceURI(node);
	if(null == ns)
	ns = "";

	// %OPT% !!
	org.xml.sax.helpers.AttributesImpl attrs =
	new org.xml.sax.helpers.AttributesImpl();

	for (int i = dtm.getFirstAttribute(node);
	i != DTM.NULL;
	i = dtm.getNextAttribute(i))
	{
	attrs.addAttribute(dtm.getNamespaceURI(i),
	dtm.getLocalName(i),
	dtm.getNodeName(i),
	"CDATA",
	dtm.getNodeValue(i));
	}


	this.m_contentHandler.startElement(ns,
	m_dtm.getLocalName(node),
	m_dtm.getNodeName(node),
	attrs);
	break;
	case DTM.PROCESSING_INSTRUCTION_NODE :
	{
	String name = m_dtm.getNodeName(node);

	// String data = pi.getData();
	if (name.equals("xslt-next-is-raw"))
	{
	nextIsRaw = true;
	}
	else
	{
	this.m_contentHandler.processingInstruction(name,
	m_dtm.getNodeValue(node));
	}
	}
	break;
	case DTM.CDATA_SECTION_NODE :
	{
	boolean isLexH = (m_contentHandler instanceof LexicalHandler);
	LexicalHandler lh = isLexH
	? ((LexicalHandler) this.m_contentHandler) : null;

	if (isLexH)
	{
	lh.startCDATA();
	}

	dispatachChars(node);

	{
	if (isLexH)
	{
	lh.endCDATA();
	}
	}
	}
	break;
	case DTM.TEXT_NODE :
	{
	if (nextIsRaw)
	{
	nextIsRaw = false;

	m_contentHandler.processingInstruction(javax.xml.transform.Result.PI_DISABLE_OUTPUT_ESCAPING, "");
	dispatachChars(node);
	m_contentHandler.processingInstruction(javax.xml.transform.Result.PI_ENABLE_OUTPUT_ESCAPING, "");
	}
	else
	{
	dispatachChars(node);
	}
	}
	break;
	case DTM.ENTITY_REFERENCE_NODE :
	{
	if (m_contentHandler instanceof LexicalHandler)
	{
	((LexicalHandler) this.m_contentHandler).startEntity(
	m_dtm.getNodeName(node));
	}
	else
	{

	// warning("Can not output entity to a pure SAX ContentHandler");
	}
	}
	break;
	default :
	}
	}

	/**
	* End processing of given node
	*
	*
	* @param node Node we just finished processing
	*
	* @throws org.xml.sax.SAXException
	*/
	protected void endNode(int node) throws org.xml.sax.SAXException
	{

	switch (m_dtm.getNodeType(node))
	{
	case DTM.DOCUMENT_NODE :
	this.m_contentHandler.endDocument();
	break;
	case DTM.ELEMENT_NODE :
	String ns = m_dtm.getNamespaceURI(node);
	if(null == ns)
	ns = "";
	this.m_contentHandler.endElement(ns,
	m_dtm.getLocalName(node),
	m_dtm.getNodeName(node));

	for (int nsn = m_dtm.getFirstNamespaceNode(node, true); DTM.NULL != nsn;
	nsn = m_dtm.getNextNamespaceNode(node, nsn, true))
	{
	// String prefix = m_dtm.getPrefix(nsn);
	String prefix = m_dtm.getNodeNameX(nsn);

	this.m_contentHandler.endPrefixMapping(prefix);
	}
	break;
	case DTM.CDATA_SECTION_NODE :
	break;
	case DTM.ENTITY_REFERENCE_NODE :
	{
	if (m_contentHandler instanceof LexicalHandler)
	{
	LexicalHandler lh = ((LexicalHandler) this.m_contentHandler);

	lh.endEntity(m_dtm.getNodeName(node));
	}
	}
	break;
	default :
	}
	}
	} //TreeWalker

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