/*

 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/*

 * Copyright 1999-2004 The Apache Software Foundation.

 *

 * 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: TreeWalker.java,v 1.2.4.1 2005/09/15 08:15:59 suresh_emailid Exp $

 */

package com.sun.org.apache.xml.internal.utils;

import java.io.File;

import org.w3c.dom.Comment;

import org.w3c.dom.Element;

import org.w3c.dom.EntityReference;

import org.w3c.dom.NamedNodeMap;

import org.w3c.dom.Node;

import org.w3c.dom.ProcessingInstruction;

import org.w3c.dom.Text;

import org.xml.sax.ContentHandler;

import org.xml.sax.Locator;

import org.xml.sax.ext.LexicalHandler;

import org.xml.sax.helpers.LocatorImpl;

/**

 * This class does a pre-order walk of the DOM tree, calling a ContentHandler

 * interface as it goes.

 * @xsl.usage advanced

 */

public class TreeWalker

{

  /** Local reference to a ContentHandler          */

  private ContentHandler m_contentHandler = null;

  // ARGHH!!  JAXP Uses Xerces without setting the namespace processing to ON!

  // DOM2Helper m_dh = new DOM2Helper();

  /** DomHelper for this TreeWalker          */

  protected DOMHelper m_dh;

        /** Locator object for this TreeWalker          */

        private LocatorImpl m_locator = new LocatorImpl();

  /**

   * Get the ContentHandler used for the tree walk.

   *

   * @return the ContentHandler used for the tree walk

   */

  public ContentHandler getContentHandler()

  {

    return m_contentHandler;

  }

  /**

   * Get the ContentHandler used for the tree walk.

   *

   * @return the ContentHandler used for the tree walk

   */

  public void setContentHandler(ContentHandler ch)

  {

    m_contentHandler = ch;

  }

        /**

   * Constructor.

   * @param   contentHandler The implemention of the

   * @param   systemId System identifier for the document.

   * contentHandler operation (toXMLString, digest, ...)

   */

  public TreeWalker(ContentHandler contentHandler, DOMHelper dh, String systemId)

  {

    this.m_contentHandler = contentHandler;

    m_contentHandler.setDocumentLocator(m_locator);

    if (systemId != null)

        m_locator.setSystemId(systemId);

    else {

        try {

          // Bug see Bugzilla  26741

         }

         catch (SecurityException se) {// user.dir not accessible from applet

         }

    }

    m_dh = dh;

  }

  /**

   * Constructor.

   * @param   contentHandler The implemention of the

   * contentHandler operation (toXMLString, digest, ...)

   */

  public TreeWalker(ContentHandler contentHandler, DOMHelper dh)

  {

    this.m_contentHandler = contentHandler;

    m_contentHandler.setDocumentLocator(m_locator);

    try {

       // Bug see Bugzilla  26741

    }

    catch (SecurityException se){// user.dir not accessible from applet

    }

    m_dh = dh;

  }

  /**

   * Constructor.

   * @param   contentHandler The implemention of the

   * contentHandler operation (toXMLString, digest, ...)

   */

  public TreeWalker(ContentHandler contentHandler)

  {

    this.m_contentHandler = contentHandler;

                if (m_contentHandler != null)

                        m_contentHandler.setDocumentLocator(m_locator);

                try {

                   // Bug see Bugzilla  26741

                }

                catch (SecurityException se){// user.dir not accessible from applet

    }

    m_dh = new DOM2Helper();

  }

  /**

   * Perform a pre-order traversal non-recursive style.

   *

   * Note that TreeWalker assumes that the subtree is intended to represent

   * a complete (though not necessarily well-formed) document and, during a

   * traversal, startDocument and endDocument will always be issued to the

   * SAX listener.

   *

   * @param pos Node in the tree where to start traversal

   *

   * @throws TransformerException

   */

  public void traverse(Node pos) throws org.xml.sax.SAXException

  {

        this.m_contentHandler.startDocument();

        traverseFragment(pos);

        this.m_contentHandler.endDocument();

  }

  /**

   * Perform a pre-order traversal non-recursive style.

   *

   * In contrast to the traverse() method this method will not issue

   * startDocument() and endDocument() events to the SAX listener.

   *

   * @param pos Node in the tree where to start traversal

   *

   * @throws TransformerException

   */

  public void traverseFragment(Node pos) throws org.xml.sax.SAXException

  {

    Node top = pos;

    while (null != pos)

    {

      startNode(pos);

      Node nextNode = pos.getFirstChild();

      while (null == nextNode)

      {

        endNode(pos);

        if (top.equals(pos))

          break;

        nextNode = pos.getNextSibling();

        if (null == nextNode)

        {

          pos = pos.getParentNode();

          if ((null == pos) || (top.equals(pos)))

          {

            if (null != pos)

              endNode(pos);

            nextNode = null;

            break;

          }

        }

      }

      pos = nextNode;

    }

  }

  /**

   * Perform a pre-order traversal non-recursive style.

   * Note that TreeWalker assumes that the subtree is intended to represent

   * a complete (though not necessarily well-formed) document and, during a

   * traversal, startDocument and endDocument will always be issued to the

   * SAX listener.

   *

   * @param pos Node in the tree where to start traversal

   * @param top Node in the tree where to end traversal

   *

   * @throws TransformerException

   */

  public void traverse(Node pos, Node top) throws org.xml.sax.SAXException

  {

        this.m_contentHandler.startDocument();

    while (null != pos)

    {

      startNode(pos);

      Node nextNode = pos.getFirstChild();

      while (null == nextNode)

      {

        endNode(pos);

        if ((null != top) && top.equals(pos))

          break;

        nextNode = pos.getNextSibling();

        if (null == nextNode)

        {

          pos = pos.getParentNode();

          if ((null == pos) || ((null != top) && top.equals(pos)))

          {

            nextNode = null;

            break;

          }

        }

      }

      pos = nextNode;

    }

    this.m_contentHandler.endDocument();

  }

  /** Flag indicating whether following text to be processed is raw text          */

  boolean nextIsRaw = false;

  /**

   * Optimized dispatch of characters.

   */

  private final void dispatachChars(Node node)

     throws org.xml.sax.SAXException

  {

    if(m_contentHandler instanceof com.sun.org.apache.xml.internal.dtm.ref.dom2dtm.DOM2DTM.CharacterNodeHandler)

    {

      ((com.sun.org.apache.xml.internal.dtm.ref.dom2dtm.DOM2DTM.CharacterNodeHandler)m_contentHandler).characters(node);

    }

    else

    {

      String data = ((Text) node).getData();

      this.m_contentHandler.characters(data.toCharArray(), 0, data.length());

    }

  }

  /**

   * Start processing given node

   *

   *

   * @param node Node to process

   *

   * @throws org.xml.sax.SAXException

   */

  protected void startNode(Node node) throws org.xml.sax.SAXException

  {

    if (m_contentHandler instanceof NodeConsumer)

    {

      ((NodeConsumer) m_contentHandler).setOriginatingNode(node);

    }

                if (node instanceof Locator)

                {

                        Locator loc = (Locator)node;

                        m_locator.setColumnNumber(loc.getColumnNumber());

                        m_locator.setLineNumber(loc.getLineNumber());

                        m_locator.setPublicId(loc.getPublicId());

                        m_locator.setSystemId(loc.getSystemId());

                }

                else

                {

                        m_locator.setColumnNumber(0);

      m_locator.setLineNumber(0);

                }

    switch (node.getNodeType())

    {

    case Node.COMMENT_NODE :

    {

      String data = ((Comment) node).getData();

      if (m_contentHandler instanceof LexicalHandler)

      {

        LexicalHandler lh = ((LexicalHandler) this.m_contentHandler);

        lh.comment(data.toCharArray(), 0, data.length());

      }

    }

    break;

    case Node.DOCUMENT_FRAGMENT_NODE :

      // ??;

      break;

    case Node.DOCUMENT_NODE :

      break;

    case Node.ELEMENT_NODE :

      NamedNodeMap atts = ((Element) node).getAttributes();

      int nAttrs = atts.getLength();

      // System.out.println("TreeWalker#startNode: "+node.getNodeName());

      for (int i = 0; i < nAttrs; i++)

      {

        Node attr = atts.item(i);

        String attrName = attr.getNodeName();

        // System.out.println("TreeWalker#startNode: attr["+i+"] = "+attrName+", "+attr.getNodeValue());

        if (attrName.equals("xmlns") || attrName.startsWith("xmlns:"))

        {

          // System.out.println("TreeWalker#startNode: attr["+i+"] = "+attrName+", "+attr.getNodeValue());

          int index;

          // Use "" instead of null, as Xerces likes "" for the

          // name of the default namespace.  Fix attributed

          // to "Steven Murray" <smurray@ebt.com>.

          String prefix = (index = attrName.indexOf(":")) < 0

                          ? "" : attrName.substring(index + 1);

          this.m_contentHandler.startPrefixMapping(prefix,

                                                   attr.getNodeValue());

        }

      }

      // System.out.println("m_dh.getNamespaceOfNode(node): "+m_dh.getNamespaceOfNode(node));

      // System.out.println("m_dh.getLocalNameOfNode(node): "+m_dh.getLocalNameOfNode(node));

      String ns = m_dh.getNamespaceOfNode(node);

      if(null == ns)

        ns = "";

      this.m_contentHandler.startElement(ns,

                                         m_dh.getLocalNameOfNode(node),

                                         node.getNodeName(),

                                         new AttList(atts, m_dh));

      break;

    case Node.PROCESSING_INSTRUCTION_NODE :

    {

      ProcessingInstruction pi = (ProcessingInstruction) node;

      String name = pi.getNodeName();

      // String data = pi.getData();

      if (name.equals("xslt-next-is-raw"))

      {

        nextIsRaw = true;

      }

      else

      {

        this.m_contentHandler.processingInstruction(pi.getNodeName(),

                                                    pi.getData());

      }

    }

    break;

    case Node.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 Node.TEXT_NODE :

    {

      //String data = ((Text) node).getData();

      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 Node.ENTITY_REFERENCE_NODE :

    {

      EntityReference eref = (EntityReference) node;

      if (m_contentHandler instanceof LexicalHandler)

      {

        ((LexicalHandler) this.m_contentHandler).startEntity(

          eref.getNodeName());

      }

      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(Node node) throws org.xml.sax.SAXException

  {

    switch (node.getNodeType())

    {

    case Node.DOCUMENT_NODE :

      break;

    case Node.ELEMENT_NODE :

      String ns = m_dh.getNamespaceOfNode(node);

      if(null == ns)

        ns = "";

      this.m_contentHandler.endElement(ns,

                                         m_dh.getLocalNameOfNode(node),

                                         node.getNodeName());

      NamedNodeMap atts = ((Element) node).getAttributes();

      int nAttrs = atts.getLength();

      for (int i = 0; i < nAttrs; i++)

      {

        Node attr = atts.item(i);

        String attrName = attr.getNodeName();

        if (attrName.equals("xmlns") || attrName.startsWith("xmlns:"))

        {

          int index;

          // Use "" instead of null, as Xerces likes "" for the

          // name of the default namespace.  Fix attributed

          // to "Steven Murray" <smurray@ebt.com>.

          String prefix = (index = attrName.indexOf(":")) < 0

                          ? "" : attrName.substring(index + 1);

          this.m_contentHandler.endPrefixMapping(prefix);

        }

      }

      break;

    case Node.CDATA_SECTION_NODE :

      break;

    case Node.ENTITY_REFERENCE_NODE :

    {

      EntityReference eref = (EntityReference) node;

      if (m_contentHandler instanceof LexicalHandler)

      {

        LexicalHandler lh = ((LexicalHandler) this.m_contentHandler);

        lh.endEntity(eref.getNodeName());

      }

    }

    break;

    default :

    }

  }

}  //TreeWalker