/*
    * Copyright (c) 2002-2025 Gargoyle Software Inc.
    *
    * 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
    * https://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.htmlunit.html.parser.neko;
  
  import static org.htmlunit.BrowserVersionFeatures.HTML_COMMAND_TAG;
  import static org.htmlunit.BrowserVersionFeatures.JS_SCRIPT_IN_TEMPLATE_EXECUTED_ON_ATTACH;
  
  import java.io.IOException;
  import java.io.StringReader;
  import java.net.URL;
  import java.nio.charset.Charset;
  import java.util.ArrayDeque;
  import java.util.Deque;
  
  import org.apache.commons.lang3.ArrayUtils;
  import org.htmlunit.BrowserVersion;
  import org.htmlunit.ObjectInstantiationException;
  import org.htmlunit.WebClient;
  import org.htmlunit.WebResponse;
  import org.htmlunit.cyberneko.HTMLConfiguration;
  import org.htmlunit.cyberneko.HTMLElements;
  import org.htmlunit.cyberneko.HTMLScanner;
  import org.htmlunit.cyberneko.HTMLTagBalancingListener;
  import org.htmlunit.cyberneko.xerces.parsers.AbstractSAXParser;
  import org.htmlunit.cyberneko.xerces.xni.Augmentations;
  import org.htmlunit.cyberneko.xerces.xni.QName;
  import org.htmlunit.cyberneko.xerces.xni.XMLAttributes;
  import org.htmlunit.cyberneko.xerces.xni.XMLString;
  import org.htmlunit.cyberneko.xerces.xni.XNIException;
  import org.htmlunit.cyberneko.xerces.xni.parser.XMLInputSource;
  import org.htmlunit.cyberneko.xerces.xni.parser.XMLParserConfiguration;
  import org.htmlunit.html.DomComment;
  import org.htmlunit.html.DomDocumentType;
  import org.htmlunit.html.DomElement;
  import org.htmlunit.html.DomNode;
  import org.htmlunit.html.DomText;
  import org.htmlunit.html.ElementFactory;
  import org.htmlunit.html.Html;
  import org.htmlunit.html.HtmlBody;
  import org.htmlunit.html.HtmlElement;
  import org.htmlunit.html.HtmlForm;
  import org.htmlunit.html.HtmlHiddenInput;
  import org.htmlunit.html.HtmlImage;
  import org.htmlunit.html.HtmlPage;
  import org.htmlunit.html.HtmlSvg;
  import org.htmlunit.html.HtmlTable;
  import org.htmlunit.html.HtmlTableRow;
  import org.htmlunit.html.HtmlTemplate;
  import org.htmlunit.html.ScriptElement;
  import org.htmlunit.html.SubmittableElement;
  import org.htmlunit.html.XHtmlPage;
  import org.htmlunit.html.parser.HTMLParser;
  import org.htmlunit.html.parser.HTMLParserDOMBuilder;
  import org.htmlunit.html.parser.HTMLParserListener;
  import org.htmlunit.javascript.host.html.HTMLBodyElement;
  import org.htmlunit.util.StringUtils;
  import org.w3c.dom.Node;
  import org.xml.sax.Attributes;
  import org.xml.sax.ContentHandler;
  import org.xml.sax.Locator;
  import org.xml.sax.SAXException;
  import org.xml.sax.ext.LexicalHandler;
  
  /**
   * <span style="color:red">INTERNAL API - SUBJECT TO CHANGE AT ANY TIME - USE AT YOUR OWN RISK.</span><br>
   *
   * The parser and DOM builder. This class subclasses Xerces's AbstractSAXParser and implements
   * the ContentHandler interface. Thus all parser APIs are kept private. The ContentHandler methods
   * consume SAX events to build the page DOM
   *
   * @author <a href="mailto:cse@dynabean.de">Christian Sell</a>
   * @author David K. Taylor
   * @author Chris Erskine
   * @author Ahmed Ashour
   * @author Marc Guillemot
   * @author Ethan Glasser-Camp
   * @author Sudhan Moghe
   * @author Ronald Brill
   * @author Frank Danek
   * @author Carsten Steul
   * @author Ronny Shapiro
   * @author Atsushi Nakagawa
   */
  final class HtmlUnitNekoDOMBuilder extends AbstractSAXParser
          implements ContentHandler, LexicalHandler, HTMLTagBalancingListener, HTMLParserDOMBuilder {
  
      // cache Neko Elements for performance and memory efficiency
     private static final HTMLElements HTMLELEMENTS;
     private static final HTMLElements HTMLELEMENTS_WITH_CMD;
 
     static {
         // continue short code enumeration
         final short commandShortCode = HTMLElements.UNKNOWN + 1;
 
         final HTMLElements.Element command = new HTMLElements.Element(commandShortCode, "COMMAND",
                 HTMLElements.Element.EMPTY, new short[] {HTMLElements.BODY, HTMLElements.HEAD}, null);
 
         HTMLELEMENTS = new HTMLElements();
 
         final HTMLElements value = new HTMLElements();
         value.setElement(command);
         HTMLELEMENTS_WITH_CMD = value;
     }
 
     private enum HeadParsed { YES, SYNTHESIZED, NO }
 
     private final HTMLParser htmlParser_;
     private final HtmlPage page_;
 
     private Locator locator_;
     private final Deque<DomNode> stack_ = new ArrayDeque<>();
 
     /** Did the snippet tried to overwrite the start node? */
     private boolean snippetStartNodeOverwritten_;
     private final int initialSize_;
     private DomNode currentNode_;
     private final boolean createdByJavascript_;
     private final XMLString characters_ = new XMLString();
     private HtmlUnitNekoDOMBuilder.HeadParsed headParsed_ = HeadParsed.NO;
     private HtmlElement body_;
     private boolean lastTagWasSynthesized_;
     private HtmlForm consumingForm_;
     private boolean formEndingIsAdjusting_;
     private boolean insideSvg_;
     private boolean insideTemplate_;
 
     private static final String FEATURE_AUGMENTATIONS = "http://cyberneko.org/html/features/augmentations";
     private static final String FEATURE_PARSE_NOSCRIPT
         = "http://cyberneko.org/html/features/parse-noscript-content";
 
     /**
      * Parses and then inserts the specified HTML content into the HTML content currently being parsed.
      * @param html the HTML content to push
      */
     @Override
     public void pushInputString(final String html) {
         page_.registerParsingStart();
         page_.registerInlineSnippetParsingStart();
         try {
             final WebResponse webResponse = page_.getWebResponse();
             final Charset charset = webResponse.getContentCharset();
             final String url = webResponse.getWebRequest().getUrl().toString();
             final XMLInputSource in = new XMLInputSource(null, url, null, new StringReader(html), charset.name());
             ((HTMLConfiguration) parserConfiguration_).evaluateInputSource(in);
         }
         finally {
             page_.registerParsingEnd();
             page_.registerInlineSnippetParsingEnd();
         }
     }
 
     /**
      * Creates a new builder for parsing the specified response contents.
      * @param node the location at which to insert the new content
      * @param url the page's URL
      * @param createdByJavascript if true the (script) tag was created by javascript
      */
     HtmlUnitNekoDOMBuilder(final HTMLParser htmlParser,
             final DomNode node, final URL url, final String htmlContent, final boolean createdByJavascript) {
         super(createConfiguration(node.getPage().getWebClient().getBrowserVersion()));
 
         htmlParser_ = htmlParser;
         page_ = (HtmlPage) node.getPage();
 
         currentNode_ = node;
         for (final Node ancestor : currentNode_.getAncestors()) {
             stack_.push((DomNode) ancestor);
         }
         createdByJavascript_ = createdByJavascript;
 
         final WebClient webClient = page_.getWebClient();
         final HTMLParserListener listener = webClient.getHTMLParserListener();
         final boolean reportErrors = listener != null;
         if (reportErrors) {
             parserConfiguration_.setErrorHandler(new HtmlUnitNekoHTMLErrorHandler(listener, url, htmlContent));
         }
 
         try {
             setFeature(FEATURE_AUGMENTATIONS, true);
             setFeature("http://cyberneko.org/html/features/report-errors", reportErrors);
             setFeature(FEATURE_PARSE_NOSCRIPT, !webClient.isJavaScriptEnabled());
             setFeature(HTMLScanner.ALLOW_SELFCLOSING_IFRAME, false);
 
             setContentHandler(this);
             setLexicalHandler(this); //comments and CDATA
         }
         catch (final SAXException e) {
             throw new ObjectInstantiationException("unable to create HTML parser", e);
         }
         initialSize_ = stack_.size();
     }
 
     /**
      * Create the configuration depending on the simulated browser
      * @return the configuration
      */
     private static XMLParserConfiguration createConfiguration(final BrowserVersion browserVersion) {
         if (browserVersion.hasFeature(HTML_COMMAND_TAG)) {
             return new HTMLConfiguration(HTMLELEMENTS_WITH_CMD);
         }
         return new HTMLConfiguration(HTMLELEMENTS);
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void setDocumentLocator(final Locator locator) {
         locator_ = locator;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void startDocument() throws SAXException {
         // nothing to do
     }
 
     /** {@inheritDoc} */
     @Override
     public void startElement(final QName element, final XMLAttributes attributes, final Augmentations augs)
         throws XNIException {
         // augs might change so we store only the interesting part
         lastTagWasSynthesized_ = augs.isSynthesized();
         super.startElement(element, attributes, augs);
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void startElement(String namespaceURI, final String localName, final String qName, final Attributes atts)
         throws SAXException {
 
         if (snippetStartNodeOverwritten_) {
             snippetStartNodeOverwritten_ = false;
             return;
         }
         handleCharacters();
 
         final String tagLower = StringUtils.toRootLowerCase(localName);
         if (page_.isParsingHtmlSnippet() && ("html".equals(tagLower) || "body".equals(tagLower))) {
             // we have to push the current node on the stack to make sure
             // the endElement call is able to remove a node from the stack
             stack_.push(currentNode_);
             return;
         }
 
         if ("head".equals(tagLower)) {
             if (headParsed_ == HeadParsed.YES || page_.isParsingHtmlSnippet()) {
                 // we have to push the current node on the stack to make sure
                 // the endElement call is able to remove a node from the stack
                 stack_.push(currentNode_);
                 return;
             }
 
             headParsed_ = lastTagWasSynthesized_ ? HeadParsed.SYNTHESIZED : HeadParsed.YES;
         }
 
         if (namespaceURI != null) {
             namespaceURI = namespaceURI.trim();
         }
 
         // If we're adding a body element, keep track of any temporary synthetic ones
         // that we may have had to create earlier (for document.write(), for example).
         HtmlBody oldBody = null;
         final boolean isBodyTag = "body".equals(tagLower);
         if (isBodyTag) {
             final HtmlBody body = page_.getBody();
             if (body != null) {
                 oldBody = body;
             }
         }
 
         // Add the new node.
         if (!(page_ instanceof XHtmlPage) && Html.XHTML_NAMESPACE.equals(namespaceURI)) {
             namespaceURI = null;
         }
 
         final ElementFactory factory =
                 htmlParser_.getElementFactory(page_, namespaceURI, qName, insideSvg_, false);
         if (factory == HtmlUnitNekoHtmlParser.SVG_FACTORY) {
             namespaceURI = Html.SVG_NAMESPACE;
         }
         final DomElement newElement = factory.createElementNS(page_, namespaceURI, qName, atts);
         newElement.setStartLocation(locator_.getLineNumber(), locator_.getColumnNumber());
 
         // parse can't replace everything as it does not buffer elements while parsing
         addNodeToRightParent(currentNode_, newElement);
 
         if (newElement instanceof HtmlSvg) {
             insideSvg_ = true;
         }
         else if (newElement instanceof HtmlTemplate) {
             insideTemplate_ = true;
         }
 
         // Forms own elements simply by enclosing source-wise rather than DOM parent-child relationship
         // Forms without a </form> will keep consuming forever
         if (newElement instanceof HtmlForm) {
             consumingForm_ = (HtmlForm) newElement;
             formEndingIsAdjusting_ = false;
         }
         else if (consumingForm_ != null) {
             // If the current form enclosed a suitable element
             if (newElement instanceof SubmittableElement) {
                 // Let these be owned by the form
                 if (((HtmlElement) newElement).getEnclosingForm() != consumingForm_) {
                     ((HtmlElement) newElement).setOwningForm(consumingForm_);
                 }
             }
         }
 
         // If we had an old synthetic body and we just added a real body element, quietly
         // remove the old body and move its children to the real body element we just added.
         if (oldBody != null) {
             oldBody.quietlyRemoveAndMoveChildrenTo(newElement);
         }
 
         if (!insideSvg_ && isBodyTag) {
             body_ = (HtmlElement) newElement;
         }
         else if (createdByJavascript_
                 && newElement instanceof ScriptElement
                 && (!insideTemplate_
                         || !page_.getWebClient().getBrowserVersion()
                                 .hasFeature(JS_SCRIPT_IN_TEMPLATE_EXECUTED_ON_ATTACH))) {
             final ScriptElement script = (ScriptElement) newElement;
             script.markAsCreatedByDomParser();
         }
 
         currentNode_ = newElement;
         stack_.push(currentNode_);
     }
 
     /**
      * Adds the new node to the right parent that is not necessary the currentNode in case of
      * malformed HTML code. The method tries to emulate the behavior of Firefox.
      */
     private void addNodeToRightParent(final DomNode currentNode, final DomElement newElement) {
         final String currentNodeName = currentNode.getNodeName();
         final String newNodeName = newElement.getNodeName();
 
         // First ensure table elements are housed correctly
         if (isTableChild(newNodeName)) {
             final DomNode parent =
                     "table".equals(currentNodeName) ? currentNode : findElementOnStack("table");
             appendChild(parent, newElement);
             return;
         }
         if ("tr".equals(newNodeName)) {
             final DomNode parent =
                     isTableChild(currentNodeName) ? currentNode : findElementOnStack("tbody", "thead", "tfoot");
             appendChild(parent, newElement);
             return;
         }
         if (isTableCell(newNodeName)) {
             final DomNode parent =
                     "tr".equals(currentNodeName) ? currentNode : findElementOnStack("tr");
             appendChild(parent, newElement);
             return;
         }
 
         // Next ensure non-table elements don't appear in tables
         if ("table".equals(currentNodeName) || isTableChild(currentNodeName) || "tr".equals(currentNodeName)) {
             if ("template".equals(newNodeName)) {
                 currentNode.appendChild(newElement);
             }
 
             // Scripts, forms, and styles are exempt
             else if (!"colgroup".equals(currentNodeName)
                     && ("script".equals(newNodeName)
                         || "form".equals(newNodeName)
                         || "style".equals(newNodeName))) {
                 currentNode.appendChild(newElement);
             }
 
             // These are good
             else if ("col".equals(newNodeName) && "colgroup".equals(currentNodeName)) {
                 currentNode.appendChild(newElement);
             }
             else if ("caption".equals(currentNodeName)) {
                 currentNode.appendChild(newElement);
             }
             else if (newElement instanceof HtmlHiddenInput) {
                 currentNode.appendChild(newElement);
             }
             else {
                 // Move before the table
                 final DomNode parent = findElementOnStack("table");
                 parent.insertBefore(newElement);
             }
             return;
         }
 
         if (formEndingIsAdjusting_ && "form".equals(currentNodeName)) {
             // We cater to HTMLTagBalancer's shortcomings by moving this node out of the <form>
             appendChild(currentNode.getParentNode(), newElement);
             return;
         }
 
         // Everything else
         appendChild(currentNode, newElement);
     }
 
     private DomNode findElementOnStack(final String... searchedElementNames) {
         DomNode searchedNode = null;
         for (final DomNode node : stack_) {
             if (ArrayUtils.contains(searchedElementNames, node.getNodeName())) {
                 searchedNode = node;
                 break;
             }
         }
 
         if (searchedNode == null) {
             searchedNode = stack_.peek(); // this is surely wrong but at least it won't throw a NPE
         }
 
         return searchedNode;
     }
 
     private static boolean isTableChild(final String nodeName) {
         if (nodeName == null || nodeName.length() < 5) {
             return false;
         }
 
         return "thead".equals(nodeName)
                 || "tbody".equals(nodeName)
                 || "tfoot".equals(nodeName)
                 || "caption".equals(nodeName)
                 || "colgroup".equals(nodeName);
     }
 
     private static boolean isTableCell(final String nodeName) {
         if (nodeName == null || nodeName.length() != 2) {
             return false;
         }
         return "td".equals(nodeName) || "th".equals(nodeName);
     }
 
     /** {@inheritDoc} */
     @Override
     public void endElement(final QName element, final Augmentations augs)
         throws XNIException {
         // augs might change so we store only the interesting part
         lastTagWasSynthesized_ = augs.isSynthesized();
         super.endElement(element, augs);
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void endElement(final String namespaceURI, final String localName, final String qName)
         throws SAXException {
 
         final String tagLower = StringUtils.toRootLowerCase(localName);
 
         handleCharacters();
 
         if (page_.isParsingHtmlSnippet()) {
             if ("html".equals(tagLower) || "body".equals(tagLower)) {
                 return;
             }
             if (stack_.size() == initialSize_) {
                 // a <p> inside a <p> is valid for innerHTML processing
                 // see HTMLParser2Test for more cases
                 snippetStartNodeOverwritten_ = !StringUtils.equalsChar('p', tagLower);
                 return;
             }
         }
 
         if ("svg".equals(tagLower)) {
             insideSvg_ = false;
         }
         else if ("template".equals(tagLower)) {
             insideTemplate_ = false;
         }
 
         // this only avoids a problem when the stack is empty here
         // but for this case we made the problem before - the balancing
         // is broken already
         if (stack_.isEmpty()) {
             return;
         }
 
         final DomNode previousNode = stack_.pop(); //remove currentElement from stack
         previousNode.setEndLocation(locator_.getLineNumber(), locator_.getColumnNumber());
 
         if ("form".equals(tagLower) && !lastTagWasSynthesized_) {
             // We get here if the </form> was on the same DOM tree depth as the <form> that started it,
             // otherwise HTMLTagBalancer gives us the end through ignoredEndElement()
             consumingForm_ = null;
         }
 
         if (!stack_.isEmpty()) {
             currentNode_ = stack_.peek();
         }
 
         final boolean postponed = page_.isParsingInlineHtmlSnippet();
         previousNode.onAllChildrenAddedToPage(postponed);
     }
 
     /** {@inheritDoc} */
     @Override
     public void characters(final char[] ch, final int start, final int length) throws SAXException {
         characters_.append(ch, start, length);
     }
 
     /** {@inheritDoc} */
     @Override
     public void ignorableWhitespace(final char[] ch, final int start, final int length) throws SAXException {
         characters_.append(ch, start, length);
     }
 
     /**
      * Picks up the character data accumulated so far and add it to the current element as a text node.
      */
     private void handleCharacters() {
         // make the code easier to read because we remove a nesting level
         if (characters_.length() == 0) {
             return;
         }
 
         // Use the normal behavior: append a text node for the accumulated text.
         final String textValue = characters_.toString();
         characters_.clear();
 
         if (org.apache.commons.lang3.StringUtils.isBlank(textValue)) {
             appendChild(currentNode_, new DomText(page_, textValue));
         }
         else {
             // malformed HTML: </td>some text</tr> => text comes before the table
             if (currentNode_ instanceof HtmlTableRow) {
                 final HtmlTableRow row = (HtmlTableRow) currentNode_;
                 final HtmlTable enclosingTable = row.getEnclosingTable();
                 if (enclosingTable != null) { // may be null when called from Range.createContextualFragment
                     if (enclosingTable.getPreviousSibling() instanceof DomText) {
                         final DomText domText = (DomText) enclosingTable.getPreviousSibling();
                         domText.setTextContent(domText.getWholeText() + textValue);
                     }
                     else {
                         enclosingTable.insertBefore(new DomText(page_, textValue));
                     }
                 }
             }
             else if (currentNode_ instanceof HtmlTable) {
                 final HtmlTable enclosingTable = (HtmlTable) currentNode_;
                 if (enclosingTable.getPreviousSibling() instanceof DomText) {
                     final DomText domText = (DomText) enclosingTable.getPreviousSibling();
                     domText.setTextContent(domText.getWholeText() + textValue);
                 }
                 else {
                     enclosingTable.insertBefore(new DomText(page_, textValue));
                 }
             }
             else if (currentNode_ instanceof HtmlImage) {
                 currentNode_.getParentNode().appendChild(new DomText(page_, textValue));
             }
             else {
                 appendChild(currentNode_, new DomText(page_, textValue));
             }
         }
     }
 
     /** {@inheritDoc} */
     @Override
     public void endDocument() throws SAXException {
         handleCharacters();
         if (locator_ != null) {
             page_.setEndLocation(locator_.getLineNumber(), locator_.getColumnNumber());
         }
     }
 
     /** {@inheritDoc} */
     @Override
     public void startPrefixMapping(final String prefix, final String uri) throws SAXException {
         // nothing to do
     }
 
     /** {@inheritDoc} */
     @Override
     public void endPrefixMapping(final String prefix) throws SAXException {
         // nothing to do
     }
 
     /** {@inheritDoc} */
     @Override
     public void processingInstruction(final String target, final String data) throws SAXException {
         // nothing to do
     }
 
     /** {@inheritDoc} */
     @Override
     public void skippedEntity(final String name) throws SAXException {
         // nothing to do
     }
 
     // LexicalHandler methods
 
     /** {@inheritDoc} */
     @Override
     public void comment(final char[] ch, final int start, final int length) {
         handleCharacters();
         final String data = new String(ch, start, length);
         final DomComment comment = new DomComment(page_, data);
         appendChild(currentNode_, comment);
     }
 
     /** {@inheritDoc} */
     @Override
     public void endCDATA() {
         // nothing to do
     }
 
     /** {@inheritDoc} */
     @Override
     public void endDTD() {
         // nothing to do
     }
 
     /** {@inheritDoc} */
     @Override
     public void endEntity(final String name) {
         // nothing to do
     }
 
     /** {@inheritDoc} */
     @Override
     public void startCDATA() {
         // nothing to do
     }
 
     /** {@inheritDoc} */
     @Override
     public void startDTD(final String name, final String publicId, final String systemId) {
         final DomDocumentType type = new DomDocumentType(page_, name, publicId, systemId);
         page_.setDocumentType(type);
 
         final Node child;
         child = type;
         page_.appendChild(child);
     }
 
     /** {@inheritDoc} */
     @Override
     public void startEntity(final String name) {
         // nothing to do
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void ignoredEndElement(final QName element, final Augmentations augs) {
         // HTMLTagBalancer brings us here if </form> was found in the source on a different
         // DOM tree depth (either above or below) to the <form> that started it
         if ("form".equals(element.getLocalpart()) && consumingForm_ != null) {
             consumingForm_ = null;
 
             if (findElementOnStack("table", "form") instanceof HtmlTable) {
                 // The </form> just goes missing for these (really? just tables?)
             }
             else {
                 /*
                  * This </form> was ignored by HTMLTagBalancer as it generates its own
                  * </form> at the end of the depth with the starting <form>.
                  * e.g. This:
                  * | <form>
                  * |   <div>
                  * |     </form> <!--ignored by HTMLTagBalancer-->
                  * |   </div>
                  * |   <input>
                  *
                  * is turned into:
                  * | <form>
                  * |   <div>
                  * |   </div>
                  * |   <input>
                  * | </form> <!--synthesized by HTMLTagBalancer-->
                  *
                  * but this isn't suitable for us because </form> shouldn't be ignored but
                  * rather moved directly behind the tree it's in to instead become:
                  * | <form>
                  * |   <div>
                  * |   </div>
                  * | </form> <!--moved out of div-->
                  * | <input> <!--proceeding children are not part of form-->
                  */
                 // We cater for this by moving out nodes such as the <input> in the above
                 // diagram out of the form
                 formEndingIsAdjusting_ = true;
             }
         }
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void ignoredStartElement(final QName elem, final XMLAttributes attrs, final Augmentations augs) {
         // when multiple html/body elements are encountered, the attributes of the discarded
         // elements are used when not previously defined
         if (attrs != null && body_ != null) {
             final String lp = elem.getLocalpart();
             if (lp != null && lp.length() == 4) {
                 if ("body".equalsIgnoreCase(lp)) {
                     copyAttributes(body_, attrs);
                 }
                 else if ("html".equalsIgnoreCase(lp)) {
                     final DomNode parent = body_.getParentNode();
                     if (parent instanceof DomElement) {
                         copyAttributes((DomElement) parent, attrs);
                     }
                 }
             }
         }
     }
 
     private static void copyAttributes(final DomElement to, final XMLAttributes attrs) {
         final int length = attrs.getLength();
 
         for (int i = 0; i < length; i++) {
             final String attrName = StringUtils.toRootLowerCase(attrs.getLocalName(i));
             if (to.getAttributes().getNamedItem(attrName) == null) {
                 to.setAttribute(attrName, attrs.getValue(i));
                 if (attrName.startsWith("on") && to.getPage().getWebClient().isJavaScriptEngineEnabled()
                         && to.getScriptableObject() instanceof HTMLBodyElement) {
                     final HTMLBodyElement jsBody = to.getScriptableObject();
                     jsBody.createEventHandlerFromAttribute(attrName, attrs.getValue(i));
                 }
             }
         }
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void parse(final XMLInputSource inputSource) throws XNIException, IOException {
         final HTMLParserDOMBuilder oldBuilder = page_.getDOMBuilder();
         page_.setDOMBuilder(this);
         try {
             super.parse(inputSource);
         }
         finally {
             page_.setDOMBuilder(oldBuilder);
         }
     }
 
     private static void appendChild(final DomNode parent, final DomNode child) {
         if (parent instanceof HtmlTemplate) {
             ((HtmlTemplate) parent).getContent().appendChild(child);
             return;
         }
 
         parent.appendChild(child);
     }
 }