Document/src/document/wiki/visitor/docbook.php - zetacomponents - Git at Google

 <?php
 /**
  * File containing the ezcDocumentWikiDocbookVisitor class
  *
  * 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 Document
  * @version //autogen//
  * @copyright Copyright (C) 2005-2010 eZ Systems AS. All rights reserved.
  * @license http://www.apache.org/licenses/LICENSE-2.0 Apache License, Version 2.0
  */

 /**
  * Docbook visitor for the Wiki AST.
  *
  * @package Document
  * @version //autogen//
  */
 class ezcDocumentWikiDocbookVisitor extends ezcDocumentWikiVisitor
 {
     /**
      * Mapping of class names to internal visitors for the respective nodes.
      *
      * @var array
      */
     protected $complexVisitMapping = array(
         'ezcDocumentWikiTextNode'           => 'visitText',
         'ezcDocumentWikiSeparatorNode'      => 'visitText',
         'ezcDocumentWikiBoldNode'           => 'visitEmphasisMarkup',
         'ezcDocumentWikiItalicNode'         => 'visitEmphasisMarkup',
         'ezcDocumentWikiUnderlineNode'      => 'visitEmphasisMarkup',
         'ezcDocumentWikiTitleNode'          => 'visitTitle',
         'ezcDocumentWikiLinkNode'           => 'visitLink',
         'ezcDocumentWikiExternalLinkNode'   => 'visitExternalLink',
         'ezcDocumentWikiInternalLinkNode'   => 'visitExternalLink',
         'ezcDocumentWikiInterWikiLinkNode'  => 'visitExternalLink',
         'ezcDocumentWikiBulletListNode'     => 'visitList',
         'ezcDocumentWikiEnumeratedListNode' => 'visitList',
         'ezcDocumentWikiImageNode'          => 'visitImages',
         'ezcDocumentWikiLiteralBlockNode'   => 'visitLiteralBlock',
         'ezcDocumentWikiInlineLiteralNode'  => 'visitLiteral',
         'ezcDocumentWikiTableRowNode'       => 'visitTableRow',
         'ezcDocumentWikiTableCellNode'      => 'visitTableCell',
         'ezcDocumentWikiLineBreakNode'      => 'visitLineBreak',
         'ezcDocumentWikiParagraphNode'      => 'visitParagraph',
         'ezcDocumentWikiBlockquoteNode'     => 'visitBlockquote',
         'ezcDocumentWikiFootnoteNode'       => 'visitFootnote',
         'ezcDocumentWikiPluginNode'         => 'visitPlugin',

         // Node markup is ignored, because there is no equivalent in docbook
         'ezcDocumentWikiDeletedNode'   => 'visitChildren',
     );

     /**
      * Direct mapping of AST node class names to docbook element names.
      *
      * @var array
      */
     protected $simpleVisitMapping = array(
         'ezcDocumentWikiSectionNode'            => 'section',
         'ezcDocumentWikiInlineQuoteNode'        => 'quote',
         'ezcDocumentWikiSuperscriptNode'        => 'superscript',
         'ezcDocumentWikiSubscriptNode'          => 'subscript',
         'ezcDocumentWikiMonospaceNode'          => 'literal',
         'ezcDocumentWikiBulletListItemNode'     => 'listitem',
         'ezcDocumentWikiEnumeratedListItemNode' => 'listitem',
         'ezcDocumentWikiPageBreakNode'          => 'beginpage',

         'ezcDocumentWikiTableNode'              => 'table',
     );

     /**
      * Array with nodes, which can be ignored during the transformation
      * process, they only provide additional information during preprocessing.
      *
      * @var array
      */
     protected $skipNodes = array();

     /**
      * DOM document
      *
      * @var DOMDocument
      */
     protected $document;

     /**
      * Docarate Wiki AST
      *
      * Visit the Wiki abstract syntax tree.
      *
      * @param ezcDocumentWikiDocumentNode $ast
      * @return mixed
      */
     public function visit( ezcDocumentWikiDocumentNode $ast )
     {
         parent::visit( $ast );

         // Create article from AST
         $imp = new DOMImplementation();
         $dtd = $imp->createDocumentType( 'article', '-//OASIS//DTD DocBook XML V4.5//EN', 'http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd' );
         $this->document = $imp->createDocument( 'http://docbook.org/ns/docbook', '', $dtd );
         $this->document->formatOutput = true;

 //        $root = $this->document->createElement( 'article' );
         $root = $this->document->createElementNs( 'http://docbook.org/ns/docbook', 'article' );
         $this->document->appendChild( $root );

         // Visit all childs of the AST root node.
         foreach ( $ast->nodes as $node )
         {
             $this->visitNode( $root, $node );
         }

         return $this->document;
     }

     /**
      * Visit single AST node
      *
      * Visit a single AST node, may be called for each node found anywhere
      * as child. The current position in the DOMDocument is passed by a
      * reference to the current DOMNode, which is operated on.
      *
      * @param DOMNode $root
      * @param ezcDocumentWikiNode $node
      * @return void
      */
     protected function visitNode( DOMNode $root, ezcDocumentWikiNode $node )
     {
         // Iterate over available visitors and use them to visit the nodes.
         foreach ( $this->complexVisitMapping as $class => $method )
         {
             if ( $node instanceof $class )
             {
                 return $this->$method( $root, $node );
             }
         }

         // Check if we have a simple class to element name mapping
         foreach ( $this->simpleVisitMapping as $class => $elementName )
         {
             if ( $node instanceof $class )
             {
                 $element = $this->document->createElement( $elementName );
                 $root->appendChild( $element );

                 foreach ( $node->nodes as $child )
                 {
                     $this->visitNode( $element, $child );
                 }

                 return;
             }
         }

         // Check if you should just ignore the node for rendering
         foreach ( $this->skipNodes as $class )
         {
             if ( $node instanceof $class )
             {
                 return;
             }
         }

         // We could not find any valid visitor.
         throw new ezcDocumentMissingVisitorException( get_class( $node ), $node->token->line, $node->token->position );
     }

     /**
      * Visit emphasis markup
      *
      * @param DOMNode $root
      * @param ezcDocumentWikiNode $node
      * @return void
      */
     protected function visitEmphasisMarkup( DOMNode $root, ezcDocumentWikiNode $node )
     {
         $markup = $this->document->createElement( 'emphasis' );

         if ( $node instanceof ezcDocumentWikiBoldNode )
         {
             $markup->setAttribute( 'Role', 'strong' );
         }
         $root->appendChild( $markup );

         foreach ( $node->nodes as $child )
         {
             $this->visitNode( $markup, $child );
         }
     }

     /**
      * Visit section titles
      *
      * @param DOMNode $root
      * @param ezcDocumentWikiNode $node
      * @return void
      */
     protected function visitTitle( DOMNode $root, ezcDocumentWikiNode $node )
     {
         $title = $this->document->createElement( 'title' );
         $root->appendChild( $title );

         foreach ( $node->nodes as $child )
         {
             $this->visitNode( $title, $child );
         }
     }

     /**
      * Visit external link node
      *
      * @param DOMNode $root
      * @param ezcDocumentWikiNode $node
      * @return void
      */
     protected function visitExternalLink( DOMNode $root, ezcDocumentWikiNode $node )
     {
         $link = $this->document->createElement( 'ulink' );
         $link->setAttribute( 'url', $node->token->content );
         $link->appendChild( new DOMText( $node->token->content ) );
         $root->appendChild( $link );
     }

     /**
      * Visit link node
      *
      * Docbook has no support for description of links, so that the description
      * elements in the AST are omitted.
      *
      * @param DOMNode $root
      * @param ezcDocumentWikiNode $node
      * @return void
      */
     protected function visitLink( DOMNode $root, ezcDocumentWikiNode $node )
     {
         $link = $this->document->createElement( 'ulink' );
         $link->setAttribute( 'url', $linkUrl = $this->nodeListToString( $node->link ) );
         $root->appendChild( $link );

         if ( $node->nodes === array() )
         {
             $link->appendChild( new DOMText( $linkUrl ) );
         }
         else
         {
             foreach ( $node->nodes as $child )
             {
                 $this->visitNode( $link, $child );
             }
         }
     }

     /**
      * Visit list
      *
      * Ensure stacked lists are created inside another list item.
      *
      * @param DOMNode $root
      * @param ezcDocumentWikiNode $node
      * @return void
      */
     protected function visitList( DOMNode $root, ezcDocumentWikiNode $node )
     {
         if ( ( $root->tagName === 'itemizedlist' ) ||
              ( $root->tagName === 'orderedlist' ) )
         {
             $listitem = $this->document->createElement( 'listitem' );
             $root->appendChild( $listitem );
             $root = $listitem;
         }

         $list = $this->document->createElement(
             $node instanceof ezcDocumentWikiBulletListNode ? 'itemizedlist' : 'orderedlist'
         );
         $root->appendChild( $list );

         foreach ( $node->nodes as $child )
         {
             $this->visitNode( $list, $child );
         }
     }

     /**
      * Is inline node?
      *
      * Check if contents of the current node are a inline node
      *
      * @param DOMNode $node
      * @return bool
      */
     protected function isInlineNode( DOMNode $node )
     {
         return in_array( $node->tagName, array(
             'para',
             'acronym',
             'anchor',
             'author',
             'citation',
             'email',
             'emphasis',
             'footnote',
             'footnoteref',
             'inlinemediaobject',
             'literal',
             'quote',
             'subscript',
             'superscript',
             'link',
             'ulink',
         ) );
     }

     /**
      * Visit images
      *
      * @param DOMNode $root
      * @param ezcDocumentWikiNode $node
      * @return void
      */
     protected function visitImages( DOMNode $root, ezcDocumentWikiNode $node )
     {
         $media = $this->document->createElement( $this->isInlineNode( $root ) ? 'inlinemediaobject' : 'mediaobject' );
         $root->appendChild( $media );

         $imageObject = $this->document->createElement( 'imageobject' );
         $media->appendChild( $imageObject );

         $image = $this->document->createElement( 'imagedata' );
         $image->setAttribute( 'fileref', $this->nodeListToString( $node->resource ) );
         $imageObject->appendChild( $image );

         // Handle optional settings on images
         if ( $node->title !== array() )
         {
             $text = $this->document->createElement( 'textobject' );
             $media->appendChild( $text );
             foreach ( $node->title as $child )
             {
                 $this->visitNode( $text, $child );
             }
         }

         if ( $node->width )
         {
             $image->setAttribute( 'width', (int) $node->width );
         }

         if ( $node->height )
         {
             $image->setAttribute( 'depth', (int) $node->height );
         }

         if ( $node->alignement )
         {
             $image->setAttribute( 'align', $node->alignement );
         }

         foreach ( $node->nodes as $child )
         {
             $this->visitNode( $list, $child );
         }
     }

     /**
      * Visit literal block
      *
      * @param DOMNode $root
      * @param ezcDocumentWikiNode $node
      * @return void
      */
     protected function visitLiteralBlock( DOMNode $root, ezcDocumentWikiNode $node )
     {
         $literal = $this->document->createElement( 'literallayout', htmlspecialchars( $node->token->content ) );
         $root->appendChild( $literal );
     }

     /**
      * Visit literal
      *
      * @param DOMNode $root
      * @param ezcDocumentWikiNode $node
      * @return void
      */
     protected function visitLiteral( DOMNode $root, ezcDocumentWikiNode $node )
     {
         $literal = $this->document->createElement( 'literal', htmlspecialchars( $node->token->content ) );
         $root->appendChild( $literal );
     }

     /**
      * Visit table row
      *
      * Visit a table row and decide if it belongs into a tbody or a thead
      * section.
      *
      * @param DOMNode $root
      * @param ezcDocumentWikiNode $node
      * @return void
      */
     protected function visitTableRow( DOMNode $root, ezcDocumentWikiNode $node )
     {
         $header = true;
         foreach ( $node->nodes as $cell )
         {
             $header = $header && $cell->header;
         }

         // Get last child element in table
         if ( !( $last = $root->lastChild ) ||
              ( $last->nodeType !== XML_ELEMENT_NODE ) )
         {
             $last = false;
         }

         $type = $header ? 'thead' : 'tbody';
         if ( ( $last === false ) ||
              ( $last->tagName !== $type ) )
         {
             $wrapper = $this->document->createElement( $type );
             $root->appendChild( $wrapper );
             $root = $wrapper;
         }
         else
         {
             $root = $last;
         }

         $row = $this->document->createElement( 'row' );
         $root->appendChild( $row );

         foreach ( $node->nodes as $child )
         {
             $this->visitNode( $row, $child );
         }
     }


     /**
      * Visit table cell
      *
      * Visit a table cell and additionally always create an inner paragraph.
      *
      * @param DOMNode $root
      * @param ezcDocumentWikiNode $node
      * @return void
      */
     protected function visitTableCell( DOMNode $root, ezcDocumentWikiNode $node )
     {
         $cell = $this->document->createElement( 'entry' );
         $root->appendChild( $cell );

         $this->visitParagraph( $cell, $node );
     }

     /**
      * Visit line break
      *
      * @param DOMNode $root
      * @param ezcDocumentWikiNode $node
      * @return void
      */
     protected function visitLineBreak( DOMNode $root, ezcDocumentWikiNode $node )
     {
         $root->appendChild( new DOMText( "\n" ) );

         // Mark paragraph, so it will be converted into a literallayout
         // element.
         if ( $root->tagName === 'para' )
         {
             $root->setAttribute( 'type', 'literallayout' );
         }
         else
         {
             $this->triggerError(
                 E_NOTICE, 'Intentional line break outside of paragraph ignored.',
                 null, $node->token->line, $node->token->position
             );
         }
     }

     /**
      * Visit paragraph
      *
      * @param DOMNode $root
      * @param ezcDocumentWikiNode $node
      * @return void
      */
     protected function visitParagraph( DOMNode $root, ezcDocumentWikiNode $node )
     {
         $para = $this->document->createElement( 'para' );
         $root->appendChild( $para );

         foreach ( $node->nodes as $child )
         {
             $this->visitNode( $para, $child );
         }

         // Check if paragraph should be converted into a literalayout section,
         // because it contains intentional line breaks. This marker is set by
         // the visitLineBreak() method.
         if ( $para->hasAttribute( 'type' ) &&
              ( $para->getAttribute( 'type' ) === 'literallayout' ) )
         {
             // Change paragraph into a literallayout section
             $newPara = $this->document->createElement( 'literallayout' );
             $newPara->setAttribute( 'class', 'normal' );
             $root->appendChild( $newPara );

             // Move all childs to new paragraph
             foreach ( $para->childNodes as $child )
             {
                 $newPara->appendChild( $child->cloneNode( true ) );
             }

             // Remove old paragraph
             $root->removeChild( $para );
         }
     }

     /**
      * Visit blockquote
      *
      * @param DOMNode $root
      * @param ezcDocumentWikiNode $node
      * @return void
      */
     protected function visitBlockquote( DOMNode $root, ezcDocumentWikiNode $node )
     {
         $blockquote = $this->document->createElement( 'blockquote' );
         $root->appendChild( $blockquote );

         $para = $this->document->createElement( 'para' );
         $blockquote->appendChild( $para );

         foreach ( $node->nodes as $child )
         {
             $this->visitNode( $para, $child );
         }
     }

     /**
      * Visit footnote
      *
      * @param DOMNode $root
      * @param ezcDocumentWikiNode $node
      * @return void
      */
     protected function visitFootnote( DOMNode $root, ezcDocumentWikiNode $node )
     {
         $footnote = $this->document->createElement( 'footnote' );
         $root->appendChild( $footnote );

         $para = $this->document->createElement( 'para' );
         $footnote->appendChild( $para );

         foreach ( $node->nodes as $child )
         {
             $this->visitNode( $para, $child );
         }
     }

     /**
      * Visit plugin
      *
      * @param DOMNode $root
      * @param ezcDocumentWikiNode $node
      * @return void
      */
     protected function visitPlugin( DOMNode $root, ezcDocumentWikiNode $node )
     {
         $handlerClass = $this->wiki->getPluginHandler( $node->type );
         $pluginHandler = new $handlerClass( $this->ast, $this->path, $node );
         $pluginHandler->toDocbook( $this->document, $root );
     }
 }

 ?>
	<?php
	/**
	* File containing the ezcDocumentWikiDocbookVisitor class
	*
	* 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 Document
	* @version //autogen//
	* @copyright Copyright (C) 2005-2010 eZ Systems AS. All rights reserved.
	* @license http://www.apache.org/licenses/LICENSE-2.0 Apache License, Version 2.0
	*/

	/**
	* Docbook visitor for the Wiki AST.
	*
	* @package Document
	* @version //autogen//
	*/
	class ezcDocumentWikiDocbookVisitor extends ezcDocumentWikiVisitor
	{
	/**
	* Mapping of class names to internal visitors for the respective nodes.
	*
	* @var array
	*/
	protected $complexVisitMapping = array(
	'ezcDocumentWikiTextNode' => 'visitText',
	'ezcDocumentWikiSeparatorNode' => 'visitText',
	'ezcDocumentWikiBoldNode' => 'visitEmphasisMarkup',
	'ezcDocumentWikiItalicNode' => 'visitEmphasisMarkup',
	'ezcDocumentWikiUnderlineNode' => 'visitEmphasisMarkup',
	'ezcDocumentWikiTitleNode' => 'visitTitle',
	'ezcDocumentWikiLinkNode' => 'visitLink',
	'ezcDocumentWikiExternalLinkNode' => 'visitExternalLink',
	'ezcDocumentWikiInternalLinkNode' => 'visitExternalLink',
	'ezcDocumentWikiInterWikiLinkNode' => 'visitExternalLink',
	'ezcDocumentWikiBulletListNode' => 'visitList',
	'ezcDocumentWikiEnumeratedListNode' => 'visitList',
	'ezcDocumentWikiImageNode' => 'visitImages',
	'ezcDocumentWikiLiteralBlockNode' => 'visitLiteralBlock',
	'ezcDocumentWikiInlineLiteralNode' => 'visitLiteral',
	'ezcDocumentWikiTableRowNode' => 'visitTableRow',
	'ezcDocumentWikiTableCellNode' => 'visitTableCell',
	'ezcDocumentWikiLineBreakNode' => 'visitLineBreak',
	'ezcDocumentWikiParagraphNode' => 'visitParagraph',
	'ezcDocumentWikiBlockquoteNode' => 'visitBlockquote',
	'ezcDocumentWikiFootnoteNode' => 'visitFootnote',
	'ezcDocumentWikiPluginNode' => 'visitPlugin',

	// Node markup is ignored, because there is no equivalent in docbook
	'ezcDocumentWikiDeletedNode' => 'visitChildren',
	);

	/**
	* Direct mapping of AST node class names to docbook element names.
	*
	* @var array
	*/
	protected $simpleVisitMapping = array(
	'ezcDocumentWikiSectionNode' => 'section',
	'ezcDocumentWikiInlineQuoteNode' => 'quote',
	'ezcDocumentWikiSuperscriptNode' => 'superscript',
	'ezcDocumentWikiSubscriptNode' => 'subscript',
	'ezcDocumentWikiMonospaceNode' => 'literal',
	'ezcDocumentWikiBulletListItemNode' => 'listitem',
	'ezcDocumentWikiEnumeratedListItemNode' => 'listitem',
	'ezcDocumentWikiPageBreakNode' => 'beginpage',

	'ezcDocumentWikiTableNode' => 'table',
	);

	/**
	* Array with nodes, which can be ignored during the transformation
	* process, they only provide additional information during preprocessing.
	*
	* @var array
	*/
	protected $skipNodes = array();

	/**
	* DOM document
	*
	* @var DOMDocument
	*/
	protected $document;

	/**
	* Docarate Wiki AST
	*
	* Visit the Wiki abstract syntax tree.
	*
	* @param ezcDocumentWikiDocumentNode $ast
	* @return mixed
	*/
	public function visit( ezcDocumentWikiDocumentNode $ast )
	{
	parent::visit( $ast );

	// Create article from AST
	$imp = new DOMImplementation();
	$dtd = $imp->createDocumentType( 'article', '-//OASIS//DTD DocBook XML V4.5//EN', 'http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd' );
	$this->document = $imp->createDocument( 'http://docbook.org/ns/docbook', '', $dtd );
	$this->document->formatOutput = true;

	// $root = $this->document->createElement( 'article' );
	$root = $this->document->createElementNs( 'http://docbook.org/ns/docbook', 'article' );
	$this->document->appendChild( $root );

	// Visit all childs of the AST root node.
	foreach ( $ast->nodes as $node )
	{
	$this->visitNode( $root, $node );
	}

	return $this->document;
	}

	/**
	* Visit single AST node
	*
	* Visit a single AST node, may be called for each node found anywhere
	* as child. The current position in the DOMDocument is passed by a
	* reference to the current DOMNode, which is operated on.
	*
	* @param DOMNode $root
	* @param ezcDocumentWikiNode $node
	* @return void
	*/
	protected function visitNode( DOMNode $root, ezcDocumentWikiNode $node )
	{
	// Iterate over available visitors and use them to visit the nodes.
	foreach ( $this->complexVisitMapping as $class => $method )
	{
	if ( $node instanceof $class )
	{
	return $this->$method( $root, $node );
	}
	}

	// Check if we have a simple class to element name mapping
	foreach ( $this->simpleVisitMapping as $class => $elementName )
	{
	if ( $node instanceof $class )
	{
	$element = $this->document->createElement( $elementName );
	$root->appendChild( $element );

	foreach ( $node->nodes as $child )
	{
	$this->visitNode( $element, $child );
	}

	return;
	}
	}

	// Check if you should just ignore the node for rendering
	foreach ( $this->skipNodes as $class )
	{
	if ( $node instanceof $class )
	{
	return;
	}
	}

	// We could not find any valid visitor.
	throw new ezcDocumentMissingVisitorException( get_class( $node ), $node->token->line, $node->token->position );
	}

	/**
	* Visit emphasis markup
	*
	* @param DOMNode $root
	* @param ezcDocumentWikiNode $node
	* @return void
	*/
	protected function visitEmphasisMarkup( DOMNode $root, ezcDocumentWikiNode $node )
	{
	$markup = $this->document->createElement( 'emphasis' );

	if ( $node instanceof ezcDocumentWikiBoldNode )
	{
	$markup->setAttribute( 'Role', 'strong' );
	}
	$root->appendChild( $markup );

	foreach ( $node->nodes as $child )
	{
	$this->visitNode( $markup, $child );
	}
	}

	/**
	* Visit section titles
	*
	* @param DOMNode $root
	* @param ezcDocumentWikiNode $node
	* @return void
	*/
	protected function visitTitle( DOMNode $root, ezcDocumentWikiNode $node )
	{
	$title = $this->document->createElement( 'title' );
	$root->appendChild( $title );

	foreach ( $node->nodes as $child )
	{
	$this->visitNode( $title, $child );
	}
	}

	/**
	* Visit external link node
	*
	* @param DOMNode $root
	* @param ezcDocumentWikiNode $node
	* @return void
	*/
	protected function visitExternalLink( DOMNode $root, ezcDocumentWikiNode $node )
	{
	$link = $this->document->createElement( 'ulink' );
	$link->setAttribute( 'url', $node->token->content );
	$link->appendChild( new DOMText( $node->token->content ) );
	$root->appendChild( $link );
	}

	/**
	* Visit link node
	*
	* Docbook has no support for description of links, so that the description
	* elements in the AST are omitted.
	*
	* @param DOMNode $root
	* @param ezcDocumentWikiNode $node
	* @return void
	*/
	protected function visitLink( DOMNode $root, ezcDocumentWikiNode $node )
	{
	$link = $this->document->createElement( 'ulink' );
	$link->setAttribute( 'url', $linkUrl = $this->nodeListToString( $node->link ) );
	$root->appendChild( $link );

	if ( $node->nodes === array() )
	{
	$link->appendChild( new DOMText( $linkUrl ) );
	}
	else
	{
	foreach ( $node->nodes as $child )
	{
	$this->visitNode( $link, $child );
	}
	}
	}

	/**
	* Visit list
	*
	* Ensure stacked lists are created inside another list item.
	*
	* @param DOMNode $root
	* @param ezcDocumentWikiNode $node
	* @return void
	*/
	protected function visitList( DOMNode $root, ezcDocumentWikiNode $node )
	{
	if ( ( $root->tagName === 'itemizedlist' ) \|\|
	( $root->tagName === 'orderedlist' ) )
	{
	$listitem = $this->document->createElement( 'listitem' );
	$root->appendChild( $listitem );
	$root = $listitem;
	}

	$list = $this->document->createElement(
	$node instanceof ezcDocumentWikiBulletListNode ? 'itemizedlist' : 'orderedlist'
	);
	$root->appendChild( $list );

	foreach ( $node->nodes as $child )
	{
	$this->visitNode( $list, $child );
	}
	}

	/**
	* Is inline node?
	*
	* Check if contents of the current node are a inline node
	*
	* @param DOMNode $node
	* @return bool
	*/
	protected function isInlineNode( DOMNode $node )
	{
	return in_array( $node->tagName, array(
	'para',
	'acronym',
	'anchor',
	'author',
	'citation',
	'email',
	'emphasis',
	'footnote',
	'footnoteref',
	'inlinemediaobject',
	'literal',
	'quote',
	'subscript',
	'superscript',
	'link',
	'ulink',
	) );
	}

	/**
	* Visit images
	*
	* @param DOMNode $root
	* @param ezcDocumentWikiNode $node
	* @return void
	*/
	protected function visitImages( DOMNode $root, ezcDocumentWikiNode $node )
	{
	$media = $this->document->createElement( $this->isInlineNode( $root ) ? 'inlinemediaobject' : 'mediaobject' );
	$root->appendChild( $media );

	$imageObject = $this->document->createElement( 'imageobject' );
	$media->appendChild( $imageObject );

	$image = $this->document->createElement( 'imagedata' );
	$image->setAttribute( 'fileref', $this->nodeListToString( $node->resource ) );
	$imageObject->appendChild( $image );

	// Handle optional settings on images
	if ( $node->title !== array() )
	{
	$text = $this->document->createElement( 'textobject' );
	$media->appendChild( $text );
	foreach ( $node->title as $child )
	{
	$this->visitNode( $text, $child );
	}
	}

	if ( $node->width )
	{
	$image->setAttribute( 'width', (int) $node->width );
	}

	if ( $node->height )
	{
	$image->setAttribute( 'depth', (int) $node->height );
	}

	if ( $node->alignement )
	{
	$image->setAttribute( 'align', $node->alignement );
	}

	foreach ( $node->nodes as $child )
	{
	$this->visitNode( $list, $child );
	}
	}

	/**
	* Visit literal block
	*
	* @param DOMNode $root
	* @param ezcDocumentWikiNode $node
	* @return void
	*/
	protected function visitLiteralBlock( DOMNode $root, ezcDocumentWikiNode $node )
	{
	$literal = $this->document->createElement( 'literallayout', htmlspecialchars( $node->token->content ) );
	$root->appendChild( $literal );
	}

	/**
	* Visit literal
	*
	* @param DOMNode $root
	* @param ezcDocumentWikiNode $node
	* @return void
	*/
	protected function visitLiteral( DOMNode $root, ezcDocumentWikiNode $node )
	{
	$literal = $this->document->createElement( 'literal', htmlspecialchars( $node->token->content ) );
	$root->appendChild( $literal );
	}

	/**
	* Visit table row
	*
	* Visit a table row and decide if it belongs into a tbody or a thead
	* section.
	*
	* @param DOMNode $root
	* @param ezcDocumentWikiNode $node
	* @return void
	*/
	protected function visitTableRow( DOMNode $root, ezcDocumentWikiNode $node )
	{
	$header = true;
	foreach ( $node->nodes as $cell )
	{
	$header = $header && $cell->header;
	}

	// Get last child element in table
	if ( !( $last = $root->lastChild ) \|\|
	( $last->nodeType !== XML_ELEMENT_NODE ) )
	{
	$last = false;
	}

	$type = $header ? 'thead' : 'tbody';
	if ( ( $last === false ) \|\|
	( $last->tagName !== $type ) )
	{
	$wrapper = $this->document->createElement( $type );
	$root->appendChild( $wrapper );
	$root = $wrapper;
	}
	else
	{
	$root = $last;
	}

	$row = $this->document->createElement( 'row' );
	$root->appendChild( $row );

	foreach ( $node->nodes as $child )
	{
	$this->visitNode( $row, $child );
	}
	}


	/**
	* Visit table cell
	*
	* Visit a table cell and additionally always create an inner paragraph.
	*
	* @param DOMNode $root
	* @param ezcDocumentWikiNode $node
	* @return void
	*/
	protected function visitTableCell( DOMNode $root, ezcDocumentWikiNode $node )
	{
	$cell = $this->document->createElement( 'entry' );
	$root->appendChild( $cell );

	$this->visitParagraph( $cell, $node );
	}

	/**
	* Visit line break
	*
	* @param DOMNode $root
	* @param ezcDocumentWikiNode $node
	* @return void
	*/
	protected function visitLineBreak( DOMNode $root, ezcDocumentWikiNode $node )
	{
	$root->appendChild( new DOMText( "\n" ) );

	// Mark paragraph, so it will be converted into a literallayout
	// element.
	if ( $root->tagName === 'para' )
	{
	$root->setAttribute( 'type', 'literallayout' );
	}
	else
	{
	$this->triggerError(
	E_NOTICE, 'Intentional line break outside of paragraph ignored.',
	null, $node->token->line, $node->token->position
	);
	}
	}

	/**
	* Visit paragraph
	*
	* @param DOMNode $root
	* @param ezcDocumentWikiNode $node
	* @return void
	*/
	protected function visitParagraph( DOMNode $root, ezcDocumentWikiNode $node )
	{
	$para = $this->document->createElement( 'para' );
	$root->appendChild( $para );

	foreach ( $node->nodes as $child )
	{
	$this->visitNode( $para, $child );
	}

	// Check if paragraph should be converted into a literalayout section,
	// because it contains intentional line breaks. This marker is set by
	// the visitLineBreak() method.
	if ( $para->hasAttribute( 'type' ) &&
	( $para->getAttribute( 'type' ) === 'literallayout' ) )
	{
	// Change paragraph into a literallayout section
	$newPara = $this->document->createElement( 'literallayout' );
	$newPara->setAttribute( 'class', 'normal' );
	$root->appendChild( $newPara );

	// Move all childs to new paragraph
	foreach ( $para->childNodes as $child )
	{
	$newPara->appendChild( $child->cloneNode( true ) );
	}

	// Remove old paragraph
	$root->removeChild( $para );
	}
	}

	/**
	* Visit blockquote
	*
	* @param DOMNode $root
	* @param ezcDocumentWikiNode $node
	* @return void
	*/
	protected function visitBlockquote( DOMNode $root, ezcDocumentWikiNode $node )
	{
	$blockquote = $this->document->createElement( 'blockquote' );
	$root->appendChild( $blockquote );

	$para = $this->document->createElement( 'para' );
	$blockquote->appendChild( $para );

	foreach ( $node->nodes as $child )
	{
	$this->visitNode( $para, $child );
	}
	}

	/**
	* Visit footnote
	*
	* @param DOMNode $root
	* @param ezcDocumentWikiNode $node
	* @return void
	*/
	protected function visitFootnote( DOMNode $root, ezcDocumentWikiNode $node )
	{
	$footnote = $this->document->createElement( 'footnote' );
	$root->appendChild( $footnote );

	$para = $this->document->createElement( 'para' );
	$footnote->appendChild( $para );

	foreach ( $node->nodes as $child )
	{
	$this->visitNode( $para, $child );
	}
	}

	/**
	* Visit plugin
	*
	* @param DOMNode $root
	* @param ezcDocumentWikiNode $node
	* @return void
	*/
	protected function visitPlugin( DOMNode $root, ezcDocumentWikiNode $node )
	{
	$handlerClass = $this->wiki->getPluginHandler( $node->type );
	$pluginHandler = new $handlerClass( $this->ast, $this->path, $node );
	$pluginHandler->toDocbook( $this->document, $root );
	}
	}

	?>