HTMLBBCodeParser.php 24.5 KB
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<?php
/* vim: set expandtab tabstop=4 shiftwidth=4: */
// +----------------------------------------------------------------------+
// | PHP Version 4                                                        |
// +----------------------------------------------------------------------+
// | Copyright (c) 1997-2003 The PHP Group                                |
// +----------------------------------------------------------------------+
// | This source file is subject to version 2.02 of the PHP license,      |
// | that is bundled with this package in the file LICENSE, and is        |
// | available at through the world-wide-web at                           |
// | http://www.php.net/license/2_02.txt.                                 |
// | If you did not receive a copy of the PHP license and are unable to   |
// | obtain it through the world-wide-web, please send a note to          |
// | license@php.net so we can mail you a copy immediately.               |
// +----------------------------------------------------------------------+
// | Author: Stijn de Reede <sjr@gmx.co.uk>                               |
// +----------------------------------------------------------------------+
//
// $Id: BBCodeParser.php,v 1.17 2007/07/02 18:46:30 cweiske Exp $
//
// Modified by SilverStripe silverstripe.com

/**
 * @package framework
 * @subpackage misc
 * @author   Stijn de Reede  <sjr@gmx.co.uk> , SilverStripe
 *
 *
 * This is a parser to replace UBB style tags with their html equivalents. It
 * does not simply do some regex calls, but is complete stack based
 * parse engine. This ensures that all tags are properly nested, if not,
 * extra tags are added to maintain the nesting. This parser should only produce
 * xhtml 1.0 compliant code. All tags are validated and so are all their attributes.
 * It should be easy to extend this parser with your own tags, see the _definedTags
 * format description below.
 *
 *
 * Usage:
 * $parser = new SSHTMLBBCodeParser();
 * $parser->setText('normal [b]bold[/b] and normal again');
 * $parser->parse();
 * echo $parser->getParsed();
 * or:
 * $parser = new SSHTMLBBCodeParser();
 * echo $parser->qparse('normal [b]bold[/b] and normal again');
 * or:
 * echo SSHTMLBBCodeParser::staticQparse('normal [b]bold[/b] and normal again');
 *
 *
 * Setting the options from the ini file:
 * $config = parse_ini_file('BBCodeParser.ini', true);
 *  $options = &PEAR::getStaticProperty('SSHTMLBBCodeParser', '_options');
 * $options = $config['SSHTMLBBCodeParser'];
 * unset($options);
 */
class SSHTMLBBCodeParser
{
	/**
	 * An array of tags parsed by the engine, should be overwritten by filters
	 *
	 * @access   private
	 * @var      array
	 */
	var $_definedTags  = array();

	/**
	 * A string containing the input
	 *
	 * @access   private
	 * @var      string
	 */
	var $_text          = '';

	/**
	 * A string containing the preparsed input
	 *
	 * @access   private
	 * @var      string
	 */
	var $_preparsed     = '';

	/**
	 * An array tags and texts build from the input text
	 *
	 * @access   private
	 * @var      array
	 */
	var $_tagArray      = array();

	/**
	 * A string containing the parsed version of the text
	 *
	 * @access   private
	 * @var      string
	 */
	var $_parsed        = '';

	/**
	 * An array of options, filled by an ini file or through the contructor
	 *
	 * @access   private
	 * @var      array
	 */
	var $_options = array(
		'quotestyle'    => 'double',
		'quotewhat'     => 'all',
		'open'          => '[',
		'close'         => ']',
		'xmlclose'      => true,
		'filters'       => 'Basic'
	);

	/**
	 * An array of filters used for parsing
	 *
	 * @access   private
	 * @var      array
	 */
	var $_filters       = array();

	/**
	 * Constructor, initialises the options and filters
	 *
	 * Sets the private variable _options with base options defined with
	 * &PEAR::getStaticProperty(), overwriting them with (if present)
	 * the argument to this method.
	 * Then it sets the extra options to properly escape the tag
	 * characters in preg_replace() etc. The set options are
	 * then stored back with &PEAR::getStaticProperty(), so that the filter
	 * classes can use them.
	 * All the filters in the options are initialised and their defined tags
	 * are copied into the private variable _definedTags.
	 *
	 * @param    array           options to use, can be left out
	 * @return   none
	 * @access   public
	 * @author   Stijn de Reede  <sjr@gmx.co.uk>
	 */
	public function SSHTMLBBCodeParser($options = array())
	{
		// set the already set options
		$baseoptions = &SSHTMLBBCodeParser::getStaticProperty('SSHTMLBBCodeParser', '_options');
		if (is_array($baseoptions)) {
			foreach ($baseoptions as  $k => $v)  {
				$this->_options[$k] = $v;
			}
		}

		// set the options passed as an argument
		foreach ($options as $k => $v )  {
			$this->_options[$k] = $v;
		}

		// add escape open and close chars to the options for preg escaping
		$preg_escape = '\^$.[]|()?*+{}';
		if ($this->_options['open'] != '' && strpos($preg_escape, $this->_options['open'])) {
			$this->_options['open_esc'] = "\\".$this->_options['open'];
		} else {
			$this->_options['open_esc'] = $this->_options['open'];
		}
		if ($this->_options['close'] != '' && strpos($preg_escape, $this->_options['close'])) {
			$this->_options['close_esc'] = "\\".$this->_options['close'];
		} else {
			$this->_options['close_esc'] = $this->_options['close'];
		}

		// set the options back so that child classes can use them */
		$baseoptions = $this->_options;
		unset($baseoptions);

		// return if this is a subclass
		if (is_subclass_of($this, 'SSHTMLBBCodeParser_Filter')) {
			return;
		}

		// extract the definedTags from subclasses */
		$this->addFilters($this->_options['filters']);
	}
	
	static function &getStaticProperty($class, $var)
	{
		static $properties;
		if (!isset($properties[$class])) {
			$properties[$class] = array();
		}
		if (!array_key_exists($var, $properties[$class])) {
			$properties[$class][$var] = null;
		}
		return $properties[$class][$var];
	}

	/**
	 * Option setter
	 *
	 * @param string option name
	 * @param mixed  option value
	 * @author Lorenzo Alberton <l.alberton@quipo.it>
	 */
	public function setOption($name, $value)
	{
		$this->_options[$name] = $value;
	}

	/**
	 * Add a new filter
	 *
	 * @param string filter
	 * @author Lorenzo Alberton <l.alberton@quipo.it>
	 */
	public function addFilter($filter)
	{
		$filter = ucfirst($filter);
		if (!array_key_exists($filter, $this->_filters)) {
			$class = 'SSHTMLBBCodeParser_Filter_'.$filter;
			if (fopen('BBCodeParser/Filter/'.$filter.'.php','r',true)) { 
				include_once 'BBCodeParser/Filter/'.$filter.'.php'; 
			}
			if (!class_exists($class)) {

				//PEAR::raiseError("Failed to load filter $filter", null, PEAR_ERROR_DIE);
			}
			else {
				$this->_filters[$filter] = new $class; 
				$this->_definedTags = array_merge( 
					$this->_definedTags, 
					$this->_filters[$filter]->_definedTags 
				);
			}
		}

	}

	/**
	 * Remove an existing filter
	 *
	 * @param string $filter
	 * @author Lorenzo Alberton <l.alberton@quipo.it>
	 */
	public function removeFilter($filter)
	{
		$filter = ucfirst(trim($filter));
		if (!empty($filter) && array_key_exists($filter, $this->_filters)) {
			unset($this->_filters[$filter]);
		}
		// also remove the related $this->_definedTags for this filter,
		// preserving the others
		$this->_definedTags = array();
		foreach (array_keys($this->_filters) as $filter) {
			$this->_definedTags = array_merge(
				$this->_definedTags,
				$this->_filters[$filter]->_definedTags
			);
		}
	}

	/**
	 * Add new filters
	 *
	 * @param mixed (array or string)
	 * @return boolean true if all ok, false if not.
	 * @author Lorenzo Alberton <l.alberton@quipo.it>
	 */
	public function addFilters($filters)
	{
		if (is_string($filters)) {
			//comma-separated list
			if (strpos($filters, ',') !== false) {
				$filters = explode(',', $filters);
			} else {
				$filters = array($filters);
			}
		}
		if (!is_array($filters)) {
			//invalid format
			return false;
		}
		foreach ($filters as $filter) {
			if (trim($filter)){
				$this->addFilter($filter);
			}
		}
		return true;
	}

	/**
	 * Executes statements before the actual array building starts
	 *
	 * This method should be overwritten in a filter if you want to do
	 * something before the parsing process starts. This can be useful to
	 * allow certain short alternative tags which then can be converted into
	 * proper tags with preg_replace() calls.
	 * The main class walks through all the filters and and calls this
	 * method. The filters should modify their private $_preparsed
	 * variable, with input from $_text.
	 *
	 * @return   none
	 * @access   private
	 * @see      $_text
	 * @author   Stijn de Reede  <sjr@gmx.co.uk>
	 */
	public function _preparse()
	{
		// default: assign _text to _preparsed, to be overwritten by filters
		$this->_preparsed = $this->_text;

		// return if this is a subclass
		if (is_subclass_of($this, 'SSHTMLBBCodeParser')) {
			return;
		}

		// walk through the filters and execute _preparse
		foreach ($this->_filters as $filter) {
			$filter->setText($this->_preparsed);
			$filter->_preparse();
			$this->_preparsed = $filter->getPreparsed();
		}
	}

	/**
	 * Builds the tag array from the input string $_text
	 *
	 * An array consisting of tag and text elements is contructed from the
	 * $_preparsed variable. The method uses _buildTag() to check if a tag is
	 * valid and to build the actual tag to be added to the tag array.
	 *
	 * @todo - rewrite whole method, as this one is old and probably slow
	 *       - see if a recursive method would be better than an iterative one
	 *
	 * @return   none
	 * @access   private
	 * @see      _buildTag()
	 * @see      $_text
	 * @see      $_tagArray
	 * @author   Stijn de Reede  <sjr@gmx.co.uk>
	 */
	public function _buildTagArray()
	{
		$this->_tagArray = array();
		$str = $this->_preparsed;
		$strPos = 0;
		$strLength = strlen($str);

		while (($strPos < $strLength)) {
			$tag = array();
			$openPos = strpos($str, $this->_options['open'], $strPos);
			if ($openPos === false) {
				$openPos = $strLength;
				$nextOpenPos = $strLength;
			}
			if ($openPos + 1 > $strLength) {
				$nextOpenPos = $strLength;
			} else {
				$nextOpenPos = strpos($str, $this->_options['open'], $openPos + 1);
				if ($nextOpenPos === false) {
					$nextOpenPos = $strLength;
				}
			}
			$closePos = strpos($str, $this->_options['close'], $strPos);
			if ($closePos === false) {
				$closePos = $strLength + 1;
			}

			if ($openPos == $strPos) {
				if (($nextOpenPos < $closePos)) {
					// new open tag before closing tag: treat as text
					$newPos = $nextOpenPos;
					$tag['text'] = substr($str, $strPos, $nextOpenPos - $strPos);
					$tag['type'] = 0;
				} else {
					// possible valid tag
					$newPos = $closePos + 1;
					$newTag = $this->_buildTag(substr($str, $strPos, $closePos - $strPos + 1));
					if (($newTag !== false)) {
						$tag = $newTag;
					} else {
						// no valid tag after all
						$tag['text'] = substr($str, $strPos, $closePos - $strPos + 1);
						$tag['type'] = 0;
					}
				}
			} else {
				// just text
				$newPos = $openPos;
				$tag['text'] = substr($str, $strPos, $openPos - $strPos);
				$tag['type'] = 0;
			}

			// join 2 following text elements
			if ($tag['type'] === 0 && isset($prev) && $prev['type'] === 0) {
				$tag['text'] = $prev['text'].$tag['text'];
				array_pop($this->_tagArray);
			}

			$this->_tagArray[] = $tag;
			$prev = $tag;
			$strPos = $newPos;
		}
	}

	/**
	 * Builds a tag from the input string
	 *
	 * This method builds a tag array based on the string it got as an
	 * argument. If the tag is invalid, <false> is returned. The tag
	 * attributes are extracted from the string and stored in the tag
	 * array as an associative array.
	 *
	 * @param    string          string to build tag from
	 * @return   array           tag in array format
	 * @access   private
	 * @see      _buildTagArray()
	 * @author   Stijn de Reede  <sjr@gmx.co.uk>
	 */
	public function _buildTag($str)
	{
		$tag = array('text' => $str, 'attributes' => array());

		if (substr($str, 1, 1) == '/') {        // closing tag

			$tag['tag'] = strtolower(substr($str, 2, strlen($str) - 3));
			if (!in_array($tag['tag'], array_keys($this->_definedTags))) {
				return false;                   // nope, it's not valid
			} else {
				$tag['type'] = 2;
				return $tag;
			}
		} else {                                // opening tag

			$tag['type'] = 1;
			if (strpos($str, ' ') && (strpos($str, '=') === false)) {
				return false;                   // nope, it's not valid
			}

			// tnx to Onno for the regex
			// split the tag with arguments and all
			$oe = $this->_options['open_esc'];
			$ce = $this->_options['close_esc'];
			$tagArray = array();
			if (preg_match("!$oe([a-z0-9]+)[^$ce]*$ce!i", $str, $tagArray) == 0) {
				return false;
			}
			$tag['tag'] = strtolower($tagArray[1]);
			if (!in_array($tag['tag'], array_keys($this->_definedTags))) {
				return false;                   // nope, it's not valid
			}

			// tnx to Onno for the regex
			// validate the arguments
			$attributeArray = array();
			$regex = "![\s$oe]([a-z0-9]+)=(\"[^\s$ce]+\"|[^\s$ce]";
			if ($tag['tag'] != 'url') {
				$regex .= "[^=]";
			}
			$regex .= "+)(?=[\s$ce])!i";
			preg_match_all($regex, $str, $attributeArray, PREG_SET_ORDER);
			foreach ($attributeArray as $attribute) {
				$attNam = strtolower($attribute[1]);
				if (in_array($attNam, array_keys($this->_definedTags[$tag['tag']]['attributes']))) {
					if ($attribute[2][0] == '"' && $attribute[2][strlen($attribute[2])-1] == '"') {
						$tag['attributes'][$attNam] = substr($attribute[2], 1, -1);
					} else {
						$tag['attributes'][$attNam] = $attribute[2];
					}
				}
			}
			return $tag;
		}
	}

	/**
	 * Validates the tag array, regarding the allowed tags
	 *
	 * While looping through the tag array, two following text tags are
	 * joined, and it is checked that the tag is allowed inside the
	 * last opened tag.
	 * By remembering what tags have been opened it is checked that
	 * there is correct (xml compliant) nesting.
	 * In the end all still opened tags are closed.
	 *
	 * @return   none
	 * @access   private
	 * @see      _isAllowed()
	 * @see      $_tagArray
	 * @author   Stijn de Reede  <sjr@gmx.co.uk>, Seth Price <seth@pricepages.org>
	 */
	public function _validateTagArray()
	{
		$newTagArray = array();
		$openTags = array();
		foreach ($this->_tagArray as $tag) {
			$prevTag = end($newTagArray);
			switch ($tag['type']) {
			case 0:
				if (($child = $this->_childNeeded(end($openTags), 'text')) &&
					$child !== false &&
					/*
					 * No idea what to do in this case: A child is needed, but
					 * no valid one is returned. We'll ignore it here and live
					 * with it until someone reports a valid bug.
					 */
					$child !== true )
				{
					if (trim($tag['text']) == '') {
						//just an empty indentation or newline without value?
						continue;
					}
					$newTagArray[] = $child;
					$openTags[] = $child['tag'];
				}
				if ($prevTag['type'] === 0) {
					$tag['text'] = $prevTag['text'].$tag['text'];
					array_pop($newTagArray);
				}
				$newTagArray[] = $tag;
				break;

			case 1:
				if (!$this->_isAllowed(end($openTags), $tag['tag']) ||
					($parent = $this->_parentNeeded(end($openTags), $tag['tag'])) === true ||
					($child  = $this->_childNeeded(end($openTags),  $tag['tag'])) === true) {
					$tag['type'] = 0;
					if ($prevTag['type'] === 0) {
						$tag['text'] = $prevTag['text'].$tag['text'];
						array_pop($newTagArray);
					}
				} else {
					if ($parent) {
						/*
						 * Avoid use of parent if we can help it. If we are
						 * trying to insert a new parent, but the current tag is
						 * the same as the previous tag, then assume that the
						 * previous tag structure is valid, and add this tag as
						 * a sibling. To add as a sibling, we need to close the
						 * current tag.
						 */
						if ($tag['tag'] == end($openTags)){
							$newTagArray[] = $this->_buildTag('[/'.$tag['tag'].']');
							array_pop($openTags);
						} else {
							$newTagArray[] = $parent;
							$openTags[] = $parent['tag'];
						}
					}
					if ($child) {
						$newTagArray[] = $child;
						$openTags[] = $child['tag'];
					}
					$openTags[] = $tag['tag'];
				}
				$newTagArray[] = $tag;
				break;

			case 2:
				if (($tag['tag'] == end($openTags) || $this->_isAllowed(end($openTags), $tag['tag']))) {
					if (in_array($tag['tag'], $openTags)) {
						$tmpOpenTags = array();
						while (end($openTags) != $tag['tag']) {
							$newTagArray[] = $this->_buildTag('[/'.end($openTags).']');
							$tmpOpenTags[] = end($openTags);
							array_pop($openTags);
						}
						$newTagArray[] = $tag;
						array_pop($openTags);
						/* why is this here? it just seems to break things
						 * (nested lists where closing tags need to be
						 * generated)
						while (end($tmpOpenTags)) {
							$tmpTag = $this->_buildTag('['.end($tmpOpenTags).']');
							$newTagArray[] = $tmpTag;
							$openTags[] = $tmpTag['tag'];
							array_pop($tmpOpenTags);
						}*/
					}
				} else {
					$tag['type'] = 0;
					if ($prevTag['type'] === 0) {
						$tag['text'] = $prevTag['text'].$tag['text'];
						array_pop($newTagArray);
					}
					$newTagArray[] = $tag;
				}
				break;
			}
		}
		while (end($openTags)) {
			$newTagArray[] = $this->_buildTag('[/'.end($openTags).']');
			array_pop($openTags);
		}
		$this->_tagArray = $newTagArray;
	}

	/**
	 * Checks to see if a parent is needed
	 *
	 * Checks to see if the current $in tag has an appropriate parent. If it
	 * does, then it returns false. If a parent is needed, then it returns the
	 * first tag in the list to add to the stack.
	 *
	 * @param    array           tag that is on the outside
	 * @param    array           tag that is on the inside
	 * @return   boolean         false if not needed, tag if needed, true if out
	 *                           of  our minds
	 * @access   private
	 * @see      _validateTagArray()
	 * @author   Seth Price <seth@pricepages.org>
	 */
	public function _parentNeeded($out, $in)
	{
		if (!isset($this->_definedTags[$in]['parent']) ||
			($this->_definedTags[$in]['parent'] == 'all')
		) {
			return false;
		}

		$ar = explode('^', $this->_definedTags[$in]['parent']);
		$tags = explode(',', $ar[1]);
		if ($ar[0] == 'none'){
			if ($out && in_array($out, $tags)) {
				return false;
			}
			//Create a tag from the first one on the list
			return $this->_buildTag('['.$tags[0].']');
		}
		if ($ar[0] == 'all' && $out && !in_array($out, $tags)) {
			return false;
		}
		// Tag is needed, we don't know which one. We could make something up,
		// but it would be so random, I think that it would be worthless.
		return true;
	}

	/**
	 * Checks to see if a child is needed
	 *
	 * Checks to see if the current $out tag has an appropriate child. If it
	 * does, then it returns false. If a child is needed, then it returns the
	 * first tag in the list to add to the stack.
	 *
	 * @param    array           tag that is on the outside
	 * @param    array           tag that is on the inside
	 * @return   boolean         false if not needed, tag if needed, true if out
	 *                           of our minds
	 * @access   private
	 * @see      _validateTagArray()
	 * @author   Seth Price <seth@pricepages.org>
	 */
	public function _childNeeded($out, $in)
	{
		if (!isset($this->_definedTags[$out]['child']) ||
			($this->_definedTags[$out]['child'] == 'all')
		) {
			return false;
		}

		$ar = explode('^', $this->_definedTags[$out]['child']);
		$tags = explode(',', $ar[1]);
		if ($ar[0] == 'none'){
			if ($in && in_array($in, $tags)) {
				return false;
			}
			//Create a tag from the first one on the list
			return $this->_buildTag('['.$tags[0].']');
		}
		if ($ar[0] == 'all' && $in && !in_array($in, $tags)) {
			return false;
		}
		// Tag is needed, we don't know which one. We could make something up,
		// but it would be so random, I think that it would be worthless.
		return true;
	}

	/**
	 * Checks to see if a tag is allowed inside another tag
	 *
	 * The allowed tags are extracted from the private _definedTags array.
	 *
	 * @param    array           tag that is on the outside
	 * @param    array           tag that is on the inside
	 * @return   boolean         return true if the tag is allowed, false
	 *                           otherwise
	 * @access   private
	 * @see      _validateTagArray()
	 * @author   Stijn de Reede  <sjr@gmx.co.uk>
	 */
	public function _isAllowed($out, $in)
	{
		if (!$out || ($this->_definedTags[$out]['allowed'] == 'all')) {
			return true;
		}
		if ($this->_definedTags[$out]['allowed'] == 'none') {
			return false;
		}

		$ar = explode('^', $this->_definedTags[$out]['allowed']);
		$tags = explode(',', $ar[1]);
		if ($ar[0] == 'none' && in_array($in, $tags)) {
			return true;
		}
		if ($ar[0] == 'all'  && in_array($in, $tags)) {
			return false;
		}
		return false;
	}

	/**
	 * Builds a parsed string based on the tag array
	 *
	 * The correct html and attribute values are extracted from the private
	 * _definedTags array.
	 *
	 * @return   none
	 * @access   private
	 * @see      $_tagArray
	 * @see      $_parsed
	 * @author   Stijn de Reede  <sjr@gmx.co.uk>
	 */
	public function _buildParsedString()
	{
		$this->_parsed = '';
		foreach ($this->_tagArray as $tag) {
			switch ($tag['type']) {

			// just text
			case 0:
				$this->_parsed .= $tag['text'];
				break;

			// opening tag
			case 1:
				$this->_parsed .= '<'.$this->_definedTags[$tag['tag']]['htmlopen'];
				if ($this->_options['quotestyle'] == 'single') $q = "'";
				if ($this->_options['quotestyle'] == 'double') $q = '"';
				foreach ($tag['attributes'] as $a => $v) {
					//prevent XSS attacks. IMHO this is not enough, though...
					//@see http://pear.php.net/bugs/bug.php?id=5609
					$v = preg_replace('#(script|about|applet|activex|chrome):#is', "\\1&#058;", $v);
					$v = htmlspecialchars($v);
					$v = str_replace('&amp;amp;', '&amp;', $v);

					if (($this->_options['quotewhat'] == 'nothing') ||
						(($this->_options['quotewhat'] == 'strings') && is_numeric($v))
					) {
						$this->_parsed .= ' '.sprintf($this->_definedTags[$tag['tag']]['attributes'][$a], $v, '');
					} else {
						$this->_parsed .= ' '.sprintf($this->_definedTags[$tag['tag']]['attributes'][$a], $v, $q);
					}
				}
				if ($this->_definedTags[$tag['tag']]['htmlclose'] == '' && $this->_options['xmlclose']) {
					$this->_parsed .= ' /';
				}
				$this->_parsed .= '>';
				break;

			// closing tag
			case 2:
				if ($this->_definedTags[$tag['tag']]['htmlclose'] != '') {
					$this->_parsed .= '</'.$this->_definedTags[$tag['tag']]['htmlclose'].'>';
				}
				break;
			}
		}
	}

	/**
	 * Sets text in the object to be parsed
	 *
	 * @param    string          the text to set in the object
	 * @return   none
	 * @access   public
	 * @see      getText()
	 * @see      $_text
	 * @author   Stijn de Reede  <sjr@gmx.co.uk>
	 */
	public function setText($str)
	{
		$this->_text = $str;
	}

	/**
	 * Gets the unparsed text from the object
	 *
	 * @return   string          the text set in the object
	 * @access   public
	 * @see      setText()
	 * @see      $_text
	 * @author   Stijn de Reede  <sjr@gmx.co.uk>
	 */
	public function getText()
	{
		return $this->_text;
	}

	/**
	 * Gets the preparsed text from the object
	 *
	 * @return   string          the text set in the object
	 * @access   public
	 * @see      _preparse()
	 * @see      $_preparsed
	 * @author   Stijn de Reede  <sjr@gmx.co.uk>
	 */
	public function getPreparsed()
	{
		return $this->_preparsed;
	}

	/**
	 * Gets the parsed text from the object
	 *
	 * @return   string          the parsed text set in the object
	 * @access   public
	 * @see      parse()
	 * @see      $_parsed
	 * @author   Stijn de Reede  <sjr@gmx.co.uk>
	 */
	public function getParsed()
	{
		return $this->_parsed;
	}

	/**
	 * Parses the text set in the object
	 *
	 * @return   none
	 * @access   public
	 * @see      _preparse()
	 * @see      _buildTagArray()
	 * @see      _validateTagArray()
	 * @see      _buildParsedString()
	 * @author   Stijn de Reede  <sjr@gmx.co.uk>
	 */
	public function parse()
	{
		$this->_preparse();
		$this->_buildTagArray();
		$this->_validateTagArray();
		$this->_buildParsedString();
	}

	/**
	 * Quick method to do setText(), parse() and getParsed at once
	 *
	 * @return   none
	 * @access   public
	 * @see      parse()
	 * @see      $_text
	 * @author   Stijn de Reede  <sjr@gmx.co.uk>
	 */
	public function qparse($str)
	{
		$this->_text = $str;
		$this->parse();
		return $this->_parsed;
	}

	/**
	 * Quick static method to do setText(), parse() and getParsed at once
	 *
	 * @return   none
	 * @access   public
	 * @see      parse()
	 * @see      $_text
	 * @author   Stijn de Reede  <sjr@gmx.co.uk>
	 */
	public function staticQparse($str)
	{
		$p = new SSHTMLBBCodeParser();
		$str = $p->qparse($str);
		unset($p);
		return $str;
	}
}