• '; } elseif ( '#' === $char ) { $result .= '
  1. '; } elseif ( ':' === $char ) { $result .= '

     '; } elseif ( ';' === $char ) { $result .= '

     '; $this->mDTopen = true; } else { $result = ''; } return $result; } /** * TODO: document * @param $char String * @private * * @return string */ function nextItem( $char ) { if ( '*' === $char || '#' === $char ) { return '

  2. '; } elseif ( ':' === $char || ';' === $char ) { $close = ''; if ( $this->mDTopen ) { $close = ''; } if ( ';' === $char ) { $this->mDTopen = true; return $close . '
     '; } else { $this->mDTopen = false; return $close . '
     '; } } return ''; } /** * TODO: document * @param $char String * @private * * @return string */ function closeList( $char ) { if ( '*' === $char ) { $text = '

 element, scan for and figure out what prefixes are there.
			if ( !$this->mInPre ) {
				# Multiple prefixes may abut each other for nested lists.
				$prefixLength = strspn( $oLine, '*#:;' );
				$prefix = substr( $oLine, 0, $prefixLength );

				# eh?
				# ; and : are both from definition-lists, so they're equivalent
				#  for the purposes of determining whether or not we need to open/close
				#  elements.
				$prefix2 = str_replace( ';', ':', $prefix );
				$t = substr( $oLine, $prefixLength );
				$this->mInPre = (bool)$preOpenMatch;
			} else {
				# Don't interpret any other prefixes in preformatted text
				$prefixLength = 0;
				$prefix = $prefix2 = '';
				$t = $oLine;
			}

			# List generation
			if ( $prefixLength && $lastPrefix === $prefix2 ) {
				# Same as the last item, so no need to deal with nesting or opening stuff
				$output .= $this->nextItem( substr( $prefix, -1 ) );
				$paragraphStack = false;

				if ( substr( $prefix, -1 ) === ';') {
					# The one nasty exception: definition lists work like this:
					# ; title : definition text
					# So we check for : in the remainder text to split up the
					# title and definition, without b0rking links.
					$term = $t2 = '';
					if ( $this->findColonNoLinks( $t, $term, $t2 ) !== false ) {
						$t = $t2;
						$output .= $term . $this->nextItem( ':' );
					}
				}
			} elseif ( $prefixLength || $lastPrefixLength ) {
				# We need to open or close prefixes, or both.

				# Either open or close a level...
				$commonPrefixLength = $this->getCommon( $prefix, $lastPrefix );
				$paragraphStack = false;

				# Close all the prefixes which aren't shared.
				while ( $commonPrefixLength < $lastPrefixLength ) {
					$output .= $this->closeList( $lastPrefix[$lastPrefixLength-1] );
					--$lastPrefixLength;
				}

				# Continue the current prefix if appropriate.
				if ( $prefixLength <= $commonPrefixLength && $commonPrefixLength > 0 ) {
					$output .= $this->nextItem( $prefix[$commonPrefixLength-1] );
				}

				# Open prefixes where appropriate.
				while ( $prefixLength > $commonPrefixLength ) {
					$char = substr( $prefix, $commonPrefixLength, 1 );
					$output .= $this->openList( $char );

					if ( ';' === $char ) {
						# @todo FIXME: This is dupe of code above
						if ( $this->findColonNoLinks( $t, $term, $t2 ) !== false ) {
							$t = $t2;
							$output .= $term . $this->nextItem( ':' );
						}
					}
					++$commonPrefixLength;
				}
				$lastPrefix = $prefix2;
			}

			# If we have no prefixes, go to paragraph mode.
			if ( 0 == $prefixLength ) {
				wfProfileIn( __METHOD__."-paragraph" );
				# No prefix (not in list)--go to paragraph mode
				# XXX: use a stack for nestable elements like span, table and div
				$openmatch = preg_match('/(?:mUniqPrefix.'-pre|<\\/li|<\\/ul|<\\/ol|<\\/?center)/iS', $t );
				if ( $openmatch or $closematch ) {
					$paragraphStack = false;
					# TODO bug 5718: paragraph closed
					$output .= $this->closeParagraph();
					if ( $preOpenMatch and !$preCloseMatch ) {
						$this->mInPre = true;
					}
					$inBlockElem = !$closematch;
				} elseif ( !$inBlockElem && !$this->mInPre ) {
					if ( ' ' == substr( $t, 0, 1 ) and ( $this->mLastSection === 'pre' || trim( $t ) != '' ) ) {
						# pre
						if ( $this->mLastSection !== 'pre' ) {
							$paragraphStack = false;
							$output .= $this->closeParagraph().'
';
							$this->mLastSection = 'pre';
						}
						$t = substr( $t, 1 );
					} else {
						# paragraph
						if ( trim( $t ) === '' ) {
							if ( $paragraphStack ) {
								$output .= $paragraphStack.'
';
								$paragraphStack = false;
								$this->mLastSection = 'p';
							} else {
								if ( $this->mLastSection !== 'p' ) {
									$output .= $this->closeParagraph();
									$this->mLastSection = '';
									$paragraphStack = '
';
								} else {
									$paragraphStack = '
';
								}
							}
						} else {
							if ( $paragraphStack ) {
								$output .= $paragraphStack;
								$paragraphStack = false;
								$this->mLastSection = 'p';
							} elseif ( $this->mLastSection !== 'p' ) {
								$output .= $this->closeParagraph().'
';
								$this->mLastSection = 'p';
							}
						}
					}
				}
				wfProfileOut( __METHOD__."-paragraph" );
			}
			# somewhere above we forget to get out of pre block (bug 785)
			if ( $preCloseMatch && $this->mInPre ) {
				$this->mInPre = false;
			}
			if ( $paragraphStack === false ) {
				$output .= $t."\n";
			}
		}
		while ( $prefixLength ) {
			$output .= $this->closeList( $prefix2[$prefixLength-1] );
			--$prefixLength;
		}
		if ( $this->mLastSection != '' ) {
			$output .= 'mLastSection . '>';
			$this->mLastSection = '';
		}

		wfProfileOut( __METHOD__ );
		return $output;
	}

	/**
	 * Split up a string on ':', ignoring any occurences inside tags
	 * to prevent illegal overlapping.
	 *
	 * @param $str String: the string to split
	 * @param &$before String: set to everything before the ':'
	 * @param &$after String: set to everything after the ':'
	 * return String: the position of the ':', or false if none found
	 */
	function findColonNoLinks( $str, &$before, &$after ) {
		wfProfileIn( __METHOD__ );

		$pos = strpos( $str, ':' );
		if ( $pos === false ) {
			# Nothing to find!
			wfProfileOut( __METHOD__ );
			return false;
		}

		$lt = strpos( $str, '<' );
		if ( $lt === false || $lt > $pos ) {
			# Easy; no tag nesting to worry about
			$before = substr( $str, 0, $pos );
			$after = substr( $str, $pos+1 );
			wfProfileOut( __METHOD__ );
			return $pos;
		}

		# Ugly state machine to walk through avoiding tags.
		$state = self::COLON_STATE_TEXT;
		$stack = 0;
		$len = strlen( $str );
		for( $i = 0; $i < $len; $i++ ) {
			$c = $str[$i];

			switch( $state ) {
			# (Using the number is a performance hack for common cases)
			case 0: # self::COLON_STATE_TEXT:
				switch( $c ) {
				case "<":
					# Could be either a  tag or an  tag
					$state = self::COLON_STATE_TAGSTART;
					break;
				case ":":
					if ( $stack == 0 ) {
						# We found it!
						$before = substr( $str, 0, $i );
						$after = substr( $str, $i + 1 );
						wfProfileOut( __METHOD__ );
						return $i;
					}
					# Embedded in a tag; don't break it.
					break;
				default:
					# Skip ahead looking for something interesting
					$colon = strpos( $str, ':', $i );
					if ( $colon === false ) {
						# Nothing else interesting
						wfProfileOut( __METHOD__ );
						return false;
					}
					$lt = strpos( $str, '<', $i );
					if ( $stack === 0 ) {
						if ( $lt === false || $colon < $lt ) {
							# We found it!
							$before = substr( $str, 0, $colon );
							$after = substr( $str, $colon + 1 );
							wfProfileOut( __METHOD__ );
							return $i;
						}
					}
					if ( $lt === false ) {
						# Nothing else interesting to find; abort!
						# We're nested, but there's no close tags left. Abort!
						break 2;
					}
					# Skip ahead to next tag start
					$i = $lt;
					$state = self::COLON_STATE_TAGSTART;
				}
				break;
			case 1: # self::COLON_STATE_TAG:
				# In a 
				switch( $c ) {
				case ">":
					$stack++;
					$state = self::COLON_STATE_TEXT;
					break;
				case "/":
					# Slash may be followed by >?
					$state = self::COLON_STATE_TAGSLASH;
					break;
				default:
					# ignore
				}
				break;
			case 2: # self::COLON_STATE_TAGSTART:
				switch( $c ) {
				case "/":
					$state = self::COLON_STATE_CLOSETAG;
					break;
				case "!":
					$state = self::COLON_STATE_COMMENT;
					break;
				case ">":
					# Illegal early close? This shouldn't happen D:
					$state = self::COLON_STATE_TEXT;
					break;
				default:
					$state = self::COLON_STATE_TAG;
				}
				break;
			case 3: # self::COLON_STATE_CLOSETAG:
				# In a 
				if ( $c === ">" ) {
					$stack--;
					if ( $stack < 0 ) {
						wfDebug( __METHOD__.": Invalid input; too many close tags\n" );
						wfProfileOut( __METHOD__ );
						return false;
					}
					$state = self::COLON_STATE_TEXT;
				}
				break;
			case self::COLON_STATE_TAGSLASH:
				if ( $c === ">" ) {
					# Yes, a self-closed tag 
					$state = self::COLON_STATE_TEXT;
				} else {
					# Probably we're jumping the gun, and this is an attribute
					$state = self::COLON_STATE_TAG;
				}
				break;
			case 5: # self::COLON_STATE_COMMENT:
				if ( $c === "-" ) {
					$state = self::COLON_STATE_COMMENTDASH;
				}
				break;
			case self::COLON_STATE_COMMENTDASH:
				if ( $c === "-" ) {
					$state = self::COLON_STATE_COMMENTDASHDASH;
				} else {
					$state = self::COLON_STATE_COMMENT;
				}
				break;
			case self::COLON_STATE_COMMENTDASHDASH:
				if ( $c === ">" ) {
					$state = self::COLON_STATE_TEXT;
				} else {
					$state = self::COLON_STATE_COMMENT;
				}
				break;
			default:
				throw new MWException( "State machine error in " . __METHOD__ );
			}
		}
		if ( $stack > 0 ) {
			wfDebug( __METHOD__.": Invalid input; not enough close tags (stack $stack, state $state)\n" );
			wfProfileOut( __METHOD__ );
			return false;
		}
		wfProfileOut( __METHOD__ );
		return false;
	}

	/**
	 * Return value of a magic variable (like PAGENAME)
	 *
	 * @private
	 *
	 * @param $index integer
	 * @param $frame PPFrame
	 */
	function getVariableValue( $index, $frame=false ) {
		global $wgContLang, $wgSitename, $wgServer;
		global $wgArticlePath, $wgScriptPath, $wgStylePath;

		/**
		 * Some of these require message or data lookups and can be
		 * expensive to check many times.
		 */
		if ( wfRunHooks( 'ParserGetVariableValueVarCache', array( &$this, &$this->mVarCache ) ) ) {
			if ( isset( $this->mVarCache[$index] ) ) {
				return $this->mVarCache[$index];
			}
		}

		$ts = wfTimestamp( TS_UNIX, $this->mOptions->getTimestamp() );
		wfRunHooks( 'ParserGetVariableValueTs', array( &$this, &$ts ) );

		# Use the time zone
		global $wgLocaltimezone;
		if ( isset( $wgLocaltimezone ) ) {
			$oldtz = date_default_timezone_get();
			date_default_timezone_set( $wgLocaltimezone );
		}

		$localTimestamp = date( 'YmdHis', $ts );
		$localMonth = date( 'm', $ts );
		$localMonth1 = date( 'n', $ts );
		$localMonthName = date( 'n', $ts );
		$localDay = date( 'j', $ts );
		$localDay2 = date( 'd', $ts );
		$localDayOfWeek = date( 'w', $ts );
		$localWeek = date( 'W', $ts );
		$localYear = date( 'Y', $ts );
		$localHour = date( 'H', $ts );
		if ( isset( $wgLocaltimezone ) ) {
			date_default_timezone_set( $oldtz );
		}

		switch ( $index ) {
			case 'currentmonth':
				$value = $wgContLang->formatNum( gmdate( 'm', $ts ) );
				break;
			case 'currentmonth1':
				$value = $wgContLang->formatNum( gmdate( 'n', $ts ) );
				break;
			case 'currentmonthname':
				$value = $wgContLang->getMonthName( gmdate( 'n', $ts ) );
				break;
			case 'currentmonthnamegen':
				$value = $wgContLang->getMonthNameGen( gmdate( 'n', $ts ) );
				break;
			case 'currentmonthabbrev':
				$value = $wgContLang->getMonthAbbreviation( gmdate( 'n', $ts ) );
				break;
			case 'currentday':
				$value = $wgContLang->formatNum( gmdate( 'j', $ts ) );
				break;
			case 'currentday2':
				$value = $wgContLang->formatNum( gmdate( 'd', $ts ) );
				break;
			case 'localmonth':
				$value = $wgContLang->formatNum( $localMonth );
				break;
			case 'localmonth1':
				$value = $wgContLang->formatNum( $localMonth1 );
				break;
			case 'localmonthname':
				$value = $wgContLang->getMonthName( $localMonthName );
				break;
			case 'localmonthnamegen':
				$value = $wgContLang->getMonthNameGen( $localMonthName );
				break;
			case 'localmonthabbrev':
				$value = $wgContLang->getMonthAbbreviation( $localMonthName );
				break;
			case 'localday':
				$value = $wgContLang->formatNum( $localDay );
				break;
			case 'localday2':
				$value = $wgContLang->formatNum( $localDay2 );
				break;
			case 'pagename':
				$value = wfEscapeWikiText( $this->mTitle->getText() );
				break;
			case 'pagenamee':
				$value = wfEscapeWikiText( $this->mTitle->getPartialURL() );
				break;
			case 'fullpagename':
				$value = wfEscapeWikiText( $this->mTitle->getPrefixedText() );
				break;
			case 'fullpagenamee':
				$value = wfEscapeWikiText( $this->mTitle->getPrefixedURL() );
				break;
			case 'subpagename':
				$value = wfEscapeWikiText( $this->mTitle->getSubpageText() );
				break;
			case 'subpagenamee':
				$value = wfEscapeWikiText( $this->mTitle->getSubpageUrlForm() );
				break;
			case 'basepagename':
				$value = wfEscapeWikiText( $this->mTitle->getBaseText() );
				break;
			case 'basepagenamee':
				$value = wfEscapeWikiText( wfUrlEncode( str_replace( ' ', '_', $this->mTitle->getBaseText() ) ) );
				break;
			case 'talkpagename':
				if ( $this->mTitle->canTalk() ) {
					$talkPage = $this->mTitle->getTalkPage();
					$value = wfEscapeWikiText( $talkPage->getPrefixedText() );
				} else {
					$value = '';
				}
				break;
			case 'talkpagenamee':
				if ( $this->mTitle->canTalk() ) {
					$talkPage = $this->mTitle->getTalkPage();
					$value = wfEscapeWikiText( $talkPage->getPrefixedUrl() );
				} else {
					$value = '';
				}
				break;
			case 'subjectpagename':
				$subjPage = $this->mTitle->getSubjectPage();
				$value = wfEscapeWikiText( $subjPage->getPrefixedText() );
				break;
			case 'subjectpagenamee':
				$subjPage = $this->mTitle->getSubjectPage();
				$value = wfEscapeWikiText( $subjPage->getPrefixedUrl() );
				break;
			case 'revisionid':
				# Let the edit saving system know we should parse the page
				# *after* a revision ID has been assigned.
				$this->mOutput->setFlag( 'vary-revision' );
				wfDebug( __METHOD__ . ": {{REVISIONID}} used, setting vary-revision...\n" );
				$value = $this->mRevisionId;
				break;
			case 'revisionday':
				# Let the edit saving system know we should parse the page
				# *after* a revision ID has been assigned. This is for null edits.
				$this->mOutput->setFlag( 'vary-revision' );
				wfDebug( __METHOD__ . ": {{REVISIONDAY}} used, setting vary-revision...\n" );
				$value = intval( substr( $this->getRevisionTimestamp(), 6, 2 ) );
				break;
			case 'revisionday2':
				# Let the edit saving system know we should parse the page
				# *after* a revision ID has been assigned. This is for null edits.
				$this->mOutput->setFlag( 'vary-revision' );
				wfDebug( __METHOD__ . ": {{REVISIONDAY2}} used, setting vary-revision...\n" );
				$value = substr( $this->getRevisionTimestamp(), 6, 2 );
				break;
			case 'revisionmonth':
				# Let the edit saving system know we should parse the page
				# *after* a revision ID has been assigned. This is for null edits.
				$this->mOutput->setFlag( 'vary-revision' );
				wfDebug( __METHOD__ . ": {{REVISIONMONTH}} used, setting vary-revision...\n" );
				$value = substr( $this->getRevisionTimestamp(), 4, 2 );
				break;
			case 'revisionmonth1':
				# Let the edit saving system know we should parse the page
				# *after* a revision ID has been assigned. This is for null edits.
				$this->mOutput->setFlag( 'vary-revision' );
				wfDebug( __METHOD__ . ": {{REVISIONMONTH1}} used, setting vary-revision...\n" );
				$value = intval( substr( $this->getRevisionTimestamp(), 4, 2 ) );
				break;
			case 'revisionyear':
				# Let the edit saving system know we should parse the page
				# *after* a revision ID has been assigned. This is for null edits.
				$this->mOutput->setFlag( 'vary-revision' );
				wfDebug( __METHOD__ . ": {{REVISIONYEAR}} used, setting vary-revision...\n" );
				$value = substr( $this->getRevisionTimestamp(), 0, 4 );
				break;
			case 'revisiontimestamp':
				# Let the edit saving system know we should parse the page
				# *after* a revision ID has been assigned. This is for null edits.
				$this->mOutput->setFlag( 'vary-revision' );
				wfDebug( __METHOD__ . ": {{REVISIONTIMESTAMP}} used, setting vary-revision...\n" );
				$value = $this->getRevisionTimestamp();
				break;
			case 'revisionuser':
				# Let the edit saving system know we should parse the page
				# *after* a revision ID has been assigned. This is for null edits.
				$this->mOutput->setFlag( 'vary-revision' );
				wfDebug( __METHOD__ . ": {{REVISIONUSER}} used, setting vary-revision...\n" );
				$value = $this->getRevisionUser();
				break;
			case 'namespace':
				$value = str_replace( '_',' ',$wgContLang->getNsText( $this->mTitle->getNamespace() ) );
				break;
			case 'namespacee':
				$value = wfUrlencode( $wgContLang->getNsText( $this->mTitle->getNamespace() ) );
				break;
			case 'talkspace':
				$value = $this->mTitle->canTalk() ? str_replace( '_',' ',$this->mTitle->getTalkNsText() ) : '';
				break;
			case 'talkspacee':
				$value = $this->mTitle->canTalk() ? wfUrlencode( $this->mTitle->getTalkNsText() ) : '';
				break;
			case 'subjectspace':
				$value = $this->mTitle->getSubjectNsText();
				break;
			case 'subjectspacee':
				$value = ( wfUrlencode( $this->mTitle->getSubjectNsText() ) );
				break;
			case 'currentdayname':
				$value = $wgContLang->getWeekdayName( gmdate( 'w', $ts ) + 1 );
				break;
			case 'currentyear':
				$value = $wgContLang->formatNum( gmdate( 'Y', $ts ), true );
				break;
			case 'currenttime':
				$value = $wgContLang->time( wfTimestamp( TS_MW, $ts ), false, false );
				break;
			case 'currenthour':
				$value = $wgContLang->formatNum( gmdate( 'H', $ts ), true );
				break;
			case 'currentweek':
				# @bug 4594 PHP5 has it zero padded, PHP4 does not, cast to
				# int to remove the padding
				$value = $wgContLang->formatNum( (int)gmdate( 'W', $ts ) );
				break;
			case 'currentdow':
				$value = $wgContLang->formatNum( gmdate( 'w', $ts ) );
				break;
			case 'localdayname':
				$value = $wgContLang->getWeekdayName( $localDayOfWeek + 1 );
				break;
			case 'localyear':
				$value = $wgContLang->formatNum( $localYear, true );
				break;
			case 'localtime':
				$value = $wgContLang->time( $localTimestamp, false, false );
				break;
			case 'localhour':
				$value = $wgContLang->formatNum( $localHour, true );
				break;
			case 'localweek':
				# @bug 4594 PHP5 has it zero padded, PHP4 does not, cast to
				# int to remove the padding
				$value = $wgContLang->formatNum( (int)$localWeek );
				break;
			case 'localdow':
				$value = $wgContLang->formatNum( $localDayOfWeek );
				break;
			case 'numberofarticles':
				$value = $wgContLang->formatNum( SiteStats::articles() );
				break;
			case 'numberoffiles':
				$value = $wgContLang->formatNum( SiteStats::images() );
				break;
			case 'numberofusers':
				$value = $wgContLang->formatNum( SiteStats::users() );
				break;
			case 'numberofactiveusers':
				$value = $wgContLang->formatNum( SiteStats::activeUsers() );
				break;
			case 'numberofpages':
				$value = $wgContLang->formatNum( SiteStats::pages() );
				break;
			case 'numberofadmins':
				$value = $wgContLang->formatNum( SiteStats::numberingroup( 'sysop' ) );
				break;
			case 'numberofedits':
				$value = $wgContLang->formatNum( SiteStats::edits() );
				break;
			case 'numberofviews':
				$value = $wgContLang->formatNum( SiteStats::views() );
				break;
			case 'currenttimestamp':
				$value = wfTimestamp( TS_MW, $ts );
				break;
			case 'localtimestamp':
				$value = $localTimestamp;
				break;
			case 'currentversion':
				$value = SpecialVersion::getVersion();
				break;
			case 'articlepath':
				return $wgArticlePath;
			case 'sitename':
				return $wgSitename;
			case 'server':
				return $wgServer;
			case 'servername':
				$serverParts = wfParseUrl( $wgServer );
				return $serverParts && isset( $serverParts['host'] ) ? $serverParts['host'] : $wgServer;
			case 'scriptpath':
				return $wgScriptPath;
			case 'stylepath':
				return $wgStylePath;
			case 'directionmark':
				return $wgContLang->getDirMark();
			case 'contentlanguage':
				global $wgLanguageCode;
				return $wgLanguageCode;
			default:
				$ret = null;
				if ( wfRunHooks( 'ParserGetVariableValueSwitch', array( &$this, &$this->mVarCache, &$index, &$ret, &$frame ) ) ) {
					return $ret;
				} else {
					return null;
				}
		}

		if ( $index )
			$this->mVarCache[$index] = $value;

		return $value;
	}

	/**
	 * initialise the magic variables (like CURRENTMONTHNAME) and substitution modifiers
	 *
	 * @private
	 */
	function initialiseVariables() {
		wfProfileIn( __METHOD__ );
		$variableIDs = MagicWord::getVariableIDs();
		$substIDs = MagicWord::getSubstIDs();

		$this->mVariables = new MagicWordArray( $variableIDs );
		$this->mSubstWords = new MagicWordArray( $substIDs );
		wfProfileOut( __METHOD__ );
	}

	/**
	 * Preprocess some wikitext and return the document tree.
	 * This is the ghost of replace_variables().
	 *
	 * @param $text String: The text to parse
	 * @param $flags Integer: bitwise combination of:
	 *          self::PTD_FOR_INCLUSION    Handle / as if the text is being
	 *                                     included. Default is to assume a direct page view.
	 *
	 * The generated DOM tree must depend only on the input text and the flags.
	 * The DOM tree must be the same in OT_HTML and OT_WIKI mode, to avoid a regression of bug 4899.
	 *
	 * Any flag added to the $flags parameter here, or any other parameter liable to cause a
	 * change in the DOM tree for a given text, must be passed through the section identifier
	 * in the section edit link and thus back to extractSections().
	 *
	 * The output of this function is currently only cached in process memory, but a persistent
	 * cache may be implemented at a later date which takes further advantage of these strict
	 * dependency requirements.
	 *
	 * @private
	 *
	 * @return PPNode
	 */
	function preprocessToDom( $text, $flags = 0 ) {
		$dom = $this->getPreprocessor()->preprocessToObj( $text, $flags );
		return $dom;
	}

	/**
	 * Return a three-element array: leading whitespace, string contents, trailing whitespace
	 *
	 * @return array
	 */
	public static function splitWhitespace( $s ) {
		$ltrimmed = ltrim( $s );
		$w1 = substr( $s, 0, strlen( $s ) - strlen( $ltrimmed ) );
		$trimmed = rtrim( $ltrimmed );
		$diff = strlen( $ltrimmed ) - strlen( $trimmed );
		if ( $diff > 0 ) {
			$w2 = substr( $ltrimmed, -$diff );
		} else {
			$w2 = '';
		}
		return array( $w1, $trimmed, $w2 );
	}

	/**
	 * Replace magic variables, templates, and template arguments
	 * with the appropriate text. Templates are substituted recursively,
	 * taking care to avoid infinite loops.
	 *
	 * Note that the substitution depends on value of $mOutputType:
	 *  self::OT_WIKI: only {{subst:}} templates
	 *  self::OT_PREPROCESS: templates but not extension tags
	 *  self::OT_HTML: all templates and extension tags
	 *
	 * @param $text String: the text to transform
	 * @param $frame PPFrame Object describing the arguments passed to the template.
	 *        Arguments may also be provided as an associative array, as was the usual case before MW1.12.
	 *        Providing arguments this way may be useful for extensions wishing to perform variable replacement explicitly.
	 * @param $argsOnly Boolean: only do argument (triple-brace) expansion, not double-brace expansion
	 * @private
	 *
	 * @return string
	 */
	function replaceVariables( $text, $frame = false, $argsOnly = false ) {
		# Is there any text? Also, Prevent too big inclusions!
		if ( strlen( $text ) < 1 || strlen( $text ) > $this->mOptions->getMaxIncludeSize() ) {
			return $text;
		}
		wfProfileIn( __METHOD__ );

		if ( $frame === false ) {
			$frame = $this->getPreprocessor()->newFrame();
		} elseif ( !( $frame instanceof PPFrame ) ) {
			wfDebug( __METHOD__." called using plain parameters instead of a PPFrame instance. Creating custom frame.\n" );
			$frame = $this->getPreprocessor()->newCustomFrame( $frame );
		}

		$dom = $this->preprocessToDom( $text );
		$flags = $argsOnly ? PPFrame::NO_TEMPLATES : 0;
		$text = $frame->expand( $dom, $flags );

		wfProfileOut( __METHOD__ );
		return $text;
	}

	/**
	 * Clean up argument array - refactored in 1.9 so parserfunctions can use it, too.
	 *
	 * @return array
	 */
	static function createAssocArgs( $args ) {
		$assocArgs = array();
		$index = 1;
		foreach ( $args as $arg ) {
			$eqpos = strpos( $arg, '=' );
			if ( $eqpos === false ) {
				$assocArgs[$index++] = $arg;
			} else {
				$name = trim( substr( $arg, 0, $eqpos ) );
				$value = trim( substr( $arg, $eqpos+1 ) );
				if ( $value === false ) {
					$value = '';
				}
				if ( $name !== false ) {
					$assocArgs[$name] = $value;
				}
			}
		}

		return $assocArgs;
	}

	/**
	 * Warn the user when a parser limitation is reached
	 * Will warn at most once the user per limitation type
	 *
	 * @param $limitationType String: should be one of:
	 *   'expensive-parserfunction' (corresponding messages:
	 *       'expensive-parserfunction-warning',
	 *       'expensive-parserfunction-category')
	 *   'post-expand-template-argument' (corresponding messages:
	 *       'post-expand-template-argument-warning',
	 *       'post-expand-template-argument-category')
	 *   'post-expand-template-inclusion' (corresponding messages:
	 *       'post-expand-template-inclusion-warning',
	 *       'post-expand-template-inclusion-category')
	 * @param $current Current value
	 * @param $max Maximum allowed, when an explicit limit has been
	 *	 exceeded, provide the values (optional)
	 */
	function limitationWarn( $limitationType, $current=null, $max=null) {
		# does no harm if $current and $max are present but are unnecessary for the message
		$warning = wfMsgExt( "$limitationType-warning", array( 'parsemag', 'escape' ), $current, $max );
		$this->mOutput->addWarning( $warning );
		$this->addTrackingCategory( "$limitationType-category" );
	}

	/**
	 * Return the text of a template, after recursively
	 * replacing any variables or templates within the template.
	 *
	 * @param $piece Array: the parts of the template
	 *  $piece['title']: the title, i.e. the part before the |
	 *  $piece['parts']: the parameter array
	 *  $piece['lineStart']: whether the brace was at the start of a line
	 * @param $frame PPFrame The current frame, contains template arguments
	 * @return String: the text of the template
	 * @private
	 */
	function braceSubstitution( $piece, $frame ) {
		global $wgContLang, $wgNonincludableNamespaces;
		wfProfileIn( __METHOD__ );
		wfProfileIn( __METHOD__.'-setup' );

		# Flags
		$found = false;             # $text has been filled
		$nowiki = false;            # wiki markup in $text should be escaped
		$isHTML = false;            # $text is HTML, armour it against wikitext transformation
		$forceRawInterwiki = false; # Force interwiki transclusion to be done in raw mode not rendered
		$isChildObj = false;        # $text is a DOM node needing expansion in a child frame
		$isLocalObj = false;        # $text is a DOM node needing expansion in the current frame

		# Title object, where $text came from
		$title = false;

		# $part1 is the bit before the first |, and must contain only title characters.
		# Various prefixes will be stripped from it later.
		$titleWithSpaces = $frame->expand( $piece['title'] );
		$part1 = trim( $titleWithSpaces );
		$titleText = false;

		# Original title text preserved for various purposes
		$originalTitle = $part1;

		# $args is a list of argument nodes, starting from index 0, not including $part1
		# @todo FIXME: If piece['parts'] is null then the call to getLength() below won't work b/c this $args isn't an object
		$args = ( null == $piece['parts'] ) ? array() : $piece['parts'];
		wfProfileOut( __METHOD__.'-setup' );
		wfProfileIn( __METHOD__."-title-$originalTitle" );

		# SUBST
		wfProfileIn( __METHOD__.'-modifiers' );
		if ( !$found ) {

			$substMatch = $this->mSubstWords->matchStartAndRemove( $part1 );

			# Possibilities for substMatch: "subst", "safesubst" or FALSE
			# Decide whether to expand template or keep wikitext as-is.
			if ( $this->ot['wiki'] ) {
				if ( $substMatch === false ) {
					$literal = true;  # literal when in PST with no prefix
				} else {
					$literal = false; # expand when in PST with subst: or safesubst:
				}
			} else {
				if ( $substMatch == 'subst' ) {
					$literal = true;  # literal when not in PST with plain subst:
				} else {
					$literal = false; # expand when not in PST with safesubst: or no prefix
				}
			}
			if ( $literal ) {
				$text = $frame->virtualBracketedImplode( '{{', '|', '}}', $titleWithSpaces, $args );
				$isLocalObj = true;
				$found = true;
			}
		}

		# Variables
		if ( !$found && $args->getLength() == 0 ) {
			$id = $this->mVariables->matchStartToEnd( $part1 );
			if ( $id !== false ) {
				$text = $this->getVariableValue( $id, $frame );
				if ( MagicWord::getCacheTTL( $id ) > -1 ) {
					$this->mOutput->updateCacheExpiry( MagicWord::getCacheTTL( $id ) );
				}
				$found = true;
			}
		}

		# MSG, MSGNW and RAW
		if ( !$found ) {
			# Check for MSGNW:
			$mwMsgnw = MagicWord::get( 'msgnw' );
			if ( $mwMsgnw->matchStartAndRemove( $part1 ) ) {
				$nowiki = true;
			} else {
				# Remove obsolete MSG:
				$mwMsg = MagicWord::get( 'msg' );
				$mwMsg->matchStartAndRemove( $part1 );
			}

			# Check for RAW:
			$mwRaw = MagicWord::get( 'raw' );
			if ( $mwRaw->matchStartAndRemove( $part1 ) ) {
				$forceRawInterwiki = true;
			}
		}
		wfProfileOut( __METHOD__.'-modifiers' );

		# Parser functions
		if ( !$found ) {
			wfProfileIn( __METHOD__ . '-pfunc' );

			$colonPos = strpos( $part1, ':' );
			if ( $colonPos !== false ) {
				# Case sensitive functions
				$function = substr( $part1, 0, $colonPos );
				if ( isset( $this->mFunctionSynonyms[1][$function] ) ) {
					$function = $this->mFunctionSynonyms[1][$function];
				} else {
					# Case insensitive functions
					$function = $wgContLang->lc( $function );
					if ( isset( $this->mFunctionSynonyms[0][$function] ) ) {
						$function = $this->mFunctionSynonyms[0][$function];
					} else {
						$function = false;
					}
				}
				if ( $function ) {
					list( $callback, $flags ) = $this->mFunctionHooks[$function];
					$initialArgs = array( &$this );
					$funcArgs = array( trim( substr( $part1, $colonPos + 1 ) ) );
					if ( $flags & SFH_OBJECT_ARGS ) {
						# Add a frame parameter, and pass the arguments as an array
						$allArgs = $initialArgs;
						$allArgs[] = $frame;
						for ( $i = 0; $i < $args->getLength(); $i++ ) {
							$funcArgs[] = $args->item( $i );
						}
						$allArgs[] = $funcArgs;
					} else {
						# Convert arguments to plain text
						for ( $i = 0; $i < $args->getLength(); $i++ ) {
							$funcArgs[] = trim( $frame->expand( $args->item( $i ) ) );
						}
						$allArgs = array_merge( $initialArgs, $funcArgs );
					}

					# Workaround for PHP bug 35229 and similar
					if ( !is_callable( $callback ) ) {
						wfProfileOut( __METHOD__ . '-pfunc' );
						wfProfileOut( __METHOD__ );
						throw new MWException( "Tag hook for $function is not callable\n" );
					}
					$result = call_user_func_array( $callback, $allArgs );
					$found = true;
					$noparse = true;
					$preprocessFlags = 0;

					if ( is_array( $result ) ) {
						if ( isset( $result[0] ) ) {
							$text = $result[0];
							unset( $result[0] );
						}

						# Extract flags into the local scope
						# This allows callers to set flags such as nowiki, found, etc.
						extract( $result );
					} else {
						$text = $result;
					}
					if ( !$noparse ) {
						$text = $this->preprocessToDom( $text, $preprocessFlags );
						$isChildObj = true;
					}
				}
			}
			wfProfileOut( __METHOD__ . '-pfunc' );
		}

		# Finish mangling title and then check for loops.
		# Set $title to a Title object and $titleText to the PDBK
		if ( !$found ) {
			$ns = NS_TEMPLATE;
			# Split the title into page and subpage
			$subpage = '';
			$part1 = $this->maybeDoSubpageLink( $part1, $subpage );
			if ( $subpage !== '' ) {
				$ns = $this->mTitle->getNamespace();
			}
			$title = Title::newFromText( $part1, $ns );
			if ( $title ) {
				$titleText = $title->getPrefixedText();
				# Check for language variants if the template is not found
				if ( $wgContLang->hasVariants() && $title->getArticleID() == 0 ) {
					$wgContLang->findVariantLink( $part1, $title, true );
				}
				# Do recursion depth check
				$limit = $this->mOptions->getMaxTemplateDepth();
				if ( $frame->depth >= $limit ) {
					$found = true;
					$text = ''
						. wfMsgForContent( 'parser-template-recursion-depth-warning', $limit )
						. '';
				}
			}
		}

		# Load from database
		if ( !$found && $title ) {
			wfProfileIn( __METHOD__ . '-loadtpl' );
			if ( !$title->isExternal() ) {
				if ( $title->getNamespace() == NS_SPECIAL
					&& $this->mOptions->getAllowSpecialInclusion()
					&& $this->ot['html'] )
				{
					$text = SpecialPageFactory::capturePath( $title );
					if ( is_string( $text ) ) {
						$found = true;
						$isHTML = true;
						$this->disableCache();
					}
				} elseif ( $wgNonincludableNamespaces && in_array( $title->getNamespace(), $wgNonincludableNamespaces ) ) {
					$found = false; # access denied
					wfDebug( __METHOD__.": template inclusion denied for " . $title->getPrefixedDBkey() );
				} else {
					list( $text, $title ) = $this->getTemplateDom( $title );
					if ( $text !== false ) {
						$found = true;
						$isChildObj = true;
					}
				}

				# If the title is valid but undisplayable, make a link to it
				if ( !$found && ( $this->ot['html'] || $this->ot['pre'] ) ) {
					$text = "[[:$titleText]]";
					$found = true;
				}
			} elseif ( $title->isTrans() ) {
				# Interwiki transclusion
				if ( $this->ot['html'] && !$forceRawInterwiki ) {
					$text = $this->interwikiTransclude( $title, 'render' );
					$isHTML = true;
				} else {
					$text = $this->interwikiTransclude( $title, 'raw' );
					# Preprocess it like a template
					$text = $this->preprocessToDom( $text, self::PTD_FOR_INCLUSION );
					$isChildObj = true;
				}
				$found = true;
			}

			# Do infinite loop check
			# This has to be done after redirect resolution to avoid infinite loops via redirects
			if ( !$frame->loopCheck( $title ) ) {
				$found = true;
				$text = '' . wfMsgForContent( 'parser-template-loop-warning', $titleText ) . '';
				wfDebug( __METHOD__.": template loop broken at '$titleText'\n" );
			}
			wfProfileOut( __METHOD__ . '-loadtpl' );
		}

		# If we haven't found text to substitute by now, we're done
		# Recover the source wikitext and return it
		if ( !$found ) {
			$text = $frame->virtualBracketedImplode( '{{', '|', '}}', $titleWithSpaces, $args );
			wfProfileOut( __METHOD__."-title-$originalTitle" );
			wfProfileOut( __METHOD__ );
			return array( 'object' => $text );
		}

		# Expand DOM-style return values in a child frame
		if ( $isChildObj ) {
			# Clean up argument array
			$newFrame = $frame->newChild( $args, $title );

			if ( $nowiki ) {
				$text = $newFrame->expand( $text, PPFrame::RECOVER_ORIG );
			} elseif ( $titleText !== false && $newFrame->isEmpty() ) {
				# Expansion is eligible for the empty-frame cache
				if ( isset( $this->mTplExpandCache[$titleText] ) ) {
					$text = $this->mTplExpandCache[$titleText];
				} else {
					$text = $newFrame->expand( $text );
					$this->mTplExpandCache[$titleText] = $text;
				}
			} else {
				# Uncached expansion
				$text = $newFrame->expand( $text );
			}
		}
		if ( $isLocalObj && $nowiki ) {
			$text = $frame->expand( $text, PPFrame::RECOVER_ORIG );
			$isLocalObj = false;
		}

		# Replace raw HTML by a placeholder
		# Add a blank line preceding, to prevent it from mucking up
		# immediately preceding headings
		if ( $isHTML ) {
			$text = "\n\n" . $this->insertStripItem( $text );
		} elseif ( $nowiki && ( $this->ot['html'] || $this->ot['pre'] ) ) {
			# Escape nowiki-style return values
			$text = wfEscapeWikiText( $text );
		} elseif ( is_string( $text )
			&& !$piece['lineStart']
			&& preg_match( '/^(?:{\\||:|;|#|\*)/', $text ) )
		{
			# Bug 529: if the template begins with a table or block-level
			# element, it should be treated as beginning a new line.
			# This behaviour is somewhat controversial.
			$text = "\n" . $text;
		}

		if ( is_string( $text ) && !$this->incrementIncludeSize( 'post-expand', strlen( $text ) ) ) {
			# Error, oversize inclusion
			if ( $titleText !== false ) {
				# Make a working, properly escaped link if possible (bug 23588)
				$text = "[[:$titleText]]";
			} else {
				# This will probably not be a working link, but at least it may
				# provide some hint of where the problem is
				preg_replace( '/^:/', '', $originalTitle );
				$text = "[[:$originalTitle]]";
			}
			$text .= $this->insertStripItem( '' );
			$this->limitationWarn( 'post-expand-template-inclusion' );
		}

		if ( $isLocalObj ) {
			$ret = array( 'object' => $text );
		} else {
			$ret = array( 'text' => $text );
		}

		wfProfileOut( __METHOD__."-title-$originalTitle" );
		wfProfileOut( __METHOD__ );
		return $ret;
	}

	/**
	 * Get the semi-parsed DOM representation of a template with a given title,
	 * and its redirect destination title. Cached.
	 *
	 * @return array
	 */
	function getTemplateDom( $title ) {
		$cacheTitle = $title;
		$titleText = $title->getPrefixedDBkey();

		if ( isset( $this->mTplRedirCache[$titleText] ) ) {
			list( $ns, $dbk ) = $this->mTplRedirCache[$titleText];
			$title = Title::makeTitle( $ns, $dbk );
			$titleText = $title->getPrefixedDBkey();
		}
		if ( isset( $this->mTplDomCache[$titleText] ) ) {
			return array( $this->mTplDomCache[$titleText], $title );
		}

		# Cache miss, go to the database
		list( $text, $title ) = $this->fetchTemplateAndTitle( $title );

		if ( $text === false ) {
			$this->mTplDomCache[$titleText] = false;
			return array( false, $title );
		}

		$dom = $this->preprocessToDom( $text, self::PTD_FOR_INCLUSION );
		$this->mTplDomCache[ $titleText ] = $dom;

		if ( !$title->equals( $cacheTitle ) ) {
			$this->mTplRedirCache[$cacheTitle->getPrefixedDBkey()] =
				array( $title->getNamespace(), $cdb = $title->getDBkey() );
		}

		return array( $dom, $title );
	}

	/**
	 * Fetch the unparsed text of a template and register a reference to it.
	 * @param Title $title
	 * @return Array ( string or false, Title )
	 */
	function fetchTemplateAndTitle( $title ) {
		$templateCb = $this->mOptions->getTemplateCallback(); # Defaults to Parser::statelessFetchTemplate()
		$stuff = call_user_func( $templateCb, $title, $this );
		$text = $stuff['text'];
		$finalTitle = isset( $stuff['finalTitle'] ) ? $stuff['finalTitle'] : $title;
		if ( isset( $stuff['deps'] ) ) {
			foreach ( $stuff['deps'] as $dep ) {
				$this->mOutput->addTemplate( $dep['title'], $dep['page_id'], $dep['rev_id'] );
			}
		}
		return array( $text, $finalTitle );
	}

	/**
	 * Fetch the unparsed text of a template and register a reference to it.
	 * @param Title $title
	 * @return mixed string or false
	 */
	function fetchTemplate( $title ) {
		$rv = $this->fetchTemplateAndTitle( $title );
		return $rv[0];
	}

	/**
	 * Static function to get a template
	 * Can be overridden via ParserOptions::setTemplateCallback().
	 *
	 * @return array
	 */
	static function statelessFetchTemplate( $title, $parser = false ) {
		$text = $skip = false;
		$finalTitle = $title;
		$deps = array();

		# Loop to fetch the article, with up to 1 redirect
		for ( $i = 0; $i < 2 && is_object( $title ); $i++ ) {
			# Give extensions a chance to select the revision instead
			$id = false; # Assume current
			wfRunHooks( 'BeforeParserFetchTemplateAndtitle',
				array( $parser, $title, &$skip, &$id ) );

			if ( $skip ) {
				$text = false;
				$deps[] = array(
					'title' 	=> $title,
					'page_id' 	=> $title->getArticleID(),
					'rev_id' 	=> null
				);
				break;
			}
			# Get the revision
			$rev = $id
				? Revision::newFromId( $id )
				: Revision::newFromTitle( $title );
			$rev_id = $rev ? $rev->getId() : 0;
			# If there is no current revision, there is no page
			if ( $id === false && !$rev ) {
				$linkCache = LinkCache::singleton();
				$linkCache->addBadLinkObj( $title );
			}

			$deps[] = array(
				'title' 	=> $title,
				'page_id' 	=> $title->getArticleID(),
				'rev_id' 	=> $rev_id );
			if ( $rev && !$title->equals( $rev->getTitle() ) ) {
				# We fetched a rev from a different title; register it too...
				$deps[] = array(
					'title' 	=> $rev->getTitle(),
					'page_id' 	=> $rev->getPage(),
					'rev_id' 	=> $rev_id );
			}

			if ( $rev ) {
				$text = $rev->getText();
			} elseif ( $title->getNamespace() == NS_MEDIAWIKI ) {
				global $wgContLang;
				$message = wfMessage( $wgContLang->lcfirst( $title->getText() ) )->inContentLanguage();
				if ( !$message->exists() ) {
					$text = false;
					break;
				}
				$text = $message->plain();
			} else {
				break;
			}
			if ( $text === false ) {
				break;
			}
			# Redirect?
			$finalTitle = $title;
			$title = Title::newFromRedirect( $text );
		}
		return array(
			'text' => $text,
			'finalTitle' => $finalTitle,
			'deps' => $deps );
	}

	/**
	 * Fetch a file and its title and register a reference to it.
	 * @param Title $title
	 * @param string $time MW timestamp
	 * @param string $sha1 base 36 SHA-1
	 * @return mixed File or false
	 */
	function fetchFile( $title, $time = false, $sha1 = false ) {
		$res = $this->fetchFileAndTitle( $title, $time, $sha1 );
		return $res[0];
	}

	/**
	 * Fetch a file and its title and register a reference to it.
	 * @param Title $title
	 * @param string $time MW timestamp
	 * @param string $sha1 base 36 SHA-1
	 * @return Array ( File or false, Title of file )
	 */
	function fetchFileAndTitle( $title, $time = false, $sha1 = false ) {
		if ( $time === '0' ) {
			$file = false; // broken thumbnail forced by hook
		} elseif ( $sha1 ) { // get by (sha1,timestamp)
			$file = RepoGroup::singleton()->findFileFromKey( $sha1, array( 'time' => $time ) );
		} else { // get by (name,timestamp)
			$file = wfFindFile( $title, array( 'time' => $time ) );
		}
		$time = $file ? $file->getTimestamp() : false;
		$sha1 = $file ? $file->getSha1() : false;
		# Register the file as a dependency...
		$this->mOutput->addImage( $title->getDBkey(), $time, $sha1 );
		if ( $file && !$title->equals( $file->getTitle() ) ) {
			# Update fetched file title
			$title = $file->getTitle();
			if ( is_null( $file->getRedirectedTitle() ) ) {
				# This file was not a redirect, but the title does not match.
				# Register under the new name because otherwise the link will
				# get lost.
				$this->mOutput->addImage( $title->getDBkey(), $time, $sha1 );
			}
		}
		return array( $file, $title );
	}

	/**
	 * Transclude an interwiki link.
	 *
	 * @param $title Title
	 * @param $action
	 *
	 * @return string
	 */
	function interwikiTransclude( $title, $action ) {
		global $wgEnableScaryTranscluding;

		if ( !$wgEnableScaryTranscluding ) {
			return wfMsgForContent('scarytranscludedisabled');
		}

		$url = $title->getFullUrl( "action=$action" );

		if ( strlen( $url ) > 255 ) {
			return wfMsgForContent( 'scarytranscludetoolong' );
		}
		return $this->fetchScaryTemplateMaybeFromCache( $url );
	}

	/**
	 * @param $url string
	 * @return Mixed|String
	 */
	function fetchScaryTemplateMaybeFromCache( $url ) {
		global $wgTranscludeCacheExpiry;
		$dbr = wfGetDB( DB_SLAVE );
		$tsCond = $dbr->timestamp( time() - $wgTranscludeCacheExpiry );
		$obj = $dbr->selectRow( 'transcache', array('tc_time', 'tc_contents' ),
				array( 'tc_url' => $url, "tc_time >= " . $dbr->addQuotes( $tsCond ) ) );
		if ( $obj ) {
			return $obj->tc_contents;
		}

		$text = Http::get( $url );
		if ( !$text ) {
			return wfMsgForContent( 'scarytranscludefailed', $url );
		}

		$dbw = wfGetDB( DB_MASTER );
		$dbw->replace( 'transcache', array('tc_url'), array(
			'tc_url' => $url,
			'tc_time' => $dbw->timestamp( time() ),
			'tc_contents' => $text)
		);
		return $text;
	}

	/**
	 * Triple brace replacement -- used for template arguments
	 * @private
	 *
	 * @param $peice array
	 * @param $frame PPFrame
	 *
	 * @return array
	 */
	function argSubstitution( $piece, $frame ) {
		wfProfileIn( __METHOD__ );

		$error = false;
		$parts = $piece['parts'];
		$nameWithSpaces = $frame->expand( $piece['title'] );
		$argName = trim( $nameWithSpaces );
		$object = false;
		$text = $frame->getArgument( $argName );
		if (  $text === false && $parts->getLength() > 0
		  && (
			$this->ot['html']
			|| $this->ot['pre']
			|| ( $this->ot['wiki'] && $frame->isTemplate() )
		  )
		) {
			# No match in frame, use the supplied default
			$object = $parts->item( 0 )->getChildren();
		}
		if ( !$this->incrementIncludeSize( 'arg', strlen( $text ) ) ) {
			$error = '';
			$this->limitationWarn( 'post-expand-template-argument' );
		}

		if ( $text === false && $object === false ) {
			# No match anywhere
			$object = $frame->virtualBracketedImplode( '{{{', '|', '}}}', $nameWithSpaces, $parts );
		}
		if ( $error !== false ) {
			$text .= $error;
		}
		if ( $object !== false ) {
			$ret = array( 'object' => $object );
		} else {
			$ret = array( 'text' => $text );
		}

		wfProfileOut( __METHOD__ );
		return $ret;
	}

	/**
	 * Return the text to be used for a given extension tag.
	 * This is the ghost of strip().
	 *
	 * @param $params Associative array of parameters:
	 *     name       PPNode for the tag name
	 *     attr       PPNode for unparsed text where tag attributes are thought to be
	 *     attributes Optional associative array of parsed attributes
	 *     inner      Contents of extension element
	 *     noClose    Original text did not have a close tag
	 * @param $frame PPFrame
	 *
	 * @return string
	 */
	function extensionSubstitution( $params, $frame ) {
		$name = $frame->expand( $params['name'] );
		$attrText = !isset( $params['attr'] ) ? null : $frame->expand( $params['attr'] );
		$content = !isset( $params['inner'] ) ? null : $frame->expand( $params['inner'] );
		$marker = "{$this->mUniqPrefix}-$name-" . sprintf( '%08X', $this->mMarkerIndex++ ) . self::MARKER_SUFFIX;

		$isFunctionTag = isset( $this->mFunctionTagHooks[strtolower($name)] ) &&
			( $this->ot['html'] || $this->ot['pre'] );
		if ( $isFunctionTag ) {
			$markerType = 'none';
		} else {
			$markerType = 'general';
		}
		if ( $this->ot['html'] || $isFunctionTag ) {
			$name = strtolower( $name );
			$attributes = Sanitizer::decodeTagAttributes( $attrText );
			if ( isset( $params['attributes'] ) ) {
				$attributes = $attributes + $params['attributes'];
			}

			if ( isset( $this->mTagHooks[$name] ) ) {
				# Workaround for PHP bug 35229 and similar
				if ( !is_callable( $this->mTagHooks[$name] ) ) {
					throw new MWException( "Tag hook for $name is not callable\n" );
				}
				$output = call_user_func_array( $this->mTagHooks[$name],
					array( $content, $attributes, $this, $frame ) );
			} elseif ( isset( $this->mFunctionTagHooks[$name] ) ) {
				list( $callback, $flags ) = $this->mFunctionTagHooks[$name];
				if ( !is_callable( $callback ) ) {
					throw new MWException( "Tag hook for $name is not callable\n" );
				}

				$output = call_user_func_array( $callback, array( &$this, $frame, $content, $attributes ) );
			} else {
				$output = 'Invalid tag extension name: ' .
					htmlspecialchars( $name ) . '';
			}

			if ( is_array( $output ) ) {
				# Extract flags to local scope (to override $markerType)
				$flags = $output;
				$output = $flags[0];
				unset( $flags[0] );
				extract( $flags );
			}
		} else {
			if ( is_null( $attrText ) ) {
				$attrText = '';
			}
			if ( isset( $params['attributes'] ) ) {
				foreach ( $params['attributes'] as $attrName => $attrValue ) {
					$attrText .= ' ' . htmlspecialchars( $attrName ) . '="' .
						htmlspecialchars( $attrValue ) . '"';
				}
			}
			if ( $content === null ) {
				$output = "<$name$attrText/>";
			} else {
				$close = is_null( $params['close'] ) ? '' : $frame->expand( $params['close'] );
				$output = "<$name$attrText>$content$close";
			}
		}

		if ( $markerType === 'none' ) {
			return $output;
		} elseif ( $markerType === 'nowiki' ) {
			$this->mStripState->addNoWiki( $marker, $output );
		} elseif ( $markerType === 'general' ) {
			$this->mStripState->addGeneral( $marker, $output );
		} else {
			throw new MWException( __METHOD__.': invalid marker type' );
		}
		return $marker;
	}

	/**
	 * Increment an include size counter
	 *
	 * @param $type String: the type of expansion
	 * @param $size Integer: the size of the text
	 * @return Boolean: false if this inclusion would take it over the maximum, true otherwise
	 */
	function incrementIncludeSize( $type, $size ) {
		if ( $this->mIncludeSizes[$type] + $size > $this->mOptions->getMaxIncludeSize() ) {
			return false;
		} else {
			$this->mIncludeSizes[$type] += $size;
			return true;
		}
	}

	/**
	 * Increment the expensive function count
	 *
	 * @return Boolean: false if the limit has been exceeded
	 */
	function incrementExpensiveFunctionCount() {
		global $wgExpensiveParserFunctionLimit;
		$this->mExpensiveFunctionCount++;
		if ( $this->mExpensiveFunctionCount <= $wgExpensiveParserFunctionLimit ) {
			return true;
		}
		return false;
	}

	/**
	 * Strip double-underscore items like __NOGALLERY__ and __NOTOC__
	 * Fills $this->mDoubleUnderscores, returns the modified text
	 */
	function doDoubleUnderscore( $text ) {
		wfProfileIn( __METHOD__ );

		# The position of __TOC__ needs to be recorded
		$mw = MagicWord::get( 'toc' );
		if ( $mw->match( $text ) ) {
			$this->mShowToc = true;
			$this->mForceTocPosition = true;

			# Set a placeholder. At the end we'll fill it in with the TOC.
			$text = $mw->replace( '', $text, 1 );

			# Only keep the first one.
			$text = $mw->replace( '', $text );
		}

		# Now match and remove the rest of them
		$mwa = MagicWord::getDoubleUnderscoreArray();
		$this->mDoubleUnderscores = $mwa->matchAndRemove( $text );

		if ( isset( $this->mDoubleUnderscores['nogallery'] ) ) {
			$this->mOutput->mNoGallery = true;
		}
		if ( isset( $this->mDoubleUnderscores['notoc'] ) && !$this->mForceTocPosition ) {
			$this->mShowToc = false;
		}
		if ( isset( $this->mDoubleUnderscores['hiddencat'] ) && $this->mTitle->getNamespace() == NS_CATEGORY ) {
			$this->addTrackingCategory( 'hidden-category-category' );
		}
		# (bug 8068) Allow control over whether robots index a page.
		#
		# @todo FIXME: Bug 14899: __INDEX__ always overrides __NOINDEX__ here!  This
		# is not desirable, the last one on the page should win.
		if ( isset( $this->mDoubleUnderscores['noindex'] ) && $this->mTitle->canUseNoindex() ) {
			$this->mOutput->setIndexPolicy( 'noindex' );
			$this->addTrackingCategory( 'noindex-category' );
		}
		if ( isset( $this->mDoubleUnderscores['index'] ) && $this->mTitle->canUseNoindex() ) {
			$this->mOutput->setIndexPolicy( 'index' );
			$this->addTrackingCategory( 'index-category' );
		}

		# Cache all double underscores in the database
		foreach ( $this->mDoubleUnderscores as $key => $val ) {
			$this->mOutput->setProperty( $key, '' );
		}

		wfProfileOut( __METHOD__ );
		return $text;
	}

	/**
	 * Add a tracking category, getting the title from a system message,
	 * or print a debug message if the title is invalid.
	 *
	 * @param $msg String: message key
	 * @return Boolean: whether the addition was successful
	 */
	protected function addTrackingCategory( $msg ) {
		if ( $this->mTitle->getNamespace() === NS_SPECIAL ) {
			wfDebug( __METHOD__.": Not adding tracking category $msg to special page!\n" );
			return false;
		}
		$cat = wfMsgForContent( $msg );

		# Allow tracking categories to be disabled by setting them to "-"
		if ( $cat === '-' ) {
			return false;
		}

		$containerCategory = Title::makeTitleSafe( NS_CATEGORY, $cat );
		if ( $containerCategory ) {
			$this->mOutput->addCategory( $containerCategory->getDBkey(), $this->getDefaultSort() );
			return true;
		} else {
			wfDebug( __METHOD__.": [[MediaWiki:$msg]] is not a valid title!\n" );
			return false;
		}
	}

	/**
	 * This function accomplishes several tasks:
	 * 1) Auto-number headings if that option is enabled
	 * 2) Add an [edit] link to sections for users who have enabled the option and can edit the page
	 * 3) Add a Table of contents on the top for users who have enabled the option
	 * 4) Auto-anchor headings
	 *
	 * It loops through all headlines, collects the necessary data, then splits up the
	 * string and re-inserts the newly formatted headlines.
	 *
	 * @param $text String
	 * @param $origText String: original, untouched wikitext
	 * @param $isMain Boolean
	 * @private
	 */
	function formatHeadings( $text, $origText, $isMain=true ) {
		global $wgMaxTocLevel, $wgHtml5, $wgExperimentalHtmlIds;

		# Inhibit editsection links if requested in the page
		if ( isset( $this->mDoubleUnderscores['noeditsection'] ) ) {
			$showEditLink = 0;
		} else {
			$showEditLink = $this->mOptions->getEditSection();
		}
		if ( $showEditLink ) {
			$this->mOutput->setEditSectionTokens( true );
		}

		# Get all headlines for numbering them and adding funky stuff like [edit]
		# links - this is for later, but we need the number of headlines right now
		$matches = array();
		$numMatches = preg_match_all( '/[1-6])(?P.*?'.'>)(?P
.*?)<\/H[1-6] *>/i', $text, $matches );

		# if there are fewer than 4 headlines in the article, do not show TOC
		# unless it's been explicitly enabled.
		$enoughToc = $this->mShowToc &&
			( ( $numMatches >= 4 ) || $this->mForceTocPosition );

		# Allow user to stipulate that a page should have a "new section"
		# link added via __NEWSECTIONLINK__
		if ( isset( $this->mDoubleUnderscores['newsectionlink'] ) ) {
			$this->mOutput->setNewSection( true );
		}

		# Allow user to remove the "new section"
		# link via __NONEWSECTIONLINK__
		if ( isset( $this->mDoubleUnderscores['nonewsectionlink'] ) ) {
			$this->mOutput->hideNewSection( true );
		}

		# if the string __FORCETOC__ (not case-sensitive) occurs in the HTML,
		# override above conditions and always show TOC above first header
		if ( isset( $this->mDoubleUnderscores['forcetoc'] ) ) {
			$this->mShowToc = true;
			$enoughToc = true;
		}

		# headline counter
		$headlineCount = 0;
		$numVisible = 0;

		# Ugh .. the TOC should have neat indentation levels which can be
		# passed to the skin functions. These are determined here
		$toc = '';
		$full = '';
		$head = array();
		$sublevelCount = array();
		$levelCount = array();
		$level = 0;
		$prevlevel = 0;
		$toclevel = 0;
		$prevtoclevel = 0;
		$markerRegex = "{$this->mUniqPrefix}-h-(\d+)-" . self::MARKER_SUFFIX;
		$baseTitleText = $this->mTitle->getPrefixedDBkey();
		$oldType = $this->mOutputType;
		$this->setOutputType( self::OT_WIKI );
		$frame = $this->getPreprocessor()->newFrame();
		$root = $this->preprocessToDom( $origText );
		$node = $root->getFirstChild();
		$byteOffset = 0;
		$tocraw = array();
		$refers = array();

		foreach ( $matches[3] as $headline ) {
			$isTemplate = false;
			$titleText = false;
			$sectionIndex = false;
			$numbering = '';
			$markerMatches = array();
			if ( preg_match("/^$markerRegex/", $headline, $markerMatches ) ) {
				$serial = $markerMatches[1];
				list( $titleText, $sectionIndex ) = $this->mHeadings[$serial];
				$isTemplate = ( $titleText != $baseTitleText );
				$headline = preg_replace( "/^$markerRegex/", "", $headline );
			}

			if ( $toclevel ) {
				$prevlevel = $level;
			}
			$level = $matches[1][$headlineCount];

			if ( $level > $prevlevel ) {
				# Increase TOC level
				$toclevel++;
				$sublevelCount[$toclevel] = 0;
				if ( $toclevel<$wgMaxTocLevel ) {
					$prevtoclevel = $toclevel;
					$toc .= Linker::tocIndent();
					$numVisible++;
				}
			} elseif ( $level < $prevlevel && $toclevel > 1 ) {
				# Decrease TOC level, find level to jump to

				for ( $i = $toclevel; $i > 0; $i-- ) {
					if ( $levelCount[$i] == $level ) {
						# Found last matching level
						$toclevel = $i;
						break;
					} elseif ( $levelCount[$i] < $level ) {
						# Found first matching level below current level
						$toclevel = $i + 1;
						break;
					}
				}
				if ( $i == 0 ) {
					$toclevel = 1;
				}
				if ( $toclevel<$wgMaxTocLevel ) {
					if ( $prevtoclevel < $wgMaxTocLevel ) {
						# Unindent only if the previous toc level was shown :p
						$toc .= Linker::tocUnindent( $prevtoclevel - $toclevel );
						$prevtoclevel = $toclevel;
					} else {
						$toc .= Linker::tocLineEnd();
					}
				}
			} else {
				# No change in level, end TOC line
				if ( $toclevel<$wgMaxTocLevel ) {
					$toc .= Linker::tocLineEnd();
				}
			}

			$levelCount[$toclevel] = $level;

			# count number of headlines for each level
			@$sublevelCount[$toclevel]++;
			$dot = 0;
			for( $i = 1; $i <= $toclevel; $i++ ) {
				if ( !empty( $sublevelCount[$i] ) ) {
					if ( $dot ) {
						$numbering .= '.';
					}
					$numbering .= $this->getFunctionLang()->formatNum( $sublevelCount[$i] );
					$dot = 1;
				}
			}

			# The safe header is a version of the header text safe to use for links
			# Avoid insertion of weird stuff like $by\; expanding\; the\; relevant\; sections\; \$safeHeadline\; =\; \$this->mStripState->unstripBoth(\; \$headline\; );\; \#\; Remove\; link\; placeholders\; by\; the\; link\; text.\; \#\#\; turns\; into\; \#\; link\; text\; with\; suffix\; \$safeHeadline\; =\; \$this->replaceLinkHoldersText(\; \$safeHeadline\; );\; \#\; Strip\; out\; HTML\; (other\; than\; plainand$: bug 8393)
			$tocline = preg_replace(
				array( '#<(?!/?(sup|sub)).*?'.'>#', '#<(/?(sup|sub)).*?'.'>#' ),
				array( '',                          '<$1>' ),
				$safeHeadline
			);
			$tocline = trim( $tocline );

			# For the anchor, strip out HTML-y stuff period
			$safeHeadline = preg_replace( '/<.*?'.'>/', '', $safeHeadline );
			$safeHeadline = Sanitizer::normalizeSectionNameWhitespace( $safeHeadline );

			# Save headline for section edit hint before it's escaped
			$headlineHint = $safeHeadline;

			if ( $wgHtml5 && $wgExperimentalHtmlIds ) {
				# For reverse compatibility, provide an id that's
				# HTML4-compatible, like we used to.
				#
				# It may be worth noting, academically, that it's possible for
				# the legacy anchor to conflict with a non-legacy headline
				# anchor on the page.  In this case likely the "correct" thing
				# would be to either drop the legacy anchors or make sure
				# they're numbered first.  However, this would require people
				# to type in section names like "abc_.D7.93.D7.90.D7.A4"
				# manually, so let's not bother worrying about it.
				$legacyHeadline = Sanitizer::escapeId( $safeHeadline,
					array( 'noninitial', 'legacy' ) );
				$safeHeadline = Sanitizer::escapeId( $safeHeadline );

				if ( $legacyHeadline == $safeHeadline ) {
					# No reason to have both (in fact, we can't)
					$legacyHeadline = false;
				}
			} else {
				$legacyHeadline = false;
				$safeHeadline = Sanitizer::escapeId( $safeHeadline,
					'noninitial' );
			}

			# HTML names must be case-insensitively unique (bug 10721).
			# This does not apply to Unicode characters per
			# http://dev.w3.org/html5/spec/infrastructure.html#case-sensitivity-and-string-comparison
			# @todo FIXME: We may be changing them depending on the current locale.
			$arrayKey = strtolower( $safeHeadline );
			if ( $legacyHeadline === false ) {
				$legacyArrayKey = false;
			} else {
				$legacyArrayKey = strtolower( $legacyHeadline );
			}

			# count how many in assoc. array so we can track dupes in anchors
			if ( isset( $refers[$arrayKey] ) ) {
				$refers[$arrayKey]++;
			} else {
				$refers[$arrayKey] = 1;
			}
			if ( isset( $refers[$legacyArrayKey] ) ) {
				$refers[$legacyArrayKey]++;
			} else {
				$refers[$legacyArrayKey] = 1;
			}

			# Don't number the heading if it is the only one (looks silly)
			if ( count( $matches[3] ) > 1 && $this->mOptions->getNumberHeadings() ) {
				# the two are different if the line contains a link
				$headline = $numbering . ' ' . $headline;
			}

			# Create the anchor for linking from the TOC to the section
			$anchor = $safeHeadline;
			$legacyAnchor = $legacyHeadline;
			if ( $refers[$arrayKey] > 1 ) {
				$anchor .= '_' . $refers[$arrayKey];
			}
			if ( $legacyHeadline !== false && $refers[$legacyArrayKey] > 1 ) {
				$legacyAnchor .= '_' . $refers[$legacyArrayKey];
			}
			if ( $enoughToc && ( !isset( $wgMaxTocLevel ) || $toclevel < $wgMaxTocLevel ) ) {
				$toc .= Linker::tocLine( $anchor, $tocline,
					$numbering, $toclevel, ( $isTemplate ? false : $sectionIndex ) );
			}

			# Add the section to the section tree
			# Find the DOM node for this header
			while ( $node && !$isTemplate ) {
				if ( $node->getName() === 'h' ) {
					$bits = $node->splitHeading();
					if ( $bits['i'] == $sectionIndex ) {
						break;
					}
				}
				$byteOffset += mb_strlen( $this->mStripState->unstripBoth(
					$frame->expand( $node, PPFrame::RECOVER_ORIG ) ) );
				$node = $node->getNextSibling();
			}
			$tocraw[] = array(
				'toclevel' => $toclevel,
				'level' => $level,
				'line' => $tocline,
				'number' => $numbering,
				'index' => ( $isTemplate ? 'T-' : '' ) . $sectionIndex,
				'fromtitle' => $titleText,
				'byteoffset' => ( $isTemplate ? null : $byteOffset ),
				'anchor' => $anchor,
			);

			# give headline the correct  tag
			if ( $sectionIndex !== false ) {
				// Output edit section links as markers with styles that can be customized by skins
				if ( $isTemplate ) {
					# Put a T flag in the section identifier, to indicate to extractSections()
					# that sections inside  should be counted.
					$editlinkArgs = array( $titleText, "T-$sectionIndex"/*, null */ );
				} else {
					$editlinkArgs = array( $this->mTitle->getPrefixedText(), $sectionIndex, $headlineHint );
				}
				// We use a bit of pesudo-xml for editsection markers. The language converter is run later on
				// Using a UNIQ style marker leads to the converter screwing up the tokens when it converts stuff
				// And trying to insert strip tags fails too. At this point all real inputted tags have already been escaped
				// so we don't have to worry about a user trying to input one of these markers directly.
				// We use a page and section attribute to stop the language converter from converting these important bits
				// of data, but put the headline hint inside a content block because the language converter is supposed to
				// be able to convert that piece of data.
				$editlink = '';
				} else {
					$editlink .= '/>';
				}
			} else {
				$editlink = '';
			}
			$head[$headlineCount] = Linker::makeHeadline( $level,
				$matches['attrib'][$headlineCount], $anchor, $headline,
				$editlink, $legacyAnchor );

			$headlineCount++;
		}

		$this->setOutputType( $oldType );

		# Never ever show TOC if no headers
		if ( $numVisible < 1 ) {
			$enoughToc = false;
		}

		if ( $enoughToc ) {
			if ( $prevtoclevel > 0 && $prevtoclevel < $wgMaxTocLevel ) {
				$toc .= Linker::tocUnindent( $prevtoclevel - 1 );
			}
			$toc = Linker::tocList( $toc, $this->mOptions->getUserLang() );
			$this->mOutput->setTOCHTML( $toc );
		}

		if ( $isMain ) {
			$this->mOutput->setSections( $tocraw );
		}

		# split up and insert constructed headlines

		$blocks = preg_split( '/.*?<\/H[1-6]>/i', $text );
		$i = 0;

		foreach ( $blocks as $block ) {
			if ( $showEditLink && $headlineCount > 0 && $i == 0 && $block !== "\n" ) {
				# This is the [edit] link that appears for the top block of text when
				# section editing is enabled

				# Disabled because it broke block formatting
				# For example, a bullet point in the top line
				# $full .= $sk->editSectionLink(0);
			}
			$full .= $block;
			if ( $enoughToc && !$i && $isMain && !$this->mForceTocPosition ) {
				# Top anchor now in skin
				$full = $full.$toc;
			}

			if ( !empty( $head[$i] ) ) {
				$full .= $head[$i];
			}
			$i++;
		}
		if ( $this->mForceTocPosition ) {
			return str_replace( '', $toc, $full );
		} else {
			return $full;
		}
	}

	/**
	 * Transform wiki markup when saving a page by doing \r\n -> \n
	 * conversion, substitting signatures, {{subst:}} templates, etc.
	 *
	 * @param $text String: the text to transform
	 * @param $title Title: the Title object for the current article
	 * @param $user User: the User object describing the current user
	 * @param $options ParserOptions: parsing options
	 * @param $clearState Boolean: whether to clear the parser state first
	 * @return String: the altered wiki markup
	 */
	public function preSaveTransform( $text, Title $title, User $user, ParserOptions $options, $clearState = true ) {
		$this->startParse( $title, $options, self::OT_WIKI, $clearState );
		$this->setUser( $user );

		$pairs = array(
			"\r\n" => "\n",
		);
		$text = str_replace( array_keys( $pairs ), array_values( $pairs ), $text );
		if( $options->getPreSaveTransform() ) {
			$text = $this->pstPass2( $text, $user );
		}
		$text = $this->mStripState->unstripBoth( $text );

		$this->setUser( null ); #Reset

		return $text;
	}

	/**
	 * Pre-save transform helper function
	 * @private
	 */
	function pstPass2( $text, $user ) {
		global $wgContLang, $wgLocaltimezone;

		# Note: This is the timestamp saved as hardcoded wikitext to
		# the database, we use $wgContLang here in order to give
		# everyone the same signature and use the default one rather
		# than the one selected in each user's preferences.
		# (see also bug 12815)
		$ts = $this->mOptions->getTimestamp();
		if ( isset( $wgLocaltimezone ) ) {
			$tz = $wgLocaltimezone;
		} else {
			$tz = date_default_timezone_get();
		}

		$unixts = wfTimestamp( TS_UNIX, $ts );
		$oldtz = date_default_timezone_get();
		date_default_timezone_set( $tz );
		$ts = date( 'YmdHis', $unixts );
		$tzMsg = date( 'T', $unixts );  # might vary on DST changeover!

		# Allow translation of timezones through wiki. date() can return
		# whatever crap the system uses, localised or not, so we cannot
		# ship premade translations.
		$key = 'timezone-' . strtolower( trim( $tzMsg ) );
		$msg = wfMessage( $key )->inContentLanguage();
		if ( $msg->exists() ) {
			$tzMsg = $msg->text();
		}

		date_default_timezone_set( $oldtz );

		$d = $wgContLang->timeanddate( $ts, false, false ) . " ($tzMsg)";

		# Variable replacement
		# Because mOutputType is OT_WIKI, this will only process {{subst:xxx}} type tags
		$text = $this->replaceVariables( $text );

		# This works almost by chance, as the replaceVariables are done before the getUserSig(),
		# which may corrupt this parser instance via its wfMsgExt( parsemag ) call-

		# Signatures
		$sigText = $this->getUserSig( $user );
		$text = strtr( $text, array(
			'~~~~~' => $d,
			'~~~~' => "$sigText $d",
			'~~~' => $sigText
		) );

		# Context links: [[|name]] and [[name (context)|]]
		global $wgLegalTitleChars;
		$tc = "[$wgLegalTitleChars]";
		$nc = '[ _0-9A-Za-z\x80-\xff-]'; # Namespaces can use non-ascii!

		$p1 = "/\[\[(:?$nc+:|:|)($tc+?)( \\($tc+\\))\\|]]/";		# [[ns:page (context)|]]
		$p4 = "/\[\[(:?$nc+:|:|)($tc+?)(（$tc+）)\\|]]/";		# [[ns:page（context）|]]
		$p3 = "/\[\[(:?$nc+:|:|)($tc+?)( \\($tc+\\)|)(, $tc+|)\\|]]/";	# [[ns:page (context), context|]]
		$p2 = "/\[\[\\|($tc+)]]/";					# [[|page]]

		# try $p1 first, to turn "[[A, B (C)|]]" into "[[A, B (C)|A, B]]"
		$text = preg_replace( $p1, '[[\\1\\2\\3|\\2]]', $text );
		$text = preg_replace( $p4, '[[\\1\\2\\3|\\2]]', $text );
		$text = preg_replace( $p3, '[[\\1\\2\\3\\4|\\2]]', $text );

		$t = $this->mTitle->getText();
		$m = array();
		if ( preg_match( "/^($nc+:|)$tc+?( \\($tc+\\))$/", $t, $m ) ) {
			$text = preg_replace( $p2, "[[$m[1]\\1$m[2]|\\1]]", $text );
		} elseif ( preg_match( "/^($nc+:|)$tc+?(, $tc+|)$/", $t, $m ) && "$m[1]$m[2]" != '' ) {
			$text = preg_replace( $p2, "[[$m[1]\\1$m[2]|\\1]]", $text );
		} else {
			# if there's no context, don't bother duplicating the title
			$text = preg_replace( $p2, '[[\\1]]', $text );
		}

		# Trim trailing whitespace
		$text = rtrim( $text );

		return $text;
	}

	/**
	 * Fetch the user's signature text, if any, and normalize to
	 * validated, ready-to-insert wikitext.
	 * If you have pre-fetched the nickname or the fancySig option, you can
	 * specify them here to save a database query.
	 * Do not reuse this parser instance after calling getUserSig(),
	 * as it may have changed if it's the $wgParser.
	 *
	 * @param $user User
	 * @param $nickname String: nickname to use or false to use user's default nickname
	 * @param $fancySig Boolean: whether the nicknname is the complete signature
	 *                  or null to use default value
	 * @return string
	 */
	function getUserSig( &$user, $nickname = false, $fancySig = null ) {
		global $wgMaxSigChars;

		$username = $user->getName();

		# If not given, retrieve from the user object.
		if ( $nickname === false )
			$nickname = $user->getOption( 'nickname' );

		if ( is_null( $fancySig ) ) {
			$fancySig = $user->getBoolOption( 'fancysig' );
		}

		$nickname = $nickname == null ? $username : $nickname;

		if ( mb_strlen( $nickname ) > $wgMaxSigChars ) {
			$nickname = $username;
			wfDebug( __METHOD__ . ": $username has overlong signature.\n" );
		} elseif ( $fancySig !== false ) {
			# Sig. might contain markup; validate this
			if ( $this->validateSig( $nickname ) !== false ) {
				# Validated; clean up (if needed) and return it
				return $this->cleanSig( $nickname, true );
			} else {
				# Failed to validate; fall back to the default
				$nickname = $username;
				wfDebug( __METHOD__.": $username has bad XML tags in signature.\n" );
			}
		}

		# Make sure nickname doesnt get a sig in a sig
		$nickname = $this->cleanSigInSig( $nickname );

		# If we're still here, make it a link to the user page
		$userText = wfEscapeWikiText( $username );
		$nickText = wfEscapeWikiText( $nickname );
		$msgName = $user->isAnon() ? 'signature-anon' : 'signature';

		return wfMessage( $msgName, $userText, $nickText )->inContentLanguage()->title( $this->getTitle() )->text();
	}

	/**
	 * Check that the user's signature contains no bad XML
	 *
	 * @param $text String
	 * @return mixed An expanded string, or false if invalid.
	 */
	function validateSig( $text ) {
		return( Xml::isWellFormedXmlFragment( $text ) ? $text : false );
	}

	/**
	 * Clean up signature text
	 *
	 * 1) Strip ~~~, ~~~~ and ~~~~~ out of signatures @see cleanSigInSig
	 * 2) Substitute all transclusions
	 *
	 * @param $text String
	 * @param $parsing Whether we're cleaning (preferences save) or parsing
	 * @return String: signature text
	 */
	function cleanSig( $text, $parsing = false ) {
		if ( !$parsing ) {
			global $wgTitle;
			$this->mOptions = new ParserOptions;
			$this->clearState();
			$this->setTitle( $wgTitle );
			$this->setOutputType = self::OT_PREPROCESS;
		}

		# Option to disable this feature
		if ( !$this->mOptions->getCleanSignatures() ) {
			return $text;
		}

		# @todo FIXME: Regex doesn't respect extension tags or nowiki
		#  => Move this logic to braceSubstitution()
		$substWord = MagicWord::get( 'subst' );
		$substRegex = '/\{\{(?!(?:' . $substWord->getBaseRegex() . '))/x' . $substWord->getRegexCase();
		$substText = '{{' . $substWord->getSynonym( 0 );

		$text = preg_replace( $substRegex, $substText, $text );
		$text = $this->cleanSigInSig( $text );
		$dom = $this->preprocessToDom( $text );
		$frame = $this->getPreprocessor()->newFrame();
		$text = $frame->expand( $dom );

		if ( !$parsing ) {
			$text = $this->mStripState->unstripBoth( $text );
		}

		return $text;
	}

	/**
	 * Strip ~~~, ~~~~ and ~~~~~ out of signatures
	 *
	 * @param $text String
	 * @return String: signature text with /~{3,5}/ removed
	 */
	function cleanSigInSig( $text ) {
		$text = preg_replace( '/~{3,5}/', '', $text );
		return $text;
	}

	/**
	 * Set up some variables which are usually set up in parse()
	 * so that an external function can call some class members with confidence
	 */
	public function startExternalParse( Title $title = null, ParserOptions $options, $outputType, $clearState = true ) {
		$this->startParse( $title, $options, $outputType, $clearState );
	}

	private function startParse( Title $title = null, ParserOptions $options, $outputType, $clearState = true ) {
		$this->setTitle( $title );
		$this->mOptions = $options;
		$this->setOutputType( $outputType );
		if ( $clearState ) {
			$this->clearState();
		}
	}

	/**
	 * Wrapper for preprocess()
	 *
	 * @param $text String: the text to preprocess
	 * @param $options ParserOptions: options
	 * @param $title Title object or null to use $wgTitle
	 * @return String
	 */
	public function transformMsg( $text, $options, $title = null ) {
		static $executing = false;

		# Guard against infinite recursion
		if ( $executing ) {
			return $text;
		}
		$executing = true;

		wfProfileIn( __METHOD__ );
		if ( !$title ) {
			global $wgTitle;
			$title = $wgTitle;
		}
		if ( !$title ) {
			# It's not uncommon having a null $wgTitle in scripts. See r80898
			# Create a ghost title in such case
			$title = Title::newFromText( 'Dwimmerlaik' );
		}
		$text = $this->preprocess( $text, $title, $options );

		$executing = false;
		wfProfileOut( __METHOD__ );
		return $text;
	}

	/**
	 * Create an HTML-style tag, e.g. special text
	 * The callback should have the following form:
	 *    function myParserHook( $text, $params, $parser, $frame ) { ... }
	 *
	 * Transform and return $text. Use $parser for any required context, e.g. use
	 * $parser->getTitle() and $parser->getOptions() not $wgTitle or $wgOut->mParserOptions
	 *
	 * Hooks may return extended information by returning an array, of which the
	 * first numbered element (index 0) must be the return string, and all other
	 * entries are extracted into local variables within an internal function
	 * in the Parser class.
	 *
	 * This interface (introduced r61913) appears to be undocumented, but
	 * 'markerName' is used by some core tag hooks to override which strip
	 * array their results are placed in. **Use great caution if attempting
	 * this interface, as it is not documented and injudicious use could smash
	 * private variables.**
	 *
	 * @param $tag Mixed: the tag to use, e.g. 'hook' for 
	 * @param $callback Mixed: the callback function (and object) to use for the tag
	 * @return The old value of the mTagHooks array associated with the hook
	 */
	public function setHook( $tag, $callback ) {
		$tag = strtolower( $tag );
		if ( preg_match( '/[<>\r\n]/', $tag, $m ) ) throw new MWException( "Invalid character {$m[0]} in setHook('$tag', ...) call" );
		$oldVal = isset( $this->mTagHooks[$tag] ) ? $this->mTagHooks[$tag] : null;
		$this->mTagHooks[$tag] = $callback;
		if ( !in_array( $tag, $this->mStripList ) ) {
			$this->mStripList[] = $tag;
		}

		return $oldVal;
	}

	/**
	 * As setHook(), but letting the contents be parsed.
	 *
	 * Transparent tag hooks are like regular XML-style tag hooks, except they
	 * operate late in the transformation sequence, on HTML instead of wikitext.
	 *
	 * This is probably obsoleted by things dealing with parser frames?
	 * The only extension currently using it is geoserver.
	 *
	 * @since 1.10
	 * @todo better document or deprecate this
	 *
	 * @param $tag Mixed: the tag to use, e.g. 'hook' for 
	 * @param $callback Mixed: the callback function (and object) to use for the tag
	 * @return The old value of the mTagHooks array associated with the hook
	 */
	function setTransparentTagHook( $tag, $callback ) {
		$tag = strtolower( $tag );
		if ( preg_match( '/[<>\r\n]/', $tag, $m ) ) throw new MWException( "Invalid character {$m[0]} in setTransparentHook('$tag', ...) call" );
		$oldVal = isset( $this->mTransparentTagHooks[$tag] ) ? $this->mTransparentTagHooks[$tag] : null;
		$this->mTransparentTagHooks[$tag] = $callback;

		return $oldVal;
	}

	/**
	 * Remove all tag hooks
	 */
	function clearTagHooks() {
		$this->mTagHooks = array();
		$this->mStripList = $this->mDefaultStripList;
	}

	/**
	 * Create a function, e.g. {{sum:1|2|3}}
	 * The callback function should have the form:
	 *    function myParserFunction( &$parser, $arg1, $arg2, $arg3 ) { ... }
	 *
	 * Or with SFH_OBJECT_ARGS:
	 *    function myParserFunction( $parser, $frame, $args ) { ... }
	 *
	 * The callback may either return the text result of the function, or an array with the text
	 * in element 0, and a number of flags in the other elements. The names of the flags are
	 * specified in the keys. Valid flags are:
	 *   found                     The text returned is valid, stop processing the template. This
	 *                             is on by default.
	 *   nowiki                    Wiki markup in the return value should be escaped
	 *   isHTML                    The returned text is HTML, armour it against wikitext transformation
	 *
	 * @param $id String: The magic word ID
	 * @param $callback Mixed: the callback function (and object) to use
	 * @param $flags Integer: a combination of the following flags:
	 *     SFH_NO_HASH   No leading hash, i.e. {{plural:...}} instead of {{#if:...}}
	 *
	 *     SFH_OBJECT_ARGS   Pass the template arguments as PPNode objects instead of text. This
	 *     allows for conditional expansion of the parse tree, allowing you to eliminate dead
	 *     branches and thus speed up parsing. It is also possible to analyse the parse tree of
	 *     the arguments, and to control the way they are expanded.
	 *
	 *     The $frame parameter is a PPFrame. This can be used to produce expanded text from the
	 *     arguments, for instance:
	 *         $text = isset( $args[0] ) ? $frame->expand( $args[0] ) : '';
	 *
	 *     For technical reasons, $args[0] is pre-expanded and will be a string. This may change in
	 *     future versions. Please call $frame->expand() on it anyway so that your code keeps
	 *     working if/when this is changed.
	 *
	 *     If you want whitespace to be trimmed from $args, you need to do it yourself, post-
	 *     expansion.
	 *
	 *     Please read the documentation in includes/parser/Preprocessor.php for more information
	 *     about the methods available in PPFrame and PPNode.
	 *
	 * @return The old callback function for this name, if any
	 */
	public function setFunctionHook( $id, $callback, $flags = 0 ) {
		global $wgContLang;

		$oldVal = isset( $this->mFunctionHooks[$id] ) ? $this->mFunctionHooks[$id][0] : null;
		$this->mFunctionHooks[$id] = array( $callback, $flags );

		# Add to function cache
		$mw = MagicWord::get( $id );
		if ( !$mw )
			throw new MWException( __METHOD__.'() expecting a magic word identifier.' );

		$synonyms = $mw->getSynonyms();
		$sensitive = intval( $mw->isCaseSensitive() );

		foreach ( $synonyms as $syn ) {
			# Case
			if ( !$sensitive ) {
				$syn = $wgContLang->lc( $syn );
			}
			# Add leading hash
			if ( !( $flags & SFH_NO_HASH ) ) {
				$syn = '#' . $syn;
			}
			# Remove trailing colon
			if ( substr( $syn, -1, 1 ) === ':' ) {
				$syn = substr( $syn, 0, -1 );
			}
			$this->mFunctionSynonyms[$sensitive][$syn] = $id;
		}
		return $oldVal;
	}

	/**
	 * Get all registered function hook identifiers
	 *
	 * @return Array
	 */
	function getFunctionHooks() {
		return array_keys( $this->mFunctionHooks );
	}

	/**
	 * Create a tag function, e.g. some stuff.
	 * Unlike tag hooks, tag functions are parsed at preprocessor level.
	 * Unlike parser functions, their content is not preprocessed.
	 */
	function setFunctionTagHook( $tag, $callback, $flags ) {
		$tag = strtolower( $tag );
		if ( preg_match( '/[<>\r\n]/', $tag, $m ) ) throw new MWException( "Invalid character {$m[0]} in setFunctionTagHook('$tag', ...) call" );
		$old = isset( $this->mFunctionTagHooks[$tag] ) ?
			$this->mFunctionTagHooks[$tag] : null;
		$this->mFunctionTagHooks[$tag] = array( $callback, $flags );

		if ( !in_array( $tag, $this->mStripList ) ) {
			$this->mStripList[] = $tag;
		}

		return $old;
	}

	/**
	 * @todo FIXME: Update documentation. makeLinkObj() is deprecated.
	 * Replace  link placeholders with actual links, in the buffer
	 * Placeholders created in Skin::makeLinkObj()
	 * Returns an array of link CSS classes, indexed by PDBK.
	 */
	function replaceLinkHolders( &$text, $options = 0 ) {
		return $this->mLinkHolders->replace( $text );
	}

	/**
	 * Replace  link placeholders with plain text of links
	 * (not HTML-formatted).
	 *
	 * @param $text String
	 * @return String
	 */
	function replaceLinkHoldersText( $text ) {
		return $this->mLinkHolders->replaceText( $text );
	}

	/**
	 * Renders an image gallery from a text with one line per image.
	 * text labels may be given by using |-style alternative text. E.g.
	 *   Image:one.jpg|The number "1"
	 *   Image:tree.jpg|A tree
	 * given as text will return the HTML of a gallery with two images,
	 * labeled 'The number "1"' and
	 * 'A tree'.
	 *
	 * @param string $text
	 * @param array $param
	 * @return string HTML
	 */
	function renderImageGallery( $text, $params ) {
		$ig = new ImageGallery();
		$ig->setContextTitle( $this->mTitle );
		$ig->setShowBytes( false );
		$ig->setShowFilename( false );
		$ig->setParser( $this );
		$ig->setHideBadImages();
		$ig->setAttributes( Sanitizer::validateTagAttributes( $params, 'table' ) );

		if ( isset( $params['showfilename'] ) ) {
			$ig->setShowFilename( true );
		} else {
			$ig->setShowFilename( false );
		}
		if ( isset( $params['caption'] ) ) {
			$caption = $params['caption'];
			$caption = htmlspecialchars( $caption );
			$caption = $this->replaceInternalLinks( $caption );
			$ig->setCaptionHtml( $caption );
		}
		if ( isset( $params['perrow'] ) ) {
			$ig->setPerRow( $params['perrow'] );
		}
		if ( isset( $params['widths'] ) ) {
			$ig->setWidths( $params['widths'] );
		}
		if ( isset( $params['heights'] ) ) {
			$ig->setHeights( $params['heights'] );
		}

		wfRunHooks( 'BeforeParserrenderImageGallery', array( &$this, &$ig ) );

		$lines = StringUtils::explode( "\n", $text );
		foreach ( $lines as $line ) {
			# match lines like these:
			# Image:someimage.jpg|This is some image
			$matches = array();
			preg_match( "/^([^|]+)(\\|(.*))?$/", $line, $matches );
			# Skip empty lines
			if ( count( $matches ) == 0 ) {
				continue;
			}

			if ( strpos( $matches[0], '%' ) !== false ) {
				$matches[1] = rawurldecode( $matches[1] );
			}
			$title = Title::newFromText( $matches[1], NS_FILE );
			if ( is_null( $title ) ) {
				# Bogus title. Ignore these so we don't bomb out later.
				continue;
			}

			$label = '';
			$alt = '';
			if ( isset( $matches[3] ) ) {
				// look for an |alt= definition while trying not to break existing
				// captions with multiple pipes (|) in it, until a more sensible grammar
				// is defined for images in galleries

				$matches[3] = $this->recursiveTagParse( trim( $matches[3] ) );
				$altmatches = StringUtils::explode('|', $matches[3]);
				$magicWordAlt = MagicWord::get( 'img_alt' );

				foreach ( $altmatches as $altmatch ) {
					$match = $magicWordAlt->matchVariableStartToEnd( $altmatch );
					if ( $match ) {
						$alt = $this->stripAltText( $match, false );
					}
					else {
						// concatenate all other pipes
						$label .= '|' . $altmatch;
					}
				}
				// remove the first pipe
				$label = substr( $label, 1 );
			}

			$ig->add( $title, $label, $alt );
		}
		return $ig->toHTML();
	}

	function getImageParams( $handler ) {
		if ( $handler ) {
			$handlerClass = get_class( $handler );
		} else {
			$handlerClass = '';
		}
		if ( !isset( $this->mImageParams[$handlerClass]  ) ) {
			# Initialise static lists
			static $internalParamNames = array(
				'horizAlign' => array( 'left', 'right', 'center', 'none' ),
				'vertAlign' => array( 'baseline', 'sub', 'super', 'top', 'text-top', 'middle',
					'bottom', 'text-bottom' ),
				'frame' => array( 'thumbnail', 'manualthumb', 'framed', 'frameless',
					'upright', 'border', 'link', 'alt' ),
			);
			static $internalParamMap;
			if ( !$internalParamMap ) {
				$internalParamMap = array();
				foreach ( $internalParamNames as $type => $names ) {
					foreach ( $names as $name ) {
						$magicName = str_replace( '-', '_', "img_$name" );
						$internalParamMap[$magicName] = array( $type, $name );
					}
				}
			}

			# Add handler params
			$paramMap = $internalParamMap;
			if ( $handler ) {
				$handlerParamMap = $handler->getParamMap();
				foreach ( $handlerParamMap as $magic => $paramName ) {
					$paramMap[$magic] = array( 'handler', $paramName );
				}
			}
			$this->mImageParams[$handlerClass] = $paramMap;
			$this->mImageParamsMagicArray[$handlerClass] = new MagicWordArray( array_keys( $paramMap ) );
		}
		return array( $this->mImageParams[$handlerClass], $this->mImageParamsMagicArray[$handlerClass] );
	}

	/**
	 * Parse image options text and use it to make an image
	 *
	 * @param $title Title
	 * @param $options String
	 * @param $holders LinkHolderArray
	 * @return string HTML
	 */
	function makeImage( $title, $options, $holders = false ) {
		# Check if the options text is of the form "options|alt text"
		# Options are:
		#  * thumbnail  make a thumbnail with enlarge-icon and caption, alignment depends on lang
		#  * left       no resizing, just left align. label is used for alt= only
		#  * right      same, but right aligned
		#  * none       same, but not aligned
		#  * ___px      scale to ___ pixels width, no aligning. e.g. use in taxobox
		#  * center     center the image
		#  * frame      Keep original image size, no magnify-button.
		#  * framed     Same as "frame"
		#  * frameless  like 'thumb' but without a frame. Keeps user preferences for width
		#  * upright    reduce width for upright images, rounded to full __0 px
		#  * border     draw a 1px border around the image
		#  * alt        Text for HTML alt attribute (defaults to empty)
		#  * link       Set the target of the image link. Can be external, interwiki, or local
		# vertical-align values (no % or length right now):
		#  * baseline
		#  * sub
		#  * super
		#  * top
		#  * text-top
		#  * middle
		#  * bottom
		#  * text-bottom

		$parts = StringUtils::explode( "|", $options );

		# Give extensions a chance to select the file revision for us
		$time = $sha1 = $descQuery = false;
		wfRunHooks( 'BeforeParserFetchFileAndTitle',
			array( $this, $title, &$time, &$sha1, &$descQuery ) );
		# Fetch and register the file (file title may be different via hooks)
		list( $file, $title ) = $this->fetchFileAndTitle( $title, $time, $sha1 );

		# Get parameter map
		$handler = $file ? $file->getHandler() : false;

		list( $paramMap, $mwArray ) = $this->getImageParams( $handler );

		if ( !$file ) {
			$this->addTrackingCategory( 'broken-file-category' );
		}

		# Process the input parameters
		$caption = '';
		$params = array( 'frame' => array(), 'handler' => array(),
			'horizAlign' => array(), 'vertAlign' => array() );
		foreach ( $parts as $part ) {
			$part = trim( $part );
			list( $magicName, $value ) = $mwArray->matchVariableStartToEnd( $part );
			$validated = false;
			if ( isset( $paramMap[$magicName] ) ) {
				list( $type, $paramName ) = $paramMap[$magicName];

				# Special case; width and height come in one variable together
				if ( $type === 'handler' && $paramName === 'width' ) {
					$m = array();
					# (bug 13500) In both cases (width/height and width only),
					# permit trailing "px" for backward compatibility.
					if ( preg_match( '/^([0-9]*)x([0-9]*)\s*(?:px)?\s*$/', $value, $m ) ) {
						$width = intval( $m[1] );
						$height = intval( $m[2] );
						if ( $handler->validateParam( 'width', $width ) ) {
							$params[$type]['width'] = $width;
							$validated = true;
						}
						if ( $handler->validateParam( 'height', $height ) ) {
							$params[$type]['height'] = $height;
							$validated = true;
						}
					} elseif ( preg_match( '/^[0-9]*\s*(?:px)?\s*$/', $value ) ) {
						$width = intval( $value );
						if ( $handler->validateParam( 'width', $width ) ) {
							$params[$type]['width'] = $width;
							$validated = true;
						}
					} # else no validation -- bug 13436
				} else {
					if ( $type === 'handler' ) {
						# Validate handler parameter
						$validated = $handler->validateParam( $paramName, $value );
					} else {
						# Validate internal parameters
						switch( $paramName ) {
						case 'manualthumb':
						case 'alt':
							# @todo FIXME: Possibly check validity here for
							# manualthumb? downstream behavior seems odd with
							# missing manual thumbs.
							$validated = true;
							$value = $this->stripAltText( $value, $holders );
							break;
						case 'link':
							$chars = self::EXT_LINK_URL_CLASS;
							$prots = $this->mUrlProtocols;
							if ( $value === '' ) {
								$paramName = 'no-link';
								$value = true;
								$validated = true;
							} elseif ( preg_match( "/^$prots/", $value ) ) {
								if ( preg_match( "/^($prots)$chars+$/", $value, $m ) ) {
									$paramName = 'link-url';
									$this->mOutput->addExternalLink( $value );
									if ( $this->mOptions->getExternalLinkTarget() ) {
										$params[$type]['link-target'] = $this->mOptions->getExternalLinkTarget();
									}
									$validated = true;
								}
							} else {
								$linkTitle = Title::newFromText( $value );
								if ( $linkTitle ) {
									$paramName = 'link-title';
									$value = $linkTitle;
									$this->mOutput->addLink( $linkTitle );
									$validated = true;
								}
							}
							break;
						default:
							# Most other things appear to be empty or numeric...
							$validated = ( $value === false || is_numeric( trim( $value ) ) );
						}
					}

					if ( $validated ) {
						$params[$type][$paramName] = $value;
					}
				}
			}
			if ( !$validated ) {
				$caption = $part;
			}
		}

		# Process alignment parameters
		if ( $params['horizAlign'] ) {
			$params['frame']['align'] = key( $params['horizAlign'] );
		}
		if ( $params['vertAlign'] ) {
			$params['frame']['valign'] = key( $params['vertAlign'] );
		}

		$params['frame']['caption'] = $caption;

		# Will the image be presented in a frame, with the caption below?
		$imageIsFramed = isset( $params['frame']['frame'] ) ||
						 isset( $params['frame']['framed'] ) ||
						 isset( $params['frame']['thumbnail'] ) ||
						 isset( $params['frame']['manualthumb'] );

		# In the old days, [[Image:Foo|text...]] would set alt text.  Later it
		# came to also set the caption, ordinary text after the image -- which
		# makes no sense, because that just repeats the text multiple times in
		# screen readers.  It *also* came to set the title attribute.
		#
		# Now that we have an alt attribute, we should not set the alt text to
		# equal the caption: that's worse than useless, it just repeats the
		# text.  This is the framed/thumbnail case.  If there's no caption, we
		# use the unnamed parameter for alt text as well, just for the time be-
		# ing, if the unnamed param is set and the alt param is not.
		#
		# For the future, we need to figure out if we want to tweak this more,
		# e.g., introducing a title= parameter for the title; ignoring the un-
		# named parameter entirely for images without a caption; adding an ex-
		# plicit caption= parameter and preserving the old magic unnamed para-
		# meter for BC; ...
		if ( $imageIsFramed ) { # Framed image
			if ( $caption === '' && !isset( $params['frame']['alt'] ) ) {
				# No caption or alt text, add the filename as the alt text so
				# that screen readers at least get some description of the image
				$params['frame']['alt'] = $title->getText();
			}
			# Do not set $params['frame']['title'] because tooltips don't make sense
			# for framed images
		} else { # Inline image
			if ( !isset( $params['frame']['alt'] ) ) {
				# No alt text, use the "caption" for the alt text
				if ( $caption !== '') {
					$params['frame']['alt'] = $this->stripAltText( $caption, $holders );
				} else {
					# No caption, fall back to using the filename for the
					# alt text
					$params['frame']['alt'] = $title->getText();
				}
			}
			# Use the "caption" for the tooltip text
			$params['frame']['title'] = $this->stripAltText( $caption, $holders );
		}

		wfRunHooks( 'ParserMakeImageParams', array( $title, $file, &$params ) );

		# Linker does the rest
		$ret = Linker::makeImageLink2( $title, $file, $params['frame'], $params['handler'],
			$time, $descQuery, $this->mOptions->getThumbSize() );

		# Give the handler a chance to modify the parser object
		if ( $handler ) {
			$handler->parserTransformHook( $this, $file );
		}

		return $ret;
	}

	/**
	 * @param $caption
	 * @param $holders LinkHolderArray
	 * @return mixed|String
	 */
	protected function stripAltText( $caption, $holders ) {
		# Strip bad stuff out of the title (tooltip).  We can't just use
		# replaceLinkHoldersText() here, because if this function is called
		# from replaceInternalLinks2(), mLinkHolders won't be up-to-date.
		if ( $holders ) {
			$tooltip = $holders->replaceText( $caption );
		} else {
			$tooltip = $this->replaceLinkHoldersText( $caption );
		}

		# make sure there are no placeholders in thumbnail attributes
		# that are later expanded to html- so expand them now and
		# remove the tags
		$tooltip = $this->mStripState->unstripBoth( $tooltip );
		$tooltip = Sanitizer::stripAllTags( $tooltip );

		return $tooltip;
	}

	/**
	 * Set a flag in the output object indicating that the content is dynamic and
	 * shouldn't be cached.
	 */
	function disableCache() {
		wfDebug( "Parser output marked as uncacheable.\n" );
		$this->mOutput->setCacheTime( -1 ); // old style, for compatibility
		$this->mOutput->updateCacheExpiry( 0 ); // new style, for consistency
	}

	/**
	 * Callback from the Sanitizer for expanding items found in HTML attribute
	 * values, so they can be safely tested and escaped.
	 *
	 * @param $text String
	 * @param $frame PPFrame
	 * @return String
	 */
	function attributeStripCallback( &$text, $frame = false ) {
		$text = $this->replaceVariables( $text, $frame );
		$text = $this->mStripState->unstripBoth( $text );
		return $text;
	}

	/**
	 * Accessor
	 *
	 * @return array
	 */
	function getTags() {
		return array_merge( array_keys( $this->mTransparentTagHooks ), array_keys( $this->mTagHooks ) );
	}

	/**
	 * Replace transparent tags in $text with the values given by the callbacks.
	 *
	 * Transparent tag hooks are like regular XML-style tag hooks, except they
	 * operate late in the transformation sequence, on HTML instead of wikitext.
	 */
	function replaceTransparentTags( $text ) {
		$matches = array();
		$elements = array_keys( $this->mTransparentTagHooks );
		$text = self::extractTagsAndParams( $elements, $text, $matches, $this->mUniqPrefix );
		$replacements = array();

		foreach ( $matches as $marker => $data ) {
			list( $element, $content, $params, $tag ) = $data;
			$tagName = strtolower( $element );
			if ( isset( $this->mTransparentTagHooks[$tagName] ) ) {
				$output = call_user_func_array( $this->mTransparentTagHooks[$tagName], array( $content, $params, $this ) );
			} else {
				$output = $tag;
			}
			$replacements[$marker] = $output;
		}
		return strtr( $text, $replacements );
	}

	/**
	 * Break wikitext input into sections, and either pull or replace
	 * some particular section's text.
	 *
	 * External callers should use the getSection and replaceSection methods.
	 *
	 * @param $text String: Page wikitext
	 * @param $section String: a section identifier string of the form:
	 *    -  - ... - 

	 *
	 * Currently the only recognised flag is "T", which means the target section number
	 * was derived during a template inclusion parse, in other words this is a template
	 * section edit link. If no flags are given, it was an ordinary section edit link.
	 * This flag is required to avoid a section numbering mismatch when a section is
	 * enclosed by  (bug 6563).
	 *
	 * The section number 0 pulls the text before the first heading; other numbers will
	 * pull the given section along with its lower-level subsections. If the section is
	 * not found, $mode=get will return $newtext, and $mode=replace will return $text.
	 *
	 * Section 0 is always considered to exist, even if it only contains the empty
	 * string. If $text is the empty string and section 0 is replaced, $newText is 
	 * returned.
	 *
	 * @param $mode String: one of "get" or "replace"
	 * @param $newText String: replacement text for section data.
	 * @return String: for "get", the extracted section text.
	 *                 for "replace", the whole page with the section replaced.
	 */
	private function extractSections( $text, $section, $mode, $newText='' ) {
		global $wgTitle; # not generally used but removes an ugly failure mode
		$this->startParse( $wgTitle, new ParserOptions, self::OT_PLAIN, true );
		$outText = '';
		$frame = $this->getPreprocessor()->newFrame();

		# Process section extraction flags
		$flags = 0;
		$sectionParts = explode( '-', $section );
		$sectionIndex = array_pop( $sectionParts );
		foreach ( $sectionParts as $part ) {
			if ( $part === 'T' ) {
				$flags |= self::PTD_FOR_INCLUSION;
			}
		}

		# Check for empty input
		if ( strval( $text ) === '' ) {
			# Only sections 0 and T-0 exist in an empty document
			if ( $sectionIndex == 0 ) {
				if ( $mode === 'get' ) {
					return '';
				} else {
					return $newText;
				}
			} else {
				if ( $mode === 'get' ) {
					return $newText;
				} else {
					return $text;
				}
			}
		}

		# Preprocess the text
		$root = $this->preprocessToDom( $text, $flags );

		#  nodes indicate section breaks
		# They can only occur at the top level, so we can find them by iterating the root's children
		$node = $root->getFirstChild();

		# Find the target section
		if ( $sectionIndex == 0 ) {
			# Section zero doesn't nest, level=big
			$targetLevel = 1000;
		} else {
			while ( $node ) {
				if ( $node->getName() === 'h' ) {
					$bits = $node->splitHeading();
					if ( $bits['i'] == $sectionIndex ) {
						$targetLevel = $bits['level'];
						break;
					}
				}
				if ( $mode === 'replace' ) {
					$outText .= $frame->expand( $node, PPFrame::RECOVER_ORIG );
				}
				$node = $node->getNextSibling();
			}
		}

		if ( !$node ) {
			# Not found
			if ( $mode === 'get' ) {
				return $newText;
			} else {
				return $text;
			}
		}

		# Find the end of the section, including nested sections
		do {
			if ( $node->getName() === 'h' ) {
				$bits = $node->splitHeading();
				$curLevel = $bits['level'];
				if ( $bits['i'] != $sectionIndex && $curLevel <= $targetLevel ) {
					break;
				}
			}
			if ( $mode === 'get' ) {
				$outText .= $frame->expand( $node, PPFrame::RECOVER_ORIG );
			}
			$node = $node->getNextSibling();
		} while ( $node );

		# Write out the remainder (in replace mode only)
		if ( $mode === 'replace' ) {
			# Output the replacement text
			# Add two newlines on -- trailing whitespace in $newText is conventionally
			# stripped by the editor, so we need both newlines to restore the paragraph gap
			# Only add trailing whitespace if there is newText
			if ( $newText != "" ) {
				$outText .= $newText . "\n\n";
			}

			while ( $node ) {
				$outText .= $frame->expand( $node, PPFrame::RECOVER_ORIG );
				$node = $node->getNextSibling();
			}
		}

		if ( is_string( $outText ) ) {
			# Re-insert stripped tags
			$outText = rtrim( $this->mStripState->unstripBoth( $outText ) );
		}

		return $outText;
	}

	/**
	 * This function returns the text of a section, specified by a number ($section).
	 * A section is text under a heading like == Heading == or \Heading\, or
	 * the first section before any such heading (section 0).
	 *
	 * If a section contains subsections, these are also returned.
	 *
	 * @param $text String: text to look in
	 * @param $section String: section identifier
	 * @param $deftext String: default to return if section is not found
	 * @return string text of the requested section
	 */
	public function getSection( $text, $section, $deftext='' ) {
		return $this->extractSections( $text, $section, "get", $deftext );
	}

	/**
	 * This function returns $oldtext after the content of the section
	 * specified by $section has been replaced with $text. If the target 
	 * section does not exist, $oldtext is returned unchanged.
	 *
	 * @param $oldtext String: former text of the article
	 * @param $section Numeric: section identifier
	 * @param $text String: replacing text
	 * @return String: modified text
	 */
	public function replaceSection( $oldtext, $section, $text ) {
		return $this->extractSections( $oldtext, $section, "replace", $text );
	}

	/**
	 * Get the ID of the revision we are parsing
	 *
	 * @return Mixed: integer or null
	 */
	function getRevisionId() {
		return $this->mRevisionId;
	}

	/**
	 * Get the revision object for $this->mRevisionId
	 *
	 * @return Revision|null either a Revision object or null
	 */
	protected function getRevisionObject() {
		if ( !is_null( $this->mRevisionObject ) ) {
			return $this->mRevisionObject;
		}
		if ( is_null( $this->mRevisionId ) ) {
			return null;
		}

		$this->mRevisionObject = Revision::newFromId( $this->mRevisionId );
		return $this->mRevisionObject;
	}

	/**
	 * Get the timestamp associated with the current revision, adjusted for
	 * the default server-local timestamp
	 */
	function getRevisionTimestamp() {
		if ( is_null( $this->mRevisionTimestamp ) ) {
			wfProfileIn( __METHOD__ );

			global $wgContLang;

			$revObject = $this->getRevisionObject();
			$timestamp = $revObject ? $revObject->getTimestamp() : wfTimestampNow();

			# The cryptic '' timezone parameter tells to use the site-default
			# timezone offset instead of the user settings.
			#
			# Since this value will be saved into the parser cache, served
			# to other users, and potentially even used inside links and such,
			# it needs to be consistent for all visitors.
			$this->mRevisionTimestamp = $wgContLang->userAdjust( $timestamp, '' );

			wfProfileOut( __METHOD__ );
		}
		return $this->mRevisionTimestamp;
	}

	/**
	 * Get the name of the user that edited the last revision
	 *
	 * @return String: user name
	 */
	function getRevisionUser() {
		if( is_null( $this->mRevisionUser ) ) {
			$revObject = $this->getRevisionObject();

			# if this template is subst: the revision id will be blank,
			# so just use the current user's name
			if( $revObject ) {
				$this->mRevisionUser = $revObject->getUserText();
			} elseif( $this->ot['wiki'] || $this->mOptions->getIsPreview() ) {
				$this->mRevisionUser = $this->getUser()->getName();
			}
		}
		return $this->mRevisionUser;
	}

	/**
	 * Mutator for $mDefaultSort
	 *
	 * @param $sort New value
	 */
	public function setDefaultSort( $sort ) {
		$this->mDefaultSort = $sort;
		$this->mOutput->setProperty( 'defaultsort', $sort );
	}

	/**
	 * Accessor for $mDefaultSort
	 * Will use the empty string if none is set.
	 *
	 * This value is treated as a prefix, so the
	 * empty string is equivalent to sorting by
	 * page name.
	 *
	 * @return string
	 */
	public function getDefaultSort() {
		if ( $this->mDefaultSort !== false ) {
			return $this->mDefaultSort;
		} else {
			return '';
		}
	}

	/**
	 * Accessor for $mDefaultSort
	 * Unlike getDefaultSort(), will return false if none is set
	 *
	 * @return string or false
	 */
	public function getCustomDefaultSort() {
		return $this->mDefaultSort;
	}

	/**
	 * Try to guess the section anchor name based on a wikitext fragment
	 * presumably extracted from a heading, for example "Header" from
	 * "== Header ==".
	 */
	public function guessSectionNameFromWikiText( $text ) {
		# Strip out wikitext links(they break the anchor)
		$text = $this->stripSectionName( $text );
		$text = Sanitizer::normalizeSectionNameWhitespace( $text );
		return '#' . Sanitizer::escapeId( $text, 'noninitial' );
	}

	/**
	 * Same as guessSectionNameFromWikiText(), but produces legacy anchors
	 * instead.  For use in redirects, since IE6 interprets Redirect: headers
	 * as something other than UTF-8 (apparently?), resulting in breakage.
	 *
	 * @param $text String: The section name
	 * @return string An anchor
	 */
	public function guessLegacySectionNameFromWikiText( $text ) {
		# Strip out wikitext links(they break the anchor)
		$text = $this->stripSectionName( $text );
		$text = Sanitizer::normalizeSectionNameWhitespace( $text );
		return '#' . Sanitizer::escapeId( $text, array( 'noninitial', 'legacy' ) );
	}

	/**
	 * Strips a text string of wikitext for use in a section anchor
	 *
	 * Accepts a text string and then removes all wikitext from the
	 * string and leaves only the resultant text (i.e. the result of
	 * [[User:WikiSysop|Sysop]] would be "Sysop" and the result of
	 * [[User:WikiSysop]] would be "User:WikiSysop") - this is intended
	 * to create valid section anchors by mimicing the output of the
	 * parser when headings are parsed.
	 *
	 * @param $text String: text string to be stripped of wikitext
	 * for use in a Section anchor
	 * @return Filtered text string
	 */
	public function stripSectionName( $text ) {
		# Strip internal link markup
		$text = preg_replace( '/\[\[:?([^[|]+)\|([^[]+)\]\]/', '$2', $text );
		$text = preg_replace( '/\[\[:?([^[]+)\|?\]\]/', '$1', $text );

		# Strip external link markup
		# @todo FIXME: Not tolerant to blank link text
		# I.E. [http://www.mediawiki.org] will render as [1] or something depending
		# on how many empty links there are on the page - need to figure that out.
		$text = preg_replace( '/\[(?:' . wfUrlProtocols() . ')([^ ]+?) ([^[]+)\]/', '$2', $text );

		# Parse wikitext quotes (italics & bold)
		$text = $this->doQuotes( $text );

		# Strip HTML tags
		$text = StringUtils::delimiterReplace( '<', '>', '', $text );
		return $text;
	}

	/**
	 * strip/replaceVariables/unstrip for preprocessor regression testing
	 *
	 * @return string
	 */
	function testSrvus( $text, Title $title, ParserOptions $options, $outputType = self::OT_HTML ) {
		$this->startParse( $title, $options, $outputType, true );

		$text = $this->replaceVariables( $text );
		$text = $this->mStripState->unstripBoth( $text );
		$text = Sanitizer::removeHTMLtags( $text );
		return $text;
	}

	function testPst( $text, Title $title, ParserOptions $options ) {
		return $this->preSaveTransform( $text, $title, $options->getUser(), $options );
	}

	function testPreprocess( $text, Title $title, ParserOptions $options ) {
		return $this->testSrvus( $text, $title, $options, self::OT_PREPROCESS );
	}

	/**
	 * Call a callback function on all regions of the given text that are not
	 * inside strip markers, and replace those regions with the return value
	 * of the callback. For example, with input:
	 *
	 *  aaabbb
	 *
	 * This will call the callback function twice, with 'aaa' and 'bbb'. Those
	 * two strings will be replaced with the value returned by the callback in
	 * each case.
	 *
	 * @return string
	 */
	function markerSkipCallback( $s, $callback ) {
		$i = 0;
		$out = '';
		while ( $i < strlen( $s ) ) {
			$markerStart = strpos( $s, $this->mUniqPrefix, $i );
			if ( $markerStart === false ) {
				$out .= call_user_func( $callback, substr( $s, $i ) );
				break;
			} else {
				$out .= call_user_func( $callback, substr( $s, $i, $markerStart - $i ) );
				$markerEnd = strpos( $s, self::MARKER_SUFFIX, $markerStart );
				if ( $markerEnd === false ) {
					$out .= substr( $s, $markerStart );
					break;
				} else {
					$markerEnd += strlen( self::MARKER_SUFFIX );
					$out .= substr( $s, $markerStart, $markerEnd - $markerStart );
					$i = $markerEnd;
				}
			}
		}
		return $out;
	}

	/**
	 * Save the parser state required to convert the given half-parsed text to
	 * HTML. "Half-parsed" in this context means the output of
	 * recursiveTagParse() or internalParse(). This output has strip markers
	 * from replaceVariables (extensionSubstitution() etc.), and link
	 * placeholders from replaceLinkHolders().
	 *
	 * Returns an array which can be serialized and stored persistently. This
	 * array can later be loaded into another parser instance with
	 * unserializeHalfParsedText(). The text can then be safely incorporated into
	 * the return value of a parser hook.
	 *
	 * @return array
	 */
	function serializeHalfParsedText( $text ) {
		wfProfileIn( __METHOD__ );
		$data = array(
			'text' => $text,
			'version' => self::HALF_PARSED_VERSION,
			'stripState' => $this->mStripState->getSubState( $text ),
			'linkHolders' => $this->mLinkHolders->getSubArray( $text )
		);
		wfProfileOut( __METHOD__ );
		return $data;
	}

	/**
	 * Load the parser state given in the $data array, which is assumed to
	 * have been generated by serializeHalfParsedText(). The text contents is
	 * extracted from the array, and its markers are transformed into markers
	 * appropriate for the current Parser instance. This transformed text is
	 * returned, and can be safely included in the return value of a parser
	 * hook.
	 *
	 * If the $data array has been stored persistently, the caller should first
	 * check whether it is still valid, by calling isValidHalfParsedText().
	 *
	 * @param $data Serialized data
	 * @return String
	 */
	function unserializeHalfParsedText( $data ) {
		if ( !isset( $data['version'] ) || $data['version'] != self::HALF_PARSED_VERSION ) {
			throw new MWException( __METHOD__.': invalid version' );
		}

		# First, extract the strip state.
		$texts = array( $data['text'] );
		$texts = $this->mStripState->merge( $data['stripState'], $texts );

		# Now renumber links
		$texts = $this->mLinkHolders->mergeForeign( $data['linkHolders'], $texts );

		# Should be good to go.
		return $texts[0];
	}

	/**
	 * Returns true if the given array, presumed to be generated by
	 * serializeHalfParsedText(), is compatible with the current version of the
	 * parser.
	 *
	 * @param $data Array
	 *
	 * @return bool
	 */
	function isValidHalfParsedText( $data ) {
		return isset( $data['version'] ) && $data['version'] == self::HALF_PARSED_VERSION;
	}
}