update to MediaWiki 1.16.0

8 files changed, 2889 insertions, 0 deletions

diff --git a/includes/search/SearchEngine.php b/includes/search/SearchEngine.php
new file mode 100644
index 00000000..f4ca700d
--- /dev/null
+++ b/includes/search/SearchEngine.php
@@ -0,0 +1,1248 @@
+<?php
+/**
+ * @defgroup Search Search
+ *
+ * @file
+ * @ingroup Search
+ */
+
+/**
+ * Contain a class for special pages
+ * @ingroup Search
+ */
+class SearchEngine {
+	var $limit = 10;
+	var $offset = 0;
+	var $prefix = '';
+	var $searchTerms = array();
+	var $namespaces = array( NS_MAIN );
+	var $showRedirects = false;
+
+	/**
+	 * Perform a full text search query and return a result set.
+	 * If title searches are not supported or disabled, return null.
+	 * STUB
+	 *
+	 * @param $term String: raw search term
+	 * @return SearchResultSet
+	 */
+	function searchText( $term ) {
+		return null;
+	}
+
+	/**
+	 * Perform a title-only search query and return a result set.
+	 * If title searches are not supported or disabled, return null.
+	 * STUB
+	 *
+	 * @param $term String: raw search term
+	 * @return SearchResultSet
+	 */
+	function searchTitle( $term ) {
+		return null;
+	}
+	
+	/** If this search backend can list/unlist redirects */
+	function acceptListRedirects() {
+		return true;
+	}
+	
+	/**
+	 * When overridden in derived class, performs database-specific conversions
+	 * on text to be used for searching or updating search index.
+	 * Default implementation does nothing (simply returns $string).
+	 *
+	 * @param $string string: String to process
+	 * @return string
+	 */
+	public function normalizeText( $string ) {
+		return $string;
+	}
+
+	/**
+	 * Transform search term in cases when parts of the query came as different GET params (when supported)
+	 * e.g. for prefix queries: search=test&prefix=Main_Page/Archive -> test prefix:Main Page/Archive
+	 */
+	function transformSearchTerm( $term ) {
+		return $term;
+	}
+	
+	/**
+	 * If an exact title match can be found, or a very slightly close match,
+	 * return the title. If no match, returns NULL.
+	 *
+	 * @param $searchterm String
+	 * @return Title
+	 */
+	public static function getNearMatch( $searchterm ) {
+		$title = self::getNearMatchInternal( $searchterm );
+		
+		wfRunHooks( 'SearchGetNearMatchComplete', array( $searchterm, &$title ) );
+		return $title;
+	}
+	
+	/**
+	 * Really find the title match.
+	 */
+	private static function getNearMatchInternal( $searchterm ) {
+		global $wgContLang;
+
+		$allSearchTerms = array($searchterm);
+
+		if ( $wgContLang->hasVariants() ) {
+			$allSearchTerms = array_merge($allSearchTerms,$wgContLang->convertLinkToAllVariants($searchterm));
+		}
+
+		if( !wfRunHooks( 'SearchGetNearMatchBefore', array( $allSearchTerms, &$titleResult ) ) ) {
+			return $titleResult;
+		}
+
+		foreach($allSearchTerms as $term) {
+
+			# Exact match? No need to look further.
+			$title = Title::newFromText( $term );
+			if (is_null($title))
+				return null;
+
+			if ( $title->getNamespace() == NS_SPECIAL || $title->isExternal() || $title->exists() ) {
+				return $title;
+			}
+			
+			# See if it still otherwise has content is some sane sense
+			$article = MediaWiki::articleFromTitle( $title );
+			if( $article->hasViewableContent() ) {
+				return $title;
+			}
+
+			# Now try all lower case (i.e. first letter capitalized)
+			#
+			$title = Title::newFromText( $wgContLang->lc( $term ) );
+			if ( $title && $title->exists() ) {
+				return $title;
+			}
+
+			# Now try capitalized string
+			#
+			$title = Title::newFromText( $wgContLang->ucwords( $term ) );
+			if ( $title && $title->exists() ) {
+				return $title;
+			}
+
+			# Now try all upper case
+			#
+			$title = Title::newFromText( $wgContLang->uc( $term ) );
+			if ( $title && $title->exists() ) {
+				return $title;
+			}
+
+			# Now try Word-Caps-Breaking-At-Word-Breaks, for hyphenated names etc
+			$title = Title::newFromText( $wgContLang->ucwordbreaks($term) );
+			if ( $title && $title->exists() ) {
+				return $title;
+			}
+
+			// Give hooks a chance at better match variants
+			$title = null;
+			if( !wfRunHooks( 'SearchGetNearMatch', array( $term, &$title ) ) ) {
+				return $title;
+			}
+		}
+
+		$title = Title::newFromText( $searchterm );
+
+		# Entering an IP address goes to the contributions page
+		if ( ( $title->getNamespace() == NS_USER && User::isIP($title->getText() ) )
+			|| User::isIP( trim( $searchterm ) ) ) {
+			return SpecialPage::getTitleFor( 'Contributions', $title->getDBkey() );
+		}
+
+
+		# Entering a user goes to the user page whether it's there or not
+		if ( $title->getNamespace() == NS_USER ) {
+			return $title;
+		}
+
+		# Go to images that exist even if there's no local page.
+		# There may have been a funny upload, or it may be on a shared
+		# file repository such as Wikimedia Commons.
+		if( $title->getNamespace() == NS_FILE ) {
+			$image = wfFindFile( $title );
+			if( $image ) {
+				return $title;
+			}
+		}
+
+		# MediaWiki namespace? Page may be "implied" if not customized.
+		# Just return it, with caps forced as the message system likes it.
+		if( $title->getNamespace() == NS_MEDIAWIKI ) {
+			return Title::makeTitle( NS_MEDIAWIKI, $wgContLang->ucfirst( $title->getText() ) );
+		}
+
+		# Quoted term? Try without the quotes...
+		$matches = array();
+		if( preg_match( '/^"([^"]+)"$/', $searchterm, $matches ) ) {
+			return SearchEngine::getNearMatch( $matches[1] );
+		}
+
+		return null;
+	}
+
+	public static function legalSearchChars() {
+		return "A-Za-z_'.0-9\\x80-\\xFF\\-";
+	}
+
+	/**
+	 * Set the maximum number of results to return
+	 * and how many to skip before returning the first.
+	 *
+	 * @param $limit Integer
+	 * @param $offset Integer
+	 */
+	function setLimitOffset( $limit, $offset = 0 ) {
+		$this->limit = intval( $limit );
+		$this->offset = intval( $offset );
+	}
+
+	/**
+	 * Set which namespaces the search should include.
+	 * Give an array of namespace index numbers.
+	 *
+	 * @param $namespaces Array
+	 */
+	function setNamespaces( $namespaces ) {
+		$this->namespaces = $namespaces;
+	}
+
+	/**
+	 * Parse some common prefixes: all (search everything)
+	 * or namespace names
+	 *
+	 * @param $query String
+	 */
+	function replacePrefixes( $query ){
+		global $wgContLang;
+
+		$parsed = $query;
+		if( strpos($query,':') === false ) { // nothing to do
+			wfRunHooks( 'SearchEngineReplacePrefixesComplete', array( $this, $query, &$parsed ) );
+			return $parsed;
+		}
+		
+		$allkeyword = wfMsgForContent('searchall').":";
+		if( strncmp($query, $allkeyword, strlen($allkeyword)) == 0 ){
+			$this->namespaces = null;
+			$parsed = substr($query,strlen($allkeyword));
+		} else if( strpos($query,':') !== false ) {
+			$prefix = substr($query,0,strpos($query,':'));
+			$index = $wgContLang->getNsIndex($prefix);
+			if($index !== false){
+				$this->namespaces = array($index);
+				$parsed = substr($query,strlen($prefix)+1);
+			}
+		}
+		if(trim($parsed) == '')
+			$parsed = $query; // prefix was the whole query
+
+		wfRunHooks( 'SearchEngineReplacePrefixesComplete', array( $this, $query, &$parsed ) );
+
+		return $parsed;
+	}
+
+	/**
+	 * Make a list of searchable namespaces and their canonical names.
+	 * @return Array
+	 */
+	public static function searchableNamespaces() {
+		global $wgContLang;
+		$arr = array();
+		foreach( $wgContLang->getNamespaces() as $ns => $name ) {
+			if( $ns >= NS_MAIN ) {
+				$arr[$ns] = $name;
+			}
+		}
+		
+		wfRunHooks( 'SearchableNamespaces', array( &$arr ) );
+		return $arr;
+	}
+	
+	/**
+	 * Extract default namespaces to search from the given user's
+	 * settings, returning a list of index numbers.
+	 *
+	 * @param $user User
+	 * @return Array
+	 */
+	public static function userNamespaces( $user ) {
+		global $wgSearchEverythingOnlyLoggedIn;
+		
+		// get search everything preference, that can be set to be read for logged-in users
+		$searcheverything = false;
+		if( ( $wgSearchEverythingOnlyLoggedIn && $user->isLoggedIn() )
+		    || !$wgSearchEverythingOnlyLoggedIn )
+			$searcheverything = $user->getOption('searcheverything');
+		
+		// searcheverything overrides other options 
+		if( $searcheverything )
+			return array_keys(SearchEngine::searchableNamespaces());
+		
+		$arr = Preferences::loadOldSearchNs( $user );
+		$searchableNamespaces = SearchEngine::searchableNamespaces();
+		
+		$arr = array_intersect( $arr, array_keys($searchableNamespaces) ); // Filter
+		
+		return $arr;
+	}
+	
+	/**
+	 * Find snippet highlight settings for a given user
+	 *
+	 * @param $user User
+	 * @return Array contextlines, contextchars 
+	 */
+	public static function userHighlightPrefs( &$user ){
+		//$contextlines = $user->getOption( 'contextlines',  5 );
+		//$contextchars = $user->getOption( 'contextchars', 50 );
+		$contextlines = 2; // Hardcode this. Old defaults sucked. :)
+		$contextchars = 75; // same as above.... :P
+		return array($contextlines, $contextchars);
+	}
+	
+	/**
+	 * An array of namespaces indexes to be searched by default
+	 * 
+	 * @return Array 
+	 */
+	public static function defaultNamespaces(){
+		global $wgNamespacesToBeSearchedDefault;
+		
+		return array_keys($wgNamespacesToBeSearchedDefault, true);
+	}
+	
+	/**
+	 * Get a list of namespace names useful for showing in tooltips
+	 * and preferences
+	 *
+	 * @param $namespaces Array
+	 */
+	public static function namespacesAsText( $namespaces ){
+		global $wgContLang;
+		
+		$formatted = array_map( array($wgContLang,'getFormattedNsText'), $namespaces );
+		foreach( $formatted as $key => $ns ){
+			if ( empty($ns) )
+				$formatted[$key] = wfMsg( 'blanknamespace' );
+		}
+		return $formatted;
+	}
+	
+	/**
+	 * Return the help namespaces to be shown on Special:Search
+	 * 
+	 * @return Array 
+	 */
+	public static function helpNamespaces() {
+		global $wgNamespacesToBeSearchedHelp;
+		
+		return array_keys( $wgNamespacesToBeSearchedHelp, true );
+	}
+	
+	/**
+	 * Return a 'cleaned up' search string
+	 *
+	 * @param $text String
+	 * @return String
+	 */
+	function filter( $text ) {
+		$lc = $this->legalSearchChars();
+		return trim( preg_replace( "/[^{$lc}]/", " ", $text ) );
+	}
+	/**
+	 * Load up the appropriate search engine class for the currently
+	 * active database backend, and return a configured instance.
+	 *
+	 * @return SearchEngine
+	 */
+	public static function create() {
+		global $wgSearchType;
+		$dbr = wfGetDB( DB_SLAVE );
+		if( $wgSearchType ) {
+			$class = $wgSearchType;
+		} else {
+			$class = $dbr->getSearchEngine();
+		}
+		$search = new $class( $dbr );
+		$search->setLimitOffset(0,0);
+		return $search;
+	}
+
+	/**
+	 * Create or update the search index record for the given page.
+	 * Title and text should be pre-processed.
+	 * STUB
+	 *
+	 * @param $id Integer
+	 * @param $title String
+	 * @param $text String
+	 */
+	function update( $id, $title, $text ) {
+		// no-op
+	}
+
+	/**
+	 * Update a search index record's title only.
+	 * Title should be pre-processed.
+	 * STUB
+	 *
+	 * @param $id Integer
+	 * @param $title String
+	 */
+	function updateTitle( $id, $title ) {
+		// no-op
+	}
+	
+	/**
+	 * Get OpenSearch suggestion template
+	 * 
+	 * @return String
+	 */
+	public static function getOpenSearchTemplate() {
+		global $wgOpenSearchTemplate, $wgServer, $wgScriptPath;
+		if( $wgOpenSearchTemplate )	{	
+			return $wgOpenSearchTemplate;
+		} else { 
+			$ns = implode( '|', SearchEngine::defaultNamespaces() );
+			if( !$ns ) $ns = "0";
+			return $wgServer . $wgScriptPath . '/api.php?action=opensearch&search={searchTerms}&namespace='.$ns;
+		}
+	}
+	
+	/**
+	 * Get internal MediaWiki Suggest template 
+	 * 
+	 * @return String
+	 */
+	public static function getMWSuggestTemplate() {
+		global $wgMWSuggestTemplate, $wgServer, $wgScriptPath;
+		if($wgMWSuggestTemplate)		
+			return $wgMWSuggestTemplate;
+		else 
+			return $wgServer . $wgScriptPath . '/api.php?action=opensearch&search={searchTerms}&namespace={namespaces}&suggest';
+	}
+}
+
+/**
+ * @ingroup Search
+ */
+class SearchResultSet {
+	/**
+	 * Fetch an array of regular expression fragments for matching
+	 * the search terms as parsed by this engine in a text extract.
+	 * STUB
+	 *
+	 * @return Array
+	 */
+	function termMatches() {
+		return array();
+	}
+
+	function numRows() {
+		return 0;
+	}
+
+	/**
+	 * Return true if results are included in this result set.
+	 * STUB
+	 *
+	 * @return Boolean
+	 */
+	function hasResults() {
+		return false;
+	}
+
+	/**
+	 * Some search modes return a total hit count for the query
+	 * in the entire article database. This may include pages
+	 * in namespaces that would not be matched on the given
+	 * settings.
+	 *
+	 * Return null if no total hits number is supported.
+	 *
+	 * @return Integer
+	 */
+	function getTotalHits() {
+		return null;
+	}
+
+	/**
+	 * Some search modes return a suggested alternate term if there are
+	 * no exact hits. Returns true if there is one on this set.
+	 *
+	 * @return Boolean
+	 */
+	function hasSuggestion() {
+		return false;
+	}
+
+	/**
+	 * @return String: suggested query, null if none
+	 */
+	function getSuggestionQuery(){
+		return null;
+	}
+
+	/**
+	 * @return String: HTML highlighted suggested query, '' if none
+	 */
+	function getSuggestionSnippet(){
+		return '';
+	}
+	
+	/**
+	 * Return information about how and from where the results were fetched,
+	 * should be useful for diagnostics and debugging 
+	 *
+	 * @return String
+	 */
+	function getInfo() {
+		return null;
+	}
+	
+	/**
+	 * Return a result set of hits on other (multiple) wikis associated with this one
+	 *
+	 * @return SearchResultSet
+	 */
+	function getInterwikiResults() {
+		return null;
+	}
+	
+	/**
+	 * Check if there are results on other wikis
+	 *
+	 * @return Boolean
+	 */
+	function hasInterwikiResults() {
+		return $this->getInterwikiResults() != null;
+	}
+	
+
+	/**
+	 * Fetches next search result, or false.
+	 * STUB
+	 *
+	 * @return SearchResult
+	 */
+	function next() {
+		return false;
+	}
+
+	/**
+	 * Frees the result set, if applicable.
+	 */
+	function free() {
+		// ...
+	}
+}
+
+/**
+ * This class is used for different SQL-based search engines shipped with MediaWiki
+ */
+class SqlSearchResultSet extends SearchResultSet {
+	function __construct( $resultSet, $terms ) {
+		$this->mResultSet = $resultSet;
+		$this->mTerms = $terms;
+	}
+
+	function termMatches() {
+		return $this->mTerms;
+	}
+
+	function numRows() {
+		return $this->mResultSet->numRows();
+	}
+
+	function next() {
+		if ($this->mResultSet === false )
+			return false;
+
+		$row = $this->mResultSet->fetchObject();
+		if ($row === false)
+			return false;
+		return new SearchResult($row);
+	}
+
+	function free() {
+		$this->mResultSet->free();
+	}
+}
+
+/**
+ * @ingroup Search
+ */
+class SearchResultTooMany {
+	## Some search engines may bail out if too many matches are found
+}
+
+
+/**
+ * @todo Fixme: This class is horribly factored. It would probably be better to
+ * have a useful base class to which you pass some standard information, then
+ * let the fancy self-highlighters extend that.
+ * @ingroup Search
+ */
+class SearchResult {
+	var $mRevision = null;
+	var $mImage = null;
+
+	function __construct( $row ) {
+		$this->mTitle = Title::makeTitle( $row->page_namespace, $row->page_title );
+		if( !is_null($this->mTitle) ){
+			$this->mRevision = Revision::newFromTitle( $this->mTitle );
+			if( $this->mTitle->getNamespace() === NS_FILE )
+				$this->mImage = wfFindFile( $this->mTitle );
+		}
+	}
+	
+	/**
+	 * Check if this is result points to an invalid title
+	 *
+	 * @return Boolean
+	 */
+	function isBrokenTitle(){
+		if( is_null($this->mTitle) )
+			return true;
+		return false;
+	}
+	
+	/**
+	 * Check if target page is missing, happens when index is out of date
+	 * 
+	 * @return Boolean
+	 */
+	function isMissingRevision(){
+		return !$this->mRevision && !$this->mImage;
+	}
+
+	/**
+	 * @return Title
+	 */
+	function getTitle() {
+		return $this->mTitle;
+	}
+
+	/**
+	 * @return Double or null if not supported
+	 */
+	function getScore() {
+		return null;
+	}
+
+	/**
+	 * Lazy initialization of article text from DB
+	 */
+	protected function initText(){
+		if( !isset($this->mText) ){
+			if($this->mRevision != null)
+				$this->mText = $this->mRevision->getText();
+			else // TODO: can we fetch raw wikitext for commons images?
+				$this->mText = '';
+			
+		}
+	}
+	
+	/**
+	 * @param $terms Array: terms to highlight
+	 * @return String: highlighted text snippet, null (and not '') if not supported 
+	 */
+	function getTextSnippet($terms){
+		global $wgUser, $wgAdvancedSearchHighlighting;
+		$this->initText();
+		list($contextlines,$contextchars) = SearchEngine::userHighlightPrefs($wgUser);
+		$h = new SearchHighlighter();
+		if( $wgAdvancedSearchHighlighting )
+			return $h->highlightText( $this->mText, $terms, $contextlines, $contextchars );
+		else
+			return $h->highlightSimple( $this->mText, $terms, $contextlines, $contextchars );
+	}
+	
+	/**
+	 * @param $terms Array: terms to highlight
+	 * @return String: highlighted title, '' if not supported
+	 */
+	function getTitleSnippet($terms){
+		return '';
+	}
+
+	/**
+	 * @param $terms Array: terms to highlight
+	 * @return String: highlighted redirect name (redirect to this page), '' if none or not supported
+	 */
+	function getRedirectSnippet($terms){
+		return '';
+	}
+
+	/**
+	 * @return Title object for the redirect to this page, null if none or not supported
+	 */
+	function getRedirectTitle(){
+		return null;
+	}
+
+	/**
+	 * @return string highlighted relevant section name, null if none or not supported
+	 */
+	function getSectionSnippet(){
+		return '';
+	}
+
+	/**
+	 * @return Title object (pagename+fragment) for the section, null if none or not supported
+	 */
+	function getSectionTitle(){
+		return null;
+	}
+
+	/**
+	 * @return String: timestamp
+	 */
+	function getTimestamp(){
+		if( $this->mRevision )
+			return $this->mRevision->getTimestamp();
+		else if( $this->mImage )
+			return $this->mImage->getTimestamp();
+		return '';			
+	}
+
+	/**
+	 * @return Integer: number of words
+	 */
+	function getWordCount(){
+		$this->initText();
+		return str_word_count( $this->mText );
+	}
+
+	/**
+	 * @return Integer: size in bytes
+	 */
+	function getByteSize(){
+		$this->initText();
+		return strlen( $this->mText );
+	}
+	
+	/**
+	 * @return Boolean if hit has related articles
+	 */
+	function hasRelated(){
+		return false;
+	}
+	
+	/**
+	 * @return String: interwiki prefix of the title (return iw even if title is broken)
+	 */
+	function getInterwikiPrefix(){
+		return '';
+	}
+}
+
+/**
+ * Highlight bits of wikitext
+ * 
+ * @ingroup Search
+ */
+class SearchHighlighter {	
+	var $mCleanWikitext = true;
+	
+	function SearchHighlighter($cleanupWikitext = true){
+		$this->mCleanWikitext = $cleanupWikitext;
+	}
+	
+	/**
+	 * Default implementation of wikitext highlighting
+	 *
+	 * @param $text String
+	 * @param $terms Array: terms to highlight (unescaped)
+	 * @param $contextlines Integer
+	 * @param $contextchars Integer
+	 * @return String
+	 */
+	public function highlightText( $text, $terms, $contextlines, $contextchars ) {
+		global $wgLang, $wgContLang;
+		global $wgSearchHighlightBoundaries;
+		$fname = __METHOD__;
+		
+		if($text == '')
+			return '';
+				
+		// spli text into text + templates/links/tables
+		$spat = "/(\\{\\{)|(\\[\\[[^\\]:]+:)|(\n\\{\\|)";
+		// first capture group is for detecting nested templates/links/tables/references
+		$endPatterns = array(
+			1 => '/(\{\{)|(\}\})/', // template
+			2 => '/(\[\[)|(\]\])/', // image
+			3 => "/(\n\\{\\|)|(\n\\|\\})/"); // table
+			 
+		// FIXME: this should prolly be a hook or something
+		if(function_exists('wfCite')){
+			$spat .= '|(<ref>)'; // references via cite extension
+			$endPatterns[4] = '/(<ref>)|(<\/ref>)/';
+		}
+		$spat .= '/';
+		$textExt = array(); // text extracts
+		$otherExt = array();  // other extracts
+		wfProfileIn( "$fname-split" );
+		$start = 0;
+		$textLen = strlen($text);
+		$count = 0; // sequence number to maintain ordering
+		while( $start < $textLen ){
+			// find start of template/image/table
+			if( preg_match( $spat, $text, $matches, PREG_OFFSET_CAPTURE, $start ) ){
+				$epat = '';	
+				foreach($matches as $key => $val){
+					if($key > 0 && $val[1] != -1){
+						if($key == 2){
+							// see if this is an image link
+							$ns = substr($val[0],2,-1);
+							if( $wgContLang->getNsIndex($ns) != NS_FILE )
+								break;
+							
+						}
+						$epat = $endPatterns[$key];
+						$this->splitAndAdd( $textExt, $count, substr( $text, $start, $val[1] - $start ) );						
+						$start = $val[1];
+						break;
+					}
+				}
+				if( $epat ){
+					// find end (and detect any nested elements)
+					$level = 0; 
+					$offset = $start + 1;
+					$found = false;
+					while( preg_match( $epat, $text, $endMatches, PREG_OFFSET_CAPTURE, $offset ) ){
+						if( array_key_exists(2,$endMatches) ){
+							// found end
+							if($level == 0){
+								$len = strlen($endMatches[2][0]);
+								$off = $endMatches[2][1];
+								$this->splitAndAdd( $otherExt, $count, 
+									substr( $text, $start, $off + $len  - $start ) );
+								$start = $off + $len;
+								$found = true;
+								break;
+							} else{
+								// end of nested element
+								$level -= 1;
+							}
+						} else{
+							// nested
+							$level += 1;
+						}
+						$offset = $endMatches[0][1] + strlen($endMatches[0][0]);
+					}
+					if( ! $found ){
+						// couldn't find appropriate closing tag, skip
+						$this->splitAndAdd( $textExt, $count, substr( $text, $start, strlen($matches[0][0]) ) );
+						$start += strlen($matches[0][0]);
+					}
+					continue;
+				}
+			}
+			// else: add as text extract
+			$this->splitAndAdd( $textExt, $count, substr($text,$start) );
+			break;
+		}
+		
+		$all = $textExt + $otherExt; // these have disjunct key sets
+		
+		wfProfileOut( "$fname-split" );
+		
+		// prepare regexps
+		foreach( $terms as $index => $term ) {
+			// manually do upper/lowercase stuff for utf-8 since PHP won't do it
+			if(preg_match('/[\x80-\xff]/', $term) ){
+				$terms[$index] = preg_replace_callback('/./us',array($this,'caseCallback'),$terms[$index]);
+			} else {
+				$terms[$index] = $term;
+			}
+		}
+		$anyterm = implode( '|', $terms );
+		$phrase = implode("$wgSearchHighlightBoundaries+", $terms );
+
+		// FIXME: a hack to scale contextchars, a correct solution
+		// would be to have contextchars actually be char and not byte
+		// length, and do proper utf-8 substrings and lengths everywhere,
+		// but PHP is making that very hard and unclean to implement :(
+		$scale = strlen($anyterm) / mb_strlen($anyterm);
+		$contextchars = intval( $contextchars * $scale );
+		
+		$patPre = "(^|$wgSearchHighlightBoundaries)";
+		$patPost = "($wgSearchHighlightBoundaries|$)"; 
+		
+		$pat1 = "/(".$phrase.")/ui";
+		$pat2 = "/$patPre(".$anyterm.")$patPost/ui";
+		
+		wfProfileIn( "$fname-extract" );
+		
+		$left = $contextlines;
+
+		$snippets = array();
+		$offsets = array();		
+		
+		// show beginning only if it contains all words
+		$first = 0;
+		$firstText = '';
+		foreach($textExt as $index => $line){
+			if(strlen($line)>0 && $line[0] != ';' && $line[0] != ':'){
+				$firstText = $this->extract( $line, 0, $contextchars * $contextlines );
+				$first = $index;
+				break;
+			}
+		}
+		if( $firstText ){
+			$succ = true;
+			// check if first text contains all terms
+			foreach($terms as $term){
+				if( ! preg_match("/$patPre".$term."$patPost/ui", $firstText) ){
+					$succ = false;
+					break;
+				}
+			}
+			if( $succ ){
+				$snippets[$first] = $firstText;
+				$offsets[$first] = 0; 
+			}
+		}
+		if( ! $snippets ) {		
+			// match whole query on text 
+			$this->process($pat1, $textExt, $left, $contextchars, $snippets, $offsets);
+			// match whole query on templates/tables/images
+			$this->process($pat1, $otherExt, $left, $contextchars, $snippets, $offsets);
+			// match any words on text
+			$this->process($pat2, $textExt, $left, $contextchars, $snippets, $offsets);
+			// match any words on templates/tables/images
+			$this->process($pat2, $otherExt, $left, $contextchars, $snippets, $offsets);
+			
+			ksort($snippets);
+		}
+		
+		// add extra chars to each snippet to make snippets constant size
+		$extended = array();						
+		if( count( $snippets ) == 0){
+			// couldn't find the target words, just show beginning of article
+			$targetchars = $contextchars * $contextlines;
+			$snippets[$first] = '';
+			$offsets[$first] = 0;
+		} else{
+			// if begin of the article contains the whole phrase, show only that !!	
+			if( array_key_exists($first,$snippets) && preg_match($pat1,$snippets[$first]) 
+			    && $offsets[$first] < $contextchars * 2 ){
+				$snippets = array ($first => $snippets[$first]);
+			}
+			
+			// calc by how much to extend existing snippets
+			$targetchars = intval( ($contextchars * $contextlines) / count ( $snippets ) );
+		}  
+
+		foreach($snippets as $index => $line){
+			$extended[$index] = $line;
+			$len = strlen($line);
+			if( $len < $targetchars - 20 ){
+				// complete this line
+				if($len < strlen( $all[$index] )){
+					$extended[$index] = $this->extract( $all[$index], $offsets[$index], $offsets[$index]+$targetchars, $offsets[$index]);
+					$len = strlen( $extended[$index] );
+				}
+				
+				// add more lines
+				$add = $index + 1;
+				while( $len < $targetchars - 20 
+				       && array_key_exists($add,$all) 
+				       && !array_key_exists($add,$snippets) ){
+				    $offsets[$add] = 0;
+				    $tt = "\n".$this->extract( $all[$add], 0, $targetchars - $len, $offsets[$add] );
+					$extended[$add] = $tt;
+					$len += strlen( $tt );
+					$add++; 					
+				}
+			} 
+		}
+		
+		//$snippets = array_map('htmlspecialchars', $extended);
+		$snippets = $extended;
+		$last = -1;
+		$extract = '';
+		foreach($snippets as $index => $line){
+			if($last == -1) 
+				$extract .= $line; // first line
+			elseif($last+1 == $index && $offsets[$last]+strlen($snippets[$last]) >= strlen($all[$last]))
+				$extract .= " ".$line; // continous lines
+			else
+				$extract .= '<b> ... </b>' . $line;
+
+			$last = $index;
+		}
+		if( $extract )
+			$extract .= '<b> ... </b>';
+		
+		$processed = array();
+		foreach($terms as $term){
+			if( ! isset($processed[$term]) ){
+				$pat3 = "/$patPre(".$term.")$patPost/ui"; // highlight word  
+				$extract = preg_replace( $pat3,
+			  		"\\1<span class='searchmatch'>\\2</span>\\3", $extract );
+				$processed[$term] = true;
+			}
+		}
+		
+		wfProfileOut( "$fname-extract" );
+		
+		return $extract;
+	}
+	
+	/**
+	 * Split text into lines and add it to extracts array
+	 *
+	 * @param $extracts Array: index -> $line
+	 * @param $count Integer
+	 * @param $text String
+	 */
+	function splitAndAdd(&$extracts, &$count, $text){
+		$split = explode( "\n", $this->mCleanWikitext? $this->removeWiki($text) : $text );
+		foreach($split as $line){
+			$tt = trim($line);
+			if( $tt )
+				$extracts[$count++] = $tt;
+		}
+	}
+	
+	/**
+	 * Do manual case conversion for non-ascii chars
+	 *
+	 * @param $matches Array
+	 */
+	function caseCallback($matches){
+		global $wgContLang;
+		if( strlen($matches[0]) > 1 ){
+			return '['.$wgContLang->lc($matches[0]).$wgContLang->uc($matches[0]).']';
+		} else
+			return $matches[0];
+	}
+	
+	/**
+	 * Extract part of the text from start to end, but by
+	 * not chopping up words
+	 * @param $text String
+	 * @param $start Integer
+	 * @param $end Integer
+	 * @param $posStart Integer: (out) actual start position
+	 * @param $posEnd Integer: (out) actual end position
+	 * @return String  
+	 */
+	function extract($text, $start, $end, &$posStart = null, &$posEnd = null ){
+		global $wgContLang;		
+		
+		if( $start != 0)
+			$start = $this->position( $text, $start, 1 );
+		if( $end >= strlen($text) )
+			$end = strlen($text);
+		else
+			$end = $this->position( $text, $end );
+			
+		if(!is_null($posStart))
+			$posStart = $start;
+		if(!is_null($posEnd))
+			$posEnd = $end;
+		
+		if($end > $start)
+			return substr($text, $start, $end-$start);
+		else
+			return '';
+	} 
+	
+	/**
+	 * Find a nonletter near a point (index) in the text
+	 *
+	 * @param $text String
+	 * @param $point Integer
+	 * @param $offset Integer: offset to found index
+	 * @return Integer: nearest nonletter index, or beginning of utf8 char if none
+	 */
+	function position($text, $point, $offset=0 ){
+		$tolerance = 10;
+		$s = max( 0, $point - $tolerance );
+		$l = min( strlen($text), $point + $tolerance ) - $s;
+		$m = array();
+		if( preg_match('/[ ,.!?~!@#$%^&*\(\)+=\-\\\|\[\]"\'<>]/', substr($text,$s,$l), $m, PREG_OFFSET_CAPTURE ) ){
+			return $m[0][1] + $s + $offset;
+		} else{
+			// check if point is on a valid first UTF8 char
+			$char = ord( $text[$point] );
+			while( $char >= 0x80 && $char < 0xc0 ) {
+				// skip trailing bytes
+				$point++;
+				if($point >= strlen($text))
+					return strlen($text);
+				$char = ord( $text[$point] );
+			}
+			return $point;
+			
+		}
+	}
+	
+	/**
+	 * Search extracts for a pattern, and return snippets
+	 *
+	 * @param $pattern String: regexp for matching lines
+	 * @param $extracts Array: extracts to search   
+	 * @param $linesleft Integer: number of extracts to make
+	 * @param $contextchars Integer: length of snippet
+	 * @param $out Array: map for highlighted snippets
+	 * @param $offsets Array: map of starting points of snippets
+	 * @protected
+	 */
+	function process( $pattern, $extracts, &$linesleft, &$contextchars, &$out, &$offsets ){
+		if($linesleft == 0)
+			return; // nothing to do
+		foreach($extracts as $index => $line){			
+			if( array_key_exists($index,$out) )
+				continue; // this line already highlighted
+				
+			$m = array();
+			if ( !preg_match( $pattern, $line, $m, PREG_OFFSET_CAPTURE ) )
+				continue;
+				
+			$offset = $m[0][1];
+			$len = strlen($m[0][0]);
+			if($offset + $len < $contextchars)
+				$begin = 0; 
+			elseif( $len > $contextchars)
+				$begin = $offset;
+			else
+				$begin = $offset + intval( ($len - $contextchars) / 2 );
+			
+			$end = $begin + $contextchars;
+			
+			$posBegin = $begin;
+			// basic snippet from this line
+			$out[$index] = $this->extract($line,$begin,$end,$posBegin);
+			$offsets[$index] = $posBegin;
+			$linesleft--;			
+			if($linesleft == 0)
+				return;
+		}
+	}
+	
+	/** 
+	 * Basic wikitext removal
+	 * @protected
+	 */
+	function removeWiki($text) {
+		$fname = __METHOD__;
+		wfProfileIn( $fname );
+		
+		//$text = preg_replace("/'{2,5}/", "", $text);
+		//$text = preg_replace("/\[[a-z]+:\/\/[^ ]+ ([^]]+)\]/", "\\2", $text);
+		//$text = preg_replace("/\[\[([^]|]+)\]\]/", "\\1", $text);
+		//$text = preg_replace("/\[\[([^]]+\|)?([^|]]+)\]\]/", "\\2", $text);
+		//$text = preg_replace("/\\{\\|(.*?)\\|\\}/", "", $text);
+		//$text = preg_replace("/\\[\\[[A-Za-z_-]+:([^|]+?)\\]\\]/", "", $text);
+		$text = preg_replace("/\\{\\{([^|]+?)\\}\\}/", "", $text);
+		$text = preg_replace("/\\{\\{([^|]+\\|)(.*?)\\}\\}/", "\\2", $text);
+		$text = preg_replace("/\\[\\[([^|]+?)\\]\\]/", "\\1", $text);		
+		$text = preg_replace_callback("/\\[\\[([^|]+\\|)(.*?)\\]\\]/", array($this,'linkReplace'), $text);
+		//$text = preg_replace("/\\[\\[([^|]+\\|)(.*?)\\]\\]/", "\\2", $text);
+		$text = preg_replace("/<\/?[^>]+>/", "", $text);
+		$text = preg_replace("/'''''/", "", $text);
+		$text = preg_replace("/('''|<\/?[iIuUbB]>)/", "", $text);
+		$text = preg_replace("/''/", "", $text);
+		
+		wfProfileOut( $fname );
+		return $text;
+	}
+	
+	/**
+	 * callback to replace [[target|caption]] kind of links, if
+	 * the target is category or image, leave it
+	 *
+	 * @param $matches Array
+	 */
+	function linkReplace($matches){
+		$colon = strpos( $matches[1], ':' ); 
+		if( $colon === false )
+			return $matches[2]; // replace with caption
+		global $wgContLang;
+		$ns = substr( $matches[1], 0, $colon );
+		$index = $wgContLang->getNsIndex($ns);
+		if( $index !== false && ($index == NS_FILE || $index == NS_CATEGORY) )
+			return $matches[0]; // return the whole thing 
+		else
+			return $matches[2];
+		
+	}
+
+	/**
+     * Simple & fast snippet extraction, but gives completely unrelevant
+     * snippets
+     *
+     * @param $text String
+     * @param $terms Array
+     * @param $contextlines Integer
+     * @param $contextchars Integer
+     * @return String
+     */
+    public function highlightSimple( $text, $terms, $contextlines, $contextchars ) {
+        global $wgLang, $wgContLang;
+        $fname = __METHOD__;
+
+        $lines = explode( "\n", $text );
+        
+        $terms = implode( '|', $terms );
+        $max = intval( $contextchars ) + 1;
+        $pat1 = "/(.*)($terms)(.{0,$max})/i";
+
+        $lineno = 0;
+
+        $extract = "";
+        wfProfileIn( "$fname-extract" );
+        foreach ( $lines as $line ) {
+            if ( 0 == $contextlines ) {
+                break;
+            }
+            ++$lineno;
+            $m = array();
+            if ( ! preg_match( $pat1, $line, $m ) ) {
+                continue;
+            }
+            --$contextlines;
+            $pre = $wgContLang->truncate( $m[1], -$contextchars );
+
+            if ( count( $m ) < 3 ) {
+                $post = '';
+            } else {
+                $post = $wgContLang->truncate( $m[3], $contextchars );
+            }
+
+            $found = $m[2];
+
+            $line = htmlspecialchars( $pre . $found . $post );
+            $pat2 = '/(' . $terms . ")/i";
+            $line = preg_replace( $pat2,
+              "<span class='searchmatch'>\\1</span>", $line );
+
+            $extract .= "${line}\n";
+        }
+        wfProfileOut( "$fname-extract" );
+        
+        return $extract;
+    }
+	
+}
+
+/**
+ * Dummy class to be used when non-supported Database engine is present.
+ * @todo Fixme: dummy class should probably try something at least mildly useful,
+ * such as a LIKE search through titles.
+ * @ingroup Search
+ */
+class SearchEngineDummy extends SearchEngine {
+	// no-op
+}
diff --git a/includes/search/SearchIBM_DB2.php b/includes/search/SearchIBM_DB2.php
new file mode 100644
index 00000000..d7587186
--- /dev/null
+++ b/includes/search/SearchIBM_DB2.php
@@ -0,0 +1,224 @@
+<?php
+# Copyright (C) 2004 Brion Vibber <brion@pobox.com>
+# http://www.mediawiki.org/
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+# http://www.gnu.org/copyleft/gpl.html
+
+/**
+ * @file
+ * @ingroup Search
+ */
+
+/**
+ * Search engine hook base class for IBM DB2
+ * @ingroup Search
+ */
+class SearchIBM_DB2 extends SearchEngine {
+	function __construct($db) {
+		$this->db = $db;
+	}
+
+	/**
+	 * Perform a full text search query and return a result set.
+	 *
+	 * @param $term String: raw search term
+	 * @return SqlSearchResultSet
+	 */
+	function searchText( $term ) {
+		$resultSet = $this->db->resultObject($this->db->query($this->getQuery($this->filter($term), true)));
+		return new SqlSearchResultSet($resultSet, $this->searchTerms);
+	}
+
+	/**
+	 * Perform a title-only search query and return a result set.
+	 *
+	 * @param $term String: taw search term
+	 * @return SqlSearchResultSet
+	 */
+	function searchTitle($term) {
+		$resultSet = $this->db->resultObject($this->db->query($this->getQuery($this->filter($term), false)));
+		return new SqlSearchResultSet($resultSet, $this->searchTerms);
+	}
+
+
+	/**
+	 * Return a partial WHERE clause to exclude redirects, if so set
+	 * @return String
+	 */
+	function queryRedirect() {
+		if ($this->showRedirects) {
+			return '';
+		} else {
+			return 'AND page_is_redirect=0';
+		}
+	}
+
+	/**
+	 * Return a partial WHERE clause to limit the search to the given namespaces
+	 * @return String
+	 */
+	function queryNamespaces() {
+		if( is_null($this->namespaces) )
+			return '';
+		$namespaces = implode(',', $this->namespaces);
+		if ($namespaces == '') {
+			$namespaces = '0';
+		}
+		return 'AND page_namespace IN (' . $namespaces . ')';
+	}
+
+	/**
+	 * Return a LIMIT clause to limit results on the query.
+	 * @return String
+	 */
+	function queryLimit($sql) {
+		return $this->db->limitResult($sql, $this->limit, $this->offset);
+	}
+
+	/**
+	 * Does not do anything for generic search engine
+	 * subclasses may define this though
+	 * @return String
+	 */
+	function queryRanking($filteredTerm, $fulltext) {
+		// requires Net Search Extender or equivalent
+		// return ' ORDER BY score(1)';
+		return '';
+	}
+
+	/**
+	 * Construct the full SQL query to do the search.
+	 * The guts shoulds be constructed in queryMain()
+	 * @param string $filteredTerm String
+	 * @param bool $fulltext Boolean
+	 */
+	function getQuery( $filteredTerm, $fulltext ) {
+		return $this->queryLimit($this->queryMain($filteredTerm, $fulltext) . ' ' .
+			$this->queryRedirect() . ' ' .
+			$this->queryNamespaces() . ' ' .
+			$this->queryRanking( $filteredTerm, $fulltext ) . ' ');
+	}
+
+
+	/**
+	 * Picks which field to index on, depending on what type of query.
+	 * @param $fulltext Boolean
+	 * @return String
+	 */
+	function getIndexField($fulltext) {
+		return $fulltext ? 'si_text' : 'si_title';
+	}
+
+	/**
+	 * Get the base part of the search query.
+	 *
+	 * @param string $filteredTerm String
+	 * @param bool $fulltext Boolean
+	 * @return String
+	 */
+	function queryMain( $filteredTerm, $fulltext ) {
+		$match = $this->parseQuery($filteredTerm, $fulltext);
+		$page        = $this->db->tableName('page');
+		$searchindex = $this->db->tableName('searchindex');
+		return 'SELECT page_id, page_namespace, page_title ' .
+			"FROM $page,$searchindex " .
+			'WHERE page_id=si_page AND ' . $match;
+	}
+
+	/** @todo document */
+	function parseQuery($filteredText, $fulltext) {
+		global $wgContLang;
+		$lc = SearchEngine::legalSearchChars();
+		$this->searchTerms = array();
+
+		# FIXME: This doesn't handle parenthetical expressions.
+		$m = array();
+		$q = array();
+
+		if (preg_match_all('/([-+<>~]?)(([' . $lc . ']+)(\*?)|"[^"]*")/',
+			  $filteredText, $m, PREG_SET_ORDER)) {
+			foreach($m as $terms) {
+
+				// Search terms in all variant forms, only
+				// apply on wiki with LanguageConverter
+				$temp_terms = $wgContLang->autoConvertToAllVariants( $terms[2] );
+				if( is_array( $temp_terms )) {
+					$temp_terms = array_unique( array_values( $temp_terms ));
+					foreach( $temp_terms as $t )
+						$q[] = $terms[1] . $wgContLang->normalizeForSearch( $t );
+				}
+				else
+					$q[] = $terms[1] . $wgContLang->normalizeForSearch( $terms[2] );
+
+				if (!empty($terms[3])) {
+					$regexp = preg_quote( $terms[3], '/' );
+					if ($terms[4])
+						$regexp .= "[0-9A-Za-z_]+";
+				} else {
+					$regexp = preg_quote(str_replace('"', '', $terms[2]), '/');
+				}
+				$this->searchTerms[] = $regexp;
+			}
+		}
+
+		$searchon = $this->db->strencode(join(',', $q));
+		$field = $this->getIndexField($fulltext);
+		
+		// requires Net Search Extender or equivalent
+		//return " CONTAINS($field, '$searchon') > 0 ";
+		
+		return " lcase($field) LIKE lcase('%$searchon%')";
+	}
+
+	/**
+	 * Create or update the search index record for the given page.
+	 * Title and text should be pre-processed.
+	 *
+	 * @param $id Integer
+	 * @param $title String
+	 * @param $text String
+	 */
+	function update($id, $title, $text) {
+		$dbw = wfGetDB(DB_MASTER);
+		$dbw->replace('searchindex',
+			array('si_page'),
+			array(
+				'si_page' => $id,
+				'si_title' => $title,
+				'si_text' => $text
+			), 'SearchIBM_DB2::update' );
+		// ?
+		//$dbw->query("CALL ctx_ddl.sync_index('si_text_idx')");
+		//$dbw->query("CALL ctx_ddl.sync_index('si_title_idx')");
+	}
+
+	/**
+	 * Update a search index record's title only.
+	 * Title should be pre-processed.
+	 *
+	 * @param $id Integer
+	 * @param $title String
+	 */
+	function updateTitle($id, $title) {
+		$dbw = wfGetDB(DB_MASTER);
+
+		$dbw->update('searchindex',
+			array('si_title' => $title),
+			array('si_page'  => $id),
+			'SearchIBM_DB2::updateTitle',
+			array());
+	}
+}
diff --git a/includes/search/SearchMySQL.php b/includes/search/SearchMySQL.php
new file mode 100644
index 00000000..0c238be8
--- /dev/null
+++ b/includes/search/SearchMySQL.php
@@ -0,0 +1,412 @@
+<?php
+# Copyright (C) 2004 Brion Vibber <brion@pobox.com>
+# http://www.mediawiki.org/
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+# http://www.gnu.org/copyleft/gpl.html
+
+/**
+ * @file
+ * @ingroup Search
+ */
+
+/**
+ * Search engine hook for MySQL 4+
+ * @ingroup Search
+ */
+class SearchMySQL extends SearchEngine {
+	var $strictMatching = true;
+	static $mMinSearchLength;
+
+	/** @todo document */
+	function __construct( $db ) {
+		$this->db = $db;
+	}
+
+	/** 
+	 * Parse the user's query and transform it into an SQL fragment which will 
+	 * become part of a WHERE clause
+	 */
+	function parseQuery( $filteredText, $fulltext ) {
+		global $wgContLang;
+		$lc = SearchEngine::legalSearchChars(); // Minus format chars
+		$searchon = '';
+		$this->searchTerms = array();
+
+		# FIXME: This doesn't handle parenthetical expressions.
+		$m = array();
+		if( preg_match_all( '/([-+<>~]?)(([' . $lc . ']+)(\*?)|"[^"]*")/',
+			  $filteredText, $m, PREG_SET_ORDER ) ) {
+			foreach( $m as $bits ) {
+				@list( /* all */, $modifier, $term, $nonQuoted, $wildcard ) = $bits;
+				
+				if( $nonQuoted != '' ) {
+					$term = $nonQuoted;
+					$quote = '';
+				} else {
+					$term = str_replace( '"', '', $term );
+					$quote = '"';
+				}
+			
+				if( $searchon !== '' ) $searchon .= ' ';
+				if( $this->strictMatching && ($modifier == '') ) {
+					// If we leave this out, boolean op defaults to OR which is rarely helpful.
+					$modifier = '+';
+				}
+				
+				// Some languages such as Serbian store the input form in the search index,
+				// so we may need to search for matches in multiple writing system variants.
+				$convertedVariants = $wgContLang->autoConvertToAllVariants( $term );
+				if( is_array( $convertedVariants ) ) {
+					$variants = array_unique( array_values( $convertedVariants ) );
+				} else {
+					$variants = array( $term );
+				}
+				
+				// The low-level search index does some processing on input to work
+				// around problems with minimum lengths and encoding in MySQL's
+				// fulltext engine.
+				// For Chinese this also inserts spaces between adjacent Han characters.
+				$strippedVariants = array_map(
+					array( $wgContLang, 'normalizeForSearch' ),
+					$variants );
+				
+				// Some languages such as Chinese force all variants to a canonical
+				// form when stripping to the low-level search index, so to be sure
+				// let's check our variants list for unique items after stripping.
+				$strippedVariants = array_unique( $strippedVariants );
+				
+				$searchon .= $modifier;
+				if( count( $strippedVariants) > 1 )
+					$searchon .= '(';
+				foreach( $strippedVariants as $stripped ) {
+					$stripped = $this->normalizeText( $stripped );
+					if( $nonQuoted && strpos( $stripped, ' ' ) !== false ) {
+						// Hack for Chinese: we need to toss in quotes for
+						// multiple-character phrases since normalizeForSearch()
+						// added spaces between them to make word breaks.
+						$stripped = '"' . trim( $stripped ) . '"';
+					}
+					$searchon .= "$quote$stripped$quote$wildcard ";
+				}
+				if( count( $strippedVariants) > 1 )
+					$searchon .= ')';
+				
+				// Match individual terms or quoted phrase in result highlighting...
+				// Note that variants will be introduced in a later stage for highlighting!
+				$regexp = $this->regexTerm( $term, $wildcard );
+				$this->searchTerms[] = $regexp;
+			}
+			wfDebug( __METHOD__ . ": Would search with '$searchon'\n" );
+			wfDebug( __METHOD__ . ': Match with /' . implode( '|', $this->searchTerms ) . "/\n" );
+		} else {
+			wfDebug( __METHOD__ . ": Can't understand search query '{$filteredText}'\n" );
+		}
+
+		$searchon = $this->db->strencode( $searchon );
+		$field = $this->getIndexField( $fulltext );
+		return " MATCH($field) AGAINST('$searchon' IN BOOLEAN MODE) ";
+	}
+	
+	function regexTerm( $string, $wildcard ) {
+		global $wgContLang;
+		
+		$regex = preg_quote( $string, '/' );
+		if( $wgContLang->hasWordBreaks() ) {
+			if( $wildcard ) {
+				// Don't cut off the final bit!
+				$regex = "\b$regex";
+			} else {
+				$regex = "\b$regex\b";
+			}
+		} else {
+			// For Chinese, words may legitimately abut other words in the text literal.
+			// Don't add \b boundary checks... note this could cause false positives
+			// for latin chars.
+		}
+		return $regex;
+	}
+
+	public static function legalSearchChars() {
+		return "\"*" . parent::legalSearchChars();
+	}
+
+	/**
+	 * Perform a full text search query and return a result set.
+	 *
+	 * @param $term String: raw search term
+	 * @return MySQLSearchResultSet
+	 */
+	function searchText( $term ) {
+		return $this->searchInternal( $term, true );
+	}
+
+	/**
+	 * Perform a title-only search query and return a result set.
+	 *
+	 * @param $term String: raw search term
+	 * @return MySQLSearchResultSet
+	 */
+	function searchTitle( $term ) {
+		return $this->searchInternal( $term, false );
+	}
+	
+	protected function searchInternal( $term, $fulltext ) {
+		global $wgCountTotalSearchHits;
+		
+		$filteredTerm = $this->filter( $term );
+		$resultSet = $this->db->query( $this->getQuery( $filteredTerm, $fulltext ) );
+		
+		$total = null;
+		if( $wgCountTotalSearchHits ) {
+			$totalResult = $this->db->query( $this->getCountQuery( $filteredTerm, $fulltext ) );
+			$row = $totalResult->fetchObject();
+			if( $row ) {
+				$total = intval( $row->c );
+			}
+			$totalResult->free();
+		}
+		
+		return new MySQLSearchResultSet( $resultSet, $this->searchTerms, $total );
+	}
+
+
+	/**
+	 * Return a partial WHERE clause to exclude redirects, if so set
+	 * @return String
+	 */
+	function queryRedirect() {
+		if( $this->showRedirects ) {
+			return '';
+		} else {
+			return 'AND page_is_redirect=0';
+		}
+	}
+
+	/**
+	 * Return a partial WHERE clause to limit the search to the given namespaces
+	 * @return String
+	 */
+	function queryNamespaces() {
+		if( is_null($this->namespaces) )
+			return '';  # search all
+		if ( !count( $this->namespaces ) ) {
+			$namespaces = '0';
+		} else {
+			$namespaces = $this->db->makeList( $this->namespaces );
+		}
+		return 'AND page_namespace IN (' . $namespaces . ')';
+	}
+
+	/**
+	 * Return a LIMIT clause to limit results on the query.
+	 * @return String
+	 */
+	function queryLimit() {
+		return $this->db->limitResult( '', $this->limit, $this->offset );
+	}
+
+	/**
+	 * Does not do anything for generic search engine
+	 * subclasses may define this though
+	 * @return String
+	 */
+	function queryRanking( $filteredTerm, $fulltext ) {
+		return '';
+	}
+
+	/**
+	 * Construct the full SQL query to do the search.
+	 * The guts shoulds be constructed in queryMain()
+	 * @param $filteredTerm String
+	 * @param $fulltext Boolean
+	 */
+	function getQuery( $filteredTerm, $fulltext ) {
+		return $this->queryMain( $filteredTerm, $fulltext ) . ' ' .
+			$this->queryRedirect() . ' ' .
+			$this->queryNamespaces() . ' ' .
+			$this->queryRanking( $filteredTerm, $fulltext ) . ' ' .
+			$this->queryLimit();
+	}
+	
+	/**
+	 * Picks which field to index on, depending on what type of query.
+	 * @param $fulltext Boolean
+	 * @return String
+	 */
+	function getIndexField( $fulltext ) {
+		return $fulltext ? 'si_text' : 'si_title';
+	}
+
+	/**
+	 * Get the base part of the search query.
+	 * The actual match syntax will depend on the server
+	 * version; MySQL 3 and MySQL 4 have different capabilities
+	 * in their fulltext search indexes.
+	 *
+	 * @param $filteredTerm String
+	 * @param $fulltext Boolean
+	 * @return String
+	 */
+	function queryMain( $filteredTerm, $fulltext ) {
+		$match = $this->parseQuery( $filteredTerm, $fulltext );
+		$page        = $this->db->tableName( 'page' );
+		$searchindex = $this->db->tableName( 'searchindex' );
+		return 'SELECT page_id, page_namespace, page_title ' .
+			"FROM $page,$searchindex " .
+			'WHERE page_id=si_page AND ' . $match;
+	}
+
+	function getCountQuery( $filteredTerm, $fulltext ) {
+		$match = $this->parseQuery( $filteredTerm, $fulltext );
+		$page        = $this->db->tableName( 'page' );
+		$searchindex = $this->db->tableName( 'searchindex' );
+		return "SELECT COUNT(*) AS c " .
+			"FROM $page,$searchindex " .
+			'WHERE page_id=si_page AND ' . $match .
+			$this->queryRedirect() . ' ' .
+			$this->queryNamespaces();
+	}
+
+	/**
+	 * Create or update the search index record for the given page.
+	 * Title and text should be pre-processed.
+	 *
+	 * @param $id Integer
+	 * @param $title String
+	 * @param $text String
+	 */
+	function update( $id, $title, $text ) {
+		$dbw = wfGetDB( DB_MASTER );
+		$dbw->replace( 'searchindex',
+			array( 'si_page' ),
+			array(
+				'si_page' => $id,
+				'si_title' => $this->normalizeText( $title ),
+				'si_text' => $this->normalizeText( $text )
+			), __METHOD__ );
+	}
+
+	/**
+	 * Update a search index record's title only.
+	 * Title should be pre-processed.
+	 *
+	 * @param $id Integer
+	 * @param $title String
+	 */
+    function updateTitle( $id, $title ) {
+		$dbw = wfGetDB( DB_MASTER );
+
+		$dbw->update( 'searchindex',
+			array( 'si_title' => $this->normalizeText( $title ) ),
+			array( 'si_page'  => $id ),
+			__METHOD__,
+			array( $dbw->lowPriorityOption() ) );
+	}
+
+	/**
+	 * Converts some characters for MySQL's indexing to grok it correctly,
+	 * and pads short words to overcome limitations.
+	 */
+	function normalizeText( $string ) {
+		global $wgContLang;
+
+		wfProfileIn( __METHOD__ );
+		
+		// Some languages such as Chinese require word segmentation
+		$out = $wgContLang->wordSegmentation( $string );
+
+		// MySQL fulltext index doesn't grok utf-8, so we
+		// need to fold cases and convert to hex
+		$out = preg_replace_callback(
+			"/([\\xc0-\\xff][\\x80-\\xbf]*)/",
+			array( $this, 'stripForSearchCallback' ),
+			$wgContLang->lc( $out ) );
+
+		// And to add insult to injury, the default indexing
+		// ignores short words... Pad them so we can pass them
+		// through without reconfiguring the server...
+		$minLength = $this->minSearchLength();
+		if( $minLength > 1 ) {
+			$n = $minLength - 1;
+			$out = preg_replace(
+				"/\b(\w{1,$n})\b/",
+				"$1u800",
+				$out );
+		}
+
+		// Periods within things like hostnames and IP addresses
+		// are also important -- we want a search for "example.com"
+		// or "192.168.1.1" to work sanely.
+		//
+		// MySQL's search seems to ignore them, so you'd match on
+		// "example.wikipedia.com" and "192.168.83.1" as well.
+		$out = preg_replace(
+			"/(\w)\.(\w|\*)/u",
+			"$1u82e$2",
+			$out );
+
+		wfProfileOut( __METHOD__ );
+		
+		return $out;
+	}
+
+	/**
+	 * Armor a case-folded UTF-8 string to get through MySQL's
+	 * fulltext search without being mucked up by funny charset
+	 * settings or anything else of the sort.
+	 */
+	protected function stripForSearchCallback( $matches ) {
+		return 'u8' . bin2hex( $matches[1] );
+	}
+
+	/**
+	 * Check MySQL server's ft_min_word_len setting so we know
+	 * if we need to pad short words...
+	 * 
+	 * @return int
+	 */
+	protected function minSearchLength() {
+		if( is_null( self::$mMinSearchLength ) ) {
+			$sql = "SHOW GLOBAL VARIABLES LIKE 'ft\\_min\\_word\\_len'";
+
+			$dbr = wfGetDB( DB_SLAVE );
+			$result = $dbr->query( $sql );
+			$row = $result->fetchObject();
+			$result->free();
+
+			if( $row && $row->Variable_name == 'ft_min_word_len' ) {
+				self::$mMinSearchLength = intval( $row->Value );
+			} else {
+				self::$mMinSearchLength = 0;
+			}
+		}
+		return self::$mMinSearchLength;
+	}
+}
+
+/**
+ * @ingroup Search
+ */
+class MySQLSearchResultSet extends SqlSearchResultSet {
+	function MySQLSearchResultSet( $resultSet, $terms, $totalHits=null ) {
+		parent::__construct( $resultSet, $terms );
+		$this->mTotalHits = $totalHits;
+	}
+
+	function getTotalHits() {
+		return $this->mTotalHits;
+	}
+}
\ No newline at end of file
diff --git a/includes/search/SearchMySQL4.php b/includes/search/SearchMySQL4.php
new file mode 100644
index 00000000..3e2bb2d1
--- /dev/null
+++ b/includes/search/SearchMySQL4.php
@@ -0,0 +1,34 @@
+<?php
+# Copyright (C) 2004 Brion Vibber <brion@pobox.com>
+# http://www.mediawiki.org/
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+# http://www.gnu.org/copyleft/gpl.html
+
+/**
+ * @file
+ * @ingroup Search
+ */
+
+/**
+ * Search engine hook for MySQL 4+
+ * This class retained for backwards compatibility...
+ * The meat's been moved to SearchMySQL, since the 3.x variety is gone.
+ * @ingroup Search
+ * @deprecated
+ */
+class SearchMySQL4 extends SearchMySQL {
+	/* whee */
+}
diff --git a/includes/search/SearchOracle.php b/includes/search/SearchOracle.php
new file mode 100644
index 00000000..e4c5deee
--- /dev/null
+++ b/includes/search/SearchOracle.php
@@ -0,0 +1,268 @@
+<?php
+# Copyright (C) 2004 Brion Vibber <brion@pobox.com>
+# http://www.mediawiki.org/
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+# http://www.gnu.org/copyleft/gpl.html
+
+/**
+ * @file
+ * @ingroup Search
+ */
+
+/**
+ * Search engine hook base class for Oracle (ConText).
+ * @ingroup Search
+ */
+class SearchOracle extends SearchEngine {
+	
+	private $reservedWords = array ('ABOUT' => 1, 
+									'ACCUM' => 1, 
+									'AND' => 1, 
+									'BT' => 1, 
+									'BTG' => 1, 
+									'BTI' => 1, 
+									'BTP' => 1,
+									'FUZZY' => 1, 
+									'HASPATH' => 1, 
+									'INPATH' => 1, 
+									'MINUS' => 1, 
+									'NEAR' => 1, 
+									'NOT' => 1,
+									'NT' => 1, 
+									'NTG' => 1, 
+									'NTI' => 1, 
+									'NTP' => 1, 
+									'OR' => 1, 
+									'PT' => 1, 
+									'RT' => 1, 
+									'SQE' => 1,
+									'SYN' => 1, 
+									'TR' => 1, 
+									'TRSYN' => 1, 
+									'TT' => 1, 
+									'WITHIN' => 1);
+	
+	function __construct($db) {
+		$this->db = $db;
+	}
+
+	/**
+	 * Perform a full text search query and return a result set.
+	 *
+	 * @param $term String: raw search term
+	 * @return SqlSearchResultSet
+	 */
+	function searchText( $term ) {
+		if ($term == '')
+			return new SqlSearchResultSet(false, '');
+
+		$resultSet = $this->db->resultObject($this->db->query($this->getQuery($this->filter($term), true)));
+		return new SqlSearchResultSet($resultSet, $this->searchTerms);
+	}
+
+	/**
+	 * Perform a title-only search query and return a result set.
+	 *
+	 * @param $term String: raw search term
+	 * @return SqlSearchResultSet
+	 */
+	function searchTitle($term) {
+		if ($term == '')
+			return new SqlSearchResultSet(false, '');
+
+		$resultSet = $this->db->resultObject($this->db->query($this->getQuery($this->filter($term), false)));
+		return new MySQLSearchResultSet($resultSet, $this->searchTerms);
+	}
+
+
+	/**
+	 * Return a partial WHERE clause to exclude redirects, if so set
+	 * @return String
+	 */
+	function queryRedirect() {
+		if ($this->showRedirects) {
+			return '';
+		} else {
+			return 'AND page_is_redirect=0';
+		}
+	}
+
+	/**
+	 * Return a partial WHERE clause to limit the search to the given namespaces
+	 * @return String
+	 */
+	function queryNamespaces() {
+		if( is_null($this->namespaces) )
+			return '';
+		if ( !count( $this->namespaces ) ) {
+			$namespaces = '0';
+		} else {
+			$namespaces = $this->db->makeList( $this->namespaces );
+		}
+		return 'AND page_namespace IN (' . $namespaces . ')';
+	}
+
+	/**
+	 * Return a LIMIT clause to limit results on the query.
+	 * @return String
+	 */
+	function queryLimit($sql) {
+		return $this->db->limitResult($sql, $this->limit, $this->offset);
+	}
+
+	/**
+	 * Does not do anything for generic search engine
+	 * subclasses may define this though
+	 * @return String
+	 */
+	function queryRanking($filteredTerm, $fulltext) {
+		return ' ORDER BY score(1)';
+	}
+
+	/**
+	 * Construct the full SQL query to do the search.
+	 * The guts shoulds be constructed in queryMain()
+	 * @param $filteredTerm String
+	 * @param $fulltext Boolean
+	 */
+	function getQuery( $filteredTerm, $fulltext ) {
+		return $this->queryLimit($this->queryMain($filteredTerm, $fulltext) . ' ' .
+			$this->queryRedirect() . ' ' .
+			$this->queryNamespaces() . ' ' .
+			$this->queryRanking( $filteredTerm, $fulltext ) . ' ');
+	}
+
+
+	/**
+	 * Picks which field to index on, depending on what type of query.
+	 * @param $fulltext Boolean
+	 * @return String
+	 */
+	function getIndexField($fulltext) {
+		return $fulltext ? 'si_text' : 'si_title';
+	}
+
+	/**
+	 * Get the base part of the search query.
+	 *
+	 * @param $filteredTerm String
+	 * @param $fulltext Boolean
+	 * @return String
+	 */
+	function queryMain( $filteredTerm, $fulltext ) {
+		$match = $this->parseQuery($filteredTerm, $fulltext);
+		$page        = $this->db->tableName('page');
+		$searchindex = $this->db->tableName('searchindex');
+		return 'SELECT page_id, page_namespace, page_title ' .
+			"FROM $page,$searchindex " .
+			'WHERE page_id=si_page AND ' . $match;
+	}
+
+	/**
+	 * Parse a user input search string, and return an SQL fragment to be used
+	 * as part of a WHERE clause
+	 */
+	function parseQuery($filteredText, $fulltext) {
+		global $wgContLang;
+		$lc = SearchEngine::legalSearchChars();
+		$this->searchTerms = array();
+
+		# FIXME: This doesn't handle parenthetical expressions.
+		$m = array();
+		$searchon = '';
+		if (preg_match_all('/([-+<>~]?)(([' . $lc . ']+)(\*?)|"[^"]*")/',
+			  $filteredText, $m, PREG_SET_ORDER)) {
+			foreach($m as $terms) {
+				// Search terms in all variant forms, only
+				// apply on wiki with LanguageConverter
+				$temp_terms = $wgContLang->autoConvertToAllVariants( $terms[2] );
+				if( is_array( $temp_terms )) {
+					$temp_terms = array_unique( array_values( $temp_terms ));
+					foreach( $temp_terms as $t ) {
+						$searchon .= ($terms[1] == '-' ? ' ~' : ' & ') . $this->escapeTerm( $t );
+					}
+				}
+				else {
+					$searchon .= ($terms[1] == '-' ? ' ~' : ' & ') . $this->escapeTerm( $terms[2] );
+				}
+				if (!empty($terms[3])) {
+					$regexp = preg_quote( $terms[3], '/' );
+					if ($terms[4])
+						$regexp .= "[0-9A-Za-z_]+";
+				} else {
+					$regexp = preg_quote(str_replace('"', '', $terms[2]), '/');
+				}
+				$this->searchTerms[] = $regexp;
+			}
+		}
+
+
+		$searchon = $this->db->addQuotes(ltrim($searchon, ' &'));
+		$field = $this->getIndexField($fulltext);
+		return " CONTAINS($field, $searchon, 1) > 0 ";
+	}
+
+	private function escapeTerm($t) {
+		global $wgContLang;
+		$t = $wgContLang->normalizeForSearch($t);
+		$t = isset($this->reservedWords[strtoupper($t)]) ? '{'.$t.'}' : $t;
+		$t = preg_replace('/^"(.*)"$/', '($1)', $t);
+		$t = preg_replace('/([-&|])/', '\\\\$1', $t);
+		return $t;
+	}
+	/**
+	 * Create or update the search index record for the given page.
+	 * Title and text should be pre-processed.
+	 *
+	 * @param $id Integer
+	 * @param $title String
+	 * @param $text String
+	 */
+	function update($id, $title, $text) {
+		$dbw = wfGetDB(DB_MASTER);
+		$dbw->replace('searchindex',
+			array('si_page'),
+			array(
+				'si_page' => $id,
+				'si_title' => $title,
+				'si_text' => $text
+			), 'SearchOracle::update' );
+		$dbw->query("CALL ctx_ddl.sync_index('si_text_idx')");
+		$dbw->query("CALL ctx_ddl.sync_index('si_title_idx')");
+	}
+
+	/**
+	 * Update a search index record's title only.
+	 * Title should be pre-processed.
+	 *
+	 * @param int $id
+	 * @param string $title
+	 */
+	function updateTitle($id, $title) {
+		$dbw = wfGetDB(DB_MASTER);
+
+		$dbw->update('searchindex',
+			array('si_title' => $title),
+			array('si_page'  => $id),
+			'SearchOracle::updateTitle',
+			array());
+	}
+
+
+	public static function legalSearchChars() {
+		return "\"" . parent::legalSearchChars();
+	}
+}
diff --git a/includes/search/SearchPostgres.php b/includes/search/SearchPostgres.php
new file mode 100644
index 00000000..0006fa82
--- /dev/null
+++ b/includes/search/SearchPostgres.php
@@ -0,0 +1,246 @@
+<?php
+# Copyright (C) 2006-2007 Greg Sabino Mullane <greg@turnstep.com>
+# http://www.mediawiki.org/
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+# http://www.gnu.org/copyleft/gpl.html
+
+/**
+ * @file
+ * @ingroup Search
+ */
+
+/**
+ * Search engine hook base class for Postgres
+ * @ingroup Search
+ */
+class SearchPostgres extends SearchEngine {
+
+	function __construct( $db ) {
+		$this->db = $db;
+	}
+
+	/**
+	 * Perform a full text search query via tsearch2 and return a result set.
+	 * Currently searches a page's current title (page.page_title) and
+	 * latest revision article text (pagecontent.old_text)
+	 *
+	 * @param $term String: raw search term
+	 * @return PostgresSearchResultSet
+	 */
+	function searchTitle( $term ) {
+		$q = $this->searchQuery( $term , 'titlevector', 'page_title' );
+		$olderror = error_reporting(E_ERROR);
+		$resultSet = $this->db->resultObject( $this->db->query( $q, 'SearchPostgres', true ) );
+		error_reporting($olderror);
+		if (!$resultSet) {
+			// Needed for "Query requires full scan, GIN doesn't support it"
+			return new SearchResultTooMany();
+		}
+		return new PostgresSearchResultSet( $resultSet, $this->searchTerms );
+	}
+	function searchText( $term ) {
+		$q = $this->searchQuery( $term, 'textvector', 'old_text' );
+		$olderror = error_reporting(E_ERROR);
+		$resultSet = $this->db->resultObject( $this->db->query( $q, 'SearchPostgres', true ) );
+		error_reporting($olderror);
+		if (!$resultSet) {
+			return new SearchResultTooMany();
+		}
+		return new PostgresSearchResultSet( $resultSet, $this->searchTerms );
+	}
+
+
+	/*
+	 * Transform the user's search string into a better form for tsearch2
+	 * Returns an SQL fragment consisting of quoted text to search for.
+	*/
+	function parseQuery( $term ) {
+
+		wfDebug( "parseQuery received: $term \n" );
+
+		## No backslashes allowed
+		$term = preg_replace('/\\\/', '', $term);
+
+		## Collapse parens into nearby words:
+		$term = preg_replace('/\s*\(\s*/', ' (', $term);
+		$term = preg_replace('/\s*\)\s*/', ') ', $term);
+
+		## Treat colons as word separators:
+		$term = preg_replace('/:/', ' ', $term);
+
+		$searchstring = '';
+		$m = array();
+		if( preg_match_all('/([-!]?)(\S+)\s*/', $term, $m, PREG_SET_ORDER ) ) {
+			foreach( $m as $terms ) {
+				if (strlen($terms[1])) {
+					$searchstring .= ' & !';
+				}
+				if (strtolower($terms[2]) === 'and') {
+					$searchstring .= ' & ';
+				}
+				else if (strtolower($terms[2]) === 'or' or $terms[2] === '|') {
+					$searchstring .= ' | ';
+				}
+				else if (strtolower($terms[2]) === 'not') {
+					$searchstring .= ' & !';
+				}
+				else {
+					$searchstring .= " & $terms[2]";
+				}
+			}
+		}
+
+		## Strip out leading junk
+		$searchstring = preg_replace('/^[\s\&\|]+/', '', $searchstring);
+
+		## Remove any doubled-up operators
+		$searchstring = preg_replace('/([\!\&\|]) +(?:[\&\|] +)+/', "$1 ", $searchstring);
+
+		## Remove any non-spaced operators (e.g. "Zounds!")
+		$searchstring = preg_replace('/([^ ])[\!\&\|]/', "$1", $searchstring);
+
+		## Remove any trailing whitespace or operators
+		$searchstring = preg_replace('/[\s\!\&\|]+$/', '', $searchstring);
+
+		## Remove unnecessary quotes around everything
+		$searchstring = preg_replace('/^[\'"](.*)[\'"]$/', "$1", $searchstring);
+
+		## Quote the whole thing
+		$searchstring = $this->db->addQuotes($searchstring);
+
+		wfDebug( "parseQuery returned: $searchstring \n" );
+
+		return $searchstring;
+
+	}
+
+	/**
+	 * Construct the full SQL query to do the search.
+	 * @param $filteredTerm String
+	 * @param $fulltext String
+	 */
+	function searchQuery( $term, $fulltext, $colname ) {
+		global $wgDBversion;
+
+		if ( !isset( $wgDBversion ) ) {
+			$this->db->getServerVersion();
+			$wgDBversion = $this->db->numeric_version;
+		}
+		$prefix = $wgDBversion < 8.3 ? "'default'," : '';
+
+		# Get the SQL fragment for the given term
+		$searchstring = $this->parseQuery( $term );
+
+		## We need a separate query here so gin does not complain about empty searches
+		$SQL = "SELECT to_tsquery($prefix $searchstring)";
+		$res = $this->db->doQuery($SQL);
+		if (!$res) {
+			## TODO: Better output (example to catch: one 'two)
+			die ("Sorry, that was not a valid search string. Please go back and try again");
+		}
+		$top = pg_fetch_result($res,0,0);
+
+		if ($top === "") { ## e.g. if only stopwords are used XXX return something better
+			$query = "SELECT page_id, page_namespace, page_title, 0 AS score ".
+				"FROM page p, revision r, pagecontent c WHERE p.page_latest = r.rev_id " .
+				"AND r.rev_text_id = c.old_id AND 1=0";
+		}
+		else {
+			$m = array();
+			if( preg_match_all("/'([^']+)'/", $top, $m, PREG_SET_ORDER ) ) {
+				foreach( $m as $terms ) {
+					$this->searchTerms[$terms[1]] = $terms[1];
+				}
+			}
+
+			$rankscore = $wgDBversion > 8.2 ? 5 : 1;
+			$rank = $wgDBversion < 8.3 ? 'rank' : 'ts_rank';
+			$query = "SELECT page_id, page_namespace, page_title, ".
+			"$rank($fulltext, to_tsquery($prefix $searchstring), $rankscore) AS score ".
+			"FROM page p, revision r, pagecontent c WHERE p.page_latest = r.rev_id " .
+			"AND r.rev_text_id = c.old_id AND $fulltext @@ to_tsquery($prefix $searchstring)";
+		}
+
+		## Redirects
+		if (! $this->showRedirects)
+			$query .= ' AND page_is_redirect = 0';
+
+		## Namespaces - defaults to 0
+		if( !is_null($this->namespaces) ){ // null -> search all
+			if ( count($this->namespaces) < 1)
+				$query .= ' AND page_namespace = 0';
+			else {
+				$namespaces = $this->db->makeList( $this->namespaces );
+				$query .= " AND page_namespace IN ($namespaces)";
+			}
+		}
+
+		$query .= " ORDER BY score DESC, page_id DESC";
+
+		$query .= $this->db->limitResult( '', $this->limit, $this->offset );
+
+		wfDebug( "searchQuery returned: $query \n" );
+
+		return $query;
+	}
+
+	## Most of the work of these two functions are done automatically via triggers
+
+	function update( $pageid, $title, $text ) {
+		## We don't want to index older revisions
+		$SQL = "UPDATE pagecontent SET textvector = NULL WHERE old_id IN ".
+				"(SELECT rev_text_id FROM revision WHERE rev_page = " . intval( $pageid ) . 
+				" ORDER BY rev_text_id DESC OFFSET 1)";
+		$this->db->doQuery($SQL);
+		return true;
+	}
+
+	function updateTitle( $id, $title ) {
+		return true;
+	}
+
+} ## end of the SearchPostgres class
+
+/**
+ * @ingroup Search
+ */
+class PostgresSearchResult extends SearchResult {
+	function __construct( $row ) {
+		parent::__construct($row);
+		$this->score = $row->score;
+	}
+	function getScore() {
+		return $this->score;
+	}
+}
+
+/**
+ * @ingroup Search
+ */
+class PostgresSearchResultSet extends SqlSearchResultSet {
+	function __construct( $resultSet, $terms ) {
+		parent::__construct( $resultSet, $terms );
+	}
+
+	function next() {
+		$row = $this->mResultSet->fetchObject();
+		if( $row === false ) {
+			return false;
+		} else {
+			return new PostgresSearchResult( $row );
+		}
+	}
+}
diff --git a/includes/search/SearchSqlite.php b/includes/search/SearchSqlite.php
new file mode 100644
index 00000000..fb55efec
--- /dev/null
+++ b/includes/search/SearchSqlite.php
@@ -0,0 +1,344 @@
+<?php
+# SQLite search backend, based upon SearchMysql
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+# http://www.gnu.org/copyleft/gpl.html
+
+/**
+ * @file
+ * @ingroup Search
+ */
+
+/**
+ * Search engine hook for SQLite
+ * @ingroup Search
+ */
+class SearchSqlite extends SearchEngine {
+	// Cached because SearchUpdate keeps recreating our class
+	private static $fulltextSupported = null;
+
+	/**
+	 * Creates an instance of this class
+	 * @param $db DatabaseSqlite: database object
+	 */
+	function __construct( $db ) {
+		$this->db = $db;
+	}
+
+	/**
+	 * Whether fulltext search is supported by current schema
+	 * @return Boolean
+	 */
+	function fulltextSearchSupported() {
+		if ( self::$fulltextSupported === null ) {
+			self::$fulltextSupported = $this->db->selectField( 
+				'updatelog', 
+				'ul_key', 
+				array( 'ul_key' => 'fts3' ), 
+				__METHOD__ ) !== false;
+		}
+		return self::$fulltextSupported;
+	}
+
+	/** 
+	 * Parse the user's query and transform it into an SQL fragment which will 
+	 * become part of a WHERE clause
+	 */
+	function parseQuery( $filteredText, $fulltext ) {
+		global $wgContLang;
+		$lc = SearchEngine::legalSearchChars(); // Minus format chars
+		$searchon = '';
+		$this->searchTerms = array();
+
+		$m = array();
+		if( preg_match_all( '/([-+<>~]?)(([' . $lc . ']+)(\*?)|"[^"]*")/',
+			  $filteredText, $m, PREG_SET_ORDER ) ) {
+			foreach( $m as $bits ) {
+				@list( /* all */, $modifier, $term, $nonQuoted, $wildcard ) = $bits;
+				
+				if( $nonQuoted != '' ) {
+					$term = $nonQuoted;
+					$quote = '';
+				} else {
+					$term = str_replace( '"', '', $term );
+					$quote = '"';
+				}
+
+				if( $searchon !== '' ) $searchon .= ' ';
+
+				// Some languages such as Serbian store the input form in the search index,
+				// so we may need to search for matches in multiple writing system variants.
+				$convertedVariants = $wgContLang->autoConvertToAllVariants( $term );
+				if( is_array( $convertedVariants ) ) {
+					$variants = array_unique( array_values( $convertedVariants ) );
+				} else {
+					$variants = array( $term );
+				}
+				
+				// The low-level search index does some processing on input to work
+				// around problems with minimum lengths and encoding in MySQL's
+				// fulltext engine.
+				// For Chinese this also inserts spaces between adjacent Han characters.
+				$strippedVariants = array_map(
+					array( $wgContLang, 'normalizeForSearch' ),
+					$variants );
+				
+				// Some languages such as Chinese force all variants to a canonical
+				// form when stripping to the low-level search index, so to be sure
+				// let's check our variants list for unique items after stripping.
+				$strippedVariants = array_unique( $strippedVariants );
+				
+				$searchon .= $modifier;
+				if( count( $strippedVariants) > 1 )
+					$searchon .= '(';
+				foreach( $strippedVariants as $stripped ) {
+					if( $nonQuoted && strpos( $stripped, ' ' ) !== false ) {
+						// Hack for Chinese: we need to toss in quotes for
+						// multiple-character phrases since normalizeForSearch()
+						// added spaces between them to make word breaks.
+						$stripped = '"' . trim( $stripped ) . '"';
+					}
+					$searchon .= "$quote$stripped$quote$wildcard ";
+				}
+				if( count( $strippedVariants) > 1 )
+					$searchon .= ')';
+				
+				// Match individual terms or quoted phrase in result highlighting...
+				// Note that variants will be introduced in a later stage for highlighting!
+				$regexp = $this->regexTerm( $term, $wildcard );
+				$this->searchTerms[] = $regexp;
+			}
+
+		} else {
+			wfDebug( __METHOD__ . ": Can't understand search query '{$filteredText}'\n" );
+		}
+
+		$searchon = $this->db->strencode( $searchon );
+		$field = $this->getIndexField( $fulltext );
+		return " $field MATCH '$searchon' ";
+	}
+	
+	function regexTerm( $string, $wildcard ) {
+		global $wgContLang;
+		
+		$regex = preg_quote( $string, '/' );
+		if( $wgContLang->hasWordBreaks() ) {
+			if( $wildcard ) {
+				// Don't cut off the final bit!
+				$regex = "\b$regex";
+			} else {
+				$regex = "\b$regex\b";
+			}
+		} else {
+			// For Chinese, words may legitimately abut other words in the text literal.
+			// Don't add \b boundary checks... note this could cause false positives
+			// for latin chars.
+		}
+		return $regex;
+	}
+
+	public static function legalSearchChars() {
+		return "\"*" . parent::legalSearchChars();
+	}
+
+	/**
+	 * Perform a full text search query and return a result set.
+	 *
+	 * @param $term String: raw search term
+	 * @return SqliteSearchResultSet
+	 */
+	function searchText( $term ) {
+		return $this->searchInternal( $term, true );
+	}
+
+	/**
+	 * Perform a title-only search query and return a result set.
+	 *
+	 * @param $term String: raw search term
+	 * @return SqliteSearchResultSet
+	 */
+	function searchTitle( $term ) {
+		return $this->searchInternal( $term, false );
+	}
+	
+	protected function searchInternal( $term, $fulltext ) {
+		global $wgCountTotalSearchHits, $wgContLang;
+
+		if ( !$this->fulltextSearchSupported() ) {
+			return null;
+		}
+
+		$filteredTerm = $this->filter( $wgContLang->lc( $term ) );
+		$resultSet = $this->db->query( $this->getQuery( $filteredTerm, $fulltext ) );
+		
+		$total = null;
+		if( $wgCountTotalSearchHits ) {
+			$totalResult = $this->db->query( $this->getCountQuery( $filteredTerm, $fulltext ) );
+			$row = $totalResult->fetchObject();
+			if( $row ) {
+				$total = intval( $row->c );
+			}
+			$totalResult->free();
+		}
+		
+		return new SqliteSearchResultSet( $resultSet, $this->searchTerms, $total );
+	}
+
+
+	/**
+	 * Return a partial WHERE clause to exclude redirects, if so set
+	 * @return String
+	 */
+	function queryRedirect() {
+		if( $this->showRedirects ) {
+			return '';
+		} else {
+			return 'AND page_is_redirect=0';
+		}
+	}
+
+	/**
+	 * Return a partial WHERE clause to limit the search to the given namespaces
+	 * @return String
+	 */
+	function queryNamespaces() {
+		if( is_null($this->namespaces) )
+			return '';  # search all
+		if ( !count( $this->namespaces ) ) {
+			$namespaces = '0';
+		} else {
+			$namespaces = $this->db->makeList( $this->namespaces );
+		}
+		return 'AND page_namespace IN (' . $namespaces . ')';
+	}
+
+	/**
+	 * Returns a query with limit for number of results set.
+	 * @param $sql String: 
+	 * @return String
+	 */
+	function limitResult( $sql ) {
+		return $this->db->limitResult( $sql, $this->limit, $this->offset );
+	}
+
+	/**
+	 * Construct the full SQL query to do the search.
+	 * The guts shoulds be constructed in queryMain()
+	 * @param $filteredTerm String
+	 * @param $fulltext Boolean
+	 */
+	function getQuery( $filteredTerm, $fulltext ) {
+		return $this->limitResult(
+			$this->queryMain( $filteredTerm, $fulltext ) . ' ' .
+			$this->queryRedirect() . ' ' .
+			$this->queryNamespaces()
+		);
+	}
+	
+	/**
+	 * Picks which field to index on, depending on what type of query.
+	 * @param $fulltext Boolean
+	 * @return String
+	 */
+	function getIndexField( $fulltext ) {
+		return $fulltext ? 'si_text' : 'si_title';
+	}
+
+	/**
+	 * Get the base part of the search query.
+	 *
+	 * @param $filteredTerm String
+	 * @param $fulltext Boolean
+	 * @return String
+	 */
+	function queryMain( $filteredTerm, $fulltext ) {
+		$match = $this->parseQuery( $filteredTerm, $fulltext );
+		$page        = $this->db->tableName( 'page' );
+		$searchindex = $this->db->tableName( 'searchindex' );
+		return "SELECT $searchindex.rowid, page_namespace, page_title " .
+			"FROM $page,$searchindex " .
+			"WHERE page_id=$searchindex.rowid AND $match";
+	}
+
+	function getCountQuery( $filteredTerm, $fulltext ) {
+		$match = $this->parseQuery( $filteredTerm, $fulltext );
+		$page        = $this->db->tableName( 'page' );
+		$searchindex = $this->db->tableName( 'searchindex' );
+		return "SELECT COUNT(*) AS c " .
+			"FROM $page,$searchindex " .
+			"WHERE page_id=$searchindex.rowid AND $match" .
+			$this->queryRedirect() . ' ' .
+			$this->queryNamespaces();
+	}
+
+	/**
+	 * Create or update the search index record for the given page.
+	 * Title and text should be pre-processed.
+	 *
+	 * @param $id Integer
+	 * @param $title String
+	 * @param $text String
+	 */
+	function update( $id, $title, $text ) {
+		if ( !$this->fulltextSearchSupported() ) {
+			return;
+		}
+		// @todo: find a method to do it in a single request,
+		// couldn't do it so far due to typelessness of FTS3 tables.
+		$dbw = wfGetDB( DB_MASTER );
+
+		$dbw->delete( 'searchindex', array( 'rowid' => $id ), __METHOD__ );
+		
+		$dbw->insert( 'searchindex',
+			array(
+				'rowid' => $id,
+				'si_title' => $title,
+				'si_text' => $text
+			), __METHOD__ );
+	}
+
+	/**
+	 * Update a search index record's title only.
+	 * Title should be pre-processed.
+	 *
+	 * @param $id Integer
+	 * @param $title String
+	 */
+    function updateTitle( $id, $title ) {
+		if ( !$this->fulltextSearchSupported() ) {
+			return;
+		}
+		$dbw = wfGetDB( DB_MASTER );
+
+		$dbw->update( 'searchindex',
+			array( 'si_title' => $title ),
+			array( 'rowid'  => $id ),
+			__METHOD__ );
+	}
+}
+
+/**
+ * @ingroup Search
+ */
+class SqliteSearchResultSet extends SqlSearchResultSet {
+	function SqliteSearchResultSet( $resultSet, $terms, $totalHits=null ) {
+		parent::__construct( $resultSet, $terms );
+		$this->mTotalHits = $totalHits;
+	}
+
+	function getTotalHits() {
+		return $this->mTotalHits;
+	}
+}
\ No newline at end of file
diff --git a/includes/search/SearchUpdate.php b/includes/search/SearchUpdate.php
new file mode 100644
index 00000000..e30c70e6
--- /dev/null
+++ b/includes/search/SearchUpdate.php
@@ -0,0 +1,113 @@
+<?php
+/**
+ * See deferred.txt
+ * @ingroup Search
+ */
+class SearchUpdate {
+
+	/* private */ var $mId = 0, $mNamespace, $mTitle, $mText;
+	/* private */ var $mTitleWords;
+
+	function SearchUpdate( $id, $title, $text = false ) {
+		$nt = Title::newFromText( $title );
+		if( $nt ) {
+			$this->mId = $id;
+			$this->mText = $text;
+
+			$this->mNamespace = $nt->getNamespace();
+			$this->mTitle = $nt->getText(); # Discard namespace
+
+			$this->mTitleWords = $this->mTextWords = array();
+		} else {
+			wfDebug( "SearchUpdate object created with invalid title '$title'\n" );
+		}
+	}
+
+	function doUpdate() {
+		global $wgContLang, $wgDisableSearchUpdate;
+
+		if( $wgDisableSearchUpdate || !$this->mId ) {
+			return false;
+		}
+		$fname = 'SearchUpdate::doUpdate';
+		wfProfileIn( $fname );
+
+		$search = SearchEngine::create();
+		$lc = SearchEngine::legalSearchChars() . '&#;';
+
+		if( $this->mText === false ) {
+			$search->updateTitle($this->mId,
+				Title::indexTitle( $this->mNamespace, $this->mTitle ));
+			wfProfileOut( $fname );
+			return;
+		}
+
+		# Language-specific strip/conversion
+		$text = $wgContLang->normalizeForSearch( $this->mText );
+
+		wfProfileIn( $fname.'-regexps' );
+		$text = preg_replace( "/<\\/?\\s*[A-Za-z][^>]*?>/",
+			' ', $wgContLang->lc( " " . $text . " " ) ); # Strip HTML markup
+		$text = preg_replace( "/(^|\\n)==\\s*([^\\n]+)\\s*==(\\s)/sD",
+		  "\\1\\2 \\2 \\2\\3", $text ); # Emphasize headings
+
+		# Strip external URLs
+		$uc = "A-Za-z0-9_\\/:.,~%\\-+&;#?!=()@\\xA0-\\xFF";
+		$protos = "http|https|ftp|mailto|news|gopher";
+		$pat = "/(^|[^\\[])({$protos}):[{$uc}]+([^{$uc}]|$)/";
+		$text = preg_replace( $pat, "\\1 \\3", $text );
+
+		$p1 = "/([^\\[])\\[({$protos}):[{$uc}]+]/";
+		$p2 = "/([^\\[])\\[({$protos}):[{$uc}]+\\s+([^\\]]+)]/";
+		$text = preg_replace( $p1, "\\1 ", $text );
+		$text = preg_replace( $p2, "\\1 \\3 ", $text );
+
+		# Internal image links
+		$pat2 = "/\\[\\[image:([{$uc}]+)\\.(gif|png|jpg|jpeg)([^{$uc}])/i";
+		$text = preg_replace( $pat2, " \\1 \\3", $text );
+
+		$text = preg_replace( "/([^{$lc}])([{$lc}]+)]]([a-z]+)/",
+		  "\\1\\2 \\2\\3", $text ); # Handle [[game]]s
+
+		# Strip all remaining non-search characters
+		$text = preg_replace( "/[^{$lc}]+/", " ", $text );
+
+		# Handle 's, s'
+		#
+		#   $text = preg_replace( "/([{$lc}]+)'s /", "\\1 \\1's ", $text );
+		#   $text = preg_replace( "/([{$lc}]+)s' /", "\\1s ", $text );
+		#
+		# These tail-anchored regexps are insanely slow. The worst case comes
+		# when Japanese or Chinese text (ie, no word spacing) is written on
+		# a wiki configured for Western UTF-8 mode. The Unicode characters are
+		# expanded to hex codes and the "words" are very long paragraph-length
+		# monstrosities. On a large page the above regexps may take over 20
+		# seconds *each* on a 1GHz-level processor.
+		#
+		# Following are reversed versions which are consistently fast
+		# (about 3 milliseconds on 1GHz-level processor).
+		#
+		$text = strrev( preg_replace( "/ s'([{$lc}]+)/", " s'\\1 \\1", strrev( $text ) ) );
+		$text = strrev( preg_replace( "/ 's([{$lc}]+)/", " s\\1", strrev( $text ) ) );
+
+		# Strip wiki '' and '''
+		$text = preg_replace( "/''[']*/", " ", $text );
+		wfProfileOut( "$fname-regexps" );
+
+		wfRunHooks( 'SearchUpdate', array( $this->mId, $this->mNamespace, $this->mTitle, &$text ) );
+
+		# Perform the actual update
+		$search->update($this->mId, Title::indexTitle( $this->mNamespace, $this->mTitle ),
+				$text);
+
+		wfProfileOut( $fname );
+	}
+}
+
+/**
+ * Placeholder class
+ * @ingroup Search
+ */
+class SearchUpdateMyISAM extends SearchUpdate {
+	# Inherits everything
+}