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Diffstat (limited to 'includes/search/SearchEngine.php')
| -rw-r--r-- | includes/search/SearchEngine.php | 1248 |
1 files changed, 1248 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 +} |