wiki.techinc.nl/includes/SearchEngine.php
Brion Vibber 366b347795 Follow-up to r45425 -- bug was in MWSearch, not core. It's supposed to be HTML-formatted, but was being built unsafely.
Adding a comment on SearchEngine to clarify that getSuggestionSnippet() returns HTML
2009-01-05 20:46:43 +00:00

1200 lines
30 KiB
PHP

<?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.
*
* @param string $term - Raw search term
* @return SearchResultSet
* @access public
* @abstract
*/
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.
*
* @param string $term - Raw search term
* @return SearchResultSet
* @access public
* @abstract
*/
function searchTitle( $term ) {
return null;
}
/** If this search backend can list/unlist redirects */
function acceptListRedirects() {
return true;
}
/**
* 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 find, or a very slightly close match,
* return the title. If no match, returns NULL.
*
* @param string $term
* @return Title
*/
public static function getNearMatch( $searchterm ) {
global $wgContLang;
$allSearchTerms = array($searchterm);
if($wgContLang->hasVariants()){
$allSearchTerms = array_merge($allSearchTerms,$wgContLang->convertLinkToAllVariants($searchterm));
}
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;
}
# 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 int $limit
* @param int $offset
* @access public
*/
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 array $namespaces
* @access public
*/
function setNamespaces( $namespaces ) {
$this->namespaces = $namespaces;
}
/**
* Parse some common prefixes: all (search everything)
* or namespace names
*
* @param string $query
*/
function replacePrefixes( $query ){
global $wgContLang;
if( strpos($query,':') === false )
return $query; // nothing to do
$parsed = $query;
$allkeyword = wfMsgForContent('searchall').":";
if( strncmp($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) == '')
return $query; // prefix was the whole query
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;
}
}
return $arr;
}
/**
* Extract default namespaces to search from the given user's
* settings, returning a list of index numbers.
*
* @param User $user
* @return array
* @static
*/
public static function userNamespaces( &$user ) {
$arr = array();
foreach( SearchEngine::searchableNamespaces() as $ns => $name ) {
if( $user->getOption( 'searchNs' . $ns ) ) {
$arr[] = $ns;
}
}
return $arr;
}
/**
* Find snippet highlight settings for a given user
*
* @param User $user
* @return array contextlines, contextchars
* @static
*/
public static function userHighlightPrefs( &$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
* @static
*/
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 unknown_type $namespaces
*/
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;
}
/**
* An array of "project" namespaces indexes typically searched
* by logged-in users
*
* @return array
* @static
*/
public static function projectNamespaces() {
global $wgNamespacesToBeSearchedDefault, $wgNamespacesToBeSearchedProject;
return array_keys( $wgNamespacesToBeSearchedProject, true );
}
/**
* An array of "project" namespaces indexes typically searched
* by logged-in users in addition to the default namespaces
*
* @return array
* @static
*/
public static function defaultAndProjectNamespaces() {
global $wgNamespacesToBeSearchedDefault, $wgNamespacesToBeSearchedProject;
return array_keys( $wgNamespacesToBeSearchedDefault +
$wgNamespacesToBeSearchedProject, true);
}
/**
* Return a 'cleaned up' search string
*
* @return string
* @access public
*/
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.
*
* @param int $id
* @param string $title
* @param string $text
* @abstract
*/
function update( $id, $title, $text ) {
// no-op
}
/**
* Update a search index record's title only.
* Title should be pre-processed.
*
* @param int $id
* @param string $title
* @abstract
*/
function updateTitle( $id, $title ) {
// no-op
}
/**
* Get OpenSearch suggestion template
*
* @return string
* @static
*/
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
* @static
*/
public static function getMWSuggestTemplate() {
global $wgMWSuggestTemplate, $wgServer, $wgScriptPath;
if($wgMWSuggestTemplate)
return $wgMWSuggestTemplate;
else
return $wgServer . $wgScriptPath . '/api.php?action=opensearch&search={searchTerms}&namespace={namespaces}';
}
}
/**
* @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.
*
* @return array
* @access public
* @abstract
*/
function termMatches() {
return array();
}
function numRows() {
return 0;
}
/**
* Return true if results are included in this result set.
* @return bool
* @abstract
*/
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 int
* @access public
*/
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 bool
* @access public
*/
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.
* @return SearchResult
* @access public
* @abstract
*/
function next() {
return false;
}
/**
* Frees the result set, if applicable.
* @ access public
*/
function free() {
// ...
}
}
/**
* @ingroup Search
*/
class SearchResultTooMany {
## Some search engines may bail out if too many matches are found
}
/**
* @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( $this->mTitle );
}
}
/**
* Check if this is result points to an invalid title
*
* @return boolean
* @access public
*/
function isBrokenTitle(){
if( is_null($this->mTitle) )
return true;
return false;
}
/**
* Check if target page is missing, happens when index is out of date
*
* @return boolean
* @access public
*/
function isMissingRevision(){
return !$this->mRevision && !$this->mImage;
}
/**
* @return Title
* @access public
*/
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 array $terms terms to highlight
* @return string highlighted text snippet, null (and not '') if not supported
*/
function getTextSnippet($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 array $terms terms to highlight
* @return string highlighted title, '' if not supported
*/
function getTitleSnippet($terms){
return '';
}
/**
* @param array $terms terms to highlight
* @return string highlighted redirect name (redirect to this page), '' if none or not supported
*/
function getRedirectSnippet($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 int number of words
*/
function getWordCount(){
$this->initText();
return str_word_count( $this->mText );
}
/**
* @return int size in bytes
*/
function getByteSize(){
$this->initText();
return strlen( $this->mText );
}
/**
* @return boolean if hit has related articles
*/
function hasRelated(){
return false;
}
/**
* @return 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 string $text
* @param array $terms Terms to highlight (unescaped)
* @param int $contextlines
* @param int $contextchars
* @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 array $extracts index -> $line
* @param int $count
* @param string $text
*/
function splitAndAdd(&$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 unknown_type $matches
*/
function caseCallback($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 string $text
* @param int $start
* @param int $end
* @param int $posStart (out) actual start position
* @param int $posEnd (out) actual end position
* @return string
*/
function extract($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 string $text
* @param int $point
* @param int $offset to found index
* @return int nearest nonletter index, or beginning of utf8 char if none
*/
function position($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 string $pattern regexp for matching lines
* @param array $extracts extracts to search
* @param int $linesleft number of extracts to make
* @param int $contextchars length of snippet
* @param array $out map for highlighted snippets
* @param array $offsets 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 array $matches
*/
function linkReplace($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 string $text
* @param array $terms
* @param int $contextlines
* @param int $contextchars
* @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.
* @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
}