SpecialReplaceText.php

Go to the documentation of this file.

<?php
use MediaWiki\MediaWikiServices;
 
class SpecialReplaceText extends SpecialPage {
    private $target;
    private $replacement;
    private $use_regex;
    private $category;
    private $prefix;
    private $edit_pages;
    private $move_pages;
    private $selected_namespaces;
    private $doAnnounce;
 
    public function __construct() {
        parent::__construct( 'ReplaceText', 'replacetext' );
    }
 
    public function doesWrites() {
        return true;
    }
 
    function execute( $query ) {
        global $wgCompressRevisions, $wgExternalStores;
 
        if ( !$this->getUser()->isAllowed( 'replacetext' ) ) {
            throw new PermissionsError( 'replacetext' );
        }
 
        $out = $this->getOutput();
        // Replace Text can't be run with certain settings, due to the
        // changes they make to the DB storage setup.
        if ( $wgCompressRevisions ) {
            $errorMsg = "Error: text replacements cannot be run if \$wgCompressRevisions is set to true.";
            $out->addWikiTextAsContent( "<div class=\"errorbox\">$errorMsg</div>" );
            return;
        }
        if ( !empty( $wgExternalStores ) ) {
            $errorMsg = "Error: text replacements cannot be run if \$wgExternalStores is non-empty.";
            $out->addWikiTextAsContent( "<div class=\"errorbox\">$errorMsg</div>" );
            return;
        }
 
        $this->setHeaders();
        if ( !is_null( $out->getResourceLoader()->getModule( 'mediawiki.special' ) ) ) {
            $out->addModuleStyles( 'mediawiki.special' );
        }
        $this->doSpecialReplaceText();
    }
 
    function getSelectedNamespaces() {
        if ( class_exists( MediaWikiServices::class ) ) {
            // MW 1.27+
            $all_namespaces = MediaWikiServices::getInstance()->getSearchEngineConfig()
                ->searchableNamespaces();
        } else {
            $all_namespaces = SearchEngine::searchableNamespaces();
        }
        $selected_namespaces = [];
        foreach ( $all_namespaces as $ns => $name ) {
            if ( $this->getRequest()->getCheck( 'ns' . $ns ) ) {
                $selected_namespaces[] = $ns;
            }
        }
        return $selected_namespaces;
    }
 
    function doSpecialReplaceText() {
        $out = $this->getOutput();
        $request = $this->getRequest();
 
        $this->target = $request->getText( 'target' );
        $this->replacement = $request->getText( 'replacement' );
        $this->use_regex = $request->getBool( 'use_regex' );
        $this->category = $request->getText( 'category' );
        $this->prefix = $request->getText( 'prefix' );
        $this->edit_pages = $request->getBool( 'edit_pages' );
        $this->move_pages = $request->getBool( 'move_pages' );
        $this->doAnnounce = $request->getBool( 'doAnnounce' );
        $this->selected_namespaces = $this->getSelectedNamespaces();
 
        if ( $request->getCheck( 'continue' ) && $this->target === '' ) {
            $this->showForm( 'replacetext_givetarget' );
            return;
        }
 
        if ( $request->getCheck( 'replace' ) ) {
 
            // check for CSRF
            $user = $this->getUser();
            if ( !$user->matchEditToken( $request->getVal( 'token' ) ) ) {
                $out->addWikiMsg( 'sessionfailure' );
                return;
            }
 
            $jobs = $this->createJobsForTextReplacements();
            JobQueueGroup::singleton()->push( $jobs );
 
            $count = $this->getLanguage()->formatNum( count( $jobs ) );
            $out->addWikiMsg(
                'replacetext_success',
                "<code><nowiki>{$this->target}</nowiki></code>",
                "<code><nowiki>{$this->replacement}</nowiki></code>",
                $count
            );
 
            // Link back
            $out->addHTML(
                ReplaceTextUtils::link(
                    $this->getPageTitle(),
                    $this->msg( 'replacetext_return' )->text()
                )
            );
            return;
        }
 
        if ( $request->getCheck( 'target' ) ) {
            // check for CSRF
            $user = $this->getUser();
            if ( !$user->matchEditToken( $request->getVal( 'token' ) ) ) {
                $out->addWikiMsg( 'sessionfailure' );
                return;
            }
 
            // first, check that at least one namespace has been
            // picked, and that either editing or moving pages
            // has been selected
            if ( count( $this->selected_namespaces ) == 0 ) {
                $this->showForm( 'replacetext_nonamespace' );
                return;
            }
            if ( !$this->edit_pages && !$this->move_pages ) {
                $this->showForm( 'replacetext_editormove' );
                return;
            }
 
            // If user is replacing text within pages...
            $titles_for_edit = $titles_for_move = $unmoveable_titles = [];
            if ( $this->edit_pages ) {
                $titles_for_edit = $this->getTitlesForEditingWithContext();
            }
            if ( $this->move_pages ) {
                list( $titles_for_move, $unmoveable_titles ) = $this->getTitlesForMoveAndUnmoveableTitles();
            }
 
            // If no results were found, check to see if a bad
            // category name was entered.
            if ( count( $titles_for_edit ) == 0 && count( $titles_for_move ) == 0 ) {
                $bad_cat_name = false;
 
                if ( !empty( $this->category ) ) {
                    $category_title = Title::makeTitleSafe( NS_CATEGORY, $this->category );
                    if ( !$category_title->exists() ) {
                        $bad_cat_name = true;
                    }
                }
 
                if ( $bad_cat_name ) {
                    $link = ReplaceTextUtils::link(
                        $category_title,
                        ucfirst( $this->category )
                    );
                    $out->addHTML(
                        $this->msg( 'replacetext_nosuchcategory' )->rawParams( $link )->escaped()
                    );
                } else {
                    if ( $this->edit_pages ) {
                        $out->addWikiMsg(
                            'replacetext_noreplacement', "<code><nowiki>{$this->target}</nowiki></code>"
                        );
                    }
 
                    if ( $this->move_pages ) {
                        $out->addWikiMsg( 'replacetext_nomove', "<code><nowiki>{$this->target}</nowiki></code>" );
                    }
                }
                // link back to starting form
                $out->addHTML(
                    '<p>' .
                    ReplaceTextUtils::link(
                        $this->getPageTitle(),
                        $this->msg( 'replacetext_return' )->text()
                    )
                    . '</p>'
                );
            } else {
                $warning_msg = $this->getAnyWarningMessageBeforeReplace( $titles_for_edit, $titles_for_move );
                if ( !is_null( $warning_msg ) ) {
                    $out->addWikiTextAsContent(
                        "<div class=\"errorbox\">$warning_msg</div><br clear=\"both\" />"
                    );
                }
 
                $this->pageListForm( $titles_for_edit, $titles_for_move, $unmoveable_titles );
            }
            return;
        }
 
        // If we're still here, show the starting form.
        $this->showForm();
    }
 
    function createJobsForTextReplacements() {
        global $wgReplaceTextUser;
 
        $replacement_params = [];
        if ( $wgReplaceTextUser != null ) {
            $user = User::newFromName( $wgReplaceTextUser );
        } else {
            $user = $this->getUser();
        }
 
        $replacement_params['user_id'] = $user->getId();
        $replacement_params['target_str'] = $this->target;
        $replacement_params['replacement_str'] = $this->replacement;
        $replacement_params['use_regex'] = $this->use_regex;
        $replacement_params['edit_summary'] = $this->msg(
            'replacetext_editsummary',
            $this->target, $this->replacement
        )->inContentLanguage()->plain();
        $replacement_params['create_redirect'] = false;
        $replacement_params['watch_page'] = false;
        $replacement_params['doAnnounce'] = $this->doAnnounce;
 
        $request = $this->getRequest();
        foreach ( $request->getValues() as $key => $value ) {
            if ( $key == 'create-redirect' && $value == '1' ) {
                $replacement_params['create_redirect'] = true;
            } elseif ( $key == 'watch-pages' && $value == '1' ) {
                $replacement_params['watch_page'] = true;
            }
        }
 
        $jobs = [];
        foreach ( $request->getValues() as $key => $value ) {
            if ( $value == '1' && $key !== 'replace' && $key !== 'use_regex' ) {
                if ( strpos( $key, 'move-' ) !== false ) {
                    $title = Title::newFromID( substr( $key, 5 ) );
                    $replacement_params['move_page'] = true;
                } else {
                    $title = Title::newFromID( $key );
                }
                if ( $title !== null ) {
                    $jobs[] = new ReplaceTextJob( $title, $replacement_params );
                }
            }
        }
 
        return $jobs;
    }
 
    function getTitlesForEditingWithContext() {
        $titles_for_edit = [];
 
        $res = ReplaceTextSearch::doSearchQuery(
            $this->target,
            $this->selected_namespaces,
            $this->category,
            $this->prefix,
            $this->use_regex
        );
 
        foreach ( $res as $row ) {
            $title = Title::makeTitleSafe( $row->page_namespace, $row->page_title );
            if ( $title == null ) {
                continue;
            }
            $context = $this->extractContext( $row->old_text, $this->target, $this->use_regex );
            $titles_for_edit[] = [ $title, $context ];
        }
 
        return $titles_for_edit;
    }
 
    function getTitlesForMoveAndUnmoveableTitles() {
        $titles_for_move = [];
        $unmoveable_titles = [];
 
        $res = ReplaceTextSearch::getMatchingTitles(
            $this->target,
            $this->selected_namespaces,
            $this->category,
            $this->prefix,
            $this->use_regex
        );
 
        foreach ( $res as $row ) {
            $title = Title::makeTitleSafe( $row->page_namespace, $row->page_title );
            if ( $title == null ) {
                continue;
            }
 
            $new_title = ReplaceTextSearch::getReplacedTitle(
                $title,
                $this->target,
                $this->replacement,
                $this->use_regex
            );
 
            $mvPage = new MovePage( $title, $new_title );
            $moveStatus = $mvPage->isValidMove();
            $permissionStatus = $mvPage->checkPermissions( $this->getUser(), null );
 
            if ( $permissionStatus->isOK() && $moveStatus->isOK() ) {
                $titles_for_move[] = $title;
            } else {
                $unmoveable_titles[] = $title;
            }
        }
 
        return [ $titles_for_move, $unmoveable_titles ];
    }
 
    function getAnyWarningMessageBeforeReplace( $titles_for_edit, $titles_for_move ) {
        if ( $this->replacement === '' ) {
            return $this->msg( 'replacetext_blankwarning' )->text();
        } elseif ( $this->use_regex ) {
            // If it's a regex, don't bother checking for existing
            // pages - if the replacement string includes wildcards,
            // it's a meaningless check.
            return null;
        } elseif ( count( $titles_for_edit ) > 0 ) {
            $res = ReplaceTextSearch::doSearchQuery(
                $this->replacement,
                $this->selected_namespaces,
                $this->category,
                $this->prefix,
                $this->use_regex
            );
            $count = $res->numRows();
            if ( $count > 0 ) {
                return $this->msg( 'replacetext_warning' )->numParams( $count )
                    ->params( "<code><nowiki>{$this->replacement}</nowiki></code>" )->text();
            }
        } elseif ( count( $titles_for_move ) > 0 ) {
            $res = ReplaceTextSearch::getMatchingTitles(
                $this->replacement,
                $this->selected_namespaces,
                $this->category,
                $this->prefix,
                $this->use_regex
            );
            $count = $res->numRows();
            if ( $count > 0 ) {
                return $this->msg( 'replacetext_warning' )->numParams( $count )
                    ->params( $this->replacement )->text();
            }
        }
 
        return null;
    }
 
    function showForm( $warning_msg = null ) {
        $out = $this->getOutput();
 
        $out->addHTML(
            Xml::openElement(
                'form',
                [
                    'id' => 'powersearch',
                    'action' => $this->getPageTitle()->getFullURL(),
                    'method' => 'post'
                ]
            ) . "\n" .
            Html::hidden( 'title', $this->getPageTitle()->getPrefixedText() ) .
            Html::hidden( 'continue', 1 ) .
            Html::hidden( 'token', $out->getUser()->getEditToken() )
        );
        if ( is_null( $warning_msg ) ) {
            $out->addWikiMsg( 'replacetext_docu' );
        } else {
            $out->wrapWikiMsg(
                "<div class=\"errorbox\">\n$1\n</div><br clear=\"both\" />",
                $warning_msg
            );
        }
 
        $out->addHTML( '<table><tr><td style="vertical-align: top;">' );
        $out->addWikiMsg( 'replacetext_originaltext' );
        $out->addHTML( '</td><td>' );
        // 'width: auto' style is needed to override MediaWiki's
        // normal 'width: 100%', which causes the textarea to get
        // zero width in IE
        $out->addHTML(
            Xml::textarea( 'target', $this->target, 100, 5, [ 'style' => 'width: auto;' ] )
        );
        $out->addHTML( '</td></tr><tr><td style="vertical-align: top;">' );
        $out->addWikiMsg( 'replacetext_replacementtext' );
        $out->addHTML( '</td><td>' );
        $out->addHTML(
            Xml::textarea( 'replacement', $this->replacement, 100, 5, [ 'style' => 'width: auto;' ] )
        );
        $out->addHTML( '</td></tr></table>' );
 
        // MSSQL/SQLServer and SQLite unfortunately lack a REGEXP
        // function or operator by default, so disable regex(p)
        // searches for both these DB types.
        $dbr = wfGetDB( DB_REPLICA );
        if ( $dbr->getType() != 'sqlite' && $dbr->getType() != 'mssql' ) {
            $out->addHTML( Xml::tags( 'p', null,
                    Xml::checkLabel(
                        $this->msg( 'replacetext_useregex' )->text(),
                        'use_regex', 'use_regex'
                    )
                ) . "\n" .
                Xml::element( 'p',
                    [ 'style' => 'font-style: italic' ],
                    $this->msg( 'replacetext_regexdocu' )->text()
                )
            );
        }
 
        // The interface is heavily based on the one in Special:Search.
        if ( class_exists( MediaWikiServices::class ) ) {
            // MW 1.27+
            $namespaces = MediaWikiServices::getInstance()->getSearchEngineConfig()
                ->searchableNamespaces();
        } else {
            $namespaces = SearchEngine::searchableNamespaces();
        }
        $tables = $this->namespaceTables( $namespaces );
        $out->addHTML(
            "<div class=\"mw-search-formheader\"></div>\n" .
            "<fieldset id=\"mw-searchoptions\">\n" .
            Xml::tags( 'h4', null, $this->msg( 'powersearch-ns' )->parse() )
        );
        // The ability to select/unselect groups of namespaces in the
        // search interface exists only in some skins, like Vector -
        // check for the presence of the 'powersearch-togglelabel'
        // message to see if we can use this functionality here.
        if ( $this->msg( 'powersearch-togglelabel' )->isDisabled() ) {
            // do nothing
        } else {
            $out->addHTML(
                Html::element(
                    'div',
                    [ 'id' => 'mw-search-togglebox' ]
                )
            );
        }
        $out->addHTML(
            Xml::element( 'div', [ 'class' => 'divider' ], '', false ) .
            "$tables\n</fieldset>"
        );
        // @todo FIXME: raw html messages
        $category_search_label = $this->msg( 'replacetext_categorysearch' )->escaped();
        $prefix_search_label = $this->msg( 'replacetext_prefixsearch' )->escaped();
        $rcPage = SpecialPage::getTitleFor( 'Recentchanges' );
        $rcPageName = $rcPage->getPrefixedText();
        $out->addHTML(
            "<fieldset id=\"mw-searchoptions\">\n" .
            Xml::tags( 'h4', null, $this->msg( 'replacetext_optionalfilters' )->parse() ) .
            Xml::element( 'div', [ 'class' => 'divider' ], '', false ) .
            "<p>$category_search_label\n" .
            Xml::input( 'category', 20, $this->category, [ 'type' => 'text' ] ) . '</p>' .
            "<p>$prefix_search_label\n" .
            Xml::input( 'prefix', 20, $this->prefix, [ 'type' => 'text' ] ) . '</p>' .
            "</fieldset>\n" .
            "<p>\n" .
            Xml::checkLabel(
                $this->msg( 'replacetext_editpages' )->text(), 'edit_pages', 'edit_pages', true
            ) . '<br />' .
            Xml::checkLabel(
                $this->msg( 'replacetext_movepages' )->text(), 'move_pages', 'move_pages'
            ) . '<br />' .
            Xml::checkLabel(
                $this->msg( 'replacetext_announce', $rcPageName )->text(), 'doAnnounce', 'doAnnounce', true
            ) .
            "</p>\n" .
            Xml::submitButton( $this->msg( 'replacetext_continue' )->text() ) .
            Xml::closeElement( 'form' )
        );
        $out->addModules( 'ext.ReplaceText' );
    }
 
    function namespaceTables( $namespaces, $rowsPerTable = 3 ) {
        global $wgContLang;
        // Group namespaces into rows according to subject.
        // Try not to make too many assumptions about namespace numbering.
        $rows = [];
        $tables = "";
        foreach ( $namespaces as $ns => $name ) {
            $subj = MWNamespace::getSubject( $ns );
            if ( !array_key_exists( $subj, $rows ) ) {
                $rows[$subj] = "";
            }
            $name = str_replace( '_', ' ', $name );
            if ( '' == $name ) {
                $name = $this->msg( 'blanknamespace' )->text();
            }
            $rows[$subj] .= Xml::openElement( 'td', [ 'style' => 'white-space: nowrap' ] ) .
                Xml::checkLabel( $name, "ns{$ns}", "mw-search-ns{$ns}", in_array( $ns, $namespaces ) ) .
                Xml::closeElement( 'td' ) . "\n";
        }
        $rows = array_values( $rows );
        $numRows = count( $rows );
        // Lay out namespaces in multiple floating two-column tables so they'll
        // be arranged nicely while still accommodating different screen widths
        // Float to the right on RTL wikis
        $tableStyle = $wgContLang->isRTL() ?
            'float: right; margin: 0 0 0em 1em' : 'float: left; margin: 0 1em 0em 0';
        // Build the final HTML table...
        for ( $i = 0; $i < $numRows; $i += $rowsPerTable ) {
            $tables .= Xml::openElement( 'table', [ 'style' => $tableStyle ] );
            for ( $j = $i; $j < $i + $rowsPerTable && $j < $numRows; $j++ ) {
                $tables .= "<tr>\n" . $rows[$j] . "</tr>";
            }
            $tables .= Xml::closeElement( 'table' ) . "\n";
        }
        return $tables;
    }
 
    function pageListForm( $titles_for_edit, $titles_for_move, $unmoveable_titles ) {
        global $wgLang;
 
        $out = $this->getOutput();
 
        $formOpts = [
            'id' => 'choose_pages',
            'method' => 'post',
            'action' => $this->getPageTitle()->getFullUrl()
        ];
        $out->addHTML(
            Xml::openElement( 'form', $formOpts ) . "\n" .
            Html::hidden( 'title', $this->getPageTitle()->getPrefixedText() ) .
            Html::hidden( 'target', $this->target ) .
            Html::hidden( 'replacement', $this->replacement ) .
            Html::hidden( 'use_regex', $this->use_regex ) .
            Html::hidden( 'move_pages', $this->move_pages ) .
            Html::hidden( 'edit_pages', $this->edit_pages ) .
            Html::hidden( 'doAnnounce', $this->doAnnounce ) .
            Html::hidden( 'replace', 1 ) .
            Html::hidden( 'token', $out->getUser()->getEditToken() )
        );
 
        foreach ( $this->selected_namespaces as $ns ) {
            $out->addHTML( Html::hidden( 'ns' . $ns, 1 ) );
        }
 
        $out->addModules( "ext.ReplaceText" );
        $out->addModuleStyles( "ext.ReplaceTextStyles" );
        // Needed for bolding of search term.
        $out->addModuleStyles( "mediawiki.special.search.styles" );
 
        if ( count( $titles_for_edit ) > 0 ) {
            $out->addWikiMsg(
                'replacetext_choosepagesforedit',
                "<code><nowiki>{$this->target}</nowiki></code>",
                "<code><nowiki>{$this->replacement}</nowiki></code>",
                $wgLang->formatNum( count( $titles_for_edit ) )
            );
 
            foreach ( $titles_for_edit as $title_and_context ) {
                list( $title, $context ) = $title_and_context;
                $out->addHTML(
                    Xml::check( $title->getArticleID(), true ) .
                    ReplaceTextUtils::link( $title ) .
                    " - <small>$context</small><br />\n"
                );
            }
            $out->addHTML( '<br />' );
        }
 
        if ( count( $titles_for_move ) > 0 ) {
            $out->addWikiMsg(
                'replacetext_choosepagesformove',
                $this->target, $this->replacement, $wgLang->formatNum( count( $titles_for_move ) )
            );
            foreach ( $titles_for_move as $title ) {
                $out->addHTML(
                    Xml::check( 'move-' . $title->getArticleID(), true ) .
                    ReplaceTextUtils::link( $title ) . "<br />\n"
                );
            }
            $out->addHTML( '<br />' );
            $out->addWikiMsg( 'replacetext_formovedpages' );
            $rcPage = SpecialPage::getTitleFor( 'Recentchanges' );
            $rcPageName = $rcPage->getPrefixedText();
            $out->addHTML(
                Xml::checkLabel(
                    $this->msg( 'replacetext_savemovedpages' )->text(),
                        'create-redirect', 'create-redirect', true ) . "<br />\n" .
                Xml::checkLabel(
                    $this->msg( 'replacetext_watchmovedpages' )->text(),
                    'watch-pages', 'watch-pages', false ) . '<br />'
            );
            $out->addHTML( '<br />' );
        }
 
        $out->addHTML(
            "<br />\n" .
            Xml::submitButton( $this->msg( 'replacetext_replace' )->text() ) . "\n"
        );
 
        // Only show "invert selections" link if there are more than
        // five pages.
        if ( count( $titles_for_edit ) + count( $titles_for_move ) > 5 ) {
            $buttonOpts = [
                'type' => 'button',
                'value' => $this->msg( 'replacetext_invertselections' )->text(),
                'disabled' => true,
                'id' => 'replacetext-invert',
                'class' => 'mw-replacetext-invert'
            ];
 
            $out->addHTML(
                Xml::element( 'input', $buttonOpts )
            );
        }
 
        $out->addHTML( '</form>' );
 
        if ( count( $unmoveable_titles ) > 0 ) {
            $out->addWikiMsg( 'replacetext_cannotmove', $wgLang->formatNum( count( $unmoveable_titles ) ) );
            $text = "<ul>\n";
            foreach ( $unmoveable_titles as $title ) {
                $text .= "<li>" . ReplaceTextUtils::link( $title ) . "<br />\n";
            }
            $text .= "</ul>\n";
            $out->addHTML( $text );
        }
    }
 
    function extractContext( $text, $target, $use_regex = false ) {
        global $wgLang;
 
        $cw = $this->getUser()->getOption( 'contextchars', 40 );
 
        // Get all indexes
        if ( $use_regex ) {
            preg_match_all( "/$target/Uu", $text, $matches, PREG_OFFSET_CAPTURE );
        } else {
            $targetq = preg_quote( $target, '/' );
            preg_match_all( "/$targetq/", $text, $matches, PREG_OFFSET_CAPTURE );
        }
 
        $poss = [];
        foreach ( $matches[0] as $_ ) {
            $poss[] = $_[1];
        }
 
        $cuts = [];
        // @codingStandardsIgnoreStart
        for ( $i = 0; $i < count( $poss ); $i++ ) {
        // @codingStandardsIgnoreEnd
            $index = $poss[$i];
            $len = strlen( $target );
 
            // Merge to the next if possible
            while ( isset( $poss[$i + 1] ) ) {
                if ( $poss[$i + 1] < $index + $len + $cw * 2 ) {
                    $len += $poss[$i + 1] - $poss[$i];
                    $i++;
                } else {
                    // Can't merge, exit the inner loop
                    break;
                }
            }
            $cuts[] = [ $index, $len ];
        }
 
        $context = '';
        foreach ( $cuts as $_ ) {
            list( $index, $len, ) = $_;
            $contextBefore = substr( $text, 0, $index );
            $contextAfter = substr( $text, $index + $len );
            if ( !is_callable( [ $wgLang, 'truncateForDatabase' ] ) ) {
                // Backwards compatibility code; remove once MW 1.30 is
                // no longer supported.
                $contextBefore =
                    $wgLang->truncate( $contextBefore, - $cw, '...', false );
                $contextAfter =
                    $wgLang->truncate( $contextAfter, $cw, '...', false );
            } else {
                $contextBefore =
                    $wgLang->truncateForDatabase( $contextBefore, - $cw, '...', false );
                $contextAfter =
                    $wgLang->truncateForDatabase( $contextAfter, $cw, '...', false );
            }
            $context .= $this->convertWhiteSpaceToHTML( $contextBefore );
            $snippet = $this->convertWhiteSpaceToHTML( substr( $text, $index, $len ) );
            if ( $use_regex ) {
                $targetStr = "/$target/Uu";
            } else {
                $targetq = preg_quote( $this->convertWhiteSpaceToHTML( $target ), '/' );
                $targetStr = "/$targetq/i";
            }
            $context .= preg_replace( $targetStr, '<span class="searchmatch">\0</span>', $snippet );
 
            $context .= $this->convertWhiteSpaceToHTML( $contextAfter );
        }
        return $context;
    }
 
    private function convertWhiteSpaceToHTML( $message ) {
        $msg = htmlspecialchars( $message );
        $msg = preg_replace( '/^ /m', '&#160; ', $msg );
        $msg = preg_replace( '/ $/m', ' &#160;', $msg );
        $msg = preg_replace( '/  /', '&#160; ', $msg );
        # $msg = str_replace( "\n", '<br />', $msg );
        return $msg;
    }
 
    protected function getGroupName() {
        return 'wiki';
    }
}