SpecialLinkSearch: clean up munged query variable handling

[mediawiki.git] / includes / specials / SpecialLinkSearch.php

<?php
/**
 * Implements Special:LinkSearch
 *
 * 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 SpecialPage
 * @author Brion Vibber
 */

/**
 * Special:LinkSearch to search the external-links table.
 * @ingroup SpecialPage
 */
class LinkSearchPage extends QueryPage {
        /** @var array|bool */
        private $mungedQuery = false;

        /**
         * @var PageLinkRenderer
         */
        protected $linkRenderer = null;

        function setParams( $params ) {
                $this->mQuery = $params['query'];
                $this->mNs = $params['namespace'];
                $this->mProt = $params['protocol'];
        }

        function __construct( $name = 'LinkSearch' ) {
                parent::__construct( $name );

                // Since we don't control the constructor parameters, we can't inject services that way.
                // Instead, we initialize services in the execute() method, and allow them to be overridden
                // using the setServices() method.
        }

        /**
         * Initialize or override the PageLinkRenderer LinkSearchPage collaborates with.
         * Useful mainly for testing.
         *
         * @todo query logic and rendering logic should be split and also injected
         *
         * @param PageLinkRenderer $linkRenderer
         */
        public function setPageLinkRenderer(
                PageLinkRenderer $linkRenderer
        ) {
                $this->linkRenderer = $linkRenderer;
        }

        /**
         * Initialize any services we'll need (unless it has already been provided via a setter).
         * This allows for dependency injection even though we don't control object creation.
         */
        private function initServices() {
                if ( !$this->linkRenderer ) {
                        $lang = $this->getContext()->getLanguage();
                        $titleFormatter = new MediaWikiTitleCodec( $lang, GenderCache::singleton() );
                        $this->linkRenderer = new MediaWikiPageLinkRenderer( $titleFormatter );
                }
        }

        function isCacheable() {
                return false;
        }

        function execute( $par ) {
                $this->initServices();

                $this->setHeaders();
                $this->outputHeader();

                $out = $this->getOutput();
                $out->allowClickjacking();

                $request = $this->getRequest();
                $target = $request->getVal( 'target', $par );
                $namespace = $request->getIntOrNull( 'namespace', null );

                $protocols_list = array();
                foreach ( $this->getConfig()->get( 'UrlProtocols' ) as $prot ) {
                        if ( $prot !== '//' ) {
                                $protocols_list[] = $prot;
                        }
                }

                $target2 = $target;
                // Get protocol, default is http://
                $protocol = 'http://';
                $bits = wfParseUrl( $target );
                if ( isset( $bits['scheme'] ) && isset( $bits['delimiter'] ) ) {
                        $protocol = $bits['scheme'] . $bits['delimiter'];
                        // Make sure wfParseUrl() didn't make some well-intended correction in the
                        // protocol
                        if ( strcasecmp( $protocol, substr( $target, 0, strlen( $protocol ) ) ) === 0 ) {
                                $target2 = substr( $target, strlen( $protocol ) );
                        } else {
                                // If it did, let LinkFilter::makeLikeArray() handle this
                                $protocol = '';
                        }
                }

                $out->addWikiMsg(
                        'linksearch-text',
                        '<nowiki>' . $this->getLanguage()->commaList( $protocols_list ) . '</nowiki>',
                        count( $protocols_list )
                );
                $s = Html::openElement(
                        'form',
                        array( 'id' => 'mw-linksearch-form', 'method' => 'get', 'action' => wfScript() )
                ) . "\n" .
                        Html::hidden( 'title', $this->getPageTitle()->getPrefixedDBkey() ) . "\n" .
                        Html::openElement( 'fieldset' ) . "\n" .
                        Html::element( 'legend', array(), $this->msg( 'linksearch' )->text() ) . "\n" .
                        Xml::inputLabel(
                                $this->msg( 'linksearch-pat' )->text(),
                                'target',
                                'target',
                                50,
                                $target,
                                array(
                                        // URLs are always ltr
                                        'dir' => 'ltr',
                                )
                        ) . "\n";

                if ( !$this->getConfig()->get( 'MiserMode' ) ) {
                        $s .= Html::namespaceSelector(
                                array(
                                        'selected' => $namespace,
                                        'all' => '',
                                        'label' => $this->msg( 'linksearch-ns' )->text()
                                ), array(
                                        'name' => 'namespace',
                                        'id' => 'namespace',
                                        'class' => 'namespaceselector',
                                )
                        );
                }

                $s .= Xml::submitButton( $this->msg( 'linksearch-ok' )->text() ) . "\n" .
                        Html::closeElement( 'fieldset' ) . "\n" .
                        Html::closeElement( 'form' ) . "\n";
                $out->addHTML( $s );

                if ( $target != '' ) {
                        $this->setParams( array(
                                'query' => $target2,
                                'namespace' => $namespace,
                                'protocol' => $protocol ) );
                        parent::execute( $par );
                        if ( $this->mungedQuery === false ) {
                                $out->addWikiMsg( 'linksearch-error' );
                        }
                }
        }

        /**
         * Disable RSS/Atom feeds
         * @return bool
         */
        function isSyndicated() {
                return false;
        }

        /**
         * Return an appropriately formatted LIKE query and the clause
         *
         * @param string $query Search pattern to search for
         * @param string $prot Protocol, e.g. 'http://'
         *
         * @return array
         */
        static function mungeQuery( $query, $prot ) {
                $field = 'el_index';
                $dbr = wfGetDB( DB_SLAVE );

                if ( $query === '*' && $prot !== '' ) {
                        // Allow queries like 'ftp://*' to find all ftp links
                        $rv = array( $prot, $dbr->anyString() );
                } else {
                        $rv = LinkFilter::makeLikeArray( $query, $prot );
                }

                if ( $rv === false ) {
                        // LinkFilter doesn't handle wildcard in IP, so we'll have to munge here.
                        $pattern = '/^(:?[0-9]{1,3}\.)+\*\s*$|^(:?[0-9]{1,3}\.){3}[0-9]{1,3}:[0-9]*\*\s*$/';
                        if ( preg_match( $pattern, $query ) ) {
                                $rv = array( $prot . rtrim( $query, " \t*" ), $dbr->anyString() );
                                $field = 'el_to';
                        }
                }

                return array( $rv, $field );
        }

        function linkParameters() {
                $params = array();
                $params['target'] = $this->mProt . $this->mQuery;
                if ( $this->mNs !== null && !$this->getConfig()->get( 'MiserMode' ) ) {
                        $params['namespace'] = $this->mNs;
                }

                return $params;
        }

        function getQueryInfo() {
                $dbr = wfGetDB( DB_SLAVE );
                // strip everything past first wildcard, so that
                // index-based-only lookup would be done
                list( $this->mungedQuery, $clause ) = self::mungeQuery( $this->mQuery, $this->mProt );
                if ( $this->mungedQuery === false ) {
                        // Invalid query; return no results
                        return array( 'tables' => 'page', 'fields' => 'page_id', 'conds' => '0=1' );
                }

                $stripped = LinkFilter::keepOneWildcard( $this->mungedQuery );
                $like = $dbr->buildLike( $stripped );
                $retval = array(
                        'tables' => array( 'page', 'externallinks' ),
                        'fields' => array(
                                'namespace' => 'page_namespace',
                                'title' => 'page_title',
                                'value' => 'el_index',
                                'url' => 'el_to'
                        ),
                        'conds' => array(
                                'page_id = el_from',
                                "$clause $like"
                        ),
                        'options' => array( 'USE INDEX' => $clause )
                );

                if ( $this->mNs !== null && !$this->getConfig()->get( 'MiserMode' ) ) {
                        $retval['conds']['page_namespace'] = $this->mNs;
                }

                return $retval;
        }

        /**
         * Pre-fill the link cache
         *
         * @param IDatabase $db
         * @param ResultWrapper $res
         */
        function preprocessResults( $db, $res ) {
                if ( $res->numRows() > 0 ) {
                        $linkBatch = new LinkBatch();

                        foreach ( $res as $row ) {
                                $linkBatch->add( $row->namespace, $row->title );
                        }

                        $res->seek( 0 );
                        $linkBatch->execute();
                }
        }

        /**
         * @param Skin $skin
         * @param object $result Result row
         * @return string
         */
        function formatResult( $skin, $result ) {
                $title = new TitleValue( (int)$result->namespace, $result->title );
                $pageLink = $this->linkRenderer->renderHtmlLink( $title );

                $url = $result->url;
                $urlLink = Linker::makeExternalLink( $url, $url );

                return $this->msg( 'linksearch-line' )->rawParams( $urlLink, $pageLink )->escaped();
        }

        /**
         * Override to squash the ORDER BY.
         * We do a truncated index search, so the optimizer won't trust
         * it as good enough for optimizing sort. The implicit ordering
         * from the scan will usually do well enough for our needs.
         * @return array
         */
        function getOrderFields() {
                return array();
        }

        protected function getGroupName() {
                return 'redirects';
        }
}