Merge "Don't let LinkCache grow indefinitely"

[mediawiki.git] / includes / search / SearchResultSet.php

<?php
/**
 * Search result sets
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 * @ingroup Search
 */

/**
 * @ingroup Search
 */
class SearchResultSet {
        protected $containedSyntax = false;

        public function __construct( $containedSyntax = false ) {
                $this->containedSyntax = $containedSyntax;
        }

        /**
         * 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;
        }

        /**
         * 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
         */
        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
         */
        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 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 bool
         */
        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() {
                // ...
        }

        /**
         * Did the search contain search syntax?  If so, Special:Search won't offer
         * the user a link to a create a page named by the search string because the
         * name would contain the search syntax.
         * @return bool
         */
        public function searchContainedSyntax() {
                return $this->containedSyntax;
        }
}

/**
 * This class is used for different SQL-based search engines shipped with MediaWiki
 * @ingroup Search
 */
class SqlSearchResultSet extends SearchResultSet {
        protected $resultSet;
        protected $terms;
        protected $totalHits;

        function __construct( $resultSet, $terms, $total = null ) {
                $this->resultSet = $resultSet;
                $this->terms = $terms;
                $this->totalHits = $total;
        }

        function termMatches() {
                return $this->terms;
        }

        function numRows() {
                if ( $this->resultSet === false ) {
                        return false;
                }

                return $this->resultSet->numRows();
        }

        function next() {
                if ( $this->resultSet === false ) {
                        return false;
                }

                $row = $this->resultSet->fetchObject();
                if ( $row === false ) {
                        return false;
                }

                return SearchResult::newFromTitle(
                        Title::makeTitle( $row->page_namespace, $row->page_title )
                );
        }

        function free() {
                if ( $this->resultSet === false ) {
                        return false;
                }

                $this->resultSet->free();
        }

        function getTotalHits() {
                if ( !is_null( $this->totalHits ) ) {
                        return $this->totalHits;
                } else {
                        // Special:Search expects a number here.
                        return $this->numRows();
                }
        }
}

/**
 * A SearchResultSet wrapper for SearchEngine::getNearMatch
 */
class SearchNearMatchResultSet extends SearchResultSet {
        private $fetched = false;

        /**
         * @param Title|null $match Title if matched, else null
         */
        public function __construct( $match ) {
                $this->result = $match;
        }

        public function numRows() {
                return $this->result ? 1 : 0;
        }

        public function next() {
                if ( $this->fetched || !$this->result ) {
                        return false;
                }
                $this->fetched = true;
                return SearchResult::newFromTitle( $this->result );
        }
}