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Diffstat (limited to 'www/wiki/includes/search/SearchSuggestionSet.php')
| -rw-r--r-- | www/wiki/includes/search/SearchSuggestionSet.php | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/www/wiki/includes/search/SearchSuggestionSet.php b/www/wiki/includes/search/SearchSuggestionSet.php new file mode 100644 index 00000000..aced5e18 --- /dev/null +++ b/www/wiki/includes/search/SearchSuggestionSet.php @@ -0,0 +1,212 @@ +<?php + +/** + * Search suggestion 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 + */ + +/** + * A set of search suggestions. + * The set is always ordered by score, with the best match first. + */ +class SearchSuggestionSet { + /** + * @var SearchSuggestion[] + */ + private $suggestions = []; + + /** + * + * @var array + */ + private $pageMap = []; + + /** + * Builds a new set of suggestions. + * + * NOTE: the array should be sorted by score (higher is better), + * in descending order. + * SearchSuggestionSet will not try to re-order this input array. + * Providing an unsorted input array is a mistake and will lead to + * unexpected behaviors. + * + * @param SearchSuggestion[] $suggestions (must be sorted by score) + */ + public function __construct( array $suggestions ) { + foreach ( $suggestions as $suggestion ) { + $pageID = $suggestion->getSuggestedTitleID(); + if ( $pageID && empty( $this->pageMap[$pageID] ) ) { + $this->pageMap[$pageID] = true; + } + $this->suggestions[] = $suggestion; + } + } + + /** + * Get the list of suggestions. + * @return SearchSuggestion[] + */ + public function getSuggestions() { + return $this->suggestions; + } + + /** + * Call array_map on the suggestions array + * @param callback $callback + * @return array + */ + public function map( $callback ) { + return array_map( $callback, $this->suggestions ); + } + + /** + * Add a new suggestion at the end. + * If the score of the new suggestion is greater than the worst one, + * the new suggestion score will be updated (worst - 1). + * + * @param SearchSuggestion $suggestion + */ + public function append( SearchSuggestion $suggestion ) { + $pageID = $suggestion->getSuggestedTitleID(); + if ( $pageID && isset( $this->pageMap[$pageID] ) ) { + return; + } + if ( $this->getSize() > 0 && $suggestion->getScore() >= $this->getWorstScore() ) { + $suggestion->setScore( $this->getWorstScore() - 1 ); + } + $this->suggestions[] = $suggestion; + if ( $pageID ) { + $this->pageMap[$pageID] = true; + } + } + + /** + * Add suggestion set to the end of the current one. + * @param SearchSuggestionSet $set + */ + public function appendAll( SearchSuggestionSet $set ) { + foreach ( $set->getSuggestions() as $sugg ) { + $this->append( $sugg ); + } + } + + /** + * Move the suggestion at index $key to the first position + * @param string $key + */ + public function rescore( $key ) { + $removed = array_splice( $this->suggestions, $key, 1 ); + unset( $this->pageMap[$removed[0]->getSuggestedTitleID()] ); + $this->prepend( $removed[0] ); + } + + /** + * Add a new suggestion at the top. If the new suggestion score + * is lower than the best one its score will be updated (best + 1) + * @param SearchSuggestion $suggestion + */ + public function prepend( SearchSuggestion $suggestion ) { + $pageID = $suggestion->getSuggestedTitleID(); + if ( $pageID && isset( $this->pageMap[$pageID] ) ) { + return; + } + if ( $this->getSize() > 0 && $suggestion->getScore() <= $this->getBestScore() ) { + $suggestion->setScore( $this->getBestScore() + 1 ); + } + array_unshift( $this->suggestions, $suggestion ); + if ( $pageID ) { + $this->pageMap[$pageID] = true; + } + } + + /** + * @return float the best score in this suggestion set + */ + public function getBestScore() { + if ( empty( $this->suggestions ) ) { + return 0; + } + return $this->suggestions[0]->getScore(); + } + + /** + * @return float the worst score in this set + */ + public function getWorstScore() { + if ( empty( $this->suggestions ) ) { + return 0; + } + return end( $this->suggestions )->getScore(); + } + + /** + * @return int the number of suggestion in this set + */ + public function getSize() { + return count( $this->suggestions ); + } + + /** + * Remove any extra elements in the suggestions set + * @param int $limit the max size of this set. + */ + public function shrink( $limit ) { + if ( count( $this->suggestions ) > $limit ) { + $this->suggestions = array_slice( $this->suggestions, 0, $limit ); + } + } + + /** + * Builds a new set of suggestion based on a title array. + * Useful when using a backend that supports only Titles. + * + * NOTE: Suggestion scores will be generated. + * + * @param Title[] $titles + * @return SearchSuggestionSet + */ + public static function fromTitles( array $titles ) { + $score = count( $titles ); + $suggestions = array_map( function ( $title ) use ( &$score ) { + return SearchSuggestion::fromTitle( $score--, $title ); + }, $titles ); + return new SearchSuggestionSet( $suggestions ); + } + + /** + * Builds a new set of suggestion based on a string array. + * + * NOTE: Suggestion scores will be generated. + * + * @param string[] $titles + * @return SearchSuggestionSet + */ + public static function fromStrings( array $titles ) { + $score = count( $titles ); + $suggestions = array_map( function ( $title ) use ( &$score ) { + return SearchSuggestion::fromText( $score--, $title ); + }, $titles ); + return new SearchSuggestionSet( $suggestions ); + } + + /** + * @return SearchSuggestionSet an empty suggestion set + */ + public static function emptySuggestionSet() { + return new SearchSuggestionSet( [] ); + } +} |