wikimedia/mediawiki-extensions-Wikibase

<?php

namespace Wikibase\Lib;

/**
 * Provide languages supported as content languages by removing values in one ContentLanguages
 * from another ContentLanguages
 *
 * @license GPL-2.0-or-later
 * @author Adrian Heine <adrian.heine@wikimedia.de>
 */
class DifferenceContentLanguages implements ContentLanguages {

    /**
     * @var ContentLanguages
     */
    private $all;

    /**
     * @var ContentLanguages
     */
    private $excluded;

    /**
     * @var string[]|null Array of language codes
     */
    private $languageCodes = null;

    public function __construct( ContentLanguages $all, ContentLanguages $excluded ) {
        $this->all = $all;
        $this->excluded = $excluded;
    }

    /**
     * @return string[] Array of language codes supported as content language
     */
    public function getLanguages() {
        return $this->getLanguageCodes();
    }

    /**
     * @param string $languageCode
     *
     * @return bool
     */
    public function hasLanguage( $languageCode ) {
        return in_array( $languageCode, $this->getLanguageCodes() );
    }

    /**
     * @return string[] Array of language codes
     */
    private function getLanguageCodes() {
        if ( $this->languageCodes === null ) {
            $this->languageCodes = array_values(
                array_diff( $this->all->getLanguages(), $this->excluded->getLanguages() )
            );
        }

        return $this->languageCodes;
    }

}