wikimedia/mediawiki-extensions-Wikibase

<?php

namespace Wikibase\Repo;

use MediaWiki\Babel\Babel;
use MediaWiki\MediaWikiServices;
use MediaWiki\Registration\ExtensionRegistry;
use MediaWiki\User\User;
use Wikibase\Lib\UserLanguageLookup;

/**
 * Service for looking up the languages understood by a user.
 *
 * The current implementation relies on the Babel extension, but that may change.
 *
 * @license GPL-2.0-or-later
 * @author Daniel Kinzler
 * @author Thiemo Kreuz
 * @author Marius Hoch
 */
class BabelUserLanguageLookup implements UserLanguageLookup {

    /**
     * Local caching since calling the Babel extension can be expensive.
     *
     * @var array[]
     */
    private $babelLanguages = [];

    /**
     * @param User $user The current user.
     *
     * @return string[] List of language codes in the users Babel box.
     */
    protected function getBabelLanguages( User $user ) {
        $key = $user->getId();
        // Lazy initialisation
        if ( !isset( $this->babelLanguages[$key] ) ) {
            // If the extension is installed, grab the languages from the user's Babel box
            if ( ExtensionRegistry::getInstance()->isLoaded( 'Babel' ) && $user->isRegistered() ) {
                $this->babelLanguages[$key] = Babel::getCachedUserLanguages( $user );
            } else {
                $this->babelLanguages[$key] = [];
            }
        }

        return $this->babelLanguages[$key];
    }

    /**
     * Returns a list of languages the user specified in addition to the non-optional interface
     * language.
     * Note: This can contain language codes not actually valid to MediaWiki or valid at all.
     *
     * @param User $user The current user.
     *
     * @return string[] Which language codes the user specified.
     */
    public function getUserSpecifiedLanguages( User $user ) {
        // TODO: If Universal Language Selector (ULS) supports setting additional/alternative
        // languages, these should be used in addition or instead of Babel (also needs API support).

        $languages = $this->getBabelLanguages( $user );

        // All languages in MediaWiki are lower-cased, while Babel doesn't enforce
        // that for regions.
        $languages = array_map( 'strtolower', $languages );

        return $languages;
    }

    /**
     * Collects all languages from all user settings we can reach at this point, in order of
     * preference, duplicates stripped:
     * 1. The interface language from the user's settings
     * 2. All languages in the user's Babel box
     * Note: This can contain language codes not actually valid to MediaWiki or valid at all.
     *
     * @param User $user The current user.
     *
     * @return string[] List of all the user's language codes.
     */
    public function getAllUserLanguages( User $user ) {
        $languages = [];
        $userOptionsLookup = MediaWikiServices::getInstance()->getUserOptionsLookup();
        // Start with the user's UI language
        $userLanguage = $userOptionsLookup->getOption( $user, 'language' );
        if ( $userLanguage !== null ) {
            $languages[] = $userLanguage;
        }

        $userSpecifiedLanguages = $this->getUserSpecifiedLanguages( $user );
        if ( $userSpecifiedLanguages ) {
            $languages = array_merge( $languages, $userSpecifiedLanguages );
            $languages = array_values( array_unique( $languages ) );
        }

        return $languages;
    }

}