wikimedia/mediawiki-extensions-Wikibase

<?php

namespace Wikibase\Lib\Formatters;

use Wikibase\DataModel\Entity\EntityId;
use Wikibase\DataModel\Entity\ItemId;
use Wikibase\DataModel\Services\EntityId\EntityIdFormatter;
use Wikibase\DataModel\Services\Lookup\LabelDescriptionLookup;
use Wikibase\DataModel\Services\Lookup\LabelDescriptionLookupException;
use Wikibase\Lib\Store\EntityTitleLookup;

/**
 * A formatter for exclusive use on client wikis. It expects an entity ID and returns a wikitext
 * snippet, containing a link to a local page as specified by the relevant sitelink, labeled with
 * the label in the local (or a fallback) language. Both the sitelink and the label are optional.
 *
 * @license GPL-2.0-or-later
 * @author Thiemo Kreuz
 */
class EntityIdSiteLinkFormatter implements EntityIdFormatter {

    /**
     * @var EntityTitleLookup
     */
    private $entityTitleLookup;

    /**
     * @var LabelDescriptionLookup
     */
    private $labelLookup;

    public function __construct(
        EntityTitleLookup $entityTitleLookup,
        LabelDescriptionLookup $labelLookup
    ) {
        $this->entityTitleLookup = $entityTitleLookup;
        $this->labelLookup = $labelLookup;
    }

    /**
     * @see EntityIdFormatter::formatEntityId
     *
     * @param EntityId $entityId
     *
     * @return string Wikitext
     */
    public function formatEntityId( EntityId $entityId ) {
        $term = null;

        try {
            $term = $this->labelLookup->getLabel( $entityId );
        } catch ( LabelDescriptionLookupException $ex ) {
        }

        // TODO: Add language fallback indicator
        $label = $term ? wfEscapeWikiText( $term->getText() ) : '';

        if ( $entityId instanceof ItemId ) {
            $title = $this->entityTitleLookup->getTitleForId( $entityId );

            if ( $title !== null ) {
                $pageName = $title->getFullText();
                $optionalLabel = $label === '' ? '' : '|' . $label;

                return '[[' . $pageName . $optionalLabel . ']]';
            }
        }

        return $label === '' ? $entityId->getSerialization() : $label;
    }

}