wikimedia/mediawiki-extensions-Wikibase

<?php declare( strict_types=1 );

namespace Wikibase\Repo\RestApi\Infrastructure\DataAccess;

use Wikibase\DataModel\Statement\Statement as StatementWriteModel;
use Wikibase\DataModel\Statement\StatementGuid;
use Wikibase\Repo\RestApi\Domain\ReadModel\Statement;
use Wikibase\Repo\RestApi\Domain\Services\StatementReadModelConverter;
use Wikibase\Repo\RestApi\Domain\Services\StatementRetriever;
use Wikibase\Repo\RestApi\Domain\Services\StatementWriteModelRetriever;

/**
 * @license GPL-2.0-or-later
 */
class EntityRevisionLookupStatementRetriever implements StatementRetriever, StatementWriteModelRetriever {

    private StatementSubjectRetriever $statementSubjectRetriever;
    private StatementReadModelConverter $statementReadModelConverter;

    public function __construct(
        StatementSubjectRetriever $statementSubjectRetriever,
        StatementReadModelConverter $statementReadModelConverter
    ) {
        $this->statementSubjectRetriever = $statementSubjectRetriever;
        $this->statementReadModelConverter = $statementReadModelConverter;
    }

    public function getStatement( StatementGuid $statementId ): ?Statement {
        $statement = $this->getStatementWriteModel( $statementId );
        return $statement ? $this->statementReadModelConverter->convert( $statement ) : null;
    }

    public function getStatementWriteModel( StatementGuid $statementId ): ?StatementWriteModel {
        $subjectId = $statementId->getEntityId();
        $subject = $this->statementSubjectRetriever->getStatementSubject( $subjectId );

        if ( $subject === null ) {
            return null;
        }

        return $subject->getStatements()->getFirstStatementWithGuid( (string)$statementId );
    }

}