wikimedia/mediawiki-extensions-Wikibase

<?php
declare( strict_types=1 );

namespace Wikibase\Lib;

/**
 * Thin wrapper around EntityTypeDefinitions::SUB_ENTITY_TYPES
 *
 * @license GPL-2.0-or-later
 */
class SubEntityTypesMapper {

    /**
     * @var string[][] map of top level entity types to their sub entity types
     */
    private $typeMap;

    public function __construct( array $typeMap ) {
        $this->typeMap = $typeMap;
    }

    /**
     * Returns the parent entity type for a sub entity type, or null if given an unknown type or not a sub entity type.
     */
    public function getParentEntityType( string $type ): ?string {
        foreach ( $this->typeMap as $topLevelType => $subEntityTypes ) {
            if ( in_array( $type, $subEntityTypes ) ) {
                return $topLevelType;
            }
        }

        return null;
    }

    public function getSubEntityTypes( string $type ): array {
        return $this->typeMap[$type] ?? [];
    }

}