wikimedia/mediawiki-extensions-Wikibase

<?php

declare( strict_types = 1 );

namespace Wikibase\DataAccess;

use Wikibase\DataModel\Entity\EntityId;
use Wikibase\Lib\Store\EntityRevisionLookup;
use Wikibase\Lib\Store\LatestRevisionIdResult;
use Wikibase\Lib\Store\LookupConstants;
use Wikimedia\Assert\Assert;

/**
 * An EntityRevisionLookup that dispatches by entity type to inner EntityRevisionLookups.
 * If no lookup is registered for the entity type the lookup will fail in an unexceptional
 * way.
 *
 * TODO Wikibase\Lib\Store\TypeDispatchingEntityRevisionLookup is similar, but a bit different,
 * also conceptually. The other class could maybe be renamed or so?
 *
 * TODO this has been introduced into data-access with a couple of points that still bind to
 * wikibase lib and other parts of mediawiki, these should be cleaned up:
 *  - Wikibase\Lib\Store\EntityRevisionLookup;
 *   - Wikibase\Lib\Store\RevisionedUnresolvedRedirectException
 *   - Wikibase\Lib\Store\StorageException
 *    - Status
 *  - Wikibase\Lib\Store\LatestRevisionIdResult;
 *
 * @license GPL-2.0-or-later
 */
class ByTypeDispatchingEntityRevisionLookup implements EntityRevisionLookup {

    /** @var EntityRevisionLookup[] */
    private $lookups;

    public function __construct( array $lookups ) {
        Assert::parameterElementType( EntityRevisionLookup::class, $lookups, '$lookups' );
        Assert::parameterElementType( 'string', array_keys( $lookups ), 'keys of $lookups' );

        $this->lookups = $lookups;
    }

    public function getEntityRevision(
        EntityId $entityId,
        $revisionId = 0,
        $mode = LookupConstants::LATEST_FROM_REPLICA
    ) {
        $lookup = $this->getLookupForEntity( $entityId );

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

        return $lookup->getEntityRevision( $entityId, $revisionId, $mode );
    }

    public function getLatestRevisionId( EntityId $entityId, $mode = LookupConstants::LATEST_FROM_REPLICA ) {
        $lookup = $this->getLookupForEntity( $entityId );

        if ( $lookup === null ) {
            return LatestRevisionIdResult::nonexistentEntity();
        }

        return $lookup->getLatestRevisionId( $entityId, $mode );
    }

    private function getLookupForEntity( EntityId $entityId ): ?EntityRevisionLookup {
        $entityType = $entityId->getEntityType();
        if ( !array_key_exists( $entityType, $this->lookups ) ) {
            return null;
        }

        return $this->lookups[$entityType];
    }

}