wikimedia/mediawiki-extensions-Wikibase

<?php

declare( strict_types = 1 );
namespace Wikibase\Repo\FederatedProperties;

/**
 * A class for getting namespaces for federated properties one time per request.
 * @license GPL-2.0-or-later
 */
class ApiEntityNamespaceInfoLookup {

    /**
     * @var array[]
     */
    private $namespaces;

    /**
     * @var GenericActionApiClient
     */
    private $api;

    /**
     * @var array
     */
    private $contentModelMapping;

    public function __construct( GenericActionApiClient $api, array $contentModelMapping ) {
        $this->api = $api;
        $this->contentModelMapping = $contentModelMapping;
    }

    /**
     * @param string $entityType
     * @return string|null Namespace name or null if no namespace is found for the entity
     */
    public function getNamespaceNameForEntityType( string $entityType ): ?string {
        if ( !array_key_exists( $entityType, $this->contentModelMapping ) ) {
            return null;
        }

        $entityContentModel = $this->contentModelMapping[$entityType];
        $this->fetchNamespaces();

        return $this->getNamespaceNameForContentModel( $entityContentModel );
    }

    private function fetchNamespaces() {
        if ( $this->namespaces ) {
            return;
        }

        // @phan-suppress-next-line PhanTypeArraySuspiciousNullable The API response will be JSON here
        $this->namespaces = json_decode( $this->api->get( [
            'action' => 'query',
            'meta' => 'siteinfo',
            'siprop' => 'namespaces',
            'format' => 'json',
        ] )->getBody()->getContents(), true )['query']['namespaces'];
    }

    private function getNamespaceNameForContentModel( string $entityContentModel ): ?string {
        foreach ( $this->namespaces as $namespace ) {
            if ( isset( $namespace['defaultcontentmodel'] ) && $namespace['defaultcontentmodel'] === $entityContentModel ) {
                if ( array_key_exists( 'canonical', $namespace ) ) {
                    return $namespace['canonical'];
                }
                if ( $namespace['id'] === NS_MAIN ) {
                    return '';
                }
            }
        }

        return null;
    }

}