owncloud/core

<?php
/**
 * @author Viktar Dubiniuk <dubiniuk@owncloud.com>
 *
 * @copyright Copyright (c) 2018, ownCloud GmbH
 * @license AGPL-3.0
 *
 * This code is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License, version 3,
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License, version 3,
 * along with this program.  If not, see <http://www.gnu.org/licenses/>
 *
 */

namespace OCA\FederatedFileSharing\Ocm;

use OCP\Constants;

/**
 * Class Permissions
 *
 * @package OCA\FederatedFileSharing\Ocm
 */
class Permissions {
    public const OCM_PERMISSION_READ = 'read';
    public const OCM_PERMISSION_WRITE = 'write';
    public const OCM_PERMISSION_SHARE = 'share';

    /**
     * Maps numeric permissions to an array of string permissions
     *
     * @param int $ocPermissions
     *
     * @return array
     */
    public static function toOcmPermissions(int $ocPermissions): array {
        $ocPermissions = (int) $ocPermissions;
        $ocmPermissions = [];
        if ($ocPermissions & Constants::PERMISSION_READ) {
            $ocmPermissions[] = self::OCM_PERMISSION_READ;
        }
        if (($ocPermissions & Constants::PERMISSION_CREATE)
            || ($ocPermissions & Constants::PERMISSION_UPDATE)
        ) {
            $ocmPermissions[] = self::OCM_PERMISSION_WRITE;
        }
        if ($ocPermissions & Constants::PERMISSION_SHARE) {
            $ocmPermissions[] = self::OCM_PERMISSION_SHARE;
        }
        return $ocmPermissions;
    }

    /**
     * @param string[] $ocmPermissions
     *
     * @return int
     */
    public static function toOcPermissions(array $ocmPermissions): int {
        $permissionMap = [
            self::OCM_PERMISSION_READ => Constants::PERMISSION_READ,
            self::OCM_PERMISSION_WRITE => Constants::PERMISSION_CREATE + Constants::PERMISSION_UPDATE,
            self::OCM_PERMISSION_SHARE => Constants::PERMISSION_SHARE
        ];
        $ocPermissions = 0;
        foreach ($ocmPermissions as $ocmPermission) {
            if (isset($permissionMap[$ocmPermission])) {
                $ocPermissions += $permissionMap[$ocmPermission];
            }
        }

        return $ocPermissions;
    }

    public static function isNewPermissionHigher(int $existingPermission, int $newPermission): bool {
        return ($existingPermission | $newPermission) !== $existingPermission;
    }
}