<?php

/**
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; under version 2
 * of the License (non-upgradable).
 *
 * 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * Copyright (c) 2017 (original work) Open Assessment Technologies SA (under the project TAO-PRODUCT);
 *
 *
 */

use oat\generis\model\GenerisRdf;
use oat\oatbox\user\User;
use oat\oatbox\Refreshable;

/**
 * Abstract User
 *
 * @access public
 * @author Joel Bout, <joel@taotesting.com>
 * @package generis
 */
abstract class common_user_User implements User, Refreshable
{
    /**
     * Store roles to prevent recalculation in runtime
     * @var array
     */
    protected $roles = [];

    abstract public function getIdentifier();
    
    abstract public function getPropertyValues($property);

    abstract public function refresh();

    /**
     * Extends the users explizit roles with the implizit rules
     * of the local system
     *
     * @return array the identifiers of the roles:
     */
    public function getRoles()
    {
        $returnValue = [];
        if (! $this->roles) {
            // We use a Depth First Search approach to flatten the Roles Graph.
            foreach ($this->getPropertyValues(GenerisRdf::PROPERTY_USER_ROLES) as $roleUri) {
                $returnValue[] = $roleUri;
                foreach (core_kernel_users_Service::singleton()->getIncludedRoles(new core_kernel_classes_Resource($roleUri)) as $role) {
                    $returnValue[] = $role->getUri();
                }
            }
            $returnValue = array_unique($returnValue);
            $this->roles = $returnValue;
        }
        return $this->roles;
    }
}