<?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);
 *
 */

namespace oat\taoQtiTest\models\creator;

use oat\generis\model\OntologyAwareTrait;
use oat\oatbox\service\ConfigurableService;
use oat\tao\model\resources\ResourceService;

/**
 * This service let's you access the test creator's items
 *
 * @author Bertrand Chevrier <bertrand@taotesting.com>
 */
class CreatorItems extends ConfigurableService
{
    use OntologyAwareTrait;

    const SERVICE_ID = 'taoQtiTest/CreatorItems';

    const ITEM_ROOT_CLASS_URI       = 'http://www.tao.lu/Ontologies/TAOItem.rdf#Item';
    const PROPERTY_ITEM_CONTENT_URI = 'http://www.tao.lu/Ontologies/TAOItem.rdf#ItemContent';
    const PROPERTY_ITEM_MODEL_URI   = 'http://www.tao.lu/Ontologies/TAOItem.rdf#ItemModel';
    const ITEM_MODEL_QTI_URI        = 'http://www.tao.lu/Ontologies/TAOItem.rdf#QTI';
    const LABEL_URI                 = 'http://www.w3.org/2000/01/rdf-schema#label';

    const ITEM_MODEL_SEARCH_OPTION  = 'itemModel';
    const ITEM_CONTENT_SEARCH_OPTION = 'itemContent';

    /**
     * The different lookup formats
     */
    private static $formats = ['list', 'tree'];

    /**
     * Get the list of items classes
     * @return array the classes hierarchy
     */
    public function getItemClasses()
    {
        $itemClass = $this->getClass(self::ITEM_ROOT_CLASS_URI);
        return $this->getResourceService()->getAllClasses($itemClass);
    }

    /**
     * Retrieve QTI Items for the given parameters
     * @param \core_kernel_classes_Class $itemClass the item class
     * @param string $format the lookup format
     * @param string|array  $search to filter by label if a string or provides the search filters
     * @param int $offset for paging
     * @param int $limit  for paging
     * @return array the items
     */
    public function getQtiItems(\core_kernel_classes_Class $itemClass, $format = 'list', $search = '', $offset = 0, $limit = 30)
    {
        $propertyFilters = [];

        if ($this->hasOption(self::ITEM_MODEL_SEARCH_OPTION) && $this->getOption(self::ITEM_MODEL_SEARCH_OPTION) !== false) {
            $propertyFilters[self::PROPERTY_ITEM_MODEL_URI] = $this->getOption(self::ITEM_MODEL_SEARCH_OPTION);
        }

        if ($this->hasOption(self::ITEM_CONTENT_SEARCH_OPTION) && $this->getOption(self::ITEM_MODEL_SEARCH_OPTION) !== false) {
            $propertyFilters[self::PROPERTY_ITEM_CONTENT_URI] = '*';
        }

        if (is_string($search) && strlen(trim($search)) > 0) {
            $propertyFilters[self::LABEL_URI] = $search;
        }
        if (is_array($search)) {
            foreach ($search as $uri => $value) {
                if (
                    is_string($uri) &&
                    (is_string($value) && strlen(trim($value)) > 0) ||
                    (is_array($value) && count($value) > 0)
                ) {
                    $propertyFilters[$uri] = $value;
                }
            }
        }

        $result = [];

        //whitelisting's mandatory to prevent hijacking the dependency injection
        if (in_array($format, self::$formats)) {
            //load the lookup dynamically using the format
            $itemLookup = $this->getServiceLocator()->get(self::SERVICE_ID . '/' . $format);
            if (!is_null($itemLookup) && $itemLookup instanceof ItemLookup) {
                $result = $itemLookup->getItems($itemClass, $propertyFilters, $offset, $limit);
            }
        }
        return $result;
    }

    protected function getResourceService()
    {
        return $this->getServiceLocator()->get(ResourceService::SERVICE_ID);
    }
}