<?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) 2013 (original work) Open Assessment Technologies SA (under the project TAO-PRODUCT);
 *
 *
 */

use oat\generis\model\OntologyRdf;
use oat\generis\model\OntologyRdfs;
use oat\oatbox\event\EventManagerAwareTrait;
use oat\tao\model\event\RdfImportEvent;
use oat\tao\model\import\ImportHandlerHelperTrait;
use oat\tao\model\import\TaskParameterProviderInterface;
use Zend\ServiceManager\ServiceLocatorAwareInterface;

/**
 * RDF Import Handler
 *
 * @access  public
 * @author  Joel Bout, <joel@taotesting.com>
 * @package tao
 */
class tao_models_classes_import_RdfImporter implements tao_models_classes_import_ImportHandler, ServiceLocatorAwareInterface, TaskParameterProviderInterface
{
    use EventManagerAwareTrait;
    use ImportHandlerHelperTrait;

    /**
     * (non-PHPdoc)
     * @see tao_models_classes_import_ImportHandler::getLabel()
     */
    public function getLabel()
    {
        return __('RDF');
    }

    /**
     * (non-PHPdoc)
     * @see tao_models_classes_import_ImportHandler::getForm()
     */
    public function getForm()
    {
        $form = new tao_models_classes_import_RdfImportForm();

        return $form->getForm();
    }

    /**
     * @param core_kernel_classes_Class $class
     * @param tao_helpers_form_Form|array $form
     * @param string|null $userId owner of the resource
     * @return common_report_Report
     * @throws common_Exception
     * @throws common_exception_Error
     */
    public function import($class, $form, $userId = null)
    {
        $parser = new tao_models_classes_Parser($this->fetchUploadedFile($form), ['extension' => 'rdf']);
        $parser->validate();

        if (!$parser->isValid()) {
            $report = common_report_Report::createFailure(__('Nothing imported'));
            $report->add($parser->getReport());
        } else {
            $report = $this->flatImport($parser->getContent(), $class);

            if (!$report->containsError()) {
                $this->getUploadService()->remove($parser->getSource());
            }

            if ($report->getType() == common_report_Report::TYPE_SUCCESS) {
                $this->getEventManager()->trigger(new RdfImportEvent($report));
            }
        }

        return $report;
    }

    /**
     * Imports the rdf file into the selected class
     *
     * @param string                    $content
     * @param core_kernel_classes_Class $class
     * @return common_report_Report
     */
    protected function flatImport($content, core_kernel_classes_Class $class)
    {
        $report = common_report_Report::createSuccess(__('Data imported successfully'));

        $graph = new EasyRdf_Graph();
        $graph->parse($content);

        // keep type property
        $map = [
            OntologyRdf::RDF_PROPERTY => OntologyRdf::RDF_PROPERTY
        ];

        foreach ($graph->resources() as $resource) {
            $map[$resource->getUri()] = common_Utils::getNewUri();
        }

        $format = EasyRdf_Format::getFormat('php');
        $data = $graph->serialise($format);

        foreach ($data as $subjectUri => $propertiesValues) {
            $resource = new core_kernel_classes_Resource($map[$subjectUri]);
            $subreport = $this->importProperties($resource, $propertiesValues, $map, $class);
            $report->add($subreport);
        }

        return $report;
    }

    /**
     * Import the properties of the resource
     *
     * @param core_kernel_classes_Resource $resource
     * @param array                        $propertiesValues
     * @param array                        $map
     * @param core_kernel_classes_Class    $class
     * @return common_report_Report
     */
    protected function importProperties(core_kernel_classes_Resource $resource, $propertiesValues, $map, $class)
    {
        if (isset($propertiesValues[OntologyRdf::RDF_TYPE])) {
            // assuming single Type
            if (count($propertiesValues[OntologyRdf::RDF_TYPE]) > 1) {
                return new common_report_Report(common_report_Report::TYPE_ERROR, __('Resource not imported due to multiple types'));
            } else {
                foreach ($propertiesValues[OntologyRdf::RDF_TYPE] as $k => $v) {
                    $classType = isset($map[$v['value']])
                        ? new core_kernel_classes_Class($map[$v['value']])
                        : $class;
                    //$resource->setType($classType);
                    $classType->createInstance(null, null, $resource->getUri());
                }
            }
            unset($propertiesValues[OntologyRdf::RDF_TYPE]);
        }

        if (isset($propertiesValues[OntologyRdfs::RDFS_SUBCLASSOF])) {
            $resource = new core_kernel_classes_Class($resource);
            // assuming single subclass
            if (isset($propertiesValues[OntologyRdf::RDF_TYPE]) && count($propertiesValues[OntologyRdf::RDF_TYPE]) > 1) {
                return new common_report_Report(common_report_Report::TYPE_ERROR, __('Resource not imported due to multiple super classes'));
            }
            foreach ($propertiesValues[OntologyRdfs::RDFS_SUBCLASSOF] as $k => $v) {
                $classSup = isset($map[$v['value']])
                    ? new core_kernel_classes_Class($map[$v['value']])
                    : $class;
                $resource->setSubClassOf($classSup);
            }

            unset($propertiesValues[OntologyRdfs::RDFS_SUBCLASSOF]);
        }
        foreach ($propertiesValues as $prop => $values) {
            $property = new core_kernel_classes_Property(isset($map[$prop]) ? $map[$prop] : $prop);
            foreach ($values as $k => $v) {
                $value = isset($map[$v['value']]) ? $map[$v['value']] : $v['value'];
                if (isset($v['lang'])) {
                    $resource->setPropertyValueByLg($property, $value, $v['lang']);
                } else {
                    $resource->setPropertyValue($property, $value);
                }
            }
        }
        $msg = $resource instanceof core_kernel_classes_Class
            ? __('Successfully imported class "%s"', $resource->getLabel())
            : __('Successfully imported "%s"', $resource->getLabel());

        return new common_report_Report(common_report_Report::TYPE_SUCCESS, $msg, $resource);
    }
}