Proyectos de Subversion Moodle

<?php

// This file is part of Moodle - http://moodle.org/

//

// Moodle 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, either version 3 of the License, or

// (at your option) any later version.

//

// Moodle 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 Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**

 * This file contains a class definition for the LineItem resource

 *

 * @package    ltiservice_gradebookservices

 * @copyright  2017 Cengage Learning http://www.cengage.com

 * @author     Dirk Singels, Diego del Blanco, Claude Vervoort

 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

namespace ltiservice_gradebookservices\local\resources;

use ltiservice_gradebookservices\local\service\gradebookservices;

use mod_lti\local\ltiservice\resource_base;

defined('MOODLE_INTERNAL') || die();

/**

 * A resource implementing LineItem.

 *

 * @package    ltiservice_gradebookservices

 * @copyright  2017 Cengage Learning http://www.cengage.com

 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

class lineitem extends resource_base {

    /**

     * Class constructor.

     *

     * @param gradebookservices $service Service instance

     */

    public function __construct($service) {

        parent::__construct($service);

        $this->id = 'LineItem.item';

        $this->template = '/{context_id}/lineitems/{item_id}/lineitem';

        $this->variables[] = 'LineItem.url';

        $this->formats[] = 'application/vnd.ims.lis.v2.lineitem+json';

        $this->methods[] = self::HTTP_GET;

        $this->methods[] = self::HTTP_PUT;

        $this->methods[] = self::HTTP_DELETE;

    }

    /**

     * Execute the request for this resource.

     *

     * @param \mod_lti\local\ltiservice\response $response  Response object for this request.

     */

    public function execute($response) {

        global $CFG, $DB;

        $params = $this->parse_template();

        $contextid = $params['context_id'];

        $itemid = $params['item_id'];

        $isget = $response->get_request_method() === self::HTTP_GET;

        // We will receive typeid when working with LTI 1.x, if not then we are in LTI 2.

        $typeid = optional_param('type_id', null, PARAM_INT);

        $scopes = array(gradebookservices::SCOPE_GRADEBOOKSERVICES_LINEITEM);

        if ($response->get_request_method() === self::HTTP_GET) {

            $scopes[] = gradebookservices::SCOPE_GRADEBOOKSERVICES_LINEITEM_READ;

        }

        try {

            if (!$this->check_tool($typeid, $response->get_request_data(), $scopes)) {

                throw new \Exception(null, 401);

            }

            $typeid = $this->get_service()->get_type()->id;

            if (!($course = $DB->get_record('course', array('id' => $contextid), 'id', IGNORE_MISSING))) {

                throw new \Exception("Not Found: Course {$contextid} doesn't exist", 404);

            }

            if (!$this->get_service()->is_allowed_in_context($typeid, $course->id)) {

                throw new \Exception('Not allowed in context', 403);

            }

            if (!$DB->record_exists('grade_items', array('id' => $itemid))) {

                throw new \Exception("Not Found: Grade item {$itemid} doesn't exist", 404);

            }

            $item = $this->get_service()->get_lineitem($contextid, $itemid, $typeid);

            if ($item === false) {

                throw new \Exception('Line item does not exist', 404);

            }

            require_once($CFG->libdir.'/gradelib.php');

            switch ($response->get_request_method()) {

                case self::HTTP_GET:

                    $this->get_request($response, $item, $typeid);

                    break;

                case self::HTTP_PUT:

                    $json = $this->process_put_request($response->get_request_data(), $item, $typeid);

                    $response->set_body($json);

                    $response->set_code(200);

                    break;

                case self::HTTP_DELETE:

                    $this->process_delete_request($item);

                    $response->set_code(204);

                    break;

            }

        } catch (\Exception $e) {

            $response->set_code($e->getCode());

            $response->set_reason($e->getMessage());

        }

    }

    /**

     * Process a GET request.

     *

     * @param \mod_lti\local\ltiservice\response $response Response object for this request.

     * @param object $item Grade item instance.

     * @param string $typeid Tool Type Id

     */

    private function get_request($response, $item, $typeid) {

        $response->set_content_type($this->formats[0]);

        $lineitem = gradebookservices::item_for_json($item, substr(parent::get_endpoint(),

            0, strrpos(parent::get_endpoint(), "/", -10)), $typeid);

        $response->set_body(json_encode($lineitem));

    }

    /**

     * Process a PUT request.

     *

     * @param string $body PUT body

     * @param \ltiservice_gradebookservices\local\resources\lineitem $olditem Grade item instance

     * @param string $typeid Tool Type Id

     *

     * @return string

     * @throws \Exception

     */

    private function process_put_request($body, $olditem, $typeid) {

        global $DB;

        $json = json_decode($body);

        if (empty($json) ||

                !isset($json->scoreMaximum) ||

                !isset($json->label)) {

            throw new \Exception(null, 400);

        }

        $item = \grade_item::fetch(array('id' => $olditem->id, 'courseid' => $olditem->courseid));

        $gbs = gradebookservices::find_ltiservice_gradebookservice_for_lineitem($olditem->id);

        $updategradeitem = false;

        $rescalegrades = false;

        $oldgrademax = grade_floatval($item->grademax);

        $upgradegradebookservices = false;

        if ($item->itemname !== $json->label) {

            $updategradeitem = true;

        }

        $item->itemname = $json->label;

        if (!is_numeric($json->scoreMaximum)) {

            throw new \Exception(null, 400);

        } else {

            if (grade_floats_different($oldgrademax,

                    grade_floatval($json->scoreMaximum))) {

                $updategradeitem = true;

                $rescalegrades = true;

            }

            $item->grademax = grade_floatval($json->scoreMaximum);

        }

        if ($gbs) {

            $resourceid = (isset($json->resourceId)) ? $json->resourceId : '';

            $tag = (isset($json->tag)) ? $json->tag : '';

            if ($gbs->tag !== $tag || $gbs->resourceid !== $resourceid) {

                $upgradegradebookservices = true;

            }

            $gbs->tag = $tag;

            $gbs->resourceid = $resourceid;

            $incomingurl = null;

            $incomingparams = null;

            if (isset($json->submissionReview)) {

                $incomingurl = $json->submissionReview->url ?? 'DEFAULT';

                if (isset($json->submissionReview->custom)) {

                    $incomingparams = params_to_string($json->submissionReview->custom);

                }

            }

            if ($gbs->subreviewurl ?? null !== $incomingurl || $gbs->subreviewparams ?? null !== $incomingparams) {

                $upgradegradebookservices = true;

                $gbs->subreviewurl = $incomingurl;

                $gbs->subreviewparams = $incomingparams;

            }

        }

        $ltilinkid = null;

        if (isset($json->resourceLinkId)) {

            if (is_numeric($json->resourceLinkId)) {

                $ltilinkid = $json->resourceLinkId;

                if ($gbs) {

                    if (intval($gbs->ltilinkid) !== intval($json->resourceLinkId)) {

                        $gbs->ltilinkid = $json->resourceLinkId;

                        $upgradegradebookservices = true;

                    }

                } else {

                    if (intval($item->iteminstance) !== intval($json->resourceLinkId)) {

                        $item->iteminstance = intval($json->resourceLinkId);

                        $updategradeitem = true;

                    }

                }

            } else {

                throw new \Exception(null, 400);

            }

        } else if (isset($json->ltiLinkId)) {

            if (is_numeric($json->ltiLinkId)) {

                $ltilinkid = $json->ltiLinkId;

                if ($gbs) {

                    if (intval($gbs->ltilinkid) !== intval($json->ltiLinkId)) {

                        $gbs->ltilinkid = $json->ltiLinkId;

                        $upgradegradebookservices = true;

                    }

                } else {

                    if (intval($item->iteminstance) !== intval($json->ltiLinkId)) {

                        $item->iteminstance = intval($json->ltiLinkId);

                        $updategradeitem = true;

                    }

                }

            } else {

                throw new \Exception(null, 400);

            }

        }

        if ($ltilinkid != null) {

            if (is_null($typeid)) {

                if (!gradebookservices::check_lti_id($ltilinkid, $item->courseid,

                        $this->get_service()->get_tool_proxy()->id)) {

                            throw new \Exception(null, 403);

                }

            } else {

                if (!gradebookservices::check_lti_1x_id($ltilinkid, $item->courseid,

                        $typeid)) {

                            throw new \Exception(null, 403);

                }

            }

        }

        if ($updategradeitem) {

            if (!$item->update('mod/ltiservice_gradebookservices')) {

                throw new \Exception(null, 500);

            }

            if ($rescalegrades) {

                $item->rescale_grades_keep_percentage(0, $oldgrademax, 0, $item->grademax);

            }

        }

        $lineitem = new lineitem($this->get_service());

        $endpoint = $lineitem->get_endpoint();

        if ($upgradegradebookservices) {

            if (is_null($typeid)) {

                $toolproxyid = $this->get_service()->get_tool_proxy()->id;

                $baseurl = null;

            } else {

                $toolproxyid = null;

                $baseurl = lti_get_type_type_config($typeid)->lti_toolurl;

            }

            $DB->update_record('ltiservice_gradebookservices', (object)array(

                    'id' => $gbs->id,

                    'gradeitemid' => $gbs->gradeitemid,

                    'courseid' => $gbs->courseid,

                    'toolproxyid' => $toolproxyid,

                    'typeid' => $typeid,

                    'baseurl' => $baseurl,

                    'ltilinkid' => $ltilinkid,

                    'resourceid' => $resourceid,

                    'tag' => $gbs->tag,

                    'subreviewurl' => $gbs->subreviewurl,

                    'subreviewparams' => $gbs->subreviewparams

            ));

        }

        if (is_null($typeid)) {

            $id = "{$endpoint}";

            $json->id = $id;

        } else {

            $id = "{$endpoint}?type_id={$typeid}";

            $json->id = $id;

        }

        return json_encode($json, JSON_UNESCAPED_SLASHES);

    }

    /**

     * Process a DELETE request.

     *

     * @param \ltiservice_gradebookservices\local\resources\lineitem $item Grade item instance

     * @throws \Exception

     */

    private function process_delete_request($item) {

        global $DB;

        $gradeitem = \grade_item::fetch(array('id' => $item->id));

        if (($gbs = gradebookservices::find_ltiservice_gradebookservice_for_lineitem($item->id)) == false) {

            throw new \Exception(null, 403);

        }

        if (!$gradeitem->delete('mod/ltiservice_gradebookservices')) {

            throw new \Exception(null, 500);

        } else {

            $sqlparams = array();

            $sqlparams['id'] = $gbs->id;

            if (!$DB->delete_records('ltiservice_gradebookservices', $sqlparams)) {

                throw new \Exception(null, 500);

            }

        }

    }

    /**

     * Parse a value for custom parameter substitution variables.

     *

     * @param string $value String to be parsed

     *

     * @return string

     */

    public function parse_value($value) {

        global $COURSE, $CFG;

        if (strpos($value, '$LineItem.url') !== false) {

            $resolved = '';

            require_once($CFG->libdir . '/gradelib.php');

            $this->params['context_id'] = $COURSE->id;

            if ($tool = $this->get_service()->get_type()) {

                $this->params['tool_code'] = $tool->id;

            }

            $id = optional_param('id', 0, PARAM_INT); // Course Module ID.

            if (empty($id)) {

                $hint = optional_param('lti_message_hint', "", PARAM_TEXT);

                if ($hint) {

                    $hintdec = json_decode($hint);

                    if (isset($hintdec->cmid)) {

                        $id = $hintdec->cmid;

                    }

                }

            }

            if (!empty($id)) {

                $cm = get_coursemodule_from_id('lti', $id, 0, false, MUST_EXIST);

                $id = $cm->instance;

                $item = grade_get_grades($COURSE->id, 'mod', 'lti', $id);

                if ($item && $item->items) {

                    $this->params['item_id'] = $item->items[0]->id;

                    $resolved = parent::get_endpoint();

                    $resolved .= "?type_id={$tool->id}";

                }

            }

            $value = str_replace('$LineItem.url', $resolved, $value);

        }

        return $value;

    }

}