Eloy Lafuente (stronk7)
d9f7fe9c3f
@const is not a valid phpdoc tag and @var should be used to document both classes properties and constants (no matter how weird that may sound, heh). Link to (draft right now) PHP-FIG: https://github.com/php-fig/fig-standards/blob/master/proposed/phpdoc-tags.md#518-var So, with this commit we are just replacing all uses by the correct @var one. Note that the type is entirely optional, in fact I think that there isn't much need of it for constants because it's obvious for both humans and machines which the type is. But, as far as it's also correct to specify it, we haven't modified that detail. The only detail modified are the cases where the constant name was specified in the phpdoc, that's not needed, hence, the names have been removed from there when present (a couple of cases).
596 lines
23 KiB
PHP
596 lines
23 KiB
PHP
<?php
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// This file is part of Moodle - http://moodle.org/
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//
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// Moodle is free software: you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// Moodle is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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//
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// You should have received a copy of the GNU General Public License
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// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
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/**
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* This file defines a class with accumulative grading strategy logic
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*
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* @package workshopform_accumulative
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* @copyright 2009 David Mudrak <david.mudrak@gmail.com>
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* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
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*/
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defined('MOODLE_INTERNAL') || die();
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require_once(__DIR__ . '/../lib.php'); // interface definition
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require_once($CFG->libdir . '/gradelib.php'); // to handle float vs decimal issues
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/**
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* Server workshop files
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*
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* @category files
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* @param stdClass $course course object
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* @param stdClass $cm course module object
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* @param stdClass $context context object
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* @param string $filearea file area
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* @param array $args extra arguments
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* @param bool $forcedownload whether or not force download
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* @param array $options additional options affecting the file serving
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* @return bool
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*/
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function workshopform_accumulative_pluginfile($course, $cm, $context, $filearea, array $args, $forcedownload, array $options=array()) {
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global $DB;
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if ($context->contextlevel != CONTEXT_MODULE) {
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return false;
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}
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require_login($course, true, $cm);
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if ($filearea !== 'description') {
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return false;
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}
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$itemid = (int)array_shift($args); // the id of the assessment form dimension
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if (!$workshop = $DB->get_record('workshop', array('id' => $cm->instance))) {
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send_file_not_found();
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}
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if (!$dimension = $DB->get_record('workshopform_accumulative', array('id' => $itemid ,'workshopid' => $workshop->id))) {
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send_file_not_found();
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}
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// TODO now make sure the user is allowed to see the file
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// (media embedded into the dimension description)
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$fs = get_file_storage();
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$relativepath = implode('/', $args);
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$fullpath = "/$context->id/workshopform_accumulative/$filearea/$itemid/$relativepath";
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if (!$file = $fs->get_file_by_hash(sha1($fullpath)) or $file->is_directory()) {
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return false;
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}
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// finally send the file
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send_stored_file($file, 0, 0, $forcedownload, $options);
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}
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/**
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* Accumulative grading strategy logic.
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*/
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class workshop_accumulative_strategy implements workshop_strategy {
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/** @var default number of dimensions to show */
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const MINDIMS = 3;
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/** @var number of dimensions to add */
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const ADDDIMS = 2;
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/** @var workshop the parent workshop instance */
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protected $workshop;
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/** @var array definition of the assessment form fields */
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protected $dimensions = null;
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/** @var array options for dimension description fields */
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protected $descriptionopts;
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/**
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* Constructor
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*
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* @param workshop $workshop The workshop instance record
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* @return void
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*/
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public function __construct(workshop $workshop) {
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$this->workshop = $workshop;
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$this->dimensions = $this->load_fields();
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$this->descriptionopts = array('trusttext' => true, 'subdirs' => false, 'maxfiles' => -1);
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}
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/**
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* Factory method returning an instance of an assessment form editor class
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*
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* @param $actionurl URL of form handler, defaults to auto detect the current url
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*/
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public function get_edit_strategy_form($actionurl=null) {
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global $CFG; // needed because the included files use it
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global $PAGE;
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require_once(__DIR__ . '/edit_form.php');
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$fields = $this->prepare_form_fields($this->dimensions);
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$nodimensions = count($this->dimensions);
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$norepeatsdefault = max($nodimensions + self::ADDDIMS, self::MINDIMS);
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$norepeats = optional_param('norepeats', $norepeatsdefault, PARAM_INT); // number of dimensions
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$noadddims = optional_param('noadddims', '', PARAM_ALPHA); // shall we add more?
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if ($noadddims) {
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$norepeats += self::ADDDIMS;
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}
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// Append editor context to editor options, giving preference to existing context.
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$this->descriptionopts = array_merge(array('context' => $PAGE->context), $this->descriptionopts);
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// prepare the embeded files
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for ($i = 0; $i < $nodimensions; $i++) {
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// prepare all editor elements
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$fields = file_prepare_standard_editor($fields, 'description__idx_'.$i, $this->descriptionopts,
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$PAGE->context, 'workshopform_accumulative', 'description', $fields->{'dimensionid__idx_'.$i});
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}
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$customdata = array();
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$customdata['workshop'] = $this->workshop;
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$customdata['strategy'] = $this;
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$customdata['norepeats'] = $norepeats;
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$customdata['descriptionopts'] = $this->descriptionopts;
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$customdata['current'] = $fields;
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$attributes = array('class' => 'editstrategyform');
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return new workshop_edit_accumulative_strategy_form($actionurl, $customdata, 'post', '', $attributes);
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}
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/**
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* Save the assessment dimensions into database
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*
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* Saves data into the main strategy form table. If the record->id is null or zero,
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* new record is created. If the record->id is not empty, the existing record is updated. Records with
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* empty 'description' field are removed from database.
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* The passed data object are the raw data returned by the get_data().
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*
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* @uses $DB
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* @param stdClass $data Raw data returned by the dimension editor form
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* @return void
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*/
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public function save_edit_strategy_form(stdclass $data) {
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global $DB, $PAGE;
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$workshopid = $data->workshopid;
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$norepeats = $data->norepeats;
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$data = $this->prepare_database_fields($data);
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$records = $data->accumulative; // records to be saved into {workshopform_accumulative}
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$todelete = array(); // dimension ids to be deleted
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for ($i=0; $i < $norepeats; $i++) {
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$record = $records[$i];
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if (0 == strlen(trim($record->description_editor['text']))) {
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if (!empty($record->id)) {
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// existing record with empty description - to be deleted
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$todelete[] = $record->id;
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}
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continue;
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}
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if (empty($record->id)) {
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// new field
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$record->id = $DB->insert_record('workshopform_accumulative', $record);
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} else {
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// exiting field
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$DB->update_record('workshopform_accumulative', $record);
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}
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// re-save with correct path to embeded media files
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$record = file_postupdate_standard_editor($record, 'description', $this->descriptionopts,
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$PAGE->context, 'workshopform_accumulative', 'description', $record->id);
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$DB->update_record('workshopform_accumulative', $record);
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}
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$this->delete_dimensions($todelete);
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}
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/**
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* Factory method returning an instance of an assessment form
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*
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* @param moodle_url $actionurl URL of form handler, defaults to auto detect the current url
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* @param string $mode Mode to open the form in: preview/assessment
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* @param stdClass $assessment The current assessment
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* @param bool $editable
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* @param array $options
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*/
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public function get_assessment_form(moodle_url $actionurl=null, $mode='preview', stdclass $assessment=null, $editable=true, $options=array()) {
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global $CFG; // needed because the included files use it
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global $PAGE;
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global $DB;
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require_once(__DIR__ . '/assessment_form.php');
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$fields = $this->prepare_form_fields($this->dimensions);
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$nodimensions = count($this->dimensions);
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// rewrite URLs to the embeded files
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for ($i = 0; $i < $nodimensions; $i++) {
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$fields->{'description__idx_'.$i} = file_rewrite_pluginfile_urls($fields->{'description__idx_'.$i},
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'pluginfile.php', $PAGE->context->id, 'workshopform_accumulative', 'description', $fields->{'dimensionid__idx_'.$i});
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}
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if ('assessment' === $mode and !empty($assessment)) {
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// load the previously saved assessment data
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$grades = $this->get_current_assessment_data($assessment);
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$current = new stdclass();
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for ($i = 0; $i < $nodimensions; $i++) {
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$dimid = $fields->{'dimensionid__idx_'.$i};
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if (isset($grades[$dimid])) {
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$current->{'gradeid__idx_'.$i} = $grades[$dimid]->id;
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$current->{'grade__idx_'.$i} = $grades[$dimid]->grade;
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$current->{'peercomment__idx_'.$i} = $grades[$dimid]->peercomment;
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}
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}
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}
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// set up the required custom data common for all strategies
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$customdata['strategy'] = $this;
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$customdata['workshop'] = $this->workshop;
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$customdata['mode'] = $mode;
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$customdata['options'] = $options;
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// set up strategy-specific custom data
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$customdata['nodims'] = $nodimensions;
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$customdata['fields'] = $fields;
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$customdata['current'] = isset($current) ? $current : null;
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$attributes = array('class' => 'assessmentform accumulative');
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return new workshop_accumulative_assessment_form($actionurl, $customdata, 'post', '', $attributes, $editable);
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}
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/**
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* Saves the filled assessment
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*
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* This method processes data submitted using the form returned by {@link get_assessment_form()}
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*
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* @param stdClass $assessment Assessment being filled
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* @param stdClass $data Raw data as returned by the assessment form
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* @return float|null Raw grade (0.00000 to 100.00000) for submission as suggested by the peer
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*/
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public function save_assessment(stdclass $assessment, stdclass $data) {
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global $DB;
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if (!isset($data->nodims)) {
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throw new coding_exception('You did not send me the number of assessment dimensions to process');
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}
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for ($i = 0; $i < $data->nodims; $i++) {
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$grade = new stdclass();
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$grade->id = $data->{'gradeid__idx_' . $i};
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$grade->assessmentid = $assessment->id;
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$grade->strategy = 'accumulative';
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$grade->dimensionid = $data->{'dimensionid__idx_' . $i};
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if (isset($data->{'grade__idx_' . $i})) {
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$grade->grade = $data->{'grade__idx_' . $i};
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}
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$grade->peercomment = $data->{'peercomment__idx_' . $i};
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$grade->peercommentformat = FORMAT_MOODLE;
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if (empty($grade->id)) {
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// new grade
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$grade->id = $DB->insert_record('workshop_grades', $grade);
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} else {
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// updated grade
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$DB->update_record('workshop_grades', $grade);
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}
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}
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return $this->update_peer_grade($assessment);
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}
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/**
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* Has the assessment form been defined and is ready to be used by the reviewers?
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*
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* @return boolean
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*/
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public function form_ready() {
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if (count($this->dimensions) > 0) {
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return true;
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}
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return false;
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}
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/**
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* @see parent::get_assessments_recordset()
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*/
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public function get_assessments_recordset($restrict=null) {
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global $DB;
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$sql = 'SELECT s.id AS submissionid,
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a.id AS assessmentid, a.weight AS assessmentweight, a.reviewerid, a.gradinggrade,
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g.dimensionid, g.grade
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FROM {workshop_submissions} s
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JOIN {workshop_assessments} a ON (a.submissionid = s.id)
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JOIN {workshop_grades} g ON (g.assessmentid = a.id AND g.strategy = :strategy)
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WHERE s.example=0 AND s.workshopid=:workshopid'; // to be cont.
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$params = array('workshopid' => $this->workshop->id, 'strategy' => $this->workshop->strategy);
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if (is_null($restrict)) {
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// update all users - no more conditions
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} elseif (!empty($restrict)) {
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list($usql, $uparams) = $DB->get_in_or_equal($restrict, SQL_PARAMS_NAMED);
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$sql .= " AND a.reviewerid $usql";
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$params = array_merge($params, $uparams);
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} else {
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throw new coding_exception('Empty value is not a valid parameter here');
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}
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$sql .= ' ORDER BY s.id'; // this is important for bulk processing
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return $DB->get_recordset_sql($sql, $params);
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}
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/**
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* @see parent::get_dimensions_info()
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*/
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public function get_dimensions_info() {
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global $DB;
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$sql = 'SELECT d.id, d.grade, d.weight, s.scale
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FROM {workshopform_accumulative} d
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LEFT JOIN {scale} s ON (d.grade < 0 AND -d.grade = s.id)
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WHERE d.workshopid = :workshopid';
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$params = array('workshopid' => $this->workshop->id);
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$dimrecords = $DB->get_records_sql($sql, $params);
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$diminfo = array();
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foreach ($dimrecords as $dimid => $dimrecord) {
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$diminfo[$dimid] = new stdclass();
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$diminfo[$dimid]->id = $dimid;
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$diminfo[$dimid]->weight = $dimrecord->weight;
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if ($dimrecord->grade < 0) {
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// the dimension uses a scale
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$diminfo[$dimid]->min = 1;
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$diminfo[$dimid]->max = count(explode(',', $dimrecord->scale));
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$diminfo[$dimid]->scale = $dimrecord->scale;
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} else {
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// the dimension uses points
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$diminfo[$dimid]->min = 0;
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$diminfo[$dimid]->max = grade_floatval($dimrecord->grade);
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}
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}
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return $diminfo;
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}
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/**
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* Is a given scale used by the instance of workshop?
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*
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* @param int $scaleid id of the scale to check
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* @param int|null $workshopid id of workshop instance to check, checks all in case of null
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* @return bool
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*/
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public static function scale_used($scaleid, $workshopid=null) {
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global $DB;
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$conditions['grade'] = -$scaleid;
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if (!is_null($workshopid)) {
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$conditions['workshopid'] = $workshopid;
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}
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return $DB->record_exists('workshopform_accumulative', $conditions);
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}
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/**
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* Delete all data related to a given workshop module instance
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*
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* @see workshop_delete_instance()
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* @param int $workshopid id of the workshop module instance being deleted
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* @return void
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*/
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public static function delete_instance($workshopid) {
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global $DB;
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$DB->delete_records('workshopform_accumulative', array('workshopid' => $workshopid));
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}
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////////////////////////////////////////////////////////////////////////////////
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// Internal methods //
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////////////////////////////////////////////////////////////////////////////////
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/**
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* Loads the fields of the assessment form currently used in this workshop
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*
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* @return array definition of assessment dimensions
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*/
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protected function load_fields() {
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global $DB;
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$sql = 'SELECT *
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FROM {workshopform_accumulative}
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WHERE workshopid = :workshopid
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ORDER BY sort';
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$params = array('workshopid' => $this->workshop->id);
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return $DB->get_records_sql($sql, $params);
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}
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/**
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* Maps the dimension data from DB to the form fields
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*
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* @param array $raw Array of raw dimension records as returned by {@link load_fields()}
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* @return array Array of fields data to be used by the mform set_data
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*/
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protected function prepare_form_fields(array $raw) {
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$formdata = new stdclass();
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$key = 0;
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foreach ($raw as $dimension) {
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$formdata->{'dimensionid__idx_' . $key} = $dimension->id;
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$formdata->{'description__idx_' . $key} = $dimension->description;
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$formdata->{'description__idx_' . $key.'format'} = $dimension->descriptionformat;
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$formdata->{'grade__idx_' . $key} = $dimension->grade;
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$formdata->{'weight__idx_' . $key} = $dimension->weight;
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$key++;
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}
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return $formdata;
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}
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/**
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* Deletes dimensions and removes embedded media from its descriptions
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*
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* todo we may check that there are no assessments done using these dimensions and probably remove them
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*
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* @param array $masterids
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* @return void
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*/
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protected function delete_dimensions(array $ids) {
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global $DB, $PAGE;
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$fs = get_file_storage();
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foreach ($ids as $id) {
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if (!empty($id)) { // to prevent accidental removal of all files in the area
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$fs->delete_area_files($PAGE->context->id, 'workshopform_accumulative', 'description', $id);
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}
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}
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$DB->delete_records_list('workshopform_accumulative', 'id', $ids);
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}
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/**
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* Prepares data returned by {@link workshop_edit_accumulative_strategy_form} so they can be saved into database
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*
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* It automatically adds some columns into every record. The sorting is
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* done by the order of the returned array and starts with 1.
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* Called internally from {@link save_edit_strategy_form()} only. Could be private but
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* keeping protected for unit testing purposes.
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*
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* @param stdClass $raw Raw data returned by mform
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* @return array Array of objects to be inserted/updated in DB
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*/
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protected function prepare_database_fields(stdclass $raw) {
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global $PAGE;
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$cook = new stdclass(); // to be returned
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$cook->accumulative = array(); // records to be stored in {workshopform_accumulative}
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for ($i = 0; $i < $raw->norepeats; $i++) {
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$cook->accumulative[$i] = new stdclass();
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$cook->accumulative[$i]->id = $raw->{'dimensionid__idx_'.$i};
|
|
$cook->accumulative[$i]->workshopid = $this->workshop->id;
|
|
$cook->accumulative[$i]->sort = $i + 1;
|
|
$cook->accumulative[$i]->description_editor = $raw->{'description__idx_'.$i.'_editor'};
|
|
$cook->accumulative[$i]->grade = $raw->{'grade__idx_'.$i};
|
|
$cook->accumulative[$i]->weight = $raw->{'weight__idx_'.$i};
|
|
}
|
|
return $cook;
|
|
}
|
|
|
|
/**
|
|
* Returns the list of current grades filled by the reviewer indexed by dimensionid
|
|
*
|
|
* @param stdClass $assessment Assessment record
|
|
* @return array [int dimensionid] => stdclass workshop_grades record
|
|
*/
|
|
protected function get_current_assessment_data(stdclass $assessment) {
|
|
global $DB;
|
|
|
|
if (empty($this->dimensions)) {
|
|
return array();
|
|
}
|
|
list($dimsql, $dimparams) = $DB->get_in_or_equal(array_keys($this->dimensions), SQL_PARAMS_NAMED);
|
|
// beware! the caller may rely on the returned array is indexed by dimensionid
|
|
$sql = "SELECT dimensionid, wg.*
|
|
FROM {workshop_grades} wg
|
|
WHERE assessmentid = :assessmentid AND strategy= :strategy AND dimensionid $dimsql";
|
|
$params = array('assessmentid' => $assessment->id, 'strategy' => 'accumulative');
|
|
$params = array_merge($params, $dimparams);
|
|
|
|
return $DB->get_records_sql($sql, $params);
|
|
}
|
|
|
|
/**
|
|
* Aggregates the assessment form data and sets the grade for the submission given by the peer
|
|
*
|
|
* @param stdClass $assessment Assessment record
|
|
* @return float|null Raw grade (from 0.00000 to 100.00000) for submission as suggested by the peer
|
|
*/
|
|
protected function update_peer_grade(stdclass $assessment) {
|
|
$grades = $this->get_current_assessment_data($assessment);
|
|
$suggested = $this->calculate_peer_grade($grades);
|
|
if (!is_null($suggested)) {
|
|
$this->workshop->set_peer_grade($assessment->id, $suggested);
|
|
}
|
|
return $suggested;
|
|
}
|
|
|
|
/**
|
|
* Calculates the aggregated grade given by the reviewer
|
|
*
|
|
* @param array $grades Grade records as returned by {@link get_current_assessment_data}
|
|
* @uses $this->dimensions
|
|
* @return float|null Raw grade (from 0.00000 to 100.00000) for submission as suggested by the peer
|
|
*/
|
|
protected function calculate_peer_grade(array $grades) {
|
|
|
|
if (empty($grades)) {
|
|
return null;
|
|
}
|
|
$sumgrades = 0;
|
|
$sumweights = 0;
|
|
foreach ($grades as $grade) {
|
|
$dimension = $this->dimensions[$grade->dimensionid];
|
|
if ($dimension->weight < 0) {
|
|
throw new coding_exception('Negative weights are not supported any more. Something is wrong with your data');
|
|
}
|
|
if (grade_floats_equal($dimension->weight, 0) or grade_floats_equal($dimension->grade, 0)) {
|
|
// does not influence the final grade
|
|
continue;
|
|
}
|
|
if ($dimension->grade < 0) {
|
|
// this is a scale
|
|
$scaleid = -$dimension->grade;
|
|
$sumgrades += $this->scale_to_grade($scaleid, $grade->grade) * $dimension->weight * 100;
|
|
$sumweights += $dimension->weight;
|
|
} else {
|
|
// regular grade
|
|
$sumgrades += ($grade->grade / $dimension->grade) * $dimension->weight * 100;
|
|
$sumweights += $dimension->weight;
|
|
}
|
|
}
|
|
|
|
if ($sumweights === 0) {
|
|
return 0;
|
|
}
|
|
return grade_floatval($sumgrades / $sumweights);
|
|
}
|
|
|
|
/**
|
|
* Convert scale grade to numerical grades
|
|
*
|
|
* In accumulative grading strategy, scales are considered as grades from 0 to M-1, where M is the number of scale items.
|
|
*
|
|
* @throws coding_exception
|
|
* @param string $scaleid Scale identifier
|
|
* @param int $item Selected scale item number, numbered 1, 2, 3, ... M
|
|
* @return float
|
|
*/
|
|
protected function scale_to_grade($scaleid, $item) {
|
|
global $DB;
|
|
|
|
/** @var cache of numbers of scale items */
|
|
static $numofscaleitems = array();
|
|
|
|
if (!isset($numofscaleitems[$scaleid])) {
|
|
$scale = $DB->get_field('scale', 'scale', array('id' => $scaleid), MUST_EXIST);
|
|
$items = explode(',', $scale);
|
|
$numofscaleitems[$scaleid] = count($items);
|
|
unset($scale);
|
|
unset($items);
|
|
}
|
|
|
|
if ($numofscaleitems[$scaleid] <= 1) {
|
|
throw new coding_exception('Invalid scale definition, no scale items found');
|
|
}
|
|
|
|
if ($item <= 0 or $numofscaleitems[$scaleid] < $item) {
|
|
throw new coding_exception('Invalid scale item number');
|
|
}
|
|
|
|
return ($item - 1) / ($numofscaleitems[$scaleid] - 1);
|
|
}
|
|
}
|