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<?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 defines a class with "Number of errors" grading strategy logic** @package workshopform_numerrors* @copyright 2009 David Mudrak <david.mudrak@gmail.com>* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later*/defined('MOODLE_INTERNAL') || die();require_once(__DIR__ . '/../lib.php'); // Interface definition.require_once($CFG->libdir . '/gradelib.php'); // To handle float vs decimal issues./*** Server workshop files** @category files* @param stdClass $course course object* @param stdClass $cm course module object* @param stdClass $context context object* @param string $filearea file area* @param array $args extra arguments* @param bool $forcedownload whether or not force download* @param array $options additional options affecting the file serving* @return bool*/function workshopform_numerrors_pluginfile($course, $cm, $context, $filearea, array $args, $forcedownload, array $options=array()) {global $DB;if ($context->contextlevel != CONTEXT_MODULE) {return false;}require_login($course, true, $cm);if ($filearea !== 'description') {return false;}$itemid = (int)array_shift($args); // the id of the assessment form dimensionif (!$workshop = $DB->get_record('workshop', array('id' => $cm->instance))) {send_file_not_found();}if (!$dimension = $DB->get_record('workshopform_numerrors', array('id' => $itemid ,'workshopid' => $workshop->id))) {send_file_not_found();}// TODO now make sure the user is allowed to see the file// (media embedded into the dimension description)$fs = get_file_storage();$relativepath = implode('/', $args);$fullpath = "/$context->id/workshopform_numerrors/$filearea/$itemid/$relativepath";if (!$file = $fs->get_file_by_hash(sha1($fullpath)) or $file->is_directory()) {return false;}// finally send the filesend_stored_file($file, 0, 0, $forcedownload, $options);}/*** "Number of errors" grading strategy logic.*/class workshop_numerrors_strategy implements workshop_strategy {/** @var default number of dimensions to show */const MINDIMS = 3;/** @var number of dimensions to add */const ADDDIMS = 2;/** @var workshop the parent workshop instance */protected $workshop;/** @var array definition of the assessment form fields */protected $dimensions = null;/** @var array mapping of the number of errors to a grade */protected $mappings = null;/** @var array options for dimension description fields */protected $descriptionopts;/*** Constructor** @param workshop $workshop The workshop instance record* @return void*/public function __construct(workshop $workshop) {$this->workshop = $workshop;$this->dimensions = $this->load_fields();$this->mappings = $this->load_mappings();$this->descriptionopts = array('trusttext' => true, 'subdirs' => false, 'maxfiles' => -1);}/*** Factory method returning an instance of an assessment form editor class** @param $actionurl URL of form handler, defaults to auto detect the current url*/public function get_edit_strategy_form($actionurl=null) {global $CFG; // needed because the included files use itglobal $PAGE;require_once(__DIR__ . '/edit_form.php');$fields = $this->prepare_form_fields($this->dimensions, $this->mappings);$nodimensions = count($this->dimensions);$norepeatsdefault = max($nodimensions + self::ADDDIMS, self::MINDIMS);$norepeats = optional_param('norepeats', $norepeatsdefault, PARAM_INT); // number of dimensions$noadddims = optional_param('noadddims', '', PARAM_ALPHA); // shall we add more?if ($noadddims) {$norepeats += self::ADDDIMS;}// Append editor context to editor options, giving preference to existing context.$this->descriptionopts = array_merge(array('context' => $PAGE->context), $this->descriptionopts);// prepare the embeded filesfor ($i = 0; $i < $nodimensions; $i++) {// prepare all editor elements$fields = file_prepare_standard_editor($fields, 'description__idx_'.$i, $this->descriptionopts,$PAGE->context, 'workshopform_numerrors', 'description', $fields->{'dimensionid__idx_'.$i});}$customdata = array();$customdata['workshop'] = $this->workshop;$customdata['strategy'] = $this;$customdata['norepeats'] = $norepeats;$customdata['nodimensions'] = $nodimensions;$customdata['descriptionopts'] = $this->descriptionopts;$customdata['current'] = $fields;$attributes = array('class' => 'editstrategyform');return new workshop_edit_numerrors_strategy_form($actionurl, $customdata, 'post', '', $attributes);}/*** Save the assessment dimensions into database** Saves data into the main strategy form table. If the record->id is null or zero,* new record is created. If the record->id is not empty, the existing record is updated. Records with* empty 'description' field are removed from database.* The passed data object are the raw data returned by the get_data().** @uses $DB* @param stdClass $data Raw data returned by the dimension editor form* @return void*/public function save_edit_strategy_form(stdclass $data) {global $DB, $PAGE;$workshopid = $data->workshopid;$norepeats = $data->norepeats;$data = $this->prepare_database_fields($data);$records = $data->numerrors; // data to be saved into {workshopform_numerrors}$mappings = $data->mappings; // data to be saved into {workshopform_numerrors_map}$todelete = array(); // dimension ids to be deleted$maxnonegative = 0; // maximum number of (weighted) negative responsesfor ($i=0; $i < $norepeats; $i++) {$record = $records[$i];if (0 == strlen(trim($record->description_editor['text']))) {if (!empty($record->id)) {// existing dimension record with empty description - to be deleted$todelete[] = $record->id;}continue;}if (empty($record->id)) {// new field$record->id = $DB->insert_record('workshopform_numerrors', $record);} else {// exiting field$DB->update_record('workshopform_numerrors', $record);}$maxnonegative += $record->weight;// re-save with correct path to embeded media files$record = file_postupdate_standard_editor($record, 'description', $this->descriptionopts, $PAGE->context,'workshopform_numerrors', 'description', $record->id);$DB->update_record('workshopform_numerrors', $record);}$this->delete_dimensions($todelete);// re-save the mappings$todelete = array();foreach ($data->mappings as $nonegative => $grade) {if (is_null($grade)) {// no grade set for this number of negative responses$todelete[] = $nonegative;continue;}if (isset($this->mappings[$nonegative])) {$DB->set_field('workshopform_numerrors_map', 'grade', $grade,array('workshopid' => $this->workshop->id, 'nonegative' => $nonegative));} else {$DB->insert_record('workshopform_numerrors_map',(object)array('workshopid' => $this->workshop->id, 'nonegative' => $nonegative, 'grade' => $grade));}}// clear mappings that are not valid any moreif (!empty($todelete)) {list($insql, $params) = $DB->get_in_or_equal($todelete, SQL_PARAMS_NAMED);$insql = "nonegative $insql OR ";} else {$insql = '';}$sql = "DELETE FROM {workshopform_numerrors_map}WHERE (($insql nonegative > :maxnonegative) AND (workshopid = :workshopid))";$params['maxnonegative'] = $maxnonegative;$params['workshopid'] = $this->workshop->id;$DB->execute($sql, $params);}/*** Factory method returning an instance of an assessment form** @param moodle_url $actionurl URL of form handler, defaults to auto detect the current url* @param string $mode Mode to open the form in: preview/assessment* @param stdClass $assessment* @param bool $editable* @param array $options*/public function get_assessment_form(moodle_url $actionurl=null, $mode='preview', stdclass $assessment=null, $editable=true, $options=array()) {global $CFG; // needed because the included files use itglobal $PAGE;global $DB;require_once(__DIR__ . '/assessment_form.php');$fields = $this->prepare_form_fields($this->dimensions, $this->mappings);$nodimensions = count($this->dimensions);// rewrite URLs to the embeded filesfor ($i = 0; $i < $nodimensions; $i++) {$fields->{'description__idx_'.$i} = file_rewrite_pluginfile_urls($fields->{'description__idx_'.$i},'pluginfile.php', $PAGE->context->id, 'workshopform_numerrors', 'description', $fields->{'dimensionid__idx_'.$i});}if ('assessment' === $mode and !empty($assessment)) {// load the previously saved assessment data$grades = $this->get_current_assessment_data($assessment);$current = new stdclass();for ($i = 0; $i < $nodimensions; $i++) {$dimid = $fields->{'dimensionid__idx_'.$i};if (isset($grades[$dimid])) {$current->{'gradeid__idx_'.$i} = $grades[$dimid]->id;$current->{'grade__idx_'.$i} = ($grades[$dimid]->grade == 0 ? -1 : 1);$current->{'peercomment__idx_'.$i} = $grades[$dimid]->peercomment;}}}// set up the required custom data common for all strategies$customdata['workshop'] = $this->workshop;$customdata['strategy'] = $this;$customdata['mode'] = $mode;$customdata['options'] = $options;// set up strategy-specific custom data$customdata['nodims'] = $nodimensions;$customdata['fields'] = $fields;$customdata['current'] = isset($current) ? $current : null;$attributes = array('class' => 'assessmentform numerrors');return new workshop_numerrors_assessment_form($actionurl, $customdata, 'post', '', $attributes, $editable);}/*** Saves the filled assessment** This method processes data submitted using the form returned by {@link get_assessment_form()}** @param stdClass $assessment Assessment being filled* @param stdClass $data Raw data as returned by the assessment form* @return float|null Raw grade (from 0.00000 to 100.00000) for submission as suggested by the peer*/public function save_assessment(stdclass $assessment, stdclass $data) {global $DB;if (!isset($data->nodims)) {throw new coding_exception('You did not send me the number of assessment dimensions to process');}for ($i = 0; $i < $data->nodims; $i++) {$grade = new stdclass();$grade->id = $data->{'gradeid__idx_' . $i};$grade->assessmentid = $assessment->id;$grade->strategy = 'numerrors';$grade->dimensionid = $data->{'dimensionid__idx_' . $i};$grade->grade = ($data->{'grade__idx_' . $i} <= 0 ? 0 : 1);$grade->peercomment = $data->{'peercomment__idx_' . $i};$grade->peercommentformat = FORMAT_HTML;if (empty($grade->id)) {// new grade$grade->id = $DB->insert_record('workshop_grades', $grade);} else {// updated grade$DB->update_record('workshop_grades', $grade);}}return $this->update_peer_grade($assessment);}/*** Has the assessment form been defined and is ready to be used by the reviewers?** @return boolean*/public function form_ready() {if (count($this->dimensions) > 0) {return true;}return false;}/*** @see parent::get_assessments_recordset()*/public function get_assessments_recordset($restrict=null) {global $DB;$sql = 'SELECT s.id AS submissionid,a.id AS assessmentid, a.weight AS assessmentweight, a.reviewerid, a.gradinggrade,g.dimensionid, g.gradeFROM {workshop_submissions} sJOIN {workshop_assessments} a ON (a.submissionid = s.id)JOIN {workshop_grades} g ON (g.assessmentid = a.id AND g.strategy = :strategy)WHERE s.example=0 AND s.workshopid=:workshopid'; // to be cont.$params = array('workshopid' => $this->workshop->id, 'strategy' => $this->workshop->strategy);if (is_null($restrict)) {// update all users - no more conditions} elseif (!empty($restrict)) {list($usql, $uparams) = $DB->get_in_or_equal($restrict, SQL_PARAMS_NAMED);$sql .= " AND a.reviewerid $usql";$params = array_merge($params, $uparams);} else {throw new coding_exception('Empty value is not a valid parameter here');}$sql .= ' ORDER BY s.id'; // this is important for bulk processingreturn $DB->get_recordset_sql($sql, $params);}/*** @see parent::get_dimensions_info()*/public function get_dimensions_info() {global $DB;$params = array('workshopid' => $this->workshop->id);$dimrecords = $DB->get_records('workshopform_numerrors', array('workshopid' => $this->workshop->id), 'sort', 'id,weight');foreach ($dimrecords as $dimid => $dimrecord) {$dimrecords[$dimid]->min = 0;$dimrecords[$dimid]->max = 1;}return $dimrecords;}/*** Is a given scale used by the instance of workshop?** This grading strategy does not use scales.** @param int $scaleid id of the scale to check* @param int|null $workshopid id of workshop instance to check, checks all in case of null* @return bool*/public static function scale_used($scaleid, $workshopid=null) {return false;}/*** Delete all data related to a given workshop module instance** @see workshop_delete_instance()* @param int $workshopid id of the workshop module instance being deleted* @return void*/public static function delete_instance($workshopid) {global $DB;$DB->delete_records('workshopform_numerrors', array('workshopid' => $workshopid));$DB->delete_records('workshopform_numerrors_map', array('workshopid' => $workshopid));}////////////////////////////////////////////////////////////////////////////////// Internal methods ///////////////////////////////////////////////////////////////////////////////////*** Loads the fields of the assessment form currently used in this workshop** @return array definition of assessment dimensions*/protected function load_fields() {global $DB;$sql = 'SELECT *FROM {workshopform_numerrors}WHERE workshopid = :workshopidORDER BY sort';$params = array('workshopid' => $this->workshop->id);return $DB->get_records_sql($sql, $params);}/*** Loads the mappings of the number of errors to the grade** @return array of records*/protected function load_mappings() {global $DB;return $DB->get_records('workshopform_numerrors_map', array('workshopid' => $this->workshop->id), 'nonegative','nonegative,grade'); // we can use nonegative as key here as it must be unique within workshop}/*** Prepares the database data to be used by the mform** @param array $dims Array of raw dimension records as returned by {@link load_fields()}* @param array $maps Array of raw mapping records as returned by {@link load_mappings()}* @return array Array of fields data to be used by the mform set_data*/protected function prepare_form_fields(array $dims, array $maps) {$formdata = new stdclass();$key = 0;foreach ($dims as $dimension) {$formdata->{'dimensionid__idx_' . $key} = $dimension->id;$formdata->{'description__idx_' . $key} = $dimension->description;$formdata->{'description__idx_' . $key.'format'} = $dimension->descriptionformat;$formdata->{'grade0__idx_' . $key} = $dimension->grade0;$formdata->{'grade1__idx_' . $key} = $dimension->grade1;$formdata->{'weight__idx_' . $key} = $dimension->weight;$key++;}foreach ($maps as $nonegative => $map) {$formdata->{'map__idx_' . $nonegative} = $map->grade;}return $formdata;}/*** Deletes dimensions and removes embedded media from its descriptions** todo we may check that there are no assessments done using these dimensions and probably remove them** @param array $ids list to delete* @return void*/protected function delete_dimensions(array $ids) {global $DB, $PAGE;$fs = get_file_storage();foreach ($ids as $id) {$fs->delete_area_files($PAGE->context->id, 'workshopform_numerrors', 'description', $id);}$DB->delete_records_list('workshopform_numerrors', 'id', $ids);}/*** Prepares data returned by {@link workshop_edit_numerrors_strategy_form} so they can be saved into database** It automatically adds some columns into every record. The sorting is* done by the order of the returned array and starts with 1.* Called internally from {@link save_edit_strategy_form()} only. Could be private but* keeping protected for unit testing purposes.** @param stdClass $raw Raw data returned by mform* @return array Array of objects to be inserted/updated in DB*/protected function prepare_database_fields(stdclass $raw) {global $PAGE;$cook = new stdclass(); // to be returned$cook->numerrors = array(); // to be stored in {workshopform_numerrors}$cook->mappings = array(); // to be stored in {workshopform_numerrors_map}for ($i = 0; $i < $raw->norepeats; $i++) {$cook->numerrors[$i] = new stdclass();$cook->numerrors[$i]->id = $raw->{'dimensionid__idx_'.$i};$cook->numerrors[$i]->workshopid = $this->workshop->id;$cook->numerrors[$i]->sort = $i + 1;$cook->numerrors[$i]->description_editor = $raw->{'description__idx_'.$i.'_editor'};$cook->numerrors[$i]->grade0 = $raw->{'grade0__idx_'.$i};$cook->numerrors[$i]->grade1 = $raw->{'grade1__idx_'.$i};$cook->numerrors[$i]->weight = $raw->{'weight__idx_'.$i};}$i = 1;while (isset($raw->{'map__idx_'.$i})) {if (is_numeric($raw->{'map__idx_'.$i})) {$cook->mappings[$i] = $raw->{'map__idx_'.$i}; // should be a value from 0 to 100} else {$cook->mappings[$i] = null; // the user did not set anything}$i++;}return $cook;}/*** Returns the list of current grades filled by the reviewer** @param stdClass $assessment Assessment record* @return array of filtered records from the table workshop_grades*/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} wgWHERE assessmentid = :assessmentid AND strategy= :strategy AND dimensionid $dimsql";$params = array('assessmentid' => $assessment->id, 'strategy' => 'numerrors');$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 (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}* @return float|null Raw grade (0.00000 to 100.00000) for submission as suggested by the peer*/protected function calculate_peer_grade(array $grades) {if (empty($grades)) {return null;}$sumerrors = 0; // sum of the weighted errors (i.e. the negative responses)foreach ($grades as $grade) {if (grade_floats_different($grade->grade, 1.00000)) {// negative reviewer's response$sumerrors += $this->dimensions[$grade->dimensionid]->weight;}}return $this->errors_to_grade($sumerrors);}/*** Returns a grade 0.00000 to 100.00000 for the given number of errors** This is where we use the mapping table defined by the teacher. If a grade for the given* number of errors (negative assertions) is not defined, the most recently defined one is used.* Example of the defined mapping:* Number of errors | Grade* 0 | 100% (always)* 1 | - (not defined)* 2 | 80%* 3 | 60%* 4 | -* 5 | 30%* 6 | 0%* With this mapping, one error is mapped to 100% grade and 4 errors is mapped to 60%.** @param mixed $numerrors Number of errors* @return float Raw grade (0.00000 to 100.00000) for the given number of negative assertions*/protected function errors_to_grade($numerrors) {$grade = 100.00000;for ($i = 1; $i <= $numerrors; $i++) {if (isset($this->mappings[$i])) {$grade = $this->mappings[$i]->grade;}}if ($grade > 100.00000) {$grade = 100.00000;}if ($grade < 0.00000) {$grade = 0.00000;}return grade_floatval($grade);}}