moodle/lib/gradelib.php
2007-06-07 08:34:04 +00:00

543 lines
21 KiB
PHP

<?php // $Id$
///////////////////////////////////////////////////////////////////////////
// //
// NOTICE OF COPYRIGHT //
// //
// Moodle - Modular Object-Oriented Dynamic Learning Environment //
// http://moodle.com //
// //
// Copyright (C) 2001-2003 Martin Dougiamas http://dougiamas.com //
// //
// 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; either version 2 of the License, or //
// (at your option) any later version. //
// //
// 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: //
// //
// http://www.gnu.org/copyleft/gpl.html //
// //
///////////////////////////////////////////////////////////////////////////
/**
* Library of functions for gradebook
*
* @author Moodle HQ developers
* @version $Id$
* @license http://www.gnu.org/copyleft/gpl.html GNU Public License
* @package moodlecore
*/
define('GRADE_AGGREGATE_MEAN', 0);
define('GRADE_AGGREGATE_MEDIAN', 1);
define('GRADE_AGGREGATE_SUM', 2);
define('GRADE_AGGREGATE_MODE', 3);
define('GRADE_CHILDTYPE_ITEM', 0);
define('GRADE_CHILDTYPE_CAT', 1);
define('GRADE_ITEM', 0); // Used to compare class names with CHILDTYPE values
define('GRADE_CATEGORY', 1); // Used to compare class names with CHILDTYPE values
define('GRADE_TYPE_NONE', 0);
define('GRADE_TYPE_VALUE', 1);
define('GRADE_TYPE_SCALE', 2);
define('GRADE_TYPE_TEXT', 3);
define('GRADE_UPDATE_OK', 0);
define('GRADE_UPDATE_FAILED', 1);
define('GRADE_UPDATE_MULTIPLE', 2);
define('GRADE_UPDATE_ITEM_DELETED', 3);
define('GRADE_UPDATE_INVALID_GRADE', 4);
define('GRADE_UPDATE_LOCKED', 5);
require_once($CFG->libdir . '/grade/grade_category.php');
require_once($CFG->libdir . '/grade/grade_item.php');
require_once($CFG->libdir . '/grade/grade_calculation.php');
require_once($CFG->libdir . '/grade/grade_grades_raw.php');
require_once($CFG->libdir . '/grade/grade_grades_final.php');
require_once($CFG->libdir . '/grade/grade_scale.php');
require_once($CFG->libdir . '/grade/grade_outcome.php');
require_once($CFG->libdir . '/grade/grade_history.php');
require_once($CFG->libdir . '/grade/grade_grades_text.php');
require_once($CFG->libdir . '/grade/grade_tree.php');
/***** PUBLIC GRADE API *****/
/**
* Submit new or update grade; update/create grade_item definition. Grade must have userid specified,
* gradevalue and feedback with format are optional. gradevalue NULL means 'Not graded', missing property
* or key means do not change existing.
*
* Only following grade item properties can be changed 'itemname', 'idnumber', 'gradetype', 'grademax',
* 'grademin', 'scaleid', 'deleted'.
*
* @param string $source source of the grade such as 'mod/assignment', often used to prevent infinite loops when processing grade_updated events
* @param int $courseid id of course
* @param string $itemtype type of grade item - mod, block, gradecategory, calculated
* @param string $itemmodule more specific then $itemtype - assignment, forum, etc.; maybe NULL for some item types
* @param int $iteminstance instance it of graded subject
* @param int $itemnumber most probably 0, modules can use other numbers when having more than one grades for each user
* @param mixed $grades grade (object, array) or several grades (arrays of arrays or objects), NULL if updating rgade_item definition only\
* @param mixed $itemdetails object or array describing the grading item, NULL if no change
*/
function grade_update($source, $courseid, $itemtype, $itemmodule, $iteminstance, $itemnumber, $grades=NULL, $itemdetails=NULL) {
// only following grade_item properties can be changed in this function
$allowed = array('itemname', 'idnumber', 'gradetype', 'grademax', 'grademin', 'scaleid', 'deleted');
if (is_null($courseid) or is_null($itemtype)) {
debugging('Missing courseid or itemtype');
return GRADE_UPDATE_FAILED;
}
$grade_item = new grade_item(compact('courseid', 'itemtype', 'itemmodule', 'iteminstance', 'itemnumber'), false);
if (!$grade_items = $grade_item->fetch_all_using_this()) {
// create a new one
$grade_item = false;
} else if (count($grade_items) == 1){
$grade_item = reset($grade_items);
unset($grade_items); //release memory
} else {
debugging('Found more than one grading item');
return GRADE_UPDATE_MULTIPLE;
}
/// Create or update the grade_item if needed
if (!$grade_item) {
$params = compact('courseid', 'itemtype', 'itemmodule', 'iteminstance', 'itemnumber');
if ($itemdetails) {
$itemdetails = (array)$itemdetails;
foreach ($itemdetails as $k=>$v) {
if (!in_array($k, $allowed)) {
// ignore it
continue;
}
if ($k == 'gradetype' and $v == GRADE_TYPE_NONE) {
// no grade item needed!
return GRADE_UPDATE_OK;
}
$params[$k] = $v;
}
}
$itemid = grade_create_item($params);
$grade_item = grade_item::fetch('id', $itemid);
} else {
if ($grade_item->locked) {
debugging('Grading item is locked!');
return GRADE_UPDATE_LOCKED;
}
if ($itemdetails) {
$itemdetails = (array)$itemdetails;
$update = false;
foreach ($itemdetails as $k=>$v) {
if (!in_array($k, $allowed)) {
// ignore it
continue;
}
if ($grade_item->{$k} != $v) {
$grade_item->{$k} = $v;
$update = true;
}
}
if ($update) {
$grade_item->update();
}
}
}
/// Some extra checks
// do we use grading?
if ($grade_item->gradetype == GRADE_TYPE_NONE) {
return GRADE_UPDATE_OK;
}
// no grade submitted
if (empty($grades)) {
return GRADE_UPDATE_OK;
}
// no grading in deleted items
if ($grade_item->deleted) {
debugging('Grade item was already deleted!');
return GRADE_UPDATE_ITEM_DELETED;
}
/// Finally start processing of grades
if (is_object($grades)) {
$grades = array($grades);
} else {
if (array_key_exists('userid', $grades)) {
$grades = array($grades);
}
}
foreach ($grades as $grade) {
$grade = (array)$grade;
if (empty($grade['userid'])) {
debugging('Invalid grade submitted');
return GRADE_UPDATE_INVALID_GRADE;
}
// get the raw grade if it exist
$rawgrade = new grade_grades_raw(array('itemid'=>$grade_item->id, 'userid'=>$grade['userid']));
$rawgrade->grade_item = &$grade_item; // we already have it, so let's use it
// store these to keep track of original grade item settings
$rawgrade->grademax = $grade_item->grademax;
$rawgrade->grademin = $grade_item->grademin;
$rawgrade->scaleid = $grade_item->scaleid;
if (isset($grade['feedback'])) {
$rawgrade->feedback = $grade['feedback'];
if (isset($grade['feedbackformat'])) {
$rawgrade->feedbackformat = $grade['feedbackformat'];
} else {
$rawgrade->feedbackformat = FORMAT_PLAIN;
}
}
if (!isset($grade['gradevalue'])) {
$grade['gradevalue'] = null; // means no grade yet
}
if ($rawgrade->id) {
$rawgrade->update($grade['gradevalue'], 'event');
} else {
$rawgrade->gradevalue = $grade['gradevalue'];
$rawgrade->insert();
}
// trigger grade_updated event notification
$eventdata = new object();
$eventdata->source = $source;
$eventdata->itemid = $grade_item->id;
$eventdata->courseid = $grade_item->courseid;
$eventdata->itemtype = $grade_item->itemtype;
$eventdata->itemmodule = $grade_item->itemmodule;
$eventdata->iteminstance = $grade_item->iteminstance;
$eventdata->itemnumber = $grade_item->itemnumber;
$eventdata->idnumber = $grade_item->idnumber;
$eventdata->grade = $grade;
events_trigger('grade_updated', $eventdata);
}
return GRADE_UPDATE_OK;
}
/**
* Tells a module whether a grade (or grade_item if $userid is not given) is currently locked or not.
* This is a combination of the actual settings in the grade tables and a check on moodle/course:editgradeswhenlocked.
* If it's locked to the current use then the module can print a nice message or prevent editing in the module.
* If no $userid is given, the method will always return the grade_item's locked state.
* If a $userid is given, the method will first check the grade_item's locked state (the column). If it is locked,
* the method will return true no matter the locked state of the specific grade being checked. If unlocked, it will
* return the locked state of the specific grade.
*
* @param string $itemtype 'mod', 'blocks', 'import', 'calculated' etc
* @param string $itemmodule 'forum, 'quiz', 'csv' etc
* @param int $iteminstance id of the item module
* @param int $itemnumber Optional number of the item to check
* @param int $userid ID of the user who owns the grade
* @return boolean Whether the grade is locked or not
*/
function grade_is_locked($itemtype, $itemmodule, $iteminstance, $itemnumber=NULL, $userid=NULL) {
$grade_item = new grade_item(compact('itemtype', 'itemmodule', 'iteminstance', 'itemnumber'));
return $grade_item->is_locked($userid);
}
/***** END OF PUBLIC API *****/
/**
* Extracts from the gradebook all the grade items attached to the calling object.
* For example, an assignment may want to retrieve all the grade_items for itself,
* and get three outcome scales in return. This will affect the grading interface.
*
* Note: Each parameter refines the search. So if you only give the courseid,
* all the grade_items for this course will be returned. If you add the
* itemtype 'mod', all grade_items for this courseif AND for the 'mod'
* type will be returned, etc...
*
* @param int $courseid The id of the course to which the grade items belong
* @param string $itemtype 'mod', 'blocks', 'import', 'calculated' etc
* @param string $itemmodule 'forum, 'quiz', 'csv' etc
* @param int $iteminstance id of the item module
* @param string $itemname The name of the grade item
* @param int $itemnumber Can be used to distinguish multiple grades for an activity
* @param int $idnumber grade item Primary Key
* @return array An array of grade items
*/
function grade_get_items($courseid, $itemtype=NULL, $itemmodule=NULL, $iteminstance=NULL, $itemname=NULL, $itemnumber=NULL, $idnumber=NULL) {
$grade_item = new grade_item(compact('courseid', 'itemtype', 'itemmodule', 'iteminstance', 'itemname', 'itemnumber', 'idnumber'), false);
$grade_items = $grade_item->fetch_all_using_this();
return $grade_items;
}
/**
* Creates a new grade_item in case it doesn't exist.
* This function is called when a new module is created.
*
* @param mixed $params array or object
* @return mixed New grade_item id if successful
*/
function grade_create_item($params) {
$grade_item = new grade_item($params);
if (empty($grade_item->id)) {
return $grade_item->insert();
} else {
debugging('Grade item already exists - id:'.$grade_item->id);
return $grade_item->id;
}
}
/**
* For a given set of items, create a category to group them together (if one doesn't yet exist).
* Modules may want to do this when they are created. However, the ultimate control is in the gradebook interface itself.
*
* @param int $courseid
* @param string $fullname The name of the new category
* @param array $items An array of grade_items to group under the new category
* @param string $aggregation
* @return mixed New grade_category id if successful
*/
function grade_create_category($courseid, $fullname, $items, $aggregation=GRADE_AGGREGATE_MEAN) {
$grade_category = new grade_category(compact('courseid', 'fullname', 'items', 'aggregation'));
if (empty($grade_category->id)) {
return $grade_category->insert();
} else {
return $grade_category->id;
}
}
/**
* Updates all grade_grades_final for each grade_item matching the given attributes.
* The search is further restricted, so that only grade_items that have needs_update == TRUE
* or that use calculation are retrieved.
*
* @param int $courseid
* @param int $gradeitemid
* @return int Number of grade_items updated
*/
function grade_update_final_grades($courseid=NULL, $gradeitemid=NULL) {
$grade_item = new grade_item();
$grade_item->courseid = $courseid;
$grade_item->id = $gradeitemid;
$grade_items = $grade_item->fetch_all_using_this();
$count = 0;
foreach ($grade_items as $gi) {
$calculation = $gi->get_calculation();
if (!empty($calculation) || $gi->needsupdate) {
if ($gi->update_final_grade()) {
$count++;
}
}
}
return $count;
}
/**
* For backward compatibility with old third-party modules, this function is called
* via to admin/cron.php to search all mod/xxx/lib.php files for functions named xxx_grades(),
* if the current modules does not have grade events registered with the grade book.
* Once the data is extracted, the events_trigger() function can be called to initiate
* an event as usual and copy/ *upgrade the data in the gradebook tables.
*/
function grade_grab_legacy_grades() {
global $CFG, $db;
if (!$mods = get_list_of_plugins('mod') ) {
error('No modules installed!');
}
foreach ($mods as $mod) {
if ($mod == 'NEWMODULE') { // Someone has unzipped the template, ignore it
continue;
}
$fullmod = $CFG->dirroot .'/mod/'. $mod;
// include the module lib once
if (file_exists($fullmod.'/lib.php')) {
include_once($fullmod.'/lib.php');
// look for modname_grades() function - old gradebook pulling function
// if present sync the grades with new grading system
$gradefunc = $mod.'_grades';
if (function_exists($gradefunc)) {
// get all instance of the activity
$sql = "SELECT a.*, cm.idnumber as cmidnumber, a.course as courseid, m.name as modname FROM {$CFG->prefix}$mod a, {$CFG->prefix}course_modules cm, {$CFG->prefix}modules m
WHERE m.name='$mod' AND m.id=cm.module AND cm.instance=a.id";
if ($modinstances = get_records_sql($sql)) {
foreach ($modinstances as $modinstance) {
// for each instance, call the xxx_grades() function
if ($grades = $gradefunc($modinstance->id)) {
$grademax = $grades->maxgrade;
$scaleid = 0;
if (!is_numeric($grademax)) {
// scale name is provided as a string, try to find it
if (!$scale = get_record('scale', 'name', $grademax)) {
debugging('Incorrect scale name! name:'.$grademax);
continue;
}
$scaleid = $scale->id;
}
if (!$grade_item = grade_get_legacy_grade_item($modinstance, $grademax, $scaleid)) {
debugging('Can not get/create legacy grade item!');
continue;
}
foreach ($grades->grades as $userid=>$usergrade) {
// make the grade_added eventdata
$eventdata = new object();
$eventdata->itemid = $grade_item->id;
$eventdata->userid = $userid;
if ($usergrade == '-') {
// no grade
$eventdata->gradevalue = null;
} else if ($scaleid) {
// scale in use, words used
$gradescale = explode(",", $scale->scale);
$eventdata->gradevalue = array_search($usergrade, $gradescale) + 1;
} else {
// good old numeric value
$eventdata->gradevalue = $usergrade;
}
events_trigger('grade_updated', $eventdata);
}
}
}
}
}
}
}
}
/**
* Get (create if needed) grade item for legacy modules.
*/
function grade_get_legacy_grade_item($modinstance, $grademax, $scaleid) {
// does it already exist?
if ($grade_items = grade_get_items($modinstances->courseid, 'mod', $modinstance->modname, $modinstances->id)) {
if (count($grade_items) > 1) {
return false;
}
$grade_item = reset($grade_items);
$updated = false;
if ($scaleid) {
if ($grade_item->scaleid != $scaleid) {
$grade_item->gradetype = GRADE_TYPE_SCALE;
$grade_item->scaleid = $scaleid;
$updated = true;;
}
} else if ($grade_item->scaleid != $scaleid or $grade_item->grademax != $grademax) {
$grade_item->gradetype = GRADE_TYPE_VALUE;
$grade_item->scaleid = 0;
$grade_item->grademax = $grademax;
$grade_item->grademin = 0;
$updated = true;;
}
if ($grade_item->itemname != $modinstance->name) {
$grade_item->itemname = $modinstance->name;
$updated = true;;
}
if ($grade_item->idnumber != $modinstance->cmidnumber) {
$grade_item->idnumber = $modinstance->cmidnumber;
$updated = true;;
}
if ($updated) {
$grade_item->update();
}
return $grade_item;
}
// create new one
$params = array('courseid' =>$modinstance->courseid,
'itemtype' =>'mod',
'itemmodule' =>$modinstance->modname,
'iteminstance'=>$modinstance->id,
'itemname' =>$modinstance->name,
'idnumber' =>$modinstance->cmidnumber);
if ($scaleid) {
$params['gradetype'] = GRADE_TYPE_SCALE;
$params['scaleid'] = $scaleid;
} else {
$params['gradetype'] = GRADE_TYPE_VALUE;
$params['grademax'] = $grademax;
$params['grademin'] = 0;
}
if (!$itemid = grade_create_item($params)) {
return false;
}
return grade_item::fetch('id', $itemid);
}
/**
* Given a float value situated between a source minimum and a source maximum, converts it to the
* corresponding value situated between a target minimum and a target maximum. Thanks to Darlene
* for the formula :-)
* @param float $gradevalue
* @param float $source_min
* @param float $source_max
* @param float $target_min
* @param float $target_max
* @return float Converted value
*/
function standardise_score($gradevalue, $source_min, $source_max, $target_min, $target_max, $debug=false) {
$factor = ($gradevalue - $source_min) / ($source_max - $source_min);
$diff = $target_max - $target_min;
$standardised_value = $factor * $diff + $target_min;
if ($debug) {
echo 'standardise_score debug info: (lib/gradelib.php)';
print_object(array('gradevalue' => $gradevalue,
'source_min' => $source_min,
'source_max' => $source_max,
'target_min' => $target_min,
'target_max' => $target_max,
'result' => $standardised_value));
}
return $standardised_value;
}
?>