moodle/lib/grade/grade_grade.php

476 lines
14 KiB
PHP

<?php // $Id$
///////////////////////////////////////////////////////////////////////////
// //
// NOTICE OF COPYRIGHT //
// //
// Moodle - Modular Object-Oriented Dynamic Learning Environment //
// http://moodle.com //
// //
// Copyright (C) 1999 onwards 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 //
// //
///////////////////////////////////////////////////////////////////////////
require_once('grade_object.php');
class grade_grade extends grade_object {
/**
* The DB table.
* @var string $table
*/
var $table = 'grade_grades';
/**
* Array of required table fields, must start with 'id'.
* @var array $required_fields
*/
var $required_fields = array('id', 'itemid', 'userid', 'rawgrade', 'rawgrademax', 'rawgrademin',
'rawscaleid', 'usermodified', 'finalgrade', 'hidden', 'locked',
'locktime', 'exported', 'overridden', 'excluded', 'timecreated', 'timemodified');
/**
* Array of optional fields with default values (these should match db defaults)
* @var array $optional_fields
*/
var $optional_fields = array('feedback'=>null, 'feedbackformat'=>0, 'information'=>null, 'informationformat'=>0);
/**
* The id of the grade_item this grade belongs to.
* @var int $itemid
*/
var $itemid;
/**
* The grade_item object referenced by $this->itemid.
* @var object $grade_item
*/
var $grade_item;
/**
* The id of the user this grade belongs to.
* @var int $userid
*/
var $userid;
/**
* The grade value of this raw grade, if such was provided by the module.
* @var float $rawgrade
*/
var $rawgrade;
/**
* The maximum allowable grade when this grade was created.
* @var float $rawgrademax
*/
var $rawgrademax = 100;
/**
* The minimum allowable grade when this grade was created.
* @var float $rawgrademin
*/
var $rawgrademin = 0;
/**
* id of the scale, if this grade is based on a scale.
* @var int $rawscaleid
*/
var $rawscaleid;
/**
* The userid of the person who last modified this grade.
* @var int $usermodified
*/
var $usermodified;
/**
* The final value of this grade.
* @var float $finalgrade
*/
var $finalgrade;
/**
* 0 if visible, 1 always hidden or date not visible until
* @var float $hidden
*/
var $hidden = 0;
/**
* 0 not locked, date when the item was locked
* @var float locked
*/
var $locked = 0;
/**
* 0 no automatic locking, date when to lock the grade automatically
* @var float $locktime
*/
var $locktime = 0;
/**
* Exported flag
* @var boolean $exported
*/
var $exported = 0;
/**
* Overridden flag
* @var boolean $overridden
*/
var $overridden = 0;
/**
* Grade excluded from aggregation functions
* @var boolean $excluded
*/
var $excluded = 0;
/**
* Returns array of grades for given grade_item+users.
* @param object $grade_item
* @param array $userids
* @param bool $include_missing include grades taht do not exist yet
* @return array userid=>grade_grade array
*/
function fetch_users_grades($grade_item, $userids, $include_missing=true) {
// hmm, there might be a problem with length of sql query
// if there are too many users requested - we might run out of memory anyway
$limit = 2000;
$count = count($userids);
if ($count > $limit) {
$half = (int)($count/2);
$first = array_slice($userids, 0, $half);
$second = array_slice($userids, $half);
return grade_grade::fetch_users_grades($grade_item, $first, $include_missing) + grade_grade::fetch_users_grades($grade_item, $second, $include_missing);
}
$user_ids_cvs = implode(',', $userids);
$result = array();
if ($grade_records = get_records_select('grade_grades', "itemid={$grade_item->id} AND userid IN ($user_ids_cvs)")) {
foreach ($grade_records as $record) {
$result[$record->userid] = new grade_grade($record, false);
}
}
if ($include_missing) {
foreach ($userids as $userid) {
if (!array_key_exists($userid, $result)) {
$grade_grade = new grade_grade();
$grade_grade->userid = $userid;
$grade_grade->itemid = $grade_item->id;
$result[$userid] = $grade_grade;
}
}
}
return $result;
}
/**
* Loads the grade_item object referenced by $this->itemid and saves it as $this->grade_item for easy access.
* @return object grade_item.
*/
function load_grade_item() {
if (empty($this->itemid)) {
debugging('Missing itemid');
$this->grade_item = null;
return null;
}
if (empty($this->grade_item)) {
$this->grade_item = grade_item::fetch(array('id'=>$this->itemid));
} else if ($this->grade_item->id != $this->itemid) {
debugging('Itemid mismatch');
$this->grade_item = grade_item::fetch(array('id'=>$this->itemid));
}
return $this->grade_item;
}
/**
* Is grading object editable?
* @return boolean
*/
function is_editable() {
if ($this->is_locked()) {
return false;
}
$grade_item = $this->load_grade_item();
if ($grade_item->gradetype == GRADE_TYPE_NONE) {
return false;
}
return true;
}
/**
* Check grade lock status. Uses both grade item lock and grade lock.
* Internally any date in locked field (including future ones) means locked,
* the date is stored for logging purposes only.
*
* @return boolean true if locked, false if not
*/
function is_locked() {
$this->load_grade_item();
return !empty($this->locked) or $this->grade_item->is_locked();
}
/**
* Checks if grade overridden
* @return boolean
*/
function is_overridden() {
return !empty($this->overridden);
}
/**
* Set the overridden status of grade
* @param boolean $state requested overridden state
* @return boolean true is db state changed
*/
function set_overridden($state) {
if (empty($this->overridden) and $state) {
$this->overridden = time();
$this->update();
return true;
} else if (!empty($this->overridden) and !$state) {
$this->overridden = 0;
$this->update();
return true;
}
return false;
}
/**
* Checks if grade excluded from aggregation functions
* @return boolean
*/
function is_excluded() {
return !empty($this->excluded);
}
/**
* Set the excluded status of grade
* @param boolean $state requested excluded state
* @return boolean true is db state changed
*/
function set_excluded($state) {
if (empty($this->excluded) and $state) {
$this->excluded = time();
$this->update();
return true;
} else if (!empty($this->excluded) and !$state) {
$this->excluded = 0;
$this->update();
return true;
}
return false;
}
/**
* Lock/unlock this grade.
*
* @param int $locked 0, 1 or a timestamp int(10) after which date the item will be locked.
* @param boolean $cascade ignored param
* @param boolean $refresh refresh grades when unlocking
* @return boolean true if sucessful, false if can not set new lock state for grade
*/
function set_locked($lockedstate, $cascade=false, $refresh=true) {
$this->load_grade_item();
if ($lockedstate) {
if ($this->grade_item->needsupdate) {
//can not lock grade if final not calculated!
return false;
}
$this->locked = time();
$this->update();
return true;
} else {
if (!empty($this->locked) and $this->locktime < time()) {
//we have to reset locktime or else it would lock up again
$this->locktime = 0;
}
// remove the locked flag
$this->locked = 0;
$this->update();
if ($refresh) {
//refresh when unlocking
$this->grade_item->refresh_grades($this->userid);
}
return true;
}
}
/**
* Lock the grade if needed - make sure this is called only when final grades are valid
* @param array $items array of all grade item ids
* @return void
*/
function check_locktime_all($items) {
global $CFG;
$items_sql = implode(',', $items);
$now = time(); // no rounding needed, this is not supposed to be called every 10 seconds
if ($rs = get_recordset_select('grade_grades', "itemid IN ($items_sql) AND locked = 0 AND locktime > 0 AND locktime < $now")) {
while ($grade = rs_fetch_next_record($rs)) {
$grade_grade = new grade_grade($grade, false);
$grade_grade->locked = time();
$grade_grade->update('locktime');
}
rs_close($rs);
}
}
/**
* Set the locktime for this grade.
*
* @param int $locktime timestamp for lock to activate
* @return void
*/
function set_locktime($locktime) {
$this->locktime = $locktime;
$this->update();
}
/**
* Set the locktime for this grade.
*
* @return int $locktime timestamp for lock to activate
*/
function get_locktime() {
$this->load_grade_item();
$item_locktime = $this->grade_item->get_locktime();
if (empty($this->locktime) or ($item_locktime and $item_locktime < $this->locktime)) {
return $item_locktime;
} else {
return $this->locktime;
}
}
/**
* Check grade hidden status. Uses data from both grade item and grade.
* @return boolean true if hidden, false if not
*/
function is_hidden() {
$this->load_grade_item();
return $this->hidden == 1 or ($this->hidden != 0 and $this->hidden > time()) or $this->grade_item->is_hidden();
}
/**
* Check grade hidden status. Uses data from both grade item and grade.
* @return int 0 means visible, 1 hidden always, timestamp hidden until
*/
function get_hidden() {
$this->load_grade_item();
$item_hidden = $this->grade_item->get_hidden();
if ($item_hidden == 1) {
return 1;
} else if ($item_hidden == 0) {
return $this->hidden;
} else {
if ($this->hidden == 0) {
return $item_hidden;
} else if ($this->hidden == 1) {
return 1;
} else if ($this->hidden > $item_hidden) {
return $this->hidden;
} else {
return $item_hidden;
}
}
}
/**
* Set the hidden status of grade, 0 mean visible, 1 always hidden, number means date to hide until.
* @param boolean $cascade ignored
* @param int $hidden new hidden status
*/
function set_hidden($hidden, $cascade=false) {
$this->hidden = $hidden;
$this->update();
}
/**
* Finds and returns a grade_grade instance based on params.
* @static
*
* @param array $params associative arrays varname=>value
* @return object grade_grade instance or false if none found.
*/
function fetch($params) {
return grade_object::fetch_helper('grade_grades', 'grade_grade', $params);
}
/**
* Finds and returns all grade_grade instances based on params.
* @static
*
* @param array $params associative arrays varname=>value
* @return array array of grade_grade insatnces or false if none found.
*/
function fetch_all($params) {
return grade_object::fetch_all_helper('grade_grades', 'grade_grade', $params);
}
/**
* 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 :-)
*
* @static
* @param float $rawgrade
* @param float $source_min
* @param float $source_max
* @param float $target_min
* @param float $target_max
* @return float Converted value
*/
function standardise_score($rawgrade, $source_min, $source_max, $target_min, $target_max) {
if (is_null($rawgrade)) {
return null;
}
$factor = ($rawgrade - $source_min) / ($source_max - $source_min);
$diff = $target_max - $target_min;
$standardised_value = $factor * $diff + $target_min;
return $standardised_value;
}
}
?>