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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/>.
/**
* Common classes used by gradingform plugintypes are defined here
*
* @package core_grading
* @copyright 2011 David Mudrak <david@moodle.com>
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
defined('MOODLE_INTERNAL') || die();
/**
* Class represents a grading form definition used in a particular area
*
* General data about definition is stored in the standard DB table
* grading_definitions. A separate entry is created for each grading area
* (i.e. for each module). Plugins may define and use additional tables
* to store additional data about definitions.
*
* Advanced grading plugins must declare a class gradingform_xxxx_controller
* extending this class and put it in lib.php in the plugin folder.
*
* See {@link gradingform_rubric_controller} as an example
*
* Except for overwriting abstract functions, plugin developers may want
* to overwrite functions responsible for loading and saving of the
* definition to include additional data stored.
*
* @package core_grading
* @copyright 2011 David Mudrak <david@moodle.com>
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
* @category grading
*/
abstract class gradingform_controller {
/** undefined definition status */
const DEFINITION_STATUS_NULL = 0;
/** the form is currently being edited and is not ready for usage yet */
const DEFINITION_STATUS_DRAFT = 10;
/** the form was marked as ready for actual usage */
const DEFINITION_STATUS_READY = 20;
/** @var stdClass the context */
protected $context;
/** @var string the frankenstyle name of the component */
protected $component;
/** @var string the name of the gradable area */
protected $area;
/** @var int the id of the gradable area record */
protected $areaid;
/** @var stdClass|false the definition structure */
protected $definition = false;
/** @var array graderange array of valid grades for this area. Use set_grade_range and get_grade_range to access this */
private $graderange = null;
/** @var bool if decimal values are allowed as grades. */
private $allowgradedecimals = false;
/** @var boolean|null cached result of function has_active_instances() */
protected $hasactiveinstances = null;
/**
* Do not instantinate this directly, use {@link grading_manager::get_controller()}
*
* @param stdClass $context the context of the form
* @param string $component the frankenstyle name of the component
* @param string $area the name of the gradable area
* @param int $areaid the id of the gradable area record
*/
public function __construct(stdClass $context, $component, $area, $areaid) {
global $DB;
$this->context = $context;
list($type, $name) = core_component::normalize_component($component);
$this->component = $type.'_'.$name;
$this->area = $area;
$this->areaid = $areaid;
$this->load_definition();
}
/**
* Returns controller context
*
* @return stdClass controller context
*/
public function get_context() {
return $this->context;
}
/**
* Returns gradable component name
*
* @return string gradable component name
*/
public function get_component() {
return $this->component;
}
/**
* Returns gradable area name
*
* @return string gradable area name
*/
public function get_area() {
return $this->area;
}
/**
* Returns gradable area id
*
* @return int gradable area id
*/
public function get_areaid() {
return $this->areaid;
}
/**
* Is the form definition record available?
*
* Note that this actually checks whether the process of defining the form ever started
* and not whether the form definition should be considered as final.
*
* @return boolean
*/
public function is_form_defined() {
return ($this->definition !== false);
}
/**
* Is the grading form defined and ready for usage?
*
* @return boolean
*/
public function is_form_available() {
return ($this->is_form_defined() && $this->definition->status == self::DEFINITION_STATUS_READY);
}
/**
* Is the grading form saved as a shared public template?
*
* @return boolean
*/
public function is_shared_template() {
return ($this->get_context()->id == context_system::instance()->id
and $this->get_component() == 'core_grading');
}
/**
* Is the grading form owned by the given user?
*
* The form owner is the user who created this instance of the form.
*
* @param int $userid the user id to check, defaults to the current user
* @return boolean|null null if the form not defined yet, boolean otherwise
*/
public function is_own_form($userid = null) {
global $USER;
if (!$this->is_form_defined()) {
return null;
}
if (is_null($userid)) {
$userid = $USER->id;
}
return ($this->definition->usercreated == $userid);
}
/**
* Returns a message why this form is unavailable. Maybe overriden by plugins to give more details.
* @see is_form_available()
*
* @return string
*/
public function form_unavailable_notification() {
if ($this->is_form_available()) {
return null;
}
return get_string('gradingformunavailable', 'grading');
}
/**
* Returns URL of a page where the grading form can be defined and edited.
*
* @param moodle_url $returnurl optional URL of a page where the user should be sent once they are finished with editing
* @return moodle_url
*/
public function get_editor_url(moodle_url $returnurl = null) {
$params = array('areaid' => $this->areaid);
if (!is_null($returnurl)) {
$params['returnurl'] = $returnurl->out(false);
}
return new moodle_url('/grade/grading/form/'.$this->get_method_name().'/edit.php', $params);
}
/**
* Extends the module settings navigation
*
* This function is called when the context for the page is an activity module with the
* FEATURE_ADVANCED_GRADING, the user has the permission moodle/grade:managegradingforms
* and there is an area with the active grading method set to the given plugin.
*
* @param settings_navigation $settingsnav {@link settings_navigation}
* @param navigation_node $node {@link navigation_node}
*/
public function extend_settings_navigation(settings_navigation $settingsnav, navigation_node $node=null) {
// do not extend by default
}
/**
* Extends the module navigation
*
* This function is called when the context for the page is an activity module with the
* FEATURE_ADVANCED_GRADING and there is an area with the active grading method set to the given plugin.
*
* @param global_navigation $navigation {@link global_navigation}
* @param navigation_node $node {@link navigation_node}
*/
public function extend_navigation(global_navigation $navigation, navigation_node $node=null) {
// do not extend by default
}
/**
* Returns the grading form definition structure
*
* @param boolean $force whether to force loading from DB even if it was already loaded
* @return stdClass|false definition data or false if the form is not defined yet
*/
public function get_definition($force = false) {
if ($this->definition === false || $force) {
$this->load_definition();
}
return $this->definition;
}
/**
* Returns the form definition suitable for cloning into another area
*
* @param gradingform_controller $target the controller of the new copy
* @return stdClass definition structure to pass to the target's {@link update_definition()}
*/
public function get_definition_copy(gradingform_controller $target) {
if (get_class($this) != get_class($target)) {
throw new coding_exception('The source and copy controller mismatch');
}
if ($target->is_form_defined()) {
throw new coding_exception('The target controller already contains a form definition');
}
$old = $this->get_definition();
// keep our id
$new = new stdClass();
$new->copiedfromid = $old->id;
$new->name = $old->name;
// once we support files embedded into the description, we will want to
// relink them into the new file area here (that is why we accept $target)
$new->description = $old->description;
$new->descriptionformat = $old->descriptionformat;
$new->options = $old->options;
$new->status = $old->status;
return $new;
}
/**
* Saves the defintion data into the database
*
* The implementation in this base class stores the common data into the record
* into the {grading_definition} table. The plugins are likely to extend this
* and save their data into own tables, too.
*
* @param stdClass $definition data containing values for the {grading_definition} table
* @param int|null $usermodified optional userid of the author of the definition, defaults to the current user
*/
public function update_definition(stdClass $definition, $usermodified = null) {
global $DB, $USER;
if (is_null($usermodified)) {
$usermodified = $USER->id;
}
if (!empty($this->definition->id)) {
// prepare a record to be updated
$record = new stdClass();
// populate it with scalar values from the passed definition structure
foreach ($definition as $prop => $val) {
if (is_array($val) or is_object($val)) {
// probably plugin's data
continue;
}
$record->{$prop} = $val;
}
// make sure we do not override some crucial values by accident
if (!empty($record->id) and $record->id != $this->definition->id) {
throw new coding_exception('Attempting to update other definition record.');
}
$record->id = $this->definition->id;
unset($record->areaid);
unset($record->method);
unset($record->timecreated);
// set the modification flags
$record->timemodified = time();
$record->usermodified = $usermodified;
$DB->update_record('grading_definitions', $record);
} else if ($this->definition === false) {
// prepare a record to be inserted
$record = new stdClass();
// populate it with scalar values from the passed definition structure
foreach ($definition as $prop => $val) {
if (is_array($val) or is_object($val)) {
// probably plugin's data
continue;
}
$record->{$prop} = $val;
}
// make sure we do not override some crucial values by accident
if (!empty($record->id)) {
throw new coding_exception('Attempting to create a new record while there is already one existing.');
}
unset($record->id);
$record->areaid = $this->areaid;
$record->method = $this->get_method_name();
$record->timecreated = time();
$record->usercreated = $usermodified;
$record->timemodified = $record->timecreated;
$record->usermodified = $record->usercreated;
if (empty($record->status)) {
$record->status = self::DEFINITION_STATUS_DRAFT;
}
if (empty($record->descriptionformat)) {
$record->descriptionformat = FORMAT_MOODLE; // field can not be empty
}
$DB->insert_record('grading_definitions', $record);
} else {
throw new coding_exception('Unknown status of the cached definition record.');
}
}
/**
* Formats the definition description for display on page
*
* @return string
*/
public function get_formatted_description() {
if (!isset($this->definition->description)) {
return '';
}
return format_text($this->definition->description, $this->definition->descriptionformat);
}
/**
* Returns the current instance (either with status ACTIVE or NEEDUPDATE) for this definition for the
* specified $raterid and $itemid (if multiple raters are allowed, or only for $itemid otherwise).
*
* @param int $raterid
* @param int $itemid
* @param boolean $idonly
* @return mixed if $idonly=true returns id of the found instance, otherwise returns the instance object
*/
public function get_current_instance($raterid, $itemid, $idonly = false) {
global $DB;
$params = array(
'definitionid' => $this->definition->id,
'itemid' => $itemid,
'status1' => gradingform_instance::INSTANCE_STATUS_ACTIVE,
'status2' => gradingform_instance::INSTANCE_STATUS_NEEDUPDATE);
$select = 'definitionid=:definitionid and itemid=:itemid and (status=:status1 or status=:status2)';
if (false) {
// TODO MDL-31237 should be: if ($manager->allow_multiple_raters())
$select .= ' and raterid=:raterid';
$params['raterid'] = $raterid;
}
if ($idonly) {
if ($current = $DB->get_record_select('grading_instances', $select, $params, 'id', IGNORE_MISSING)) {
return $current->id;
}
} else {
if ($current = $DB->get_record_select('grading_instances', $select, $params, '*', IGNORE_MISSING)) {
return $this->get_instance($current);
}
}
return null;
}
/**
* Returns list of ACTIVE instances for the specified $itemid
* (intentionally does not return instances with status NEEDUPDATE)
*
* @param int $itemid
* @return array of gradingform_instance objects
*/
public function get_active_instances($itemid) {
global $DB;
$conditions = array('definitionid' => $this->definition->id,
'itemid' => $itemid,
'status' => gradingform_instance::INSTANCE_STATUS_ACTIVE);
$records = $DB->get_recordset('grading_instances', $conditions);
$rv = array();
foreach ($records as $record) {
$rv[] = $this->get_instance($record);
}
$records->close();
return $rv;
}
/**
* Returns an array of all active instances for this definition.
* (intentionally does not return instances with status NEEDUPDATE)
*
* @param int since only return instances with timemodified >= since
* @return array of gradingform_instance objects
*/
public function get_all_active_instances($since = 0) {
global $DB;
$conditions = array ($this->definition->id,
gradingform_instance::INSTANCE_STATUS_ACTIVE,
$since);
$where = "definitionid = ? AND status = ? AND timemodified >= ?";
$records = $DB->get_records_select('grading_instances', $where, $conditions);
$rv = array();
foreach ($records as $record) {
$rv[] = $this->get_instance($record);
}
return $rv;
}
/**
* Returns true if there are already people who has been graded on this definition.
* In this case plugins may restrict changes of the grading definition
*
* @return boolean
*/
public function has_active_instances() {
global $DB;
if (empty($this->definition->id)) {
return false;
}
if ($this->hasactiveinstances === null) {
$conditions = array('definitionid' => $this->definition->id,
'status' => gradingform_instance::INSTANCE_STATUS_ACTIVE);
$this->hasactiveinstances = $DB->record_exists('grading_instances', $conditions);
}
return $this->hasactiveinstances;
}
/**
* Returns the object of type gradingform_XXX_instance (where XXX is the plugin method name)
*
* @param mixed $instance id or row from grading_isntances table
* @return gradingform_instance
*/
protected function get_instance($instance) {
global $DB;
if (is_scalar($instance)) {
// instance id is passed as parameter
$instance = $DB->get_record('grading_instances', array('id' => $instance), '*', MUST_EXIST);
}
if ($instance) {
$class = 'gradingform_'. $this->get_method_name(). '_instance';
return new $class($this, $instance);
}
return null;
}
/**
* This function is invoked when user (teacher) starts grading.
* It creates and returns copy of the current ACTIVE instance if it exists. If this is the
* first grading attempt, a new instance is created.
* The status of the returned instance is INCOMPLETE
*
* @param int $raterid
* @param int $itemid
* @return gradingform_instance
*/
public function create_instance($raterid, $itemid = null) {
// first find if there is already an active instance for this itemid
if ($itemid && $current = $this->get_current_instance($raterid, $itemid)) {
return $this->get_instance($current->copy($raterid, $itemid));
} else {
$class = 'gradingform_'. $this->get_method_name(). '_instance';
return $this->get_instance($class::create_new($this->definition->id, $raterid, $itemid));
}
}
/**
* If instanceid is specified and grading instance exists and it is created by this rater for
* this item, this instance is returned.
* Otherwise new instance is created for the specified rater and itemid
*
* @param int $instanceid
* @param int $raterid
* @param int $itemid
* @return gradingform_instance
*/
public function get_or_create_instance($instanceid, $raterid, $itemid) {
global $DB;
if ($instanceid &&
$instance = $DB->get_record('grading_instances', array('id' => $instanceid, 'raterid' => $raterid, 'itemid' => $itemid), '*', IGNORE_MISSING)) {
return $this->get_instance($instance);
}
return $this->create_instance($raterid, $itemid);
}
/**
* Returns the HTML code displaying the preview of the grading form
*
* Plugins are forced to override this. Ideally they should delegate
* the task to their own renderer.
*
* @param moodle_page $page the target page
* @return string
*/
abstract public function render_preview(moodle_page $page);
/**
* Deletes the form definition and all the associated data
*
* @see delete_plugin_definition()
* @return void
*/
public function delete_definition() {
global $DB;
if (!$this->is_form_defined()) {
// nothing to do
return;
}
// firstly, let the plugin delete everything from their own tables
$this->delete_plugin_definition();
// then, delete all instances left
$DB->delete_records('grading_instances', array('definitionid' => $this->definition->id));
// finally, delete the main definition record
$DB->delete_records('grading_definitions', array('id' => $this->definition->id));
$this->definition = false;
}
/**
* Prepare the part of the search query to append to the FROM statement
*
* @param string $gdid the alias of grading_definitions.id column used by the caller
* @return string
*/
public static function sql_search_from_tables($gdid) {
return '';
}
/**
* Prepare the parts of the SQL WHERE statement to search for the given token
*
* The returned array cosists of the list of SQL comparions and the list of
* respective parameters for the comparisons. The returned chunks will be joined
* with other conditions using the OR operator.
*
* @param string $token token to search for
* @return array
*/
public static function sql_search_where($token) {
$subsql = array();
$params = array();
return array($subsql, $params);
}
// //////////////////////////////////////////////////////////////////////////
/**
* Loads the form definition if it exists
*
* The default implementation just tries to load the record from the {grading_definitions}
* table. The plugins are likely to override this with a more complex query that loads
* all required data at once.
*/
protected function load_definition() {
global $DB;
$this->definition = $DB->get_record('grading_definitions', array(
'areaid' => $this->areaid,
'method' => $this->get_method_name()), '*', IGNORE_MISSING);
}
/**
* Deletes all plugin data associated with the given form definiton
*
* @see delete_definition()
*/
abstract protected function delete_plugin_definition();
/**
* Returns the name of the grading method plugin, eg 'rubric'
*
* @return string the name of the grading method plugin, eg 'rubric'
* @see PARAM_PLUGIN
*/
protected function get_method_name() {
if (preg_match('/^gradingform_([a-z][a-z0-9_]*[a-z0-9])_controller$/', get_class($this), $matches)) {
return $matches[1];
} else {
throw new coding_exception('Invalid class name');
}
}
/**
* Returns html code to be included in student's feedback.
*
* @param moodle_page $page
* @param int $itemid
* @param array $gradinginfo result of function grade_get_grades if plugin want to use some of their info
* @param string $defaultcontent default string to be returned if no active grading is found or for some reason can not be shown to a user
* @param boolean $cangrade whether current user has capability to grade in this context
* @return string
*/
public function render_grade($page, $itemid, $gradinginfo, $defaultcontent, $cangrade) {
return $defaultcontent;
}
/**
* Sets the range of grades used in this area. This is usually either range like 0-100
* or the scale where keys start from 1.
*
* Typically modules will call it:
* $controller->set_grade_range(make_grades_menu($gradingtype), $gradingtype > 0);
* Negative $gradingtype means that scale is used and the grade must be rounded
* to the nearest int. Positive $gradingtype means that range 0..$gradingtype
* is used for the grades and in this case grade does not have to be rounded.
*
* Sometimes modules always expect grade to be rounded (like mod_assignment does).
*
* @param array $graderange array where first _key_ is the minimum grade and the
* last key is the maximum grade.
* @param bool $allowgradedecimals if decimal values are allowed as grades.
*/
public final function set_grade_range(array $graderange, $allowgradedecimals = false) {
$this->graderange = $graderange;
$this->allowgradedecimals = $allowgradedecimals;
}
/**
* Returns the range of grades used in this area
*
* @return array
*/
public final function get_grade_range() {
if (empty($this->graderange)) {
return array();
}
return $this->graderange;
}
/**
* Returns if decimal values are allowed as grades
*
* @return bool
*/
public final function get_allow_grade_decimals() {
return $this->allowgradedecimals;
}
/**
* Overridden by sub classes that wish to make definition details available to web services.
* When not overridden, only definition data common to all grading methods is made available.
* When overriding, the return value should be an array containing one or more key/value pairs.
* These key/value pairs should match the definition returned by the get_definition() function.
* For examples, look at:
* $gradingform_rubric_controller->get_external_definition_details()
* $gradingform_guide_controller->get_external_definition_details()
* @return array An array of one or more key/value pairs containing the external_multiple_structure/s
* corresponding to the definition returned by $controller->get_definition()
* @since Moodle 2.5
*/
public static function get_external_definition_details() {
return null;
}
/**
* Overridden by sub classes that wish to make instance filling details available to web services.
* When not overridden, only instance filling data common to all grading methods is made available.
* When overriding, the return value should be an array containing one or more key/value pairs.
* These key/value pairs should match the filling data returned by the get_<method>_filling() function
* in the gradingform_instance subclass.
* For examples, look at:
* $gradingform_rubric_controller->get_external_instance_filling_details()
* $gradingform_guide_controller->get_external_instance_filling_details()
*
* @return array An array of one or more key/value pairs containing the external_multiple_structure/s
* corresponding to the definition returned by $gradingform_<method>_instance->get_<method>_filling()
* @since Moodle 2.6
*/
public static function get_external_instance_filling_details() {
return null;
}
}
/**
* Class to manage one gradingform instance.
*
* Gradingform instance is created for each evaluation of a student, using advanced grading.
* It is stored as an entry in the DB table gradingform_instance.
*
* One instance (usually the latest) has the status INSTANCE_STATUS_ACTIVE. Sometimes it may
* happen that a teacher wants to change the definition when some students have already been
* graded. In this case their instances change status to INSTANCE_STATUS_NEEDUPDATE.
*
* To support future use of AJAX for background saving of incomplete evaluations the
* status INSTANCE_STATUS_INCOMPLETE is introduced. If 'Cancel' is pressed this entry
* is deleted.
* When grade is updated the previous active instance receives status INSTANCE_STATUS_ACTIVE.
*
* Advanced grading plugins must declare a class gradingform_xxxx_instance
* extending this class and put it in lib.php in the plugin folder.
*
* The reference to an instance of this class is passed to an advanced grading form element
* included in the grading form, so this class must implement functions for rendering
* and validation of this form element. See {@link MoodleQuickForm_grading}
*
* @package core_grading
* @copyright 2011 Marina Glancy
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
* @category grading
*/
abstract class gradingform_instance {
/** Valid istance status */
const INSTANCE_STATUS_ACTIVE = 1;
/** The grade needs to be updated by grader (usually because of changes is grading method) */
const INSTANCE_STATUS_NEEDUPDATE = 2;
/** The grader started grading but did clicked neither submit nor cancel */
const INSTANCE_STATUS_INCOMPLETE = 0;
/** Grader re-graded the student and this is the status for previous grade stored as history */
const INSTANCE_STATUS_ARCHIVE = 3;
/** @var stdClass record from table grading_instances */
protected $data;
/** @var gradingform_controller link to the corresponding controller */
protected $controller;
/**
* Creates an instance
*
* @param gradingform_controller $controller
* @param stdClass $data
*/
public function __construct($controller, $data) {
$this->data = (object)$data;
$this->controller = $controller;
}
/**
* Creates a new empty instance in DB and mark its status as INCOMPLETE
*
* @param int $definitionid
* @param int $raterid
* @param int $itemid
* @return int id of the created instance
*/
public static function create_new($definitionid, $raterid, $itemid) {
global $DB;
$instance = new stdClass();
$instance->definitionid = $definitionid;
$instance->raterid = $raterid;
$instance->itemid = $itemid;
$instance->status = self::INSTANCE_STATUS_INCOMPLETE;
$instance->timemodified = time();
$instance->feedbackformat = FORMAT_MOODLE;
$instanceid = $DB->insert_record('grading_instances', $instance);
return $instanceid;
}
/**
* Duplicates the instance before editing (optionally substitutes raterid and/or itemid with
* the specified values)
* Plugins may want to override this function to copy data from additional tables as well
*
* @param int $raterid value for raterid in the duplicate
* @param int $itemid value for itemid in the duplicate
* @return int id of the new instance
*/
public function copy($raterid, $itemid) {
global $DB;
$data = (array)$this->data; // Cast to array to make a copy
unset($data['id']);
$data['raterid'] = $raterid;
$data['itemid'] = $itemid;
$data['timemodified'] = time();
$data['status'] = self::INSTANCE_STATUS_INCOMPLETE;
$instanceid = $DB->insert_record('grading_instances', $data);
return $instanceid;
}
/**
* Returns the current (active or needupdate) instance for the same raterid and itemid as this
* instance. This function is useful to find the status of the currently modified instance
*
* @return gradingform_instance
*/
public function get_current_instance() {
if ($this->get_status() == self::INSTANCE_STATUS_ACTIVE || $this->get_status() == self::INSTANCE_STATUS_NEEDUPDATE) {
return $this;
}
return $this->get_controller()->get_current_instance($this->data->raterid, $this->data->itemid);
}
/**
* Returns the controller
*
* @return gradingform_controller
*/
public function get_controller() {
return $this->controller;
}
/**
* Returns the specified element from object $this->data
*
* @param string $key
* @return mixed
*/
public function get_data($key) {
if (isset($this->data->$key)) {
return $this->data->$key;
}
return null;
}
/**
* Returns instance id
*
* @return int
*/
public function get_id() {
return $this->get_data('id');
}
/**
* Returns instance status
*
* @return int
*/
public function get_status() {
return $this->get_data('status');
}
/**
* Marks the instance as ACTIVE and current active instance (if exists) as ARCHIVE
*/
protected function make_active() {
global $DB;
if ($this->data->status == self::INSTANCE_STATUS_ACTIVE) {
// already active
return;
}
if (empty($this->data->itemid)) {
throw new coding_exception('You cannot mark active the grading instance without itemid');
}
$currentid = $this->get_controller()->get_current_instance($this->data->raterid, $this->data->itemid, true);
if ($currentid && $currentid != $this->get_id()) {
$DB->update_record('grading_instances', array('id' => $currentid, 'status' => self::INSTANCE_STATUS_ARCHIVE));
}
$DB->update_record('grading_instances', array('id' => $this->get_id(), 'status' => self::INSTANCE_STATUS_ACTIVE));
$this->data->status = self::INSTANCE_STATUS_ACTIVE;
}
/**
* Deletes this (INCOMPLETE) instance from database. This function is invoked on cancelling the
* grading form and/or during cron cleanup.
* Plugins using additional tables must override this method to remove additional data.
* Note that if the teacher just closes the window or presses 'Back' button of the browser,
* this function is not invoked.
*/
public function cancel() {
global $DB;
// TODO MDL-31239 throw exception if status is not INSTANCE_STATUS_INCOMPLETE
$DB->delete_records('grading_instances', array('id' => $this->get_id()));
}
/**
* Updates the instance with the data received from grading form. This function may be
* called via AJAX when grading is not yet completed, so it does not change the
* status of the instance.
*
* @param array $elementvalue
*/
public function update($elementvalue) {
global $DB;
$newdata = new stdClass();
$newdata->id = $this->get_id();
$newdata->timemodified = time();
if (isset($elementvalue['itemid']) && $elementvalue['itemid'] != $this->data->itemid) {
$newdata->itemid = $elementvalue['itemid'];
}
// TODO MDL-31087 also update: rawgrade, feedback, feedbackformat
$DB->update_record('grading_instances', $newdata);
foreach ($newdata as $key => $value) {
$this->data->$key = $value;
}
}
/**
* Calculates the grade to be pushed to the gradebook
*
* Returned grade must be in range $this->get_controller()->get_grade_range()
* Plugins must returned grade converted to int unless
* $this->get_controller()->get_allow_grade_decimals() is true.
*
* @return float|int
*/
abstract public function get_grade();
/**
* Determines whether the submitted form was empty.
*
* @param array $elementvalue value of element submitted from the form
* @return boolean true if the form is empty
*/
public function is_empty_form($elementvalue) {
return false;
}
/**
* Removes the attempt from the gradingform_*_fillings table.
* This function is not abstract as to not break plugins that might
* use advanced grading.
* @param array $data the attempt data
*/
public function clear_attempt($data) {
// This function is empty because the way to clear a grade
// attempt will be different depending on the grading method.
return;
}
/**
* Called when teacher submits the grading form:
* updates the instance in DB, marks it as ACTIVE and returns the grade to be pushed to the gradebook.
* $itemid must be specified here (it was not required when the instance was
* created, because it might not existed in draft)
*
* @param array $elementvalue
* @param int $itemid
* @return int the grade on 0-100 scale
*/
public function submit_and_get_grade($elementvalue, $itemid) {
$elementvalue['itemid'] = $itemid;
if ($this->is_empty_form($elementvalue)) {
$this->clear_attempt($elementvalue);
$this->make_active();
return -1;
}
$this->update($elementvalue);
$this->make_active();
return $this->get_grade();
}
/**
* Returns html for form element of type 'grading'. If there is a form input element
* it must have the name $gradingformelement->getName().
* If there are more than one input elements they MUST be elements of array with
* name $gradingformelement->getName().
* Example: {NAME}[myelement1], {NAME}[myelement2][sub1], {NAME}[myelement2][sub2], etc.
* ( {NAME} is a shortcut for $gradingformelement->getName() )
* After submitting the form the value of $_POST[{NAME}] is passed to the functions
* validate_grading_element() and submit_and_get_grade()
*
* Plugins may use $gradingformelement->getValue() to get the value passed on previous
* form submit
*
* When forming html it is a plugin's responsibility to analyze flags
* $gradingformelement->_flagFrozen and $gradingformelement->_persistantFreeze:
*
* (_flagFrozen == false) => form element is editable
*
* (_flagFrozen == false && _persistantFreeze == true) => form element is not editable
* but all values are passed as hidden elements
*
* (_flagFrozen == false && _persistantFreeze == false) => form element is not editable
* and no values are passed as hidden elements
*
* Plugins are welcome to use AJAX in the form element. But it is strongly recommended
* that the grading only becomes active when teacher presses 'Submit' button (the
* method submit_and_get_grade() is invoked)
*
* Also client-side JS validation may be implemented here
*
* @see MoodleQuickForm_grading in lib/form/grading.php
*
* @param moodle_page $page
* @param MoodleQuickForm_grading $gradingformelement
* @return string
*/
abstract function render_grading_element($page, $gradingformelement);
/**
* Server-side validation of the data received from grading form.
*
* @param mixed $elementvalue is the scalar or array received in $_POST
* @return boolean true if the form data is validated and contains no errors
*/
public function validate_grading_element($elementvalue) {
return true;
}
/**
* Returns the error message displayed if validation failed.
* If plugin wants to display custom message, the empty string should be returned here
* and the custom message should be output in render_grading_element()
*
* Please note that in assignments grading in 2.2 the grading form is not validated
* properly and this message is not being displayed.
*
* @see validate_grading_element()
* @return string
*/
public function default_validation_error_message() {
return '';
}
}