/**
* For a given question in an attempt we walk the complete history of states
* and recalculate the grades as we go along.
*
* This is used when a question is changed and old student
* responses need to be marked with the new version of a question.
*
* TODO: Make sure this is not quiz-specific
*
* @return boolean Indicates whether the grade has changed
* @param object $question A question object
* @param object $attempt The attempt, in which the question needs to be regraded.
* @param object $cmoptions
* @param boolean $verbose Optional. Whether to print progress information or not.
* @param boolean $dryrun Optional. Whether to make changes to grades records
* or record that changes need to be made for a later regrade.
*/
function regrade_question_in_attempt($question, $attempt, $cmoptions, $verbose = false, $dryrun = false)
{
global $DB;
// load all states for this question in this attempt, ordered in sequence
if ($states = $DB->get_records('question_states', array('attempt' => $attempt->uniqueid, 'question' => $question->id), 'seq_number ASC')) {
$states = array_values($states);
// Subtract the grade for the latest state from $attempt->sumgrades to get the
// sumgrades for the attempt without this question.
$attempt->sumgrades -= $states[count($states) - 1]->grade;
// Initialise the replaystate
$replaystate = question_load_specific_state($question, $cmoptions, $attempt, $states[0]->id);
$replaystate->sumpenalty = 0;
$replaystate->last_graded->sumpenalty = 0;
$changed = false;
for ($j = 1; $j < count($states); $j++) {
restore_question_state($question, $states[$j]);
$action = new stdClass();
$action->responses = $states[$j]->responses;
$action->timestamp = $states[$j]->timestamp;
// Change event to submit so that it will be reprocessed
if (in_array($states[$j]->event, array(QUESTION_EVENTCLOSE, QUESTION_EVENTGRADE, QUESTION_EVENTCLOSEANDGRADE))) {
$action->event = QUESTION_EVENTSUBMIT;
// By default take the event that was saved in the database
} else {
$action->event = $states[$j]->event;
}
if ($action->event == QUESTION_EVENTMANUALGRADE) {
// Ensure that the grade is in range - in the past this was not checked,
// but now it is (MDL-14835) - so we need to ensure the data is valid before
// proceeding.
if ($states[$j]->grade < 0) {
$states[$j]->grade = 0;
$changed = true;
} else {
if ($states[$j]->grade > $question->maxgrade) {
$states[$j]->grade = $question->maxgrade;
$changed = true;
}
}
if (!$dryrun) {
$error = question_process_comment($question, $replaystate, $attempt, $replaystate->manualcomment, $states[$j]->grade);
if (is_string($error)) {
notify($error);
}
} else {
$replaystate->grade = $states[$j]->grade;
}
} else {
// Reprocess (regrade) responses
if (!question_process_responses($question, $replaystate, $action, $cmoptions, $attempt) && $verbose) {
$a = new stdClass();
$a->qid = $question->id;
$a->stateid = $states[$j]->id;
notify(get_string('errorduringregrade', 'question', $a));
}
// We need rounding here because grades in the DB get truncated
// e.g. 0.33333 != 0.3333333, but we want them to be equal here
if (round((double) $replaystate->raw_grade, 5) != round((double) $states[$j]->raw_grade, 5) or round((double) $replaystate->penalty, 5) != round((double) $states[$j]->penalty, 5) or round((double) $replaystate->grade, 5) != round((double) $states[$j]->grade, 5)) {
$changed = true;
}
// If this was previously a closed state, and it has been knoced back to
// graded, then fix up the state again.
if ($replaystate->event == QUESTION_EVENTGRADE && ($states[$j]->event == QUESTION_EVENTCLOSE || $states[$j]->event == QUESTION_EVENTCLOSEANDGRADE)) {
$replaystate->event = $states[$j]->event;
}
}
$replaystate->id = $states[$j]->id;
$replaystate->changed = true;
$replaystate->update = true;
// This will ensure that the existing database entry is updated rather than a new one created
if (!$dryrun) {
save_question_session($question, $replaystate);
}
}
if ($changed) {
if (!$dryrun) {
// TODO, call a method in quiz to do this, where 'quiz' comes from
// the question_attempts table.
$DB->update_record('quiz_attempts', $attempt);
}
}
if ($changed) {
$toinsert = new object();
$toinsert->oldgrade = round((double) $states[count($states) - 1]->grade, 5);
$toinsert->newgrade = round((double) $replaystate->grade, 5);
$toinsert->attemptid = $attempt->uniqueid;
$toinsert->questionid = $question->id;
//the grade saved is the old grade if the new grade is saved
//it is the new grade if this is a dry run.
$toinsert->regraded = $dryrun ? 0 : 1;
$toinsert->timemodified = time();
$DB->insert_record('quiz_question_regrade', $toinsert);
return true;
} else {
return false;
}
}
return false;
}
/**
* Load a particular state of a particular question. Used by the reviewquestion.php
* script to let the teacher walk through the entire sequence of a student's
* interaction with a question.
*
* @param $questionid the question id
* @param $stateid the id of the particular state to load.
*/
public function load_specific_question_state($questionid, $stateid)
{
global $DB;
$state = question_load_specific_state($this->questions[$questionid], $this->quiz, $this->attempt, $stateid);
if ($state === false) {
throw new moodle_quiz_exception($this, 'invalidstateid');
}
$this->states[$questionid] = $state;
}
