mirrored from git://git.moodle.org/moodle.git
/
report.php
655 lines (571 loc) · 26.7 KB
/
report.php
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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 the quiz overview report class.
*
* @package quiz_overview
* @copyright 1999 onwards Martin Dougiamas and others {@link http://moodle.com}
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
defined('MOODLE_INTERNAL') || die();
require_once($CFG->dirroot . '/mod/quiz/report/attemptsreport.php');
require_once($CFG->dirroot . '/mod/quiz/report/overview/overview_options.php');
require_once($CFG->dirroot . '/mod/quiz/report/overview/overview_form.php');
require_once($CFG->dirroot . '/mod/quiz/report/overview/overview_table.php');
/**
* Quiz report subclass for the overview (grades) report.
*
* @copyright 1999 onwards Martin Dougiamas and others {@link http://moodle.com}
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
class quiz_overview_report extends quiz_attempts_report {
public function display($quiz, $cm, $course) {
global $DB, $OUTPUT, $PAGE;
list($currentgroup, $studentsjoins, $groupstudentsjoins, $allowedjoins) = $this->init(
'overview', 'quiz_overview_settings_form', $quiz, $cm, $course);
$options = new quiz_overview_options('overview', $quiz, $cm, $course);
if ($fromform = $this->form->get_data()) {
$options->process_settings_from_form($fromform);
} else {
$options->process_settings_from_params();
}
$this->form->set_data($options->get_initial_form_data());
// Load the required questions.
$questions = quiz_report_get_significant_questions($quiz);
// Prepare for downloading, if applicable.
$courseshortname = format_string($course->shortname, true,
array('context' => context_course::instance($course->id)));
$table = new quiz_overview_table($quiz, $this->context, $this->qmsubselect,
$options, $groupstudentsjoins, $studentsjoins, $questions, $options->get_url());
$filename = quiz_report_download_filename(get_string('overviewfilename', 'quiz_overview'),
$courseshortname, $quiz->name);
$table->is_downloading($options->download, $filename,
$courseshortname . ' ' . format_string($quiz->name, true));
if ($table->is_downloading()) {
raise_memory_limit(MEMORY_EXTRA);
}
$this->hasgroupstudents = false;
if (!empty($groupstudentsjoins->joins)) {
$sql = "SELECT DISTINCT u.id
FROM {user} u
$groupstudentsjoins->joins
WHERE $groupstudentsjoins->wheres";
$this->hasgroupstudents = $DB->record_exists_sql($sql, $groupstudentsjoins->params);
}
$hasstudents = false;
if (!empty($studentsjoins->joins)) {
$sql = "SELECT DISTINCT u.id
FROM {user} u
$studentsjoins->joins
WHERE $studentsjoins->wheres";
$hasstudents = $DB->record_exists_sql($sql, $studentsjoins->params);
}
if ($options->attempts == self::ALL_WITH) {
// This option is only available to users who can access all groups in
// groups mode, so setting allowed to empty (which means all quiz attempts
// are accessible, is not a security porblem.
$allowedjoins = new \core\dml\sql_join();
}
$this->course = $course; // Hack to make this available in process_actions.
$this->process_actions($quiz, $cm, $currentgroup, $groupstudentsjoins, $allowedjoins, $options->get_url());
// Start output.
if (!$table->is_downloading()) {
// Only print headers if not asked to download data.
$this->print_header_and_tabs($cm, $course, $quiz, $this->mode);
}
if ($groupmode = groups_get_activity_groupmode($cm)) {
// Groups are being used, so output the group selector if we are not downloading.
if (!$table->is_downloading()) {
groups_print_activity_menu($cm, $options->get_url());
}
}
// Print information on the number of existing attempts.
if (!$table->is_downloading()) {
// Do not print notices when downloading.
if ($strattemptnum = quiz_num_attempt_summary($quiz, $cm, true, $currentgroup)) {
echo '<div class="quizattemptcounts">' . $strattemptnum . '</div>';
}
}
$hasquestions = quiz_has_questions($quiz->id);
if (!$table->is_downloading()) {
if (!$hasquestions) {
echo quiz_no_questions_message($quiz, $cm, $this->context);
} else if (!$hasstudents) {
echo $OUTPUT->notification(get_string('nostudentsyet'));
} else if ($currentgroup && !$this->hasgroupstudents) {
echo $OUTPUT->notification(get_string('nostudentsingroup'));
}
// Print the display options.
$this->form->display();
}
$hasstudents = $hasstudents && (!$currentgroup || $this->hasgroupstudents);
if ($hasquestions && ($hasstudents || $options->attempts == self::ALL_WITH)) {
// Construct the SQL.
$table->setup_sql_queries($allowedjoins);
if (!$table->is_downloading()) {
// Output the regrade buttons.
if (has_capability('mod/quiz:regrade', $this->context)) {
$regradesneeded = $this->count_question_attempts_needing_regrade(
$quiz, $groupstudentsjoins);
if ($currentgroup) {
$a= new stdClass();
$a->groupname = groups_get_group_name($currentgroup);
$a->coursestudents = get_string('participants');
$a->countregradeneeded = $regradesneeded;
$regradealldrydolabel =
get_string('regradealldrydogroup', 'quiz_overview', $a);
$regradealldrylabel =
get_string('regradealldrygroup', 'quiz_overview', $a);
$regradealllabel =
get_string('regradeallgroup', 'quiz_overview', $a);
} else {
$regradealldrydolabel =
get_string('regradealldrydo', 'quiz_overview', $regradesneeded);
$regradealldrylabel =
get_string('regradealldry', 'quiz_overview');
$regradealllabel =
get_string('regradeall', 'quiz_overview');
}
$displayurl = new moodle_url($options->get_url(), array('sesskey' => sesskey()));
echo '<div class="mdl-align">';
echo '<form action="'.$displayurl->out_omit_querystring().'">';
echo '<div>';
echo html_writer::input_hidden_params($displayurl);
echo '<input type="submit" class="btn btn-secondary" name="regradeall" value="'.$regradealllabel.'"/>';
echo '<input type="submit" class="btn btn-secondary m-l-1" name="regradealldry" value="' .
$regradealldrylabel . '"/>';
if ($regradesneeded) {
echo '<input type="submit" class="btn btn-secondary m-l-1" name="regradealldrydo" value="' .
$regradealldrydolabel . '"/>';
}
echo '</div>';
echo '</form>';
echo '</div>';
}
// Print information on the grading method.
if ($strattempthighlight = quiz_report_highlighting_grading_method(
$quiz, $this->qmsubselect, $options->onlygraded)) {
echo '<div class="quizattemptcounts">' . $strattempthighlight . '</div>';
}
}
// Define table columns.
$columns = array();
$headers = array();
if (!$table->is_downloading() && $options->checkboxcolumn) {
$columns[] = 'checkbox';
$headers[] = null;
}
$this->add_user_columns($table, $columns, $headers);
$this->add_state_column($columns, $headers);
$this->add_time_columns($columns, $headers);
$this->add_grade_columns($quiz, $options->usercanseegrades, $columns, $headers, false);
if (!$table->is_downloading() && has_capability('mod/quiz:regrade', $this->context) &&
$this->has_regraded_questions($table->sql->from, $table->sql->where, $table->sql->params)) {
$columns[] = 'regraded';
$headers[] = get_string('regrade', 'quiz_overview');
}
if ($options->slotmarks) {
foreach ($questions as $slot => $question) {
// Ignore questions of zero length.
$columns[] = 'qsgrade' . $slot;
$header = get_string('qbrief', 'quiz', $question->number);
if (!$table->is_downloading()) {
$header .= '<br />';
} else {
$header .= ' ';
}
$header .= '/' . quiz_rescale_grade($question->maxmark, $quiz, 'question');
$headers[] = $header;
}
}
$this->set_up_table_columns($table, $columns, $headers, $this->get_base_url(), $options, false);
$table->set_attribute('class', 'generaltable generalbox grades');
$table->out($options->pagesize, true);
}
if (!$table->is_downloading() && $options->usercanseegrades) {
$output = $PAGE->get_renderer('mod_quiz');
list($bands, $bandwidth) = self::get_bands_count_and_width($quiz);
$labels = self::get_bands_labels($bands, $bandwidth, $quiz);
if ($currentgroup && $this->hasgroupstudents) {
$sql = "SELECT qg.id
FROM {quiz_grades} qg
JOIN {user} u on u.id = qg.userid
{$groupstudentsjoins->joins}
WHERE qg.quiz = $quiz->id AND {$groupstudentsjoins->wheres}";
if ($DB->record_exists_sql($sql, $groupstudentsjoins->params)) {
$data = quiz_report_grade_bands($bandwidth, $bands, $quiz->id, $groupstudentsjoins);
$chart = self::get_chart($labels, $data);
$graphname = get_string('overviewreportgraphgroup', 'quiz_overview', groups_get_group_name($currentgroup));
echo $output->chart($chart, $graphname);
}
}
if ($DB->record_exists('quiz_grades', array('quiz'=> $quiz->id))) {
$data = quiz_report_grade_bands($bandwidth, $bands, $quiz->id, new \core\dml\sql_join());
$chart = self::get_chart($labels, $data);
$graphname = get_string('overviewreportgraph', 'quiz_overview');
echo $output->chart($chart, $graphname);
}
}
return true;
}
/**
* Extends parent function processing any submitted actions.
*
* @param object $quiz
* @param object $cm
* @param int $currentgroup
* @param \core\dml\sql_join $groupstudentsjoins (joins, wheres, params)
* @param \core\dml\sql_join $allowedjoins (joins, wheres, params)
* @param moodle_url $redirecturl
*/
protected function process_actions($quiz, $cm, $currentgroup, \core\dml\sql_join $groupstudentsjoins,
\core\dml\sql_join $allowedjoins, $redirecturl) {
parent::process_actions($quiz, $cm, $currentgroup, $groupstudentsjoins, $allowedjoins, $redirecturl);
if (empty($currentgroup) || $this->hasgroupstudents) {
if (optional_param('regrade', 0, PARAM_BOOL) && confirm_sesskey()) {
if ($attemptids = optional_param_array('attemptid', array(), PARAM_INT)) {
$this->start_regrade($quiz, $cm);
$this->regrade_attempts($quiz, false, $groupstudentsjoins, $attemptids);
$this->finish_regrade($redirecturl);
}
}
}
if (optional_param('regradeall', 0, PARAM_BOOL) && confirm_sesskey()) {
$this->start_regrade($quiz, $cm);
$this->regrade_attempts($quiz, false, $groupstudentsjoins);
$this->finish_regrade($redirecturl);
} else if (optional_param('regradealldry', 0, PARAM_BOOL) && confirm_sesskey()) {
$this->start_regrade($quiz, $cm);
$this->regrade_attempts($quiz, true, $groupstudentsjoins);
$this->finish_regrade($redirecturl);
} else if (optional_param('regradealldrydo', 0, PARAM_BOOL) && confirm_sesskey()) {
$this->start_regrade($quiz, $cm);
$this->regrade_attempts_needing_it($quiz, $groupstudentsjoins);
$this->finish_regrade($redirecturl);
}
}
/**
* Check necessary capabilities, and start the display of the regrade progress page.
* @param object $quiz the quiz settings.
* @param object $cm the cm object for the quiz.
*/
protected function start_regrade($quiz, $cm) {
require_capability('mod/quiz:regrade', $this->context);
$this->print_header_and_tabs($cm, $this->course, $quiz, $this->mode);
}
/**
* Finish displaying the regrade progress page.
* @param moodle_url $nexturl where to send the user after the regrade.
* @uses exit. This method never returns.
*/
protected function finish_regrade($nexturl) {
global $OUTPUT;
\core\notification::success(get_string('regradecomplete', 'quiz_overview'));
echo $OUTPUT->continue_button($nexturl);
echo $OUTPUT->footer();
die();
}
/**
* Unlock the session and allow the regrading process to run in the background.
*/
protected function unlock_session() {
\core\session\manager::write_close();
ignore_user_abort(true);
}
/**
* Regrade a particular quiz attempt. Either for real ($dryrun = false), or
* as a pretend regrade to see which fractions would change. The outcome is
* stored in the quiz_overview_regrades table.
*
* Note, $attempt is not upgraded in the database. The caller needs to do that.
* However, $attempt->sumgrades is updated, if this is not a dry run.
*
* @param object $attempt the quiz attempt to regrade.
* @param bool $dryrun if true, do a pretend regrade, otherwise do it for real.
* @param array $slots if null, regrade all questions, otherwise, just regrade
* the quetsions with those slots.
*/
protected function regrade_attempt($attempt, $dryrun = false, $slots = null) {
global $DB;
// Need more time for a quiz with many questions.
core_php_time_limit::raise(300);
$transaction = $DB->start_delegated_transaction();
$quba = question_engine::load_questions_usage_by_activity($attempt->uniqueid);
if (is_null($slots)) {
$slots = $quba->get_slots();
}
$finished = $attempt->state == quiz_attempt::FINISHED;
foreach ($slots as $slot) {
$qqr = new stdClass();
$qqr->oldfraction = $quba->get_question_fraction($slot);
$quba->regrade_question($slot, $finished);
$qqr->newfraction = $quba->get_question_fraction($slot);
if (abs($qqr->oldfraction - $qqr->newfraction) > 1e-7) {
$qqr->questionusageid = $quba->get_id();
$qqr->slot = $slot;
$qqr->regraded = empty($dryrun);
$qqr->timemodified = time();
$DB->insert_record('quiz_overview_regrades', $qqr, false);
}
}
if (!$dryrun) {
question_engine::save_questions_usage_by_activity($quba);
}
$transaction->allow_commit();
// Really, PHP should not need this hint, but without this, we just run out of memory.
$quba = null;
$transaction = null;
gc_collect_cycles();
}
/**
* Regrade attempts for this quiz, exactly which attempts are regraded is
* controlled by the parameters.
* @param object $quiz the quiz settings.
* @param bool $dryrun if true, do a pretend regrade, otherwise do it for real.
* @param \core\dml\sql_join|array $groupstudentsjoins empty for all attempts, otherwise regrade attempts
* for these users.
* @param array $attemptids blank for all attempts, otherwise only regrade
* attempts whose id is in this list.
*/
protected function regrade_attempts($quiz, $dryrun = false,
\core\dml\sql_join$groupstudentsjoins = null, $attemptids = array()) {
global $DB;
$this->unlock_session();
$sql = "SELECT quiza.*
FROM {quiz_attempts} quiza";
$where = "quiz = :qid AND preview = 0";
$params = array('qid' => $quiz->id);
if ($this->hasgroupstudents && !empty($groupstudentsjoins->joins)) {
$sql .= "\nJOIN {user} u ON u.id = quiza.userid
{$groupstudentsjoins->joins}";
$where .= " AND {$groupstudentsjoins->wheres}";
$params += $groupstudentsjoins->params;
}
if ($attemptids) {
$aids = join(',', $attemptids);
$where .= " AND quiza.id IN ({$aids})";
}
$sql .= "\nWHERE {$where}";
$attempts = $DB->get_records_sql($sql, $params);
if (!$attempts) {
return;
}
$this->clear_regrade_table($quiz, $groupstudentsjoins);
$progressbar = new progress_bar('quiz_overview_regrade', 500, true);
$a = array(
'count' => count($attempts),
'done' => 0,
);
foreach ($attempts as $attempt) {
$this->regrade_attempt($attempt, $dryrun);
$a['done']++;
$progressbar->update($a['done'], $a['count'],
get_string('regradingattemptxofy', 'quiz_overview', $a));
}
if (!$dryrun) {
$this->update_overall_grades($quiz);
}
}
/**
* Regrade those questions in those attempts that are marked as needing regrading
* in the quiz_overview_regrades table.
* @param object $quiz the quiz settings.
* @param \core\dml\sql_join $groupstudentsjoins empty for all attempts, otherwise regrade attempts
* for these users.
*/
protected function regrade_attempts_needing_it($quiz, \core\dml\sql_join $groupstudentsjoins) {
global $DB;
$this->unlock_session();
$join = '{quiz_overview_regrades} qqr ON qqr.questionusageid = quiza.uniqueid';
$where = "quiza.quiz = :qid AND quiza.preview = 0 AND qqr.regraded = 0";
$params = array('qid' => $quiz->id);
// Fetch all attempts that need regrading.
if ($this->hasgroupstudents && !empty($groupstudentsjoins->joins)) {
$join .= "\nJOIN {user} u ON u.id = quiza.userid
{$groupstudentsjoins->joins}";
$where .= " AND {$groupstudentsjoins->wheres}";
$params += $groupstudentsjoins->params;
}
$toregrade = $DB->get_recordset_sql("
SELECT quiza.uniqueid, qqr.slot
FROM {quiz_attempts} quiza
JOIN $join
WHERE $where", $params);
$attemptquestions = array();
foreach ($toregrade as $row) {
$attemptquestions[$row->uniqueid][] = $row->slot;
}
$toregrade->close();
if (!$attemptquestions) {
return;
}
$attempts = $DB->get_records_list('quiz_attempts', 'uniqueid',
array_keys($attemptquestions));
$this->clear_regrade_table($quiz, $groupstudentsjoins);
$progressbar = new progress_bar('quiz_overview_regrade', 500, true);
$a = array(
'count' => count($attempts),
'done' => 0,
);
foreach ($attempts as $attempt) {
$this->regrade_attempt($attempt, false, $attemptquestions[$attempt->uniqueid]);
$a['done']++;
$progressbar->update($a['done'], $a['count'],
get_string('regradingattemptxofy', 'quiz_overview', $a));
}
$this->update_overall_grades($quiz);
}
/**
* Count the number of attempts in need of a regrade.
* @param object $quiz the quiz settings.
* @param \core\dml\sql_join $groupstudentsjoins (joins, wheres, params) If this is given, only data relating
* to these users is cleared.
*/
protected function count_question_attempts_needing_regrade($quiz, \core\dml\sql_join $groupstudentsjoins) {
global $DB;
$userjoin = '';
$usertest = '';
$params = array();
if ($this->hasgroupstudents) {
$userjoin = "JOIN {user} u ON u.id = quiza.userid
{$groupstudentsjoins->joins}";
$usertest = "{$groupstudentsjoins->wheres} AND u.id = quiza.userid AND ";
$params = $groupstudentsjoins->params;
}
$params['cquiz'] = $quiz->id;
$sql = "SELECT COUNT(DISTINCT quiza.id)
FROM {quiz_attempts} quiza
JOIN {quiz_overview_regrades} qqr ON quiza.uniqueid = qqr.questionusageid
$userjoin
WHERE
$usertest
quiza.quiz = :cquiz AND
quiza.preview = 0 AND
qqr.regraded = 0";
return $DB->count_records_sql($sql, $params);
}
/**
* Are there any pending regrades in the table we are going to show?
* @param string $from tables used by the main query.
* @param string $where where clause used by the main query.
* @param array $params required by the SQL.
* @return bool whether there are pending regrades.
*/
protected function has_regraded_questions($from, $where, $params) {
global $DB;
return $DB->record_exists_sql("
SELECT 1
FROM {$from}
JOIN {quiz_overview_regrades} qor ON qor.questionusageid = quiza.uniqueid
WHERE {$where}", $params);
}
/**
* Remove all information about pending/complete regrades from the database.
* @param object $quiz the quiz settings.
* @param \core\dml\sql_join $groupstudentsjoins (joins, wheres, params). If this is given, only data relating
* to these users is cleared.
*/
protected function clear_regrade_table($quiz, \core\dml\sql_join $groupstudentsjoins) {
global $DB;
// Fetch all attempts that need regrading.
$select = "questionusageid IN (
SELECT uniqueid
FROM {quiz_attempts} quiza";
$where = "WHERE quiza.quiz = :qid";
$params = array('qid' => $quiz->id);
if ($this->hasgroupstudents && !empty($groupstudentsjoins->joins)) {
$select .= "\nJOIN {user} u ON u.id = quiza.userid
{$groupstudentsjoins->joins}";
$where .= " AND {$groupstudentsjoins->wheres}";
$params += $groupstudentsjoins->params;
}
$select .= "\n$where)";
$DB->delete_records_select('quiz_overview_regrades', $select, $params);
}
/**
* Update the final grades for all attempts. This method is used following
* a regrade.
* @param object $quiz the quiz settings.
* @param array $userids only update scores for these userids.
* @param array $attemptids attemptids only update scores for these attempt ids.
*/
protected function update_overall_grades($quiz) {
quiz_update_all_attempt_sumgrades($quiz);
quiz_update_all_final_grades($quiz);
quiz_update_grades($quiz);
}
/**
* Get the bands configuration for the quiz.
*
* This returns the configuration for having between 11 and 20 bars in
* a chart based on the maximum grade to be given on a quiz. The width of
* a band is the number of grade points it encapsulates.
*
* @param object $quiz The quiz object.
* @return array Contains the number of bands, and their width.
*/
public static function get_bands_count_and_width($quiz) {
$bands = $quiz->grade;
while ($bands > 20 || $bands <= 10) {
if ($bands > 50) {
$bands /= 5;
} else if ($bands > 20) {
$bands /= 2;
}
if ($bands < 4) {
$bands *= 5;
} else if ($bands <= 10) {
$bands *= 2;
}
}
// See MDL-34589. Using doubles as array keys causes problems in PHP 5.4, hence the explicit cast to int.
$bands = (int) ceil($bands);
return [$bands, $quiz->grade / $bands];
}
/**
* Get the bands labels.
*
* @param int $bands The number of bands.
* @param int $bandwidth The band width.
* @param object $quiz The quiz object.
* @return string[] The labels.
*/
public static function get_bands_labels($bands, $bandwidth, $quiz) {
$bandlabels = [];
for ($i = 1; $i <= $bands; $i++) {
$bandlabels[] = quiz_format_grade($quiz, ($i - 1) * $bandwidth) . ' - ' . quiz_format_grade($quiz, $i * $bandwidth);
}
return $bandlabels;
}
/**
* Get a chart.
*
* @param string[] $labels Chart labels.
* @param int[] $data The data.
* @return \core\chart_base
*/
protected static function get_chart($labels, $data) {
$chart = new \core\chart_bar();
$chart->set_labels($labels);
$chart->get_xaxis(0, true)->set_label(get_string('grade'));
$yaxis = $chart->get_yaxis(0, true);
$yaxis->set_label(get_string('participants'));
$yaxis->set_stepsize(max(1, round(max($data) / 10)));
$series = new \core\chart_series(get_string('participants'), $data);
$chart->add_series($series);
return $chart;
}
}