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807 lines
32 KiB
PHP
807 lines
32 KiB
PHP
<?php
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/**
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* This class keeps track of the various access rules that apply to a particular
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* quiz, with convinient methods for seeing whether access is allowed.
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*/
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class quiz_access_manager {
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private $_quizobj;
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private $_timenow;
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private $_passwordrule = null;
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private $_securewindowrule = null;
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private $_safebrowserrule = null;
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private $_rules = array();
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/**
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* Create an instance for a particular quiz.
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* @param object $quizobj An instance of the class quiz from attemptlib.php.
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* The quiz we will be controlling access to.
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* @param integer $timenow The time to use as 'now'.
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* @param boolean $canignoretimelimits Whether this user is exempt from time
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* limits (has_capability('mod/quiz:ignoretimelimits', ...)).
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*/
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public function __construct($quizobj, $timenow, $canignoretimelimits) {
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$this->_quizobj = $quizobj;
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$this->_timenow = $timenow;
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$this->create_standard_rules($canignoretimelimits);
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}
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private function create_standard_rules($canignoretimelimits) {
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$quiz = $this->_quizobj->get_quiz();
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if ($quiz->attempts > 0) {
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$this->_rules[] = new num_attempts_access_rule($this->_quizobj, $this->_timenow);
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}
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$this->_rules[] = new open_close_date_access_rule($this->_quizobj, $this->_timenow);
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if (!empty($quiz->timelimit) && !$canignoretimelimits) {
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$this->_rules[] = new time_limit_access_rule($this->_quizobj, $this->_timenow);
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}
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if (!empty($quiz->delay1) || !empty($quiz->delay2)) {
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$this->_rules[] = new inter_attempt_delay_access_rule($this->_quizobj, $this->_timenow);
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}
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if (!empty($quiz->subnet)) {
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$this->_rules[] = new ipaddress_access_rule($this->_quizobj, $this->_timenow);
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}
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if (!empty($quiz->password)) {
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$this->_passwordrule = new password_access_rule($this->_quizobj, $this->_timenow);
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$this->_rules[] = $this->_passwordrule;
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}
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if (!empty($quiz->popup)) {
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if ($quiz->popup == 1) {
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$this->_securewindowrule = new securewindow_access_rule($this->_quizobj, $this->_timenow);
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$this->_rules[] = $this->_securewindowrule;
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} elseif ($quiz->popup == 2) {
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$this->_safebrowserrule = new safebrowser_access_rule($this->_quizobj, $this->_timenow);
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$this->_rules[] = $this->_safebrowserrule;
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}
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}
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}
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private function accumulate_messages(&$messages, $new) {
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if (is_array($new)) {
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$messages = array_merge($messages, $new);
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} else if (is_string($new) && $new) {
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$messages[] = $new;
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}
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}
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/**
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* Print each message in an array, surrounded by <p>, </p> tags.
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*
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* @param array $messages the array of message strings.
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* @param boolean $return if true, return a string, instead of outputting.
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*
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* @return mixed, if $return is true, return the string that would have been output, otherwise
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* return null.
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*/
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public function print_messages($messages, $return=false) {
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$output = '';
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foreach ($messages as $message) {
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$output .= '<p>' . $message . "</p>\n";
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}
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if ($return) {
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return $output;
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} else {
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echo $output;
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}
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}
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/**
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* Provide a description of the rules that apply to this quiz, such
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* as is shown at the top of the quiz view page. Note that not all
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* rules consider themselves important enough to output a description.
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*
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* @return array an array of description messages which may be empty. It
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* would be sensible to output each one surrounded by <p> tags.
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*/
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public function describe_rules() {
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$result = array();
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foreach ($this->_rules as $rule) {
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$this->accumulate_messages($result, $rule->description());
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}
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return $result;
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}
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/**
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* Is it OK to let the current user start a new attempt now? If there are
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* any restrictions in force now, return an array of reasons why access
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* should be blocked. If access is OK, return false.
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*
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* @param integer $numattempts the number of previous attempts this user has made.
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* @param object|false $lastattempt information about the user's last completed attempt.
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* if there is not a previous attempt, the false is passed.
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* @return mixed An array of reason why access is not allowed, or an empty array
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* (== false) if access should be allowed.
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*/
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public function prevent_new_attempt($numprevattempts, $lastattempt) {
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$reasons = array();
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foreach ($this->_rules as $rule) {
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$this->accumulate_messages($reasons,
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$rule->prevent_new_attempt($numprevattempts, $lastattempt));
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}
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return $reasons;
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}
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/**
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* Is it OK to let the current user start a new attempt now? If there are
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* any restrictions in force now, return an array of reasons why access
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* should be blocked. If access is OK, return false.
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*
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* @return mixed An array of reason why access is not allowed, or an empty array
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* (== false) if access should be allowed.
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*/
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public function prevent_access() {
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$reasons = array();
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foreach ($this->_rules as $rule) {
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$this->accumulate_messages($reasons, $rule->prevent_access());
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}
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return $reasons;
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}
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/**
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* Do any of the rules mean that this student will no be allowed any further attempts at this
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* quiz. Used, for example, to change the label by the grade displayed on the view page from
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* 'your current score is' to 'your final score is'.
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*
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* @param integer $numattempts the number of previous attempts this user has made.
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* @param object $lastattempt information about the user's last completed attempt.
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* @return boolean true if there is no way the user will ever be allowed to attempt this quiz again.
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*/
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public function is_finished($numprevattempts, $lastattempt) {
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foreach ($this->_rules as $rule) {
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if ($rule->is_finished($numprevattempts, $lastattempt)) {
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return true;
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}
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}
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return false;
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}
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/**
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* Do the printheader call, etc. required for a secure page, including the necessary JS.
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*
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* @param string $title HTML title tag content, passed to printheader.
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* @param string $headtags extra stuff to go in the HTML head tag, passed to printheader.
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*/
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public function setup_secure_page($title, $headtags = null) {
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$this->_securewindowrule->setup_secure_page($title, $headtags);
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}
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public function show_attempt_timer_if_needed($attempt, $timenow) {
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global $PAGE;
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$timeleft = false;
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foreach ($this->_rules as $rule) {
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$ruletimeleft = $rule->time_left($attempt, $timenow);
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if ($ruletimeleft !== false && ($timeleft === false || $ruletimeleft < $timeleft)) {
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$timeleft = $ruletimeleft;
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}
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}
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if ($timeleft !== false) {
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/// Make sure the timer starts just above zero. If $timeleft was <= 0, then
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/// this will just have the effect of causing the quiz to be submitted immediately.
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$timerstartvalue = max($timeleft, 1);
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$PAGE->requires->js_init_call('M.mod_quiz.timer.init',
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array($timerstartvalue), false, quiz_get_js_module());
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}
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}
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/**
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* @return bolean if this quiz should only be shown to students in a secure window.
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*/
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public function securewindow_required($canpreview) {
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return !$canpreview && !is_null($this->_securewindowrule);
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}
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/**
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* @return bolean if this quiz should only be shown to students with safe browser.
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*/
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public function safebrowser_required($canpreview) {
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return !$canpreview && !is_null($this->_safebrowserrule);
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}
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/**
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* Print a button to start a quiz attempt, with an appropriate javascript warning,
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* depending on the access restrictions. The link will pop up a 'secure' window, if
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* necessary.
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*
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* @param boolean $canpreview whether this user can preview. This affects whether they must
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* use a secure window.
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* @param string $buttontext the label to put on the button.
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* @param boolean $unfinished whether the button is to continue an existing attempt,
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* or start a new one. This affects whether a javascript alert is shown.
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*/
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public function print_start_attempt_button($canpreview, $buttontext, $unfinished) {
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global $OUTPUT;
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$url = $this->_quizobj->start_attempt_url();
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$button = new single_button($url, $buttontext);
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$button->class .= ' quizstartbuttondiv';
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if (!$unfinished) {
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$strconfirmstartattempt = $this->confirm_start_attempt_message();
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if ($strconfirmstartattempt) {
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$button->add_confirm_action($strconfirmstartattempt);
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}
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}
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$warning = '';
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if ($this->securewindow_required($canpreview)) {
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$button->class .= ' quizsecuremoderequired';
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$button->add_action(new popup_action('click', $url, 'quizpopup',
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securewindow_access_rule::$popupoptions));
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$warning = html_writer::tag('noscript',
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$OUTPUT->heading(get_string('noscript', 'quiz')));
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}
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echo $OUTPUT->render($button) . $warning;
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}
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/**
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* Send the user back to the quiz view page. Normally this is just a redirect, but
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* If we were in a secure window, we close this window, and reload the view window we came from.
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*
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* @param boolean $canpreview This affects whether we have to worry about secure window stuff.
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*/
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public function back_to_view_page($canpreview, $message = '') {
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global $CFG, $OUTPUT, $PAGE;
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$url = $this->_quizobj->view_url();
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if ($this->securewindow_required($canpreview)) {
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$PAGE->set_pagelayout('popup');
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echo $OUTPUT->header();
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echo $OUTPUT->box_start();
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if ($message) {
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echo '<p>' . $message . '</p><p>' . get_string('windowclosing', 'quiz') . '</p>';
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$delay = 5;
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} else {
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echo '<p>' . get_string('pleaseclose', 'quiz') . '</p>';
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$delay = 0;
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}
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$PAGE->requires->js_function_call('M.mod_quiz.secure_window.close', array($url, $delay));
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echo $OUTPUT->box_end();
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echo $OUTPUT->footer();
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die();
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} else {
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redirect($url, $message);
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}
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}
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/**
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* Print a control to finish the review. Normally this is just a link, but if we are
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* in a secure window, it needs to be a button that does M.mod_quiz.secure_window.close.
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*
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* @param boolean $canpreview This affects whether we have to worry about secure window stuff.
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*/
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public function print_finish_review_link($canpreview, $return = false) {
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global $CFG;
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$output = '';
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$url = $this->_quizobj->view_url();
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$output .= '<div class="finishreview">';
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if ($this->securewindow_required($canpreview)) {
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$url = addslashes_js(htmlspecialchars($url));
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$output .= '<input type="button" value="' . get_string('finishreview', 'quiz') . '" ' .
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"onclick=\"M.mod_quiz.secure_window.close('$url', 0)\" />\n";
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} else {
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$output .= '<a href="' . $url . '">' . get_string('finishreview', 'quiz') . "</a>\n";
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}
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$output .= "</div>\n";
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if ($return) {
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return $output;
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} else {
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echo $output;
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}
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}
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/**
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* @return bolean if this quiz is password protected.
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*/
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public function password_required() {
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return !is_null($this->_passwordrule);
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}
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/**
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* Clear the flag in the session that says that the current user is allowed to do this quiz.
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*/
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public function clear_password_access() {
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if (!is_null($this->_passwordrule)) {
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$this->_passwordrule->clear_access_allowed();
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}
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}
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/**
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* Actually ask the user for the password, if they have not already given it this session.
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* This function only returns is access is OK.
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*
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* @param boolean $canpreview used to enfore securewindow stuff.
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*/
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public function do_password_check($canpreview) {
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if (!is_null($this->_passwordrule)) {
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$this->_passwordrule->do_password_check($canpreview, $this);
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}
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}
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/**
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* @return string if the quiz policies merit it, return a warning string to be displayed
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* in a javascript alert on the start attempt button.
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*/
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public function confirm_start_attempt_message() {
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$quiz = $this->_quizobj->get_quiz();
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if ($quiz->timelimit && $quiz->attempts) {
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return get_string('confirmstartattempttimelimit','quiz', $quiz->attempts);
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} else if ($quiz->timelimit) {
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return get_string('confirmstarttimelimit','quiz');
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} else if ($quiz->attempts) {
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return get_string('confirmstartattemptlimit','quiz', $quiz->attempts);
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}
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return '';
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}
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/**
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* Make some text into a link to review the quiz, if that is appropriate.
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*
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* @param string $linktext some text.
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* @param object $attempt the attempt object
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* @return string some HTML, the $linktext either unmodified or wrapped in a link to the review page.
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*/
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public function make_review_link($attempt, $canpreview, $reviewoptions) {
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global $CFG;
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/// If review of responses is not allowed, or the attempt is still open, don't link.
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if (!$attempt->timefinish) {
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return '';
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}
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if (!$reviewoptions->responses) {
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$message = $this->cannot_review_message($reviewoptions, true);
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if ($message) {
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return '<span class="noreviewmessage">' . $message . '</span>';
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} else {
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return '';
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}
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}
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$linktext = get_string('review', 'quiz');
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/// It is OK to link, does it need to be in a secure window?
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if ($this->securewindow_required($canpreview)) {
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return $this->_securewindowrule->make_review_link($linktext, $attempt->id);
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} else {
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return '<a href="' . $this->_quizobj->review_url($attempt->id) . '" title="' .
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get_string('reviewthisattempt', 'quiz') . '">' . $linktext . '</a>';
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}
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}
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/**
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* If $reviewoptions->responses is false, meaning that students can't review this
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* attempt at the moment, return an appropriate string explaining why.
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*
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* @param object $reviewoptions as obtained from quiz_get_reviewoptions.
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* @param boolean $short if true, return a shorter string.
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* @return string an appropraite message.
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*/
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public function cannot_review_message($reviewoptions, $short = false) {
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$quiz = $this->_quizobj->get_quiz();
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if ($short) {
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$langstrsuffix = 'short';
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$dateformat = get_string('strftimedatetimeshort', 'langconfig');
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} else {
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$langstrsuffix = '';
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$dateformat = '';
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}
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if ($reviewoptions->quizstate == QUIZ_STATE_IMMEDIATELY) {
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return '';
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} else if ($reviewoptions->quizstate == QUIZ_STATE_OPEN && $quiz->timeclose &&
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($quiz->review & QUIZ_REVIEW_CLOSED & QUIZ_REVIEW_RESPONSES)) {
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return get_string('noreviewuntil' . $langstrsuffix, 'quiz', userdate($quiz->timeclose, $dateformat));
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} else {
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return get_string('noreview' . $langstrsuffix, 'quiz');
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}
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}
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}
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/**
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* A base class that defines the interface for the various quiz access rules.
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* Most of the methods are defined in a slightly unnatural way because we either
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* want to say that access is allowed, or explain the reason why it is block.
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* Therefore instead of is_access_allowed(...) we have prevent_access(...) that
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* return false if access is permitted, or a string explanation (which is treated
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* as true) if access should be blocked. Slighly unnatural, but acutally the easist
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* way to implement this.
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*/
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abstract class quiz_access_rule_base {
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protected $_quiz;
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protected $_quizobj;
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protected $_timenow;
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/**
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* Create an instance of this rule for a particular quiz.
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* @param object $quiz the quiz we will be controlling access to.
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*/
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public function __construct($quizobj, $timenow) {
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$this->_quizobj = $quizobj;
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$this->_quiz = $quizobj->get_quiz();
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$this->_timenow = $timenow;
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}
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/**
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* Whether or not a user should be allowed to start a new attempt at this quiz now.
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* @param integer $numattempts the number of previous attempts this user has made.
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* @param object $lastattempt information about the user's last completed attempt.
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* @return string false if access should be allowed, a message explaining the reason if access should be prevented.
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*/
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public function prevent_new_attempt($numprevattempts, $lastattempt) {
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return false;
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}
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/**
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* Whether or not a user should be allowed to start a new attempt at this quiz now.
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* @return string false if access should be allowed, a message explaining the reason if access should be prevented.
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*/
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public function prevent_access() {
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return false;
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}
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/**
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* Information, such as might be shown on the quiz view page, relating to this restriction.
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* There is no obligation to return anything. If it is not appropriate to tell students
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* about this rule, then just return ''.
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* @return mixed a message, or array of messages, explaining the restriction
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* (may be '' if no message is appropriate).
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*/
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public function description() {
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return '';
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}
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/**
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* If this rule can determine that this user will never be allowed another attempt at
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* this quiz, then return true. This is used so we can know whether to display a
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* final score on the view page. This will only be called if there is not a currently
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* active attempt for this user.
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* @param integer $numattempts the number of previous attempts this user has made.
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* @param object $lastattempt information about the user's last completed attempt.
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* @return boolean true if this rule means that this user will never be allowed another
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* attempt at this quiz.
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*/
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public function is_finished($numprevattempts, $lastattempt) {
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return false;
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}
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/**
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* If, becuase of this rule, the user has to finish their attempt by a certain time,
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* you should override this method to return the amount of time left in seconds.
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* @param object $attempt the current attempt
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* @param integer $timenow the time now. We don't use $this->_timenow, so we can
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* give the user a more accurate indication of how much time is left.
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* @return mixed false if there is no deadline, of the time left in seconds if there is one.
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*/
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public function time_left($attempt, $timenow) {
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return false;
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}
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}
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/**
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* A rule controlling the number of attempts allowed.
|
|
*/
|
|
class num_attempts_access_rule extends quiz_access_rule_base {
|
|
public function description() {
|
|
return get_string('attemptsallowedn', 'quiz', $this->_quiz->attempts);
|
|
}
|
|
public function prevent_new_attempt($numprevattempts, $lastattempt) {
|
|
if ($numprevattempts >= $this->_quiz->attempts) {
|
|
return get_string('nomoreattempts', 'quiz');
|
|
}
|
|
return false;
|
|
}
|
|
public function is_finished($numprevattempts, $lastattempt) {
|
|
return $numprevattempts >= $this->_quiz->attempts;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* A rule enforcing open and close dates.
|
|
*/
|
|
class open_close_date_access_rule extends quiz_access_rule_base {
|
|
public function description() {
|
|
$result = array();
|
|
if ($this->_timenow < $this->_quiz->timeopen) {
|
|
$result[] = get_string('quiznotavailable', 'quiz', userdate($this->_quiz->timeopen));
|
|
} else if ($this->_quiz->timeclose && $this->_timenow > $this->_quiz->timeclose) {
|
|
$result[] = get_string("quizclosed", "quiz", userdate($this->_quiz->timeclose));
|
|
} else {
|
|
if ($this->_quiz->timeopen) {
|
|
$result[] = get_string('quizopenedon', 'quiz', userdate($this->_quiz->timeopen));
|
|
}
|
|
if ($this->_quiz->timeclose) {
|
|
$result[] = get_string('quizcloseson', 'quiz', userdate($this->_quiz->timeclose));
|
|
}
|
|
}
|
|
return $result;
|
|
}
|
|
public function prevent_access() {
|
|
if ($this->_timenow < $this->_quiz->timeopen ||
|
|
($this->_quiz->timeclose && $this->_timenow > $this->_quiz->timeclose)) {
|
|
return get_string('notavailable', 'quiz');
|
|
}
|
|
return false;
|
|
}
|
|
public function is_finished($numprevattempts, $lastattempt) {
|
|
return $this->_quiz->timeclose && $this->_timenow > $this->_quiz->timeclose;
|
|
}
|
|
public function time_left($attempt, $timenow) {
|
|
// If this is a teacher preview after the close date, do not show
|
|
// the time.
|
|
if ($attempt->preview && $timenow > $this->_quiz->timeclose) {
|
|
return false;
|
|
}
|
|
|
|
// Otherwise, return to the time left until the close date, providing
|
|
// that is less than QUIZ_SHOW_TIME_BEFORE_DEADLINE
|
|
if ($this->_quiz->timeclose) {
|
|
$timeleft = $this->_quiz->timeclose - $timenow;
|
|
if ($timeleft < QUIZ_SHOW_TIME_BEFORE_DEADLINE) {
|
|
return $timeleft;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* A rule imposing the delay between attemtps settings.
|
|
*/
|
|
class inter_attempt_delay_access_rule extends quiz_access_rule_base {
|
|
public function prevent_new_attempt($numprevattempts, $lastattempt) {
|
|
if ($this->_quiz->attempts > 0 && $numprevattempts >= $this->_quiz->attempts) {
|
|
/// No more attempts allowed anyway.
|
|
return false;
|
|
}
|
|
if ($this->_quiz->timeclose != 0 && $this->_timenow > $this->_quiz->timeclose) {
|
|
/// No more attempts allowed anyway.
|
|
return false;
|
|
}
|
|
$nextstarttime = $this->compute_next_start_time($numprevattempts, $lastattempt);
|
|
if ($this->_timenow < $nextstarttime) {
|
|
if ($this->_quiz->timeclose == 0 || $nextstarttime <= $this->_quiz->timeclose) {
|
|
return get_string('youmustwait', 'quiz', userdate($nextstarttime));
|
|
} else {
|
|
return get_string('youcannotwait', 'quiz');
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Compute the next time a student would be allowed to start an attempt,
|
|
* according to this rule.
|
|
* @param integer $numprevattempts number of previous attempts.
|
|
* @param object $lastattempt information about the previous attempt.
|
|
* @return number the time.
|
|
*/
|
|
protected function compute_next_start_time($numprevattempts, $lastattempt) {
|
|
if ($numprevattempts == 0) {
|
|
return 0;
|
|
}
|
|
|
|
$lastattemptfinish = $lastattempt->timefinish;
|
|
if ($this->_quiz->timelimit > 0){
|
|
$lastattemptfinish = min($lastattemptfinish,
|
|
$lastattempt->timestart + $this->_quiz->timelimit);
|
|
}
|
|
|
|
if ($numprevattempts == 1 && $this->_quiz->delay1) {
|
|
return $lastattemptfinish + $this->_quiz->delay1;
|
|
} else if ($numprevattempts > 1 && $this->_quiz->delay2) {
|
|
return $lastattemptfinish + $this->_quiz->delay2;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
public function is_finished($numprevattempts, $lastattempt) {
|
|
$nextstarttime = $this->compute_next_start_time($numprevattempts, $lastattempt);
|
|
return $this->_timenow <= $nextstarttime &&
|
|
$this->_quiz->timeclose != 0 && $nextstarttime >= $this->_quiz->timeclose;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* A rule implementing the ipaddress check against the ->submet setting.
|
|
*/
|
|
class ipaddress_access_rule extends quiz_access_rule_base {
|
|
public function prevent_access() {
|
|
if (address_in_subnet(getremoteaddr(), $this->_quiz->subnet)) {
|
|
return false;
|
|
} else {
|
|
return get_string('subnetwrong', 'quiz');
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* A rule representing the password check. It does not actually implement the check,
|
|
* that has to be done directly in attempt.php, but this facilitates telling users about it.
|
|
*/
|
|
class password_access_rule extends quiz_access_rule_base {
|
|
public function description() {
|
|
return get_string('requirepasswordmessage', 'quiz');
|
|
}
|
|
/**
|
|
* Clear the flag in the session that says that the current user is allowed to do this quiz.
|
|
*/
|
|
public function clear_access_allowed() {
|
|
global $SESSION;
|
|
if (!empty($SESSION->passwordcheckedquizzes[$this->_quiz->id])) {
|
|
unset($SESSION->passwordcheckedquizzes[$this->_quiz->id]);
|
|
}
|
|
}
|
|
/**
|
|
* Actually ask the user for the password, if they have not already given it this session.
|
|
* This function only returns is access is OK.
|
|
*
|
|
* @param boolean $canpreview used to enfore securewindow stuff.
|
|
* @param object $accessmanager the accessmanager calling us.
|
|
*/
|
|
public function do_password_check($canpreview, $accessmanager) {
|
|
global $CFG, $SESSION, $OUTPUT, $PAGE;
|
|
|
|
/// We have already checked the password for this quiz this session, so don't ask again.
|
|
if (!empty($SESSION->passwordcheckedquizzes[$this->_quiz->id])) {
|
|
return;
|
|
}
|
|
|
|
/// If the user cancelled the password form, send them back to the view page.
|
|
if (optional_param('cancelpassword', false, PARAM_BOOL)) {
|
|
$accessmanager->back_to_view_page($canpreview);
|
|
}
|
|
|
|
/// If they entered the right password, let them in.
|
|
$enteredpassword = optional_param('quizpassword', '', PARAM_RAW);
|
|
$validpassword = false;
|
|
if (strcmp($this->_quiz->password, $enteredpassword) === 0) {
|
|
$validpassword = true;
|
|
} else if (isset($this->_quiz->extrapasswords)) {
|
|
// group overrides may have additional passwords
|
|
foreach ($this->_quiz->extrapasswords as $password) {
|
|
if (strcmp($password, $enteredpassword) === 0) {
|
|
$validpassword = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if ($validpassword) {
|
|
$SESSION->passwordcheckedquizzes[$this->_quiz->id] = true;
|
|
return;
|
|
}
|
|
|
|
/// User entered the wrong password, or has not entered one yet, so display the form.
|
|
$output = '';
|
|
|
|
/// Start the page and print the quiz intro, if any.
|
|
if ($accessmanager->securewindow_required($canpreview)) {
|
|
$accessmanager->setup_secure_page($this->_quizobj->get_course()->shortname . ': ' .
|
|
format_string($this->_quizobj->get_quiz_name()));
|
|
} else if ($accessmanager->safebrowser_required($canpreview)) {
|
|
$PAGE->set_title($this->_quizobj->get_course()->shortname . ': '.format_string($this->_quizobj->get_quiz_name()));
|
|
$PAGE->set_cacheable(false);
|
|
echo $OUTPUT->header();
|
|
} else {
|
|
$PAGE->set_title(format_string($this->_quizobj->get_quiz_name()));
|
|
echo $OUTPUT->header();
|
|
}
|
|
|
|
if (trim(strip_tags($this->_quiz->intro))) {
|
|
$output .= $OUTPUT->box(format_module_intro('quiz', $this->_quiz, $this->_quizobj->get_cmid()), 'generalbox', 'intro');
|
|
}
|
|
$output .= $OUTPUT->box_start('generalbox', 'passwordbox');
|
|
|
|
/// If they have previously tried and failed to enter a password, tell them it was wrong.
|
|
if (!empty($enteredpassword)) {
|
|
$output .= '<p class="notifyproblem">' . get_string('passworderror', 'quiz') . '</p>';
|
|
}
|
|
|
|
/// Print the password entry form.
|
|
$output .= '<p>' . get_string('requirepasswordmessage', 'quiz') . "</p>\n";
|
|
$output .= '<form id="passwordform" method="post" action="' . $CFG->wwwroot .
|
|
'/mod/quiz/startattempt.php" onclick="this.autocomplete=\'off\'">' . "\n";
|
|
$output .= "<div>\n";
|
|
$output .= '<label for="quizpassword">' . get_string('password') . "</label>\n";
|
|
$output .= '<input name="quizpassword" id="quizpassword" type="password" value=""/>' . "\n";
|
|
$output .= '<input name="cmid" type="hidden" value="' .
|
|
$this->_quizobj->get_cmid() . '"/>' . "\n";
|
|
$output .= '<input name="sesskey" type="hidden" value="' . sesskey() . '"/>' . "\n";
|
|
$output .= '<input type="submit" value="' . get_string('ok') . '" />';
|
|
$output .= '<input type="submit" name="cancelpassword" value="' .
|
|
get_string('cancel') . '" />' . "\n";
|
|
$output .= "</div>\n";
|
|
$output .= "</form>\n";
|
|
|
|
/// Finish page.
|
|
$output .= $OUTPUT->box_end();
|
|
|
|
/// return or display form.
|
|
echo $output;
|
|
echo $OUTPUT->footer();
|
|
exit;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* A rule representing the time limit. It does not actually restrict access, but we use this
|
|
* class to encapsulate some of the relevant code.
|
|
*/
|
|
class time_limit_access_rule extends quiz_access_rule_base {
|
|
public function description() {
|
|
return get_string('quiztimelimit', 'quiz', format_time($this->_quiz->timelimit));
|
|
}
|
|
public function time_left($attempt, $timenow) {
|
|
return $attempt->timestart + $this->_quiz->timelimit - $timenow;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* A rule for ensuring that the quiz is opened in a popup, with some JavaScript
|
|
* to prevent copying and pasting, etc.
|
|
*/
|
|
class securewindow_access_rule extends quiz_access_rule_base {
|
|
/**
|
|
* @var array options that should be used for opening the secure popup.
|
|
*/
|
|
public static $popupoptions = array(
|
|
'left' => 0,
|
|
'top' => 0,
|
|
'fullscreen' => true,
|
|
'scrollbars' => true,
|
|
'resizeable' => false,
|
|
'directories' => false,
|
|
'toolbar' => false,
|
|
'titlebar' => false,
|
|
'location' => false,
|
|
'status' => false,
|
|
'menubar' => false,
|
|
);
|
|
|
|
/**
|
|
* Make a link to the review page for an attempt.
|
|
*
|
|
* @param string $linktext the desired link text.
|
|
* @param integer $attemptid the attempt id.
|
|
* @return string HTML for the link.
|
|
*/
|
|
public function make_review_link($linktext, $attemptid) {
|
|
global $OUTPUT;
|
|
$url = $this->_quizobj->review_url($attemptid);
|
|
$button = new single_button($url, $linktext);
|
|
$button->add_action(new popup_action('click', $url, 'quizpopup', self::$popupoptions));
|
|
return $OUTPUT->render($button);
|
|
}
|
|
|
|
/**
|
|
* Do the printheader call, etc. required for a secure page, including the necessary JS.
|
|
*
|
|
* @param string $title HTML title tag content, passed to printheader.
|
|
* @param string $headtags extra stuff to go in the HTML head tag, passed to printheader.
|
|
* $headtags has been deprectaed since Moodle 2.0
|
|
*/
|
|
public function setup_secure_page($title, $headtags=null) {
|
|
global $OUTPUT, $PAGE;
|
|
$PAGE->set_popup_notification_allowed(false);//prevent message notifications
|
|
$PAGE->set_title($title);
|
|
$PAGE->set_cacheable(false);
|
|
$PAGE->set_pagelayout('popup');
|
|
$PAGE->add_body_class('quiz-secure-window');
|
|
$PAGE->requires->js_init_call('M.mod_quiz.secure_window.init', null, false,
|
|
quiz_get_js_module());
|
|
echo $OUTPUT->header();
|
|
}
|
|
}
|
|
|
|
/**
|
|
* A rule representing the safe browser check.
|
|
*/
|
|
class safebrowser_access_rule extends quiz_access_rule_base {
|
|
public function prevent_access() {
|
|
if (!$this->_quizobj->is_preview_user() && !quiz_check_safe_browser()) {
|
|
return get_string('safebrowsererror', 'quiz');
|
|
} else {
|
|
return false;
|
|
}
|
|
}
|
|
|
|
public function description() {
|
|
return get_string("safebrowsernotice", "quiz");
|
|
}
|
|
}
|
|
|