question/previewlib.php

   1 <?php
   2
   3 // This file is part of Moodle - http://moodle.org/
   4 //
   5 // Moodle is free software: you can redistribute it and/or modify
   6 // it under the terms of the GNU General Public License as published by
   7 // the Free Software Foundation, either version 3 of the License, or
   8 // (at your option) any later version.
   9 //
  10 // Moodle is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14 //
  15 // You should have received a copy of the GNU General Public License
  16 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  17
  18 /**
  19  * Library functions used by question/preview.php.
  20  *
  21  * @package    core
  22  * @subpackage questionengine
  23  * @copyright  2010 The Open University
  24  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  25  */
  26
  27 /**
  28  * Called via pluginfile.php -> question_pluginfile to serve files belonging to
  29  * a question in a question_attempt when that attempt is a preview.
  30  *
  31  * @param object $course course settings object
  32  * @param object $context context object
  33  * @param string $component the name of the component we are serving files for.
  34  * @param string $filearea the name of the file area.
  35  * @param array $args the remaining bits of the file path.
  36  * @param bool $forcedownload whether the user must be forced to download the file.
  37  * @return bool false if file not found, does not return if found - justsend the file
  38  */
  39 function question_preview_question_pluginfile($course, $context, $component,
  40         $filearea, $attemptid, $questionid, $args, $forcedownload) {
  41     global $USER, $SESSION, $DB, $CFG;
  42     require_once($CFG->dirroot . '/mod/quiz/locallib.php');
  43
  44     if (!$question = $DB->get_record('question', array('id' => $questionid))) {
  45         return send_file_not_found();
  46     }
  47
  48     if (!question_has_capability_on($question, 'use', $question->category)) {
  49         send_file_not_found();
  50     }
  51
  52     if (!isset($SESSION->quizpreview->states) || $SESSION->quizpreview->questionid != $questionid) {
  53         send_file_not_found();
  54     }
  55
  56     $states = end($SESSION->quizpreview->states);
  57     if (!array_key_exists($question->id, $states)) {
  58         send_file_not_found();
  59     }
  60     $state = $states[$question->id];
  61
  62     // Build fake cmoptions
  63     $quiz = new cmoptions;
  64     $quiz->id = 0;
  65     $quiz->review = get_config('quiz', 'review');
  66     if (empty($course->id)) {
  67         $quiz->course = SITEID;
  68     } else {
  69         $quiz->course = $course->id;
  70     }
  71     $quiz->decimalpoints = get_config('quiz', 'decimalpoints');
  72
  73     $questions[$question->id] = $question;
  74     get_question_options($questions);
  75
  76     // Build fake attempt
  77     $timenow = time();
  78     $attempt = new stdClass();
  79     $attempt->quiz = $quiz->id;
  80     $attempt->userid = $USER->id;
  81     $attempt->attempt = 0;
  82     $attempt->sumgrades = 0;
  83     $attempt->timestart = $timenow;
  84     $attempt->timefinish = 0;
  85     $attempt->timemodified = $timenow;
  86     $attempt->uniqueid = 0;
  87     $attempt->id = 0;
  88     $attempt->layout = $question->id;
  89
  90     $options = quiz_get_renderoptions($quiz, $attempt, $context, $state);
  91     $options->noeditlink = true;
  92     // XXX: mulitichoice type needs quiz id to get maxgrade
  93     $options->quizid = 0;
  94
  95     if (!question_check_file_access($question, $state, $options, $context->id, $component,
  96             $filearea, $args, $forcedownload)) {
  97         send_file_not_found();
  98     }
  99
 100     $fs = get_file_storage();
 101     $relativepath = implode('/', $args);
 102     $fullpath = "/$context->id/$component/$filearea/$relativepath";
 103     if (!$file = $fs->get_file_by_hash(sha1($fullpath)) or $file->is_directory()) {
 104         send_file_not_found();
 105     }
 106
 107     send_stored_file($file, 0, 0, $forcedownload);
 108 }