/lib/questionlib.php
PHP | 1349 lines | 740 code | 163 blank | 446 comment | 118 complexity | 717d4bc8403a2b763f4f98fefd91680b MD5 | raw file
- <?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/>.
- /**
- * Code for handling and processing questions
- *
- * This is code that is module independent, i.e., can be used by any module that
- * uses questions, like quiz, lesson, ..
- * This script also loads the questiontype classes
- * Code for handling the editing of questions is in {@link question/editlib.php}
- *
- * TODO: separate those functions which form part of the API
- * from the helper functions.
- *
- * @package moodlecore
- * @subpackage questionbank
- * @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($CFG->dirroot . '/question/engine/lib.php');
- require_once($CFG->dirroot . '/question/type/questiontypebase.php');
- /// CONSTANTS ///////////////////////////////////
- /**
- * Constant determines the number of answer boxes supplied in the editing
- * form for multiple choice and similar question types.
- */
- define("QUESTION_NUMANS", 10);
- /**
- * Constant determines the number of answer boxes supplied in the editing
- * form for multiple choice and similar question types to start with, with
- * the option of adding QUESTION_NUMANS_ADD more answers.
- */
- define("QUESTION_NUMANS_START", 3);
- /**
- * Constant determines the number of answer boxes to add in the editing
- * form for multiple choice and similar question types when the user presses
- * 'add form fields button'.
- */
- define("QUESTION_NUMANS_ADD", 3);
- /**
- * Move one question type in a list of question types. If you try to move one element
- * off of the end, nothing will change.
- *
- * @param array $sortedqtypes An array $qtype => anything.
- * @param string $tomove one of the keys from $sortedqtypes
- * @param integer $direction +1 or -1
- * @return array an array $index => $qtype, with $index from 0 to n in order, and
- * the $qtypes in the same order as $sortedqtypes, except that $tomove will
- * have been moved one place.
- */
- function question_reorder_qtypes($sortedqtypes, $tomove, $direction) {
- $neworder = array_keys($sortedqtypes);
- // Find the element to move.
- $key = array_search($tomove, $neworder);
- if ($key === false) {
- return $neworder;
- }
- // Work out the other index.
- $otherkey = $key + $direction;
- if (!isset($neworder[$otherkey])) {
- return $neworder;
- }
- // Do the swap.
- $swap = $neworder[$otherkey];
- $neworder[$otherkey] = $neworder[$key];
- $neworder[$key] = $swap;
- return $neworder;
- }
- /**
- * Save a new question type order to the config_plugins table.
- * @global object
- * @param $neworder An arra $index => $qtype. Indices should start at 0 and be in order.
- * @param $config get_config('question'), if you happen to have it around, to save one DB query.
- */
- function question_save_qtype_order($neworder, $config = null) {
- global $DB;
- if (is_null($config)) {
- $config = get_config('question');
- }
- foreach ($neworder as $index => $qtype) {
- $sortvar = $qtype . '_sortorder';
- if (!isset($config->$sortvar) || $config->$sortvar != $index + 1) {
- set_config($sortvar, $index + 1, 'question');
- }
- }
- }
- /// FUNCTIONS //////////////////////////////////////////////////////
- /**
- * Returns an array of names of activity modules that use this question
- *
- * @deprecated since Moodle 2.1. Use {@link questions_in_use} instead.
- *
- * @param object $questionid
- * @return array of strings
- */
- function question_list_instances($questionid) {
- throw new coding_exception('question_list_instances has been deprectated. ' .
- 'Please use questions_in_use instead.');
- }
- /**
- * @param array $questionids of question ids.
- * @return boolean whether any of these questions are being used by any part of Moodle.
- */
- function questions_in_use($questionids) {
- global $CFG;
- if (question_engine::questions_in_use($questionids)) {
- return true;
- }
- foreach (get_plugin_list('mod') as $module => $path) {
- $lib = $path . '/lib.php';
- if (is_readable($lib)) {
- include_once($lib);
- $fn = $module . '_questions_in_use';
- if (function_exists($fn)) {
- if ($fn($questionids)) {
- return true;
- }
- } else {
- // Fallback for legacy modules.
- $fn = $module . '_question_list_instances';
- if (function_exists($fn)) {
- foreach ($questionids as $questionid) {
- $instances = $fn($questionid);
- if (!empty($instances)) {
- return true;
- }
- }
- }
- }
- }
- }
- return false;
- }
- /**
- * Determine whether there arey any questions belonging to this context, that is whether any of its
- * question categories contain any questions. This will return true even if all the questions are
- * hidden.
- *
- * @param mixed $context either a context object, or a context id.
- * @return boolean whether any of the question categories beloning to this context have
- * any questions in them.
- */
- function question_context_has_any_questions($context) {
- global $DB;
- if (is_object($context)) {
- $contextid = $context->id;
- } else if (is_numeric($context)) {
- $contextid = $context;
- } else {
- print_error('invalidcontextinhasanyquestions', 'question');
- }
- return $DB->record_exists_sql("SELECT *
- FROM {question} q
- JOIN {question_categories} qc ON qc.id = q.category
- WHERE qc.contextid = ? AND q.parent = 0", array($contextid));
- }
- /**
- * Returns list of 'allowed' grades for grade selection
- * formatted suitably for dropdown box function
- *
- * @deprecated since 2.1. Use {@link question_bank::fraction_options()} or
- * {@link question_bank::fraction_options_full()} instead.
- *
- * @return object ->gradeoptionsfull full array ->gradeoptions +ve only
- */
- function get_grade_options() {
- $grades = new stdClass();
- $grades->gradeoptions = question_bank::fraction_options();
- $grades->gradeoptionsfull = question_bank::fraction_options_full();
- return $grades;
- }
- /**
- * Check whether a given grade is one of a list of allowed options. If not,
- * depending on $matchgrades, either return the nearest match, or return false
- * to signal an error.
- * @param array $gradeoptionsfull list of valid options
- * @param int $grade grade to be tested
- * @param string $matchgrades 'error' or 'nearest'
- * @return mixed either 'fixed' value or false if error.
- */
- function match_grade_options($gradeoptionsfull, $grade, $matchgrades = 'error') {
- if ($matchgrades == 'error') {
- // (Almost) exact match, or an error.
- foreach ($gradeoptionsfull as $value => $option) {
- // Slightly fuzzy test, never check floats for equality.
- if (abs($grade - $value) < 0.00001) {
- return $value; // Be sure the return the proper value.
- }
- }
- // Didn't find a match so that's an error.
- return false;
- } else if ($matchgrades == 'nearest') {
- // Work out nearest value
- $best = false;
- $bestmismatch = 2;
- foreach ($gradeoptionsfull as $value => $option) {
- $newmismatch = abs($grade - $value);
- if ($newmismatch < $bestmismatch) {
- $best = $value;
- $bestmismatch = $newmismatch;
- }
- }
- return $best;
- } else {
- // Unknow option passed.
- throw new coding_exception('Unknown $matchgrades ' . $matchgrades .
- ' passed to match_grade_options');
- }
- }
- /**
- * @deprecated Since Moodle 2.1. Use {@link question_category_in_use} instead.
- * @param integer $categoryid a question category id.
- * @param boolean $recursive whether to check child categories too.
- * @return boolean whether any question in this category is in use.
- */
- function question_category_isused($categoryid, $recursive = false) {
- throw new coding_exception('question_category_isused has been deprectated. ' .
- 'Please use question_category_in_use instead.');
- }
- /**
- * Tests whether any question in a category is used by any part of Moodle.
- *
- * @param integer $categoryid a question category id.
- * @param boolean $recursive whether to check child categories too.
- * @return boolean whether any question in this category is in use.
- */
- function question_category_in_use($categoryid, $recursive = false) {
- global $DB;
- //Look at each question in the category
- if ($questions = $DB->get_records_menu('question',
- array('category' => $categoryid), '', 'id, 1')) {
- if (questions_in_use(array_keys($questions))) {
- return true;
- }
- }
- if (!$recursive) {
- return false;
- }
- //Look under child categories recursively
- if ($children = $DB->get_records('question_categories',
- array('parent' => $categoryid), '', 'id, 1')) {
- foreach ($children as $child) {
- if (question_category_in_use($child->id, $recursive)) {
- return true;
- }
- }
- }
- return false;
- }
- /**
- * Deletes question and all associated data from the database
- *
- * It will not delete a question if it is used by an activity module
- * @param object $question The question being deleted
- */
- function question_delete_question($questionid) {
- global $DB;
- $question = $DB->get_record_sql('
- SELECT q.*, qc.contextid
- FROM {question} q
- JOIN {question_categories} qc ON qc.id = q.category
- WHERE q.id = ?', array($questionid));
- if (!$question) {
- // In some situations, for example if this was a child of a
- // Cloze question that was previously deleted, the question may already
- // have gone. In this case, just do nothing.
- return;
- }
- // Do not delete a question if it is used by an activity module
- if (questions_in_use(array($questionid))) {
- return;
- }
- // Check permissions.
- question_require_capability_on($question, 'edit');
- $dm = new question_engine_data_mapper();
- $dm->delete_previews($questionid);
- // delete questiontype-specific data
- question_bank::get_qtype($question->qtype, false)->delete_question(
- $questionid, $question->contextid);
- // Now recursively delete all child questions
- if ($children = $DB->get_records('question',
- array('parent' => $questionid), '', 'id, qtype')) {
- foreach ($children as $child) {
- if ($child->id != $questionid) {
- question_delete_question($child->id);
- }
- }
- }
- // Finally delete the question record itself
- $DB->delete_records('question', array('id' => $questionid));
- question_bank::notify_question_edited($questionid);
- }
- /**
- * All question categories and their questions are deleted for this course.
- *
- * @param stdClass $course an object representing the activity
- * @param boolean $feedback to specify if the process must output a summary of its work
- * @return boolean
- */
- function question_delete_course($course, $feedback=true) {
- global $DB, $OUTPUT;
- //To store feedback to be showed at the end of the process
- $feedbackdata = array();
- //Cache some strings
- $strcatdeleted = get_string('unusedcategorydeleted', 'quiz');
- $coursecontext = context_course::instance($course->id);
- $categoriescourse = $DB->get_records('question_categories',
- array('contextid' => $coursecontext->id), 'parent', 'id, parent, name, contextid');
- if ($categoriescourse) {
- //Sort categories following their tree (parent-child) relationships
- //this will make the feedback more readable
- $categoriescourse = sort_categories_by_tree($categoriescourse);
- foreach ($categoriescourse as $category) {
- //Delete it completely (questions and category itself)
- //deleting questions
- if ($questions = $DB->get_records('question',
- array('category' => $category->id), '', 'id,qtype')) {
- foreach ($questions as $question) {
- question_delete_question($question->id);
- }
- $DB->delete_records("question", array("category" => $category->id));
- }
- //delete the category
- $DB->delete_records('question_categories', array('id' => $category->id));
- //Fill feedback
- $feedbackdata[] = array($category->name, $strcatdeleted);
- }
- //Inform about changes performed if feedback is enabled
- if ($feedback) {
- $table = new html_table();
- $table->head = array(get_string('category', 'quiz'), get_string('action'));
- $table->data = $feedbackdata;
- echo html_writer::table($table);
- }
- }
- return true;
- }
- /**
- * Category is about to be deleted,
- * 1/ All question categories and their questions are deleted for this course category.
- * 2/ All questions are moved to new category
- *
- * @param object|coursecat $category course category object
- * @param object|coursecat $newcategory empty means everything deleted, otherwise id of
- * category where content moved
- * @param boolean $feedback to specify if the process must output a summary of its work
- * @return boolean
- */
- function question_delete_course_category($category, $newcategory, $feedback=true) {
- global $DB, $OUTPUT;
- $context = context_coursecat::instance($category->id);
- if (empty($newcategory)) {
- $feedbackdata = array(); // To store feedback to be showed at the end of the process
- $rescueqcategory = null; // See the code around the call to question_save_from_deletion.
- $strcatdeleted = get_string('unusedcategorydeleted', 'quiz');
- // Loop over question categories.
- if ($categories = $DB->get_records('question_categories',
- array('contextid'=>$context->id), 'parent', 'id, parent, name')) {
- foreach ($categories as $category) {
- // Deal with any questions in the category.
- if ($questions = $DB->get_records('question',
- array('category' => $category->id), '', 'id,qtype')) {
- // Try to delete each question.
- foreach ($questions as $question) {
- question_delete_question($question->id);
- }
- // Check to see if there were any questions that were kept because
- // they are still in use somehow, even though quizzes in courses
- // in this category will already have been deteted. This could
- // happen, for example, if questions are added to a course,
- // and then that course is moved to another category (MDL-14802).
- $questionids = $DB->get_records_menu('question',
- array('category'=>$category->id), '', 'id, 1');
- if (!empty($questionids)) {
- if (!$rescueqcategory = question_save_from_deletion(
- array_keys($questionids), get_parent_contextid($context),
- print_context_name($context), $rescueqcategory)) {
- return false;
- }
- $feedbackdata[] = array($category->name,
- get_string('questionsmovedto', 'question', $rescueqcategory->name));
- }
- }
- // Now delete the category.
- if (!$DB->delete_records('question_categories', array('id'=>$category->id))) {
- return false;
- }
- $feedbackdata[] = array($category->name, $strcatdeleted);
- } // End loop over categories.
- }
- // Output feedback if requested.
- if ($feedback and $feedbackdata) {
- $table = new html_table();
- $table->head = array(get_string('questioncategory', 'question'), get_string('action'));
- $table->data = $feedbackdata;
- echo html_writer::table($table);
- }
- } else {
- // Move question categories ot the new context.
- if (!$newcontext = context_coursecat::instance($newcategory->id)) {
- return false;
- }
- $DB->set_field('question_categories', 'contextid', $newcontext->id,
- array('contextid'=>$context->id));
- if ($feedback) {
- $a = new stdClass();
- $a->oldplace = print_context_name($context);
- $a->newplace = print_context_name($newcontext);
- echo $OUTPUT->notification(
- get_string('movedquestionsandcategories', 'question', $a), 'notifysuccess');
- }
- }
- return true;
- }
- /**
- * Enter description here...
- *
- * @param array $questionids of question ids
- * @param object $newcontext the context to create the saved category in.
- * @param string $oldplace a textual description of the think being deleted,
- * e.g. from get_context_name
- * @param object $newcategory
- * @return mixed false on
- */
- function question_save_from_deletion($questionids, $newcontextid, $oldplace,
- $newcategory = null) {
- global $DB;
- // Make a category in the parent context to move the questions to.
- if (is_null($newcategory)) {
- $newcategory = new stdClass();
- $newcategory->parent = 0;
- $newcategory->contextid = $newcontextid;
- $newcategory->name = get_string('questionsrescuedfrom', 'question', $oldplace);
- $newcategory->info = get_string('questionsrescuedfrominfo', 'question', $oldplace);
- $newcategory->sortorder = 999;
- $newcategory->stamp = make_unique_id_code();
- $newcategory->id = $DB->insert_record('question_categories', $newcategory);
- }
- // Move any remaining questions to the 'saved' category.
- if (!question_move_questions_to_category($questionids, $newcategory->id)) {
- return false;
- }
- return $newcategory;
- }
- /**
- * All question categories and their questions are deleted for this activity.
- *
- * @param object $cm the course module object representing the activity
- * @param boolean $feedback to specify if the process must output a summary of its work
- * @return boolean
- */
- function question_delete_activity($cm, $feedback=true) {
- global $DB, $OUTPUT;
- //To store feedback to be showed at the end of the process
- $feedbackdata = array();
- //Cache some strings
- $strcatdeleted = get_string('unusedcategorydeleted', 'quiz');
- $modcontext = context_module::instance($cm->id);
- if ($categoriesmods = $DB->get_records('question_categories',
- array('contextid' => $modcontext->id), 'parent', 'id, parent, name, contextid')) {
- //Sort categories following their tree (parent-child) relationships
- //this will make the feedback more readable
- $categoriesmods = sort_categories_by_tree($categoriesmods);
- foreach ($categoriesmods as $category) {
- //Delete it completely (questions and category itself)
- //deleting questions
- if ($questions = $DB->get_records('question',
- array('category' => $category->id), '', 'id,qtype')) {
- foreach ($questions as $question) {
- question_delete_question($question->id);
- }
- $DB->delete_records("question", array("category"=>$category->id));
- }
- //delete the category
- $DB->delete_records('question_categories', array('id'=>$category->id));
- //Fill feedback
- $feedbackdata[] = array($category->name, $strcatdeleted);
- }
- //Inform about changes performed if feedback is enabled
- if ($feedback) {
- $table = new html_table();
- $table->head = array(get_string('category', 'quiz'), get_string('action'));
- $table->data = $feedbackdata;
- echo html_writer::table($table);
- }
- }
- return true;
- }
- /**
- * This function should be considered private to the question bank, it is called from
- * question/editlib.php question/contextmoveq.php and a few similar places to to the
- * work of acutally moving questions and associated data. However, callers of this
- * function also have to do other work, which is why you should not call this method
- * directly from outside the questionbank.
- *
- * @param array $questionids of question ids.
- * @param integer $newcategoryid the id of the category to move to.
- */
- function question_move_questions_to_category($questionids, $newcategoryid) {
- global $DB;
- $newcontextid = $DB->get_field('question_categories', 'contextid',
- array('id' => $newcategoryid));
- list($questionidcondition, $params) = $DB->get_in_or_equal($questionids);
- $questions = $DB->get_records_sql("
- SELECT q.id, q.qtype, qc.contextid
- FROM {question} q
- JOIN {question_categories} qc ON q.category = qc.id
- WHERE q.id $questionidcondition", $params);
- foreach ($questions as $question) {
- if ($newcontextid != $question->contextid) {
- question_bank::get_qtype($question->qtype)->move_files(
- $question->id, $question->contextid, $newcontextid);
- }
- }
- // Move the questions themselves.
- $DB->set_field_select('question', 'category', $newcategoryid,
- "id $questionidcondition", $params);
- // Move any subquestions belonging to them.
- $DB->set_field_select('question', 'category', $newcategoryid,
- "parent $questionidcondition", $params);
- // TODO Deal with datasets.
- // Purge these questions from the cache.
- foreach ($questions as $question) {
- question_bank::notify_question_edited($question->id);
- }
- return true;
- }
- /**
- * This function helps move a question cateogry to a new context by moving all
- * the files belonging to all the questions to the new context.
- * Also moves subcategories.
- * @param integer $categoryid the id of the category being moved.
- * @param integer $oldcontextid the old context id.
- * @param integer $newcontextid the new context id.
- */
- function question_move_category_to_context($categoryid, $oldcontextid, $newcontextid) {
- global $DB;
- $questionids = $DB->get_records_menu('question',
- array('category' => $categoryid), '', 'id,qtype');
- foreach ($questionids as $questionid => $qtype) {
- question_bank::get_qtype($qtype)->move_files(
- $questionid, $oldcontextid, $newcontextid);
- // Purge this question from the cache.
- question_bank::notify_question_edited($questionid);
- }
- $subcatids = $DB->get_records_menu('question_categories',
- array('parent' => $categoryid), '', 'id,1');
- foreach ($subcatids as $subcatid => $notused) {
- $DB->set_field('question_categories', 'contextid', $newcontextid,
- array('id' => $subcatid));
- question_move_category_to_context($subcatid, $oldcontextid, $newcontextid);
- }
- }
- /**
- * Generate the URL for starting a new preview of a given question with the given options.
- * @param integer $questionid the question to preview.
- * @param string $preferredbehaviour the behaviour to use for the preview.
- * @param float $maxmark the maximum to mark the question out of.
- * @param question_display_options $displayoptions the display options to use.
- * @param int $variant the variant of the question to preview. If null, one will
- * be picked randomly.
- * @param object $context context to run the preview in (affects things like
- * filter settings, theme, lang, etc.) Defaults to $PAGE->context.
- * @return string the URL.
- */
- function question_preview_url($questionid, $preferredbehaviour = null,
- $maxmark = null, $displayoptions = null, $variant = null, $context = null) {
- $params = array('id' => $questionid);
- if (is_null($context)) {
- global $PAGE;
- $context = $PAGE->context;
- }
- if ($context->contextlevel == CONTEXT_MODULE) {
- $params['cmid'] = $context->instanceid;
- } else if ($context->contextlevel == CONTEXT_COURSE) {
- $params['courseid'] = $context->instanceid;
- }
- if (!is_null($preferredbehaviour)) {
- $params['behaviour'] = $preferredbehaviour;
- }
- if (!is_null($maxmark)) {
- $params['maxmark'] = $maxmark;
- }
- if (!is_null($displayoptions)) {
- $params['correctness'] = $displayoptions->correctness;
- $params['marks'] = $displayoptions->marks;
- $params['markdp'] = $displayoptions->markdp;
- $params['feedback'] = (bool) $displayoptions->feedback;
- $params['generalfeedback'] = (bool) $displayoptions->generalfeedback;
- $params['rightanswer'] = (bool) $displayoptions->rightanswer;
- $params['history'] = (bool) $displayoptions->history;
- }
- if ($variant) {
- $params['variant'] = $variant;
- }
- return new moodle_url('/question/preview.php', $params);
- }
- /**
- * @return array that can be passed as $params to the {@link popup_action} constructor.
- */
- function question_preview_popup_params() {
- return array(
- 'height' => 600,
- 'width' => 800,
- );
- }
- /**
- * Given a list of ids, load the basic information about a set of questions from
- * the questions table. The $join and $extrafields arguments can be used together
- * to pull in extra data. See, for example, the usage in mod/quiz/attemptlib.php, and
- * read the code below to see how the SQL is assembled. Throws exceptions on error.
- *
- * @global object
- * @global object
- * @param array $questionids array of question ids.
- * @param string $extrafields extra SQL code to be added to the query.
- * @param string $join extra SQL code to be added to the query.
- * @param array $extraparams values for any placeholders in $join.
- * You are strongly recommended to use named placeholder.
- *
- * @return array partially complete question objects. You need to call get_question_options
- * on them before they can be properly used.
- */
- function question_preload_questions($questionids, $extrafields = '', $join = '',
- $extraparams = array()) {
- global $DB;
- if (empty($questionids)) {
- return array();
- }
- if ($join) {
- $join = ' JOIN '.$join;
- }
- if ($extrafields) {
- $extrafields = ', ' . $extrafields;
- }
- list($questionidcondition, $params) = $DB->get_in_or_equal(
- $questionids, SQL_PARAMS_NAMED, 'qid0000');
- $sql = 'SELECT q.*, qc.contextid' . $extrafields . ' FROM {question} q
- JOIN {question_categories} qc ON q.category = qc.id' .
- $join .
- ' WHERE q.id ' . $questionidcondition;
- // Load the questions
- if (!$questions = $DB->get_records_sql($sql, $extraparams + $params)) {
- return array();
- }
- foreach ($questions as $question) {
- $question->_partiallyloaded = true;
- }
- // Note, a possible optimisation here would be to not load the TEXT fields
- // (that is, questiontext and generalfeedback) here, and instead load them in
- // question_load_questions. That would add one DB query, but reduce the amount
- // of data transferred most of the time. I am not going to do this optimisation
- // until it is shown to be worthwhile.
- return $questions;
- }
- /**
- * Load a set of questions, given a list of ids. The $join and $extrafields arguments can be used
- * together to pull in extra data. See, for example, the usage in mod/quiz/attempt.php, and
- * read the code below to see how the SQL is assembled. Throws exceptions on error.
- *
- * @param array $questionids array of question ids.
- * @param string $extrafields extra SQL code to be added to the query.
- * @param string $join extra SQL code to be added to the query.
- * @param array $extraparams values for any placeholders in $join.
- * You are strongly recommended to use named placeholder.
- *
- * @return array question objects.
- */
- function question_load_questions($questionids, $extrafields = '', $join = '') {
- $questions = question_preload_questions($questionids, $extrafields, $join);
- // Load the question type specific information
- if (!get_question_options($questions)) {
- return 'Could not load the question options';
- }
- return $questions;
- }
- /**
- * Private function to factor common code out of get_question_options().
- *
- * @param object $question the question to tidy.
- * @param boolean $loadtags load the question tags from the tags table. Optional, default false.
- */
- function _tidy_question($question, $loadtags = false) {
- global $CFG;
- // Load question-type specific fields.
- if (!question_bank::is_qtype_installed($question->qtype)) {
- $question->questiontext = html_writer::tag('p', get_string('warningmissingtype',
- 'qtype_missingtype')) . $question->questiontext;
- }
- question_bank::get_qtype($question->qtype)->get_question_options($question);
- // Convert numeric fields to float. (Prevents these being displayed as 1.0000000.)
- $question->defaultmark += 0;
- $question->penalty += 0;
- if (isset($question->_partiallyloaded)) {
- unset($question->_partiallyloaded);
- }
- if ($loadtags && !empty($CFG->usetags)) {
- require_once($CFG->dirroot . '/tag/lib.php');
- $question->tags = tag_get_tags_array('question', $question->id);
- }
- }
- /**
- * Updates the question objects with question type specific
- * information by calling {@link get_question_options()}
- *
- * Can be called either with an array of question objects or with a single
- * question object.
- *
- * @param mixed $questions Either an array of question objects to be updated
- * or just a single question object
- * @param boolean $loadtags load the question tags from the tags table. Optional, default false.
- * @return bool Indicates success or failure.
- */
- function get_question_options(&$questions, $loadtags = false) {
- if (is_array($questions)) { // deal with an array of questions
- foreach ($questions as $i => $notused) {
- _tidy_question($questions[$i], $loadtags);
- }
- } else { // deal with single question
- _tidy_question($questions, $loadtags);
- }
- return true;
- }
- /**
- * Print the icon for the question type
- *
- * @param object $question The question object for which the icon is required.
- * Only $question->qtype is used.
- * @return string the HTML for the img tag.
- */
- function print_question_icon($question) {
- global $PAGE;
- return $PAGE->get_renderer('question', 'bank')->qtype_icon($question->qtype);
- }
- /**
- * Creates a stamp that uniquely identifies this version of the question
- *
- * In future we want this to use a hash of the question data to guarantee that
- * identical versions have the same version stamp.
- *
- * @param object $question
- * @return string A unique version stamp
- */
- function question_hash($question) {
- return make_unique_id_code();
- }
- /// FUNCTIONS THAT SIMPLY WRAP QUESTIONTYPE METHODS //////////////////////////////////
- /**
- * Saves question options
- *
- * Simply calls the question type specific save_question_options() method.
- * @deprecated all code should now call the question type method directly.
- */
- function save_question_options($question) {
- debugging('Please do not call save_question_options any more. Call the question type method directly.',
- DEBUG_DEVELOPER);
- question_bank::get_qtype($question->qtype)->save_question_options($question);
- }
- /// CATEGORY FUNCTIONS /////////////////////////////////////////////////////////////////
- /**
- * returns the categories with their names ordered following parent-child relationships
- * finally it tries to return pending categories (those being orphaned, whose parent is
- * incorrect) to avoid missing any category from original array.
- */
- function sort_categories_by_tree(&$categories, $id = 0, $level = 1) {
- global $DB;
- $children = array();
- $keys = array_keys($categories);
- foreach ($keys as $key) {
- if (!isset($categories[$key]->processed) && $categories[$key]->parent == $id) {
- $children[$key] = $categories[$key];
- $categories[$key]->processed = true;
- $children = $children + sort_categories_by_tree(
- $categories, $children[$key]->id, $level+1);
- }
- }
- //If level = 1, we have finished, try to look for non processed categories
- // (bad parent) and sort them too
- if ($level == 1) {
- foreach ($keys as $key) {
- // If not processed and it's a good candidate to start (because its
- // parent doesn't exist in the course)
- if (!isset($categories[$key]->processed) && !$DB->record_exists('question_categories',
- array('contextid' => $categories[$key]->contextid,
- 'id' => $categories[$key]->parent))) {
- $children[$key] = $categories[$key];
- $categories[$key]->processed = true;
- $children = $children + sort_categories_by_tree(
- $categories, $children[$key]->id, $level + 1);
- }
- }
- }
- return $children;
- }
- /**
- * Private method, only for the use of add_indented_names().
- *
- * Recursively adds an indentedname field to each category, starting with the category
- * with id $id, and dealing with that category and all its children, and
- * return a new array, with those categories in the right order.
- *
- * @param array $categories an array of categories which has had childids
- * fields added by flatten_category_tree(). Passed by reference for
- * performance only. It is not modfied.
- * @param int $id the category to start the indenting process from.
- * @param int $depth the indent depth. Used in recursive calls.
- * @return array a new array of categories, in the right order for the tree.
- */
- function flatten_category_tree(&$categories, $id, $depth = 0, $nochildrenof = -1) {
- // Indent the name of this category.
- $newcategories = array();
- $newcategories[$id] = $categories[$id];
- $newcategories[$id]->indentedname = str_repeat(' ', $depth) .
- $categories[$id]->name;
- // Recursively indent the children.
- foreach ($categories[$id]->childids as $childid) {
- if ($childid != $nochildrenof) {
- $newcategories = $newcategories + flatten_category_tree(
- $categories, $childid, $depth + 1, $nochildrenof);
- }
- }
- // Remove the childids array that were temporarily added.
- unset($newcategories[$id]->childids);
- return $newcategories;
- }
- /**
- * Format categories into an indented list reflecting the tree structure.
- *
- * @param array $categories An array of category objects, for example from the.
- * @return array The formatted list of categories.
- */
- function add_indented_names($categories, $nochildrenof = -1) {
- // Add an array to each category to hold the child category ids. This array
- // will be removed again by flatten_category_tree(). It should not be used
- // outside these two functions.
- foreach (array_keys($categories) as $id) {
- $categories[$id]->childids = array();
- }
- // Build the tree structure, and record which categories are top-level.
- // We have to be careful, because the categories array may include published
- // categories from other courses, but not their parents.
- $toplevelcategoryids = array();
- foreach (array_keys($categories) as $id) {
- if (!empty($categories[$id]->parent) &&
- array_key_exists($categories[$id]->parent, $categories)) {
- $categories[$categories[$id]->parent]->childids[] = $id;
- } else {
- $toplevelcategoryids[] = $id;
- }
- }
- // Flatten the tree to and add the indents.
- $newcategories = array();
- foreach ($toplevelcategoryids as $id) {
- $newcategories = $newcategories + flatten_category_tree(
- $categories, $id, 0, $nochildrenof);
- }
- return $newcategories;
- }
- /**
- * Output a select menu of question categories.
- *
- * Categories from this course and (optionally) published categories from other courses
- * are included. Optionally, only categories the current user may edit can be included.
- *
- * @param integer $courseid the id of the course to get the categories for.
- * @param integer $published if true, include publised categories from other courses.
- * @param integer $only_editable if true, exclude categories this user is not allowed to edit.
- * @param integer $selected optionally, the id of a category to be selected by
- * default in the dropdown.
- */
- function question_category_select_menu($contexts, $top = false, $currentcat = 0,
- $selected = "", $nochildrenof = -1) {
- global $OUTPUT;
- $categoriesarray = question_category_options($contexts, $top, $currentcat,
- false, $nochildrenof);
- if ($selected) {
- $choose = '';
- } else {
- $choose = 'choosedots';
- }
- $options = array();
- foreach ($categoriesarray as $group => $opts) {
- $options[] = array($group => $opts);
- }
- echo html_writer::label($selected, 'menucategory', false, array('class' => 'accesshide'));
- echo html_writer::select($options, 'category', $selected, $choose);
- }
- /**
- * @param integer $contextid a context id.
- * @return object the default question category for that context, or false if none.
- */
- function question_get_default_category($contextid) {
- global $DB;
- $category = $DB->get_records('question_categories',
- array('contextid' => $contextid), 'id', '*', 0, 1);
- if (!empty($category)) {
- return reset($category);
- } else {
- return false;
- }
- }
- /**
- * Gets the default category in the most specific context.
- * If no categories exist yet then default ones are created in all contexts.
- *
- * @param array $contexts The context objects for this context and all parent contexts.
- * @return object The default category - the category in the course context
- */
- function question_make_default_categories($contexts) {
- global $DB;
- static $preferredlevels = array(
- CONTEXT_COURSE => 4,
- CONTEXT_MODULE => 3,
- CONTEXT_COURSECAT => 2,
- CONTEXT_SYSTEM => 1,
- );
- $toreturn = null;
- $preferredness = 0;
- // If it already exists, just return it.
- foreach ($contexts as $key => $context) {
- if (!$exists = $DB->record_exists("question_categories",
- array('contextid' => $context->id))) {
- // Otherwise, we need to make one
- $category = new stdClass();
- $contextname = print_context_name($context, false, true);
- $category->name = get_string('defaultfor', 'question', $contextname);
- $category->info = get_string('defaultinfofor', 'question', $contextname);
- $category->contextid = $context->id;
- $category->parent = 0;
- // By default, all categories get this number, and are sorted alphabetically.
- $category->sortorder = 999;
- $category->stamp = make_unique_id_code();
- $category->id = $DB->insert_record('question_categories', $category);
- } else {
- $category = question_get_default_category($context->id);
- }
- $thispreferredness = $preferredlevels[$context->contextlevel];
- if (has_any_capability(array('moodle/question:usemine', 'moodle/question:useall'), $context)) {
- $thispreferredness += 10;
- }
- if ($thispreferredness > $preferredness) {
- $toreturn = $category;
- $preferredness = $thispreferredness;
- }
- }
- if (!is_null($toreturn)) {
- $toreturn = clone($toreturn);
- }
- return $toreturn;
- }
- /**
- * Get all the category objects, including a count of the number of questions in that category,
- * for all the categories in the lists $contexts.
- *
- * @param mixed $contexts either a single contextid, or a comma-separated list of context ids.
- * @param string $sortorder used as the ORDER BY clause in the select statement.
- * @return array of category objects.
- */
- function get_categories_for_contexts($contexts, $sortorder = 'parent, sortorder, name ASC') {
- global $DB;
- return $DB->get_records_sql("
- SELECT c.*, (SELECT count(1) FROM {question} q
- WHERE c.id = q.category AND q.hidden='0' AND q.parent='0') AS questioncount
- FROM {question_categories} c
- WHERE c.contextid IN ($contexts)
- ORDER BY $sortorder");
- }
- /**
- * Output an array of question categories.
- */
- function question_category_options($contexts, $top = false, $currentcat = 0,
- $popupform = false, $nochildrenof = -1) {
- global $CFG;
- $pcontexts = array();
- foreach ($contexts as $context) {
- $pcontexts[] = $context->id;
- }
- $contextslist = join($pcontexts, ', ');
- $categories = get_categories_for_contexts($contextslist);
- $categories = question_add_context_in_key($categories);
- if ($top) {
- $categories = question_add_tops($categories, $pcontexts);
- }
- $categories = add_indented_names($categories, $nochildrenof);
- // sort cats out into different contexts
- $categoriesarray = array();
- foreach ($pcontexts as $contextid) {
- $context = context::instance_by_id($contextid);
- $contextstring = $context->get_context_name(true, true);
- foreach ($categories as $category) {
- if ($category->contextid == $contextid) {
- $cid = $category->id;
- if ($currentcat != $cid || $currentcat == 0) {
- $countstring = !empty($category->questioncount) ?
- " ($category->questioncount)" : '';
- $categoriesarray[$contextstring][$cid] =
- format_string($category->indentedname, true,
- array('context' => $context)) . $countstring;
- }
- }
- }
- }
- if ($popupform) {
- $popupcats = array();
- foreach ($categoriesarray as $contextstring => $optgroup) {
- $group = array();
- foreach ($optgroup as $key => $value) {
- $key = str_replace($CFG->wwwroot, '', $key);
- $group[$key] = $value;
- }
- $popupcats[] = array($contextstring => $group);
- }
- return $popupcats;
- } else {
- return $categoriesarray;
- }
- }
- function question_add_context_in_key($categories) {
- $newcatarray = array();
- foreach ($categories as $id => $category) {
- $category->parent = "$category->parent,$category->contextid";
- $category->id = "$category->id,$category->contextid";
- $newcatarray["$id,$category->contextid"] = $category;
- }
- return $newcatarray;
- }
- function question_add_tops($categories, $pcontexts) {
- $topcats = array();
- foreach ($pcontexts as $context) {
- $newcat = new stdClass();
- $newcat->id = "0,$context";
- $newcat->name = get_string('top');
- $newcat->parent = -1;
- $newcat->contextid = $context;
- $topcats["0,$context"] = $newcat;
- }
- //put topcats in at beginning of array - they'll be sorted into different contexts later.
- return array_merge($topcats, $categories);
- }
- /**
- * @return array of question category ids of the category and all subcategories.
- */
- function question_categorylist($categoryid) {
- global $DB;
- // final list of category IDs
- $categorylist = array();
- // a list of category IDs to check for any sub-categories
- $subcategories = array($categoryid);
- while ($subcategories) {
- foreach ($subcategories as $subcategory) {
- // if anything from the temporary list was added already, then we have a loop
- if (isset($categorylist[$subcategory])) {
- throw new coding_exception("Category id=$subcategory is already on the list - loop of categories detected.");
- }
- $categorylist[$subcategory] = $subcategory;
- }
- list ($in, $params) = $DB->get_in_or_equal($subcategories);
- $subcategories = $DB->get_records_select_menu('question_categories',
- "parent $in", $params, NULL, 'id,id AS id2');
- }
- return $categorylist;
- }
- //===========================
- // Import/Export Functions
- //===========================
- /**
- * Get list of available import or export formats
- * @param string $type 'import' if import list, otherwise export list assumed
- * @return array sorted list of import/export formats available
- */
- function get_import_export_formats($type) {
- global $CFG;
- require_once($CFG->dirroot . '/question/format.php');
- $formatclasses = get_plugin_list_with_class('qformat', '', 'format.php');
- $fileformatname = array();
- foreach ($formatclasses as $component => $formatclass) {
- $format = new $formatclass();
- if ($type == 'import') {
- $provided = $format->provide_import();
- } else {
- $provided = $format->provide_export();
- }
- if ($provided) {
- list($notused, $fileformat) = explode('_', $component, 2);
- $fileformatnames[$fileformat] = get_string('pluginname', $component);
- }
- }
- collatorlib::asort($fileformatnames);
- return $fileformatnames;
- }
- /**
- * Create a reasonable default file name for exporting questions from a particular
- * category.
- * @param object $course the course the questions are in.
- * @param object $category the question category.
- * @return string the filename.
- */
- function question_default_export_filename($course, $category) {
- // We build a string that is an appropriate name (questions) from the lang pack,
- // then the corse shortname, then the question category name, then a timestamp.
- $base = clean_filename(get_string('exportfilename', 'question'));
- $dateformat = str_replace(' ', '_', get_string('exportnameformat', 'question'));
- $timestamp = clean_filename(userdate(time(), $dateformat, 99, false));
- $shortname = clean_filename($course->shortname);
- if ($shortname == '' || $shortname == '_' ) {
- $shortname = $course->id;
- }
- $categoryname = clean_filename(format_string($category->name));
- return "{$base}-{$shortname}-{$categoryname}-{$timestamp}";
- return $export_name;
- }
- /**
- * Converts contextlevels to strings and back to help with reading/writing contexts
- * to/from import/export files.
- *
- * @copyright 1999 onwards Martin Dougiamas {@link http://moodle.com}
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- class context_to_string_translator{
- /**
- * @var array used to translate between contextids and strings for this context.
- */
- protected $contexttostringarray = array();
- public function __construct($contexts) {
- $this->generate_context_to_string_array($contexts);
- }
- public function context_to_string($contextid) {
- return $this->contexttostringarray[$contextid];
- }
- public function string_to_context($contextname) {
- $contextid = array_search($contextname, $this->contexttostringarray);
- return $contextid;
- }
- protected function generate_context_to_string_array($contexts) {
- if (!$this->contexttostringarray) {
- $catno = 1;
- foreach ($contexts as $context) {
- switch ($context->contextlevel) {
- case CONTEXT_MODULE :
- $contextstring = 'module';
- break;
- case CONTEXT_COURSE :
- $contextstring = 'course';
- break;
- case CONTEXT_COURSECAT :
- $contextstring = "cat$catno";
- $catno++;
- break;
- case CONTEXT_SYSTEM :
- $contextstring = 'system';
- break;
- }
- $this->contexttostringarray[$context->id] = $contextstring;
- }
- }
- }
- }
- /**
- * Check capability on category
- *
- * @param mixed $question object or id
- * @param string $cap 'add', 'edit', 'view', 'use', 'move'
- * @param integer $cachecat useful to cache all question records in a category
- * @return boolean this user has the capability $cap for this question $question?
- */
- function question_has_capability_on($question, $cap, $cachecat = -1) {
- global $USER, $DB;
- // these are capabilities on existing questions capabilties are
- //set per category. Each of these has a mine and all version. Append 'mine' and 'all'
- $question_questioncaps = array('edit', 'view', 'use', 'move');
- static $questions = array();
- static $categories = array();
- static $cachedcat = arr