MDL-61410 question: support course tags on export
[moodle.git] / question / format / xml / format.php
1 <?php
2 // This file is part of Moodle - http://moodle.org/
3 //
4 // Moodle is free software: you can redistribute it and/or modify
5 // it under the terms of the GNU General Public License as published by
6 // the Free Software Foundation, either version 3 of the License, or
7 // (at your option) any later version.
8 //
9 // Moodle is distributed in the hope that it will be useful,
10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12 // GNU General Public License for more details.
13 //
14 // You should have received a copy of the GNU General Public License
15 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
17 /**
18  * Code for exporting questions as Moodle XML.
19  *
20  * @package    qformat_xml
21  * @copyright  1999 onwards Martin Dougiamas {@link http://moodle.com}
22  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
23  */
26 defined('MOODLE_INTERNAL') || die();
28 require_once($CFG->libdir . '/xmlize.php');
29 if (!class_exists('qformat_default')) {
30     // This is ugly, but this class is also (ab)used by mod/lesson, which defines
31     // a different base class in mod/lesson/format.php. Thefore, we can only
32     // include the proper base class conditionally like this. (We have to include
33     // the base class like this, otherwise it breaks third-party question types.)
34     // This may be reviewd, and a better fix found one day.
35     require_once($CFG->dirroot . '/question/format.php');
36 }
39 /**
40  * Importer for Moodle XML question format.
41  *
42  * See http://docs.moodle.org/en/Moodle_XML_format for a description of the format.
43  *
44  * @copyright  1999 onwards Martin Dougiamas {@link http://moodle.com}
45  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
46  */
47 class qformat_xml extends qformat_default {
49     public function provide_import() {
50         return true;
51     }
53     public function provide_export() {
54         return true;
55     }
57     public function mime_type() {
58         return 'application/xml';
59     }
61     // IMPORT FUNCTIONS START HERE.
63     /**
64      * Translate human readable format name
65      * into internal Moodle code number
66      * @param string name format name from xml file
67      * @return int Moodle format code
68      */
69     public function trans_format($name) {
70         $name = trim($name);
72         if ($name == 'moodle_auto_format') {
73             return FORMAT_MOODLE;
74         } else if ($name == 'html') {
75             return FORMAT_HTML;
76         } else if ($name == 'plain_text') {
77             return FORMAT_PLAIN;
78         } else if ($name == 'wiki_like') {
79             return FORMAT_WIKI;
80         } else if ($name == 'markdown') {
81             return FORMAT_MARKDOWN;
82         } else {
83             debugging("Unrecognised text format '{$name}' in the import file. Assuming 'html'.");
84             return FORMAT_HTML;
85         }
86     }
88     /**
89      * Translate human readable single answer option
90      * to internal code number
91      * @param string name true/false
92      * @return int internal code number
93      */
94     public function trans_single($name) {
95         $name = trim($name);
96         if ($name == "false" || !$name) {
97             return 0;
98         } else {
99             return 1;
100         }
101     }
103     /**
104      * process text string from xml file
105      * @param array $text bit of xml tree after ['text']
106      * @return string processed text.
107      */
108     public function import_text($text) {
109         // Quick sanity check.
110         if (empty($text)) {
111             return '';
112         }
113         $data = $text[0]['#'];
114         return trim($data);
115     }
117     /**
118      * return the value of a node, given a path to the node
119      * if it doesn't exist return the default value
120      * @param array xml data to read
121      * @param array path path to node expressed as array
122      * @param mixed default
123      * @param bool istext process as text
124      * @param string error if set value must exist, return false and issue message if not
125      * @return mixed value
126      */
127     public function getpath($xml, $path, $default, $istext=false, $error='') {
128         foreach ($path as $index) {
129             if (!isset($xml[$index])) {
130                 if (!empty($error)) {
131                     $this->error($error);
132                     return false;
133                 } else {
134                     return $default;
135                 }
136             }
138             $xml = $xml[$index];
139         }
141         if ($istext) {
142             if (!is_string($xml)) {
143                 $this->error(get_string('invalidxml', 'qformat_xml'));
144             }
145             $xml = trim($xml);
146         }
148         return $xml;
149     }
151     public function import_text_with_files($data, $path, $defaultvalue = '', $defaultformat = 'html') {
152         $field  = array();
153         $field['text'] = $this->getpath($data,
154                 array_merge($path, array('#', 'text', 0, '#')), $defaultvalue, true);
155         $field['format'] = $this->trans_format($this->getpath($data,
156                 array_merge($path, array('@', 'format')), $defaultformat));
157         $itemid = $this->import_files_as_draft($this->getpath($data,
158                 array_merge($path, array('#', 'file')), array(), false));
159         if (!empty($itemid)) {
160             $field['itemid'] = $itemid;
161         }
162         return $field;
163     }
165     public function import_files_as_draft($xml) {
166         global $USER;
167         if (empty($xml)) {
168             return null;
169         }
170         $fs = get_file_storage();
171         $itemid = file_get_unused_draft_itemid();
172         $filepaths = array();
173         foreach ($xml as $file) {
174             $filename = $this->getpath($file, array('@', 'name'), '', true);
175             $filepath = $this->getpath($file, array('@', 'path'), '/', true);
176             $fullpath = $filepath . $filename;
177             if (in_array($fullpath, $filepaths)) {
178                 debugging('Duplicate file in XML: ' . $fullpath, DEBUG_DEVELOPER);
179                 continue;
180             }
181             $filerecord = array(
182                 'contextid' => context_user::instance($USER->id)->id,
183                 'component' => 'user',
184                 'filearea'  => 'draft',
185                 'itemid'    => $itemid,
186                 'filepath'  => $filepath,
187                 'filename'  => $filename,
188             );
189             $fs->create_file_from_string($filerecord, base64_decode($file['#']));
190             $filepaths[] = $fullpath;
191         }
192         return $itemid;
193     }
195     /**
196      * import parts of question common to all types
197      * @param $question array question question array from xml tree
198      * @return object question object
199      */
200     public function import_headers($question) {
201         global $USER;
203         // This routine initialises the question object.
204         $qo = $this->defaultquestion();
206         // Question name.
207         $qo->name = $this->clean_question_name($this->getpath($question,
208                 array('#', 'name', 0, '#', 'text', 0, '#'), '', true,
209                 get_string('xmlimportnoname', 'qformat_xml')));
210         $questiontext = $this->import_text_with_files($question,
211                 array('#', 'questiontext', 0));
212         $qo->questiontext = $questiontext['text'];
213         $qo->questiontextformat = $questiontext['format'];
214         if (!empty($questiontext['itemid'])) {
215             $qo->questiontextitemid = $questiontext['itemid'];
216         }
217         // Backwards compatibility, deal with the old image tag.
218         $filedata = $this->getpath($question, array('#', 'image_base64', '0', '#'), null, false);
219         $filename = $this->getpath($question, array('#', 'image', '0', '#'), null, false);
220         if ($filedata && $filename) {
221             $fs = get_file_storage();
222             if (empty($qo->questiontextitemid)) {
223                 $qo->questiontextitemid = file_get_unused_draft_itemid();
224             }
225             $filename = clean_param(str_replace('/', '_', $filename), PARAM_FILE);
226             $filerecord = array(
227                 'contextid' => context_user::instance($USER->id)->id,
228                 'component' => 'user',
229                 'filearea'  => 'draft',
230                 'itemid'    => $qo->questiontextitemid,
231                 'filepath'  => '/',
232                 'filename'  => $filename,
233             );
234             $fs->create_file_from_string($filerecord, base64_decode($filedata));
235             $qo->questiontext .= ' <img src="@@PLUGINFILE@@/' . $filename . '" />';
236         }
238         // Restore files in generalfeedback.
239         $generalfeedback = $this->import_text_with_files($question,
240                 array('#', 'generalfeedback', 0), $qo->generalfeedback, $this->get_format($qo->questiontextformat));
241         $qo->generalfeedback = $generalfeedback['text'];
242         $qo->generalfeedbackformat = $generalfeedback['format'];
243         if (!empty($generalfeedback['itemid'])) {
244             $qo->generalfeedbackitemid = $generalfeedback['itemid'];
245         }
247         $qo->defaultmark = $this->getpath($question,
248                 array('#', 'defaultgrade', 0, '#'), $qo->defaultmark);
249         $qo->penalty = $this->getpath($question,
250                 array('#', 'penalty', 0, '#'), $qo->penalty);
252         // Fix problematic rounding from old files.
253         if (abs($qo->penalty - 0.3333333) < 0.005) {
254             $qo->penalty = 0.3333333;
255         }
257         // Read the question tags.
258         $this->import_question_tags($qo, $question);
260         return $qo;
261     }
263     /**
264      * Import the common parts of a single answer
265      * @param array answer xml tree for single answer
266      * @param bool $withanswerfiles if true, the answers are HTML (or $defaultformat)
267      *      and so may contain files, otherwise the answers are plain text.
268      * @param array Default text format for the feedback, and the answers if $withanswerfiles
269      *      is true.
270      * @return object answer object
271      */
272     public function import_answer($answer, $withanswerfiles = false, $defaultformat = 'html') {
273         $ans = new stdClass();
275         if ($withanswerfiles) {
276             $ans->answer = $this->import_text_with_files($answer, array(), '', $defaultformat);
277         } else {
278             $ans->answer = array();
279             $ans->answer['text']   = $this->getpath($answer, array('#', 'text', 0, '#'), '', true);
280             $ans->answer['format'] = FORMAT_PLAIN;
281         }
283         $ans->feedback = $this->import_text_with_files($answer, array('#', 'feedback', 0), '', $defaultformat);
285         $ans->fraction = $this->getpath($answer, array('@', 'fraction'), 0) / 100;
287         return $ans;
288     }
290     /**
291      * Import the common overall feedback fields.
292      * @param object $question the part of the XML relating to this question.
293      * @param object $qo the question data to add the fields to.
294      * @param bool $withshownumpartscorrect include the shownumcorrect field.
295      */
296     public function import_combined_feedback($qo, $questionxml, $withshownumpartscorrect = false) {
297         $fields = array('correctfeedback', 'partiallycorrectfeedback', 'incorrectfeedback');
298         foreach ($fields as $field) {
299             $qo->$field = $this->import_text_with_files($questionxml,
300                     array('#', $field, 0), '', $this->get_format($qo->questiontextformat));
301         }
303         if ($withshownumpartscorrect) {
304             $qo->shownumcorrect = array_key_exists('shownumcorrect', $questionxml['#']);
306             // Backwards compatibility.
307             if (array_key_exists('correctresponsesfeedback', $questionxml['#'])) {
308                 $qo->shownumcorrect = $this->trans_single($this->getpath($questionxml,
309                         array('#', 'correctresponsesfeedback', 0, '#'), 1));
310             }
311         }
312     }
314     /**
315      * Import a question hint
316      * @param array $hintxml hint xml fragment.
317      * @param string $defaultformat the text format to assume for hints that do not specify.
318      * @return object hint for storing in the database.
319      */
320     public function import_hint($hintxml, $defaultformat) {
321         $hint = new stdClass();
322         if (array_key_exists('hintcontent', $hintxml['#'])) {
323             // Backwards compatibility.
325             $hint->hint = $this->import_text_with_files($hintxml,
326                     array('#', 'hintcontent', 0), '', $defaultformat);
328             $hint->shownumcorrect = $this->getpath($hintxml,
329                     array('#', 'statenumberofcorrectresponses', 0, '#'), 0);
330             $hint->clearwrong = $this->getpath($hintxml,
331                     array('#', 'clearincorrectresponses', 0, '#'), 0);
332             $hint->options = $this->getpath($hintxml,
333                     array('#', 'showfeedbacktoresponses', 0, '#'), 0);
335             return $hint;
336         }
337         $hint->hint = $this->import_text_with_files($hintxml, array(), '', $defaultformat);
338         $hint->shownumcorrect = array_key_exists('shownumcorrect', $hintxml['#']);
339         $hint->clearwrong = array_key_exists('clearwrong', $hintxml['#']);
340         $hint->options = $this->getpath($hintxml, array('#', 'options', 0, '#'), '', true);
342         return $hint;
343     }
345     /**
346      * Import all the question hints
347      *
348      * @param object $qo the question data that is being constructed.
349      * @param array $questionxml The xml representing the question.
350      * @param bool $withparts whether the extra fields relating to parts should be imported.
351      * @param bool $withoptions whether the extra options field should be imported.
352      * @param string $defaultformat the text format to assume for hints that do not specify.
353      * @return array of objects representing the hints in the file.
354      */
355     public function import_hints($qo, $questionxml, $withparts = false,
356             $withoptions = false, $defaultformat = 'html') {
357         if (!isset($questionxml['#']['hint'])) {
358             return;
359         }
361         foreach ($questionxml['#']['hint'] as $hintxml) {
362             $hint = $this->import_hint($hintxml, $defaultformat);
363             $qo->hint[] = $hint->hint;
365             if ($withparts) {
366                 $qo->hintshownumcorrect[] = $hint->shownumcorrect;
367                 $qo->hintclearwrong[] = $hint->clearwrong;
368             }
370             if ($withoptions) {
371                 $qo->hintoptions[] = $hint->options;
372             }
373         }
374     }
376     /**
377      * Import all the question tags
378      *
379      * @param object $qo the question data that is being constructed.
380      * @param array $questionxml The xml representing the question.
381      * @return array of objects representing the tags in the file.
382      */
383     public function import_question_tags($qo, $questionxml) {
384         global $CFG;
386         if (core_tag_tag::is_enabled('core_question', 'question')
387                 && array_key_exists('tags', $questionxml['#'])
388                 && !empty($questionxml['#']['tags'][0]['#']['tag'])) {
389             $qo->tags = array();
390             foreach ($questionxml['#']['tags'][0]['#']['tag'] as $tagdata) {
391                 $qo->tags[] = $this->getpath($tagdata, array('#', 'text', 0, '#'), '', true);
392             }
393         }
394     }
396     /**
397      * Import files from a node in the XML.
398      * @param array $xml an array of <file> nodes from the the parsed XML.
399      * @return array of things representing files - in the form that save_question expects.
400      */
401     public function import_files($xml) {
402         $files = array();
403         foreach ($xml as $file) {
404             $data = new stdClass();
405             $data->content = $file['#'];
406             $data->encoding = $file['@']['encoding'];
407             $data->name = $file['@']['name'];
408             $files[] = $data;
409         }
410         return $files;
411     }
413     /**
414      * import multiple choice question
415      * @param array question question array from xml tree
416      * @return object question object
417      */
418     public function import_multichoice($question) {
419         // Get common parts.
420         $qo = $this->import_headers($question);
422         // Header parts particular to multichoice.
423         $qo->qtype = 'multichoice';
424         $single = $this->getpath($question, array('#', 'single', 0, '#'), 'true');
425         $qo->single = $this->trans_single($single);
426         $shuffleanswers = $this->getpath($question,
427                 array('#', 'shuffleanswers', 0, '#'), 'false');
428         $qo->answernumbering = $this->getpath($question,
429                 array('#', 'answernumbering', 0, '#'), 'abc');
430         $qo->shuffleanswers = $this->trans_single($shuffleanswers);
432         // There was a time on the 1.8 branch when it could output an empty
433         // answernumbering tag, so fix up any found.
434         if (empty($qo->answernumbering)) {
435             $qo->answernumbering = 'abc';
436         }
438         // Run through the answers.
439         $answers = $question['#']['answer'];
440         $acount = 0;
441         foreach ($answers as $answer) {
442             $ans = $this->import_answer($answer, true, $this->get_format($qo->questiontextformat));
443             $qo->answer[$acount] = $ans->answer;
444             $qo->fraction[$acount] = $ans->fraction;
445             $qo->feedback[$acount] = $ans->feedback;
446             ++$acount;
447         }
449         $this->import_combined_feedback($qo, $question, true);
450         $this->import_hints($qo, $question, true, false, $this->get_format($qo->questiontextformat));
452         return $qo;
453     }
455     /**
456      * Import cloze type question
457      * @param array question question array from xml tree
458      * @return object question object
459      */
460     public function import_multianswer($question) {
461         global $USER;
462         question_bank::get_qtype('multianswer');
464         $questiontext = $this->import_text_with_files($question,
465                 array('#', 'questiontext', 0));
466         $qo = qtype_multianswer_extract_question($questiontext);
468         // Header parts particular to multianswer.
469         $qo->qtype = 'multianswer';
471         // Only set the course if the data is available.
472         if (isset($this->course)) {
473             $qo->course = $this->course;
474         }
476         $qo->name = $this->clean_question_name($this->import_text($question['#']['name'][0]['#']['text']));
477         $qo->questiontextformat = $questiontext['format'];
478         $qo->questiontext = $qo->questiontext['text'];
479         if (!empty($questiontext['itemid'])) {
480             $qo->questiontextitemid = $questiontext['itemid'];
481         }
483         // Backwards compatibility, deal with the old image tag.
484         $filedata = $this->getpath($question, array('#', 'image_base64', '0', '#'), null, false);
485         $filename = $this->getpath($question, array('#', 'image', '0', '#'), null, false);
486         if ($filedata && $filename) {
487             $fs = get_file_storage();
488             if (empty($qo->questiontextitemid)) {
489                 $qo->questiontextitemid = file_get_unused_draft_itemid();
490             }
491             $filename = clean_param(str_replace('/', '_', $filename), PARAM_FILE);
492             $filerecord = array(
493                 'contextid' => context_user::instance($USER->id)->id,
494                 'component' => 'user',
495                 'filearea'  => 'draft',
496                 'itemid'    => $qo->questiontextitemid,
497                 'filepath'  => '/',
498                 'filename'  => $filename,
499             );
500             $fs->create_file_from_string($filerecord, base64_decode($filedata));
501             $qo->questiontext .= ' <img src="@@PLUGINFILE@@/' . $filename . '" />';
502         }
504         // Restore files in generalfeedback.
505         $generalfeedback = $this->import_text_with_files($question,
506                 array('#', 'generalfeedback', 0), $qo->generalfeedback, $this->get_format($qo->questiontextformat));
507         $qo->generalfeedback = $generalfeedback['text'];
508         $qo->generalfeedbackformat = $generalfeedback['format'];
509         if (!empty($generalfeedback['itemid'])) {
510             $qo->generalfeedbackitemid = $generalfeedback['itemid'];
511         }
513         $qo->penalty = $this->getpath($question,
514                 array('#', 'penalty', 0, '#'), $this->defaultquestion()->penalty);
515         // Fix problematic rounding from old files.
516         if (abs($qo->penalty - 0.3333333) < 0.005) {
517             $qo->penalty = 0.3333333;
518         }
520         $this->import_hints($qo, $question, true, false, $this->get_format($qo->questiontextformat));
521         $this->import_question_tags($qo, $question);
523         return $qo;
524     }
526     /**
527      * Import true/false type question
528      * @param array question question array from xml tree
529      * @return object question object
530      */
531     public function import_truefalse($question) {
532         // Get common parts.
533         global $OUTPUT;
534         $qo = $this->import_headers($question);
536         // Header parts particular to true/false.
537         $qo->qtype = 'truefalse';
539         // In the past, it used to be assumed that the two answers were in the file
540         // true first, then false. Howevever that was not always true. Now, we
541         // try to match on the answer text, but in old exports, this will be a localised
542         // string, so if we don't find true or false, we fall back to the old system.
543         $first = true;
544         $warning = false;
545         foreach ($question['#']['answer'] as $answer) {
546             $answertext = $this->getpath($answer,
547                     array('#', 'text', 0, '#'), '', true);
548             $feedback = $this->import_text_with_files($answer,
549                     array('#', 'feedback', 0), '', $this->get_format($qo->questiontextformat));
551             if ($answertext != 'true' && $answertext != 'false') {
552                 // Old style file, assume order is true/false.
553                 $warning = true;
554                 if ($first) {
555                     $answertext = 'true';
556                 } else {
557                     $answertext = 'false';
558                 }
559             }
561             if ($answertext == 'true') {
562                 $qo->answer = ($answer['@']['fraction'] == 100);
563                 $qo->correctanswer = $qo->answer;
564                 $qo->feedbacktrue = $feedback;
565             } else {
566                 $qo->answer = ($answer['@']['fraction'] != 100);
567                 $qo->correctanswer = $qo->answer;
568                 $qo->feedbackfalse = $feedback;
569             }
570             $first = false;
571         }
573         if ($warning) {
574             $a = new stdClass();
575             $a->questiontext = $qo->questiontext;
576             $a->answer = get_string($qo->correctanswer ? 'true' : 'false', 'qtype_truefalse');
577             echo $OUTPUT->notification(get_string('truefalseimporterror', 'qformat_xml', $a));
578         }
580         $this->import_hints($qo, $question, false, false, $this->get_format($qo->questiontextformat));
582         return $qo;
583     }
585     /**
586      * Import short answer type question
587      * @param array question question array from xml tree
588      * @return object question object
589      */
590     public function import_shortanswer($question) {
591         // Get common parts.
592         $qo = $this->import_headers($question);
594         // Header parts particular to shortanswer.
595         $qo->qtype = 'shortanswer';
597         // Get usecase.
598         $qo->usecase = $this->getpath($question, array('#', 'usecase', 0, '#'), $qo->usecase);
600         // Run through the answers.
601         $answers = $question['#']['answer'];
602         $acount = 0;
603         foreach ($answers as $answer) {
604             $ans = $this->import_answer($answer, false, $this->get_format($qo->questiontextformat));
605             $qo->answer[$acount] = $ans->answer['text'];
606             $qo->fraction[$acount] = $ans->fraction;
607             $qo->feedback[$acount] = $ans->feedback;
608             ++$acount;
609         }
611         $this->import_hints($qo, $question, false, false, $this->get_format($qo->questiontextformat));
613         return $qo;
614     }
616     /**
617      * Import description type question
618      * @param array question question array from xml tree
619      * @return object question object
620      */
621     public function import_description($question) {
622         // Get common parts.
623         $qo = $this->import_headers($question);
624         // Header parts particular to shortanswer.
625         $qo->qtype = 'description';
626         $qo->defaultmark = 0;
627         $qo->length = 0;
628         return $qo;
629     }
631     /**
632      * Import numerical type question
633      * @param array question question array from xml tree
634      * @return object question object
635      */
636     public function import_numerical($question) {
637         // Get common parts.
638         $qo = $this->import_headers($question);
640         // Header parts particular to numerical.
641         $qo->qtype = 'numerical';
643         // Get answers array.
644         $answers = $question['#']['answer'];
645         $qo->answer = array();
646         $qo->feedback = array();
647         $qo->fraction = array();
648         $qo->tolerance = array();
649         foreach ($answers as $answer) {
650             // Answer outside of <text> is deprecated.
651             $obj = $this->import_answer($answer, false, $this->get_format($qo->questiontextformat));
652             $qo->answer[] = $obj->answer['text'];
653             if (empty($qo->answer)) {
654                 $qo->answer = '*';
655             }
656             $qo->feedback[]  = $obj->feedback;
657             $qo->tolerance[] = $this->getpath($answer, array('#', 'tolerance', 0, '#'), 0);
659             // Fraction as a tag is deprecated.
660             $fraction = $this->getpath($answer, array('@', 'fraction'), 0) / 100;
661             $qo->fraction[] = $this->getpath($answer,
662                     array('#', 'fraction', 0, '#'), $fraction); // Deprecated.
663         }
665         // Get the units array.
666         $qo->unit = array();
667         $units = $this->getpath($question, array('#', 'units', 0, '#', 'unit'), array());
668         if (!empty($units)) {
669             $qo->multiplier = array();
670             foreach ($units as $unit) {
671                 $qo->multiplier[] = $this->getpath($unit, array('#', 'multiplier', 0, '#'), 1);
672                 $qo->unit[] = $this->getpath($unit, array('#', 'unit_name', 0, '#'), '', true);
673             }
674         }
675         $qo->unitgradingtype = $this->getpath($question, array('#', 'unitgradingtype', 0, '#'), 0);
676         $qo->unitpenalty = $this->getpath($question, array('#', 'unitpenalty', 0, '#'), 0.1);
677         $qo->showunits = $this->getpath($question, array('#', 'showunits', 0, '#'), null);
678         $qo->unitsleft = $this->getpath($question, array('#', 'unitsleft', 0, '#'), 0);
679         $qo->instructions['text'] = '';
680         $qo->instructions['format'] = FORMAT_HTML;
681         $instructions = $this->getpath($question, array('#', 'instructions'), array());
682         if (!empty($instructions)) {
683             $qo->instructions = $this->import_text_with_files($instructions,
684                     array('0'), '', $this->get_format($qo->questiontextformat));
685         }
687         if (is_null($qo->showunits)) {
688             // Set a good default, depending on whether there are any units defined.
689             if (empty($qo->unit)) {
690                 $qo->showunits = 3; // This is qtype_numerical::UNITNONE, but we cannot refer to that constant here.
691             } else {
692                 $qo->showunits = 0; // This is qtype_numerical::UNITOPTIONAL, but we cannot refer to that constant here.
693             }
694         }
696         $this->import_hints($qo, $question, false, false, $this->get_format($qo->questiontextformat));
698         return $qo;
699     }
701     /**
702      * Import matching type question
703      * @param array question question array from xml tree
704      * @return object question object
705      */
706     public function import_match($question) {
707         // Get common parts.
708         $qo = $this->import_headers($question);
710         // Header parts particular to matching.
711         $qo->qtype = 'match';
712         $qo->shuffleanswers = $this->trans_single($this->getpath($question,
713                 array('#', 'shuffleanswers', 0, '#'), 1));
715         // Run through subquestions.
716         $qo->subquestions = array();
717         $qo->subanswers = array();
718         foreach ($question['#']['subquestion'] as $subqxml) {
719             $qo->subquestions[] = $this->import_text_with_files($subqxml,
720                     array(), '', $this->get_format($qo->questiontextformat));
722             $answers = $this->getpath($subqxml, array('#', 'answer'), array());
723             $qo->subanswers[] = $this->getpath($subqxml,
724                     array('#', 'answer', 0, '#', 'text', 0, '#'), '', true);
725         }
727         $this->import_combined_feedback($qo, $question, true);
728         $this->import_hints($qo, $question, true, false, $this->get_format($qo->questiontextformat));
730         return $qo;
731     }
733     /**
734      * Import essay type question
735      * @param array question question array from xml tree
736      * @return object question object
737      */
738     public function import_essay($question) {
739         // Get common parts.
740         $qo = $this->import_headers($question);
742         // Header parts particular to essay.
743         $qo->qtype = 'essay';
745         $qo->responseformat = $this->getpath($question,
746                 array('#', 'responseformat', 0, '#'), 'editor');
747         $qo->responsefieldlines = $this->getpath($question,
748                 array('#', 'responsefieldlines', 0, '#'), 15);
749         $qo->responserequired = $this->getpath($question,
750                 array('#', 'responserequired', 0, '#'), 1);
751         $qo->attachments = $this->getpath($question,
752                 array('#', 'attachments', 0, '#'), 0);
753         $qo->attachmentsrequired = $this->getpath($question,
754                 array('#', 'attachmentsrequired', 0, '#'), 0);
755         $qo->graderinfo = $this->import_text_with_files($question,
756                 array('#', 'graderinfo', 0), '', $this->get_format($qo->questiontextformat));
757         $qo->responsetemplate['text'] = $this->getpath($question,
758                 array('#', 'responsetemplate', 0, '#', 'text', 0, '#'), '', true);
759         $qo->responsetemplate['format'] = $this->trans_format($this->getpath($question,
760                 array('#', 'responsetemplate', 0, '@', 'format'), $this->get_format($qo->questiontextformat)));
762         return $qo;
763     }
765     /**
766      * Import a calculated question
767      * @param object $question the imported XML data.
768      */
769     public function import_calculated($question) {
771         // Get common parts.
772         $qo = $this->import_headers($question);
774         // Header parts particular to calculated.
775         $qo->qtype = 'calculated';
776         $qo->synchronize = $this->getpath($question, array('#', 'synchronize', 0, '#'), 0);
777         $single = $this->getpath($question, array('#', 'single', 0, '#'), 'true');
778         $qo->single = $this->trans_single($single);
779         $shuffleanswers = $this->getpath($question, array('#', 'shuffleanswers', 0, '#'), 'false');
780         $qo->answernumbering = $this->getpath($question,
781                 array('#', 'answernumbering', 0, '#'), 'abc');
782         $qo->shuffleanswers = $this->trans_single($shuffleanswers);
784         $this->import_combined_feedback($qo, $question);
786         $qo->unitgradingtype = $this->getpath($question,
787                 array('#', 'unitgradingtype', 0, '#'), 0);
788         $qo->unitpenalty = $this->getpath($question, array('#', 'unitpenalty', 0, '#'), null);
789         $qo->showunits = $this->getpath($question, array('#', 'showunits', 0, '#'), 0);
790         $qo->unitsleft = $this->getpath($question, array('#', 'unitsleft', 0, '#'), 0);
791         $qo->instructions = $this->getpath($question,
792                 array('#', 'instructions', 0, '#', 'text', 0, '#'), '', true);
793         if (!empty($instructions)) {
794             $qo->instructions = $this->import_text_with_files($instructions,
795                     array('0'), '', $this->get_format($qo->questiontextformat));
796         }
798         // Get answers array.
799         $answers = $question['#']['answer'];
800         $qo->answer = array();
801         $qo->feedback = array();
802         $qo->fraction = array();
803         $qo->tolerance = array();
804         $qo->tolerancetype = array();
805         $qo->correctanswerformat = array();
806         $qo->correctanswerlength = array();
807         $qo->feedback = array();
808         foreach ($answers as $answer) {
809             $ans = $this->import_answer($answer, true, $this->get_format($qo->questiontextformat));
810             // Answer outside of <text> is deprecated.
811             if (empty($ans->answer['text'])) {
812                 $ans->answer['text'] = '*';
813             }
814             $qo->answer[] = $ans->answer['text'];
815             $qo->feedback[] = $ans->feedback;
816             $qo->tolerance[] = $answer['#']['tolerance'][0]['#'];
817             // Fraction as a tag is deprecated.
818             if (!empty($answer['#']['fraction'][0]['#'])) {
819                 $qo->fraction[] = $answer['#']['fraction'][0]['#'];
820             } else {
821                 $qo->fraction[] = $answer['@']['fraction'] / 100;
822             }
823             $qo->tolerancetype[] = $answer['#']['tolerancetype'][0]['#'];
824             $qo->correctanswerformat[] = $answer['#']['correctanswerformat'][0]['#'];
825             $qo->correctanswerlength[] = $answer['#']['correctanswerlength'][0]['#'];
826         }
827         // Get units array.
828         $qo->unit = array();
829         if (isset($question['#']['units'][0]['#']['unit'])) {
830             $units = $question['#']['units'][0]['#']['unit'];
831             $qo->multiplier = array();
832             foreach ($units as $unit) {
833                 $qo->multiplier[] = $unit['#']['multiplier'][0]['#'];
834                 $qo->unit[] = $unit['#']['unit_name'][0]['#'];
835             }
836         }
837         $instructions = $this->getpath($question, array('#', 'instructions'), array());
838         if (!empty($instructions)) {
839             $qo->instructions = $this->import_text_with_files($instructions,
840                     array('0'), '', $this->get_format($qo->questiontextformat));
841         }
843         if (is_null($qo->unitpenalty)) {
844             // Set a good default, depending on whether there are any units defined.
845             if (empty($qo->unit)) {
846                 $qo->showunits = 3; // This is qtype_numerical::UNITNONE, but we cannot refer to that constant here.
847             } else {
848                 $qo->showunits = 0; // This is qtype_numerical::UNITOPTIONAL, but we cannot refer to that constant here.
849             }
850         }
852         $datasets = $question['#']['dataset_definitions'][0]['#']['dataset_definition'];
853         $qo->dataset = array();
854         $qo->datasetindex= 0;
855         foreach ($datasets as $dataset) {
856             $qo->datasetindex++;
857             $qo->dataset[$qo->datasetindex] = new stdClass();
858             $qo->dataset[$qo->datasetindex]->status =
859                     $this->import_text($dataset['#']['status'][0]['#']['text']);
860             $qo->dataset[$qo->datasetindex]->name =
861                     $this->import_text($dataset['#']['name'][0]['#']['text']);
862             $qo->dataset[$qo->datasetindex]->type =
863                     $dataset['#']['type'][0]['#'];
864             $qo->dataset[$qo->datasetindex]->distribution =
865                     $this->import_text($dataset['#']['distribution'][0]['#']['text']);
866             $qo->dataset[$qo->datasetindex]->max =
867                     $this->import_text($dataset['#']['maximum'][0]['#']['text']);
868             $qo->dataset[$qo->datasetindex]->min =
869                     $this->import_text($dataset['#']['minimum'][0]['#']['text']);
870             $qo->dataset[$qo->datasetindex]->length =
871                     $this->import_text($dataset['#']['decimals'][0]['#']['text']);
872             $qo->dataset[$qo->datasetindex]->distribution =
873                     $this->import_text($dataset['#']['distribution'][0]['#']['text']);
874             $qo->dataset[$qo->datasetindex]->itemcount = $dataset['#']['itemcount'][0]['#'];
875             $qo->dataset[$qo->datasetindex]->datasetitem = array();
876             $qo->dataset[$qo->datasetindex]->itemindex = 0;
877             $qo->dataset[$qo->datasetindex]->number_of_items = $this->getpath($dataset,
878                     array('#', 'number_of_items', 0, '#'), 0);
879             $datasetitems = $this->getpath($dataset,
880                     array('#', 'dataset_items', 0, '#', 'dataset_item'), array());
881             foreach ($datasetitems as $datasetitem) {
882                 $qo->dataset[$qo->datasetindex]->itemindex++;
883                 $qo->dataset[$qo->datasetindex]->datasetitem[
884                         $qo->dataset[$qo->datasetindex]->itemindex] = new stdClass();
885                 $qo->dataset[$qo->datasetindex]->datasetitem[
886                         $qo->dataset[$qo->datasetindex]->itemindex]->itemnumber =
887                                 $datasetitem['#']['number'][0]['#'];
888                 $qo->dataset[$qo->datasetindex]->datasetitem[
889                         $qo->dataset[$qo->datasetindex]->itemindex]->value =
890                                 $datasetitem['#']['value'][0]['#'];
891             }
892         }
894         $this->import_hints($qo, $question, false, false, $this->get_format($qo->questiontextformat));
896         return $qo;
897     }
899     /**
900      * This is not a real question type. It's a dummy type used to specify the
901      * import category. The format is:
902      * <question type="category">
903      *     <category>tom/dick/harry</category>
904      * </question>
905      */
906     protected function import_category($question) {
907         $qo = new stdClass();
908         $qo->qtype = 'category';
909         $qo->category = $this->import_text($question['#']['category'][0]['#']['text']);
910         return $qo;
911     }
913     /**
914      * Parse the array of lines into an array of questions
915      * this *could* burn memory - but it won't happen that much
916      * so fingers crossed!
917      * @param array of lines from the input file.
918      * @param stdClass $context
919      * @return array (of objects) question objects.
920      */
921     protected function readquestions($lines) {
922         // We just need it as one big string.
923         $lines = implode('', $lines);
925         // This converts xml to big nasty data structure
926         // the 0 means keep white space as it is (important for markdown format).
927         try {
928             $xml = xmlize($lines, 0, 'UTF-8', true);
929         } catch (xml_format_exception $e) {
930             $this->error($e->getMessage(), '');
931             return false;
932         }
933         unset($lines); // No need to keep this in memory.
934         return $this->import_questions($xml['quiz']['#']['question']);
935     }
937     /**
938      * @param array $xml the xmlized xml
939      * @return stdClass[] question objects to pass to question type save_question_options
940      */
941     public function import_questions($xml) {
942         $questions = array();
944         // Iterate through questions.
945         foreach ($xml as $questionxml) {
946             $qo = $this->import_question($questionxml);
948             // Stick the result in the $questions array.
949             if ($qo) {
950                 $questions[] = $qo;
951             }
952         }
953         return $questions;
954     }
956     /**
957      * @param array $questionxml xml describing the question
958      * @return null|stdClass an object with data to be fed to question type save_question_options
959      */
960     protected function import_question($questionxml) {
961         $questiontype = $questionxml['@']['type'];
963         if ($questiontype == 'multichoice') {
964             return $this->import_multichoice($questionxml);
965         } else if ($questiontype == 'truefalse') {
966             return $this->import_truefalse($questionxml);
967         } else if ($questiontype == 'shortanswer') {
968             return $this->import_shortanswer($questionxml);
969         } else if ($questiontype == 'numerical') {
970             return $this->import_numerical($questionxml);
971         } else if ($questiontype == 'description') {
972             return $this->import_description($questionxml);
973         } else if ($questiontype == 'matching' || $questiontype == 'match') {
974             return $this->import_match($questionxml);
975         } else if ($questiontype == 'cloze' || $questiontype == 'multianswer') {
976             return $this->import_multianswer($questionxml);
977         } else if ($questiontype == 'essay') {
978             return $this->import_essay($questionxml);
979         } else if ($questiontype == 'calculated') {
980             return $this->import_calculated($questionxml);
981         } else if ($questiontype == 'calculatedsimple') {
982             $qo = $this->import_calculated($questionxml);
983             $qo->qtype = 'calculatedsimple';
984             return $qo;
985         } else if ($questiontype == 'calculatedmulti') {
986             $qo = $this->import_calculated($questionxml);
987             $qo->qtype = 'calculatedmulti';
988             return $qo;
989         } else if ($questiontype == 'category') {
990             return $this->import_category($questionxml);
992         } else {
993             // Not a type we handle ourselves. See if the question type wants
994             // to handle it.
995             if (!$qo = $this->try_importing_using_qtypes($questionxml, null, null, $questiontype)) {
996                 $this->error(get_string('xmltypeunsupported', 'qformat_xml', $questiontype));
997                 return null;
998             }
999             return $qo;
1000         }
1001     }
1003     // EXPORT FUNCTIONS START HERE.
1005     public function export_file_extension() {
1006         return '.xml';
1007     }
1009     /**
1010      * Turn the internal question type name into a human readable form.
1011      * (In the past, the code used to use integers internally. Now, it uses
1012      * strings, so there is less need for this, but to maintain
1013      * backwards-compatibility we change two of the type names.)
1014      * @param string $qtype question type plugin name.
1015      * @return string $qtype string to use in the file.
1016      */
1017     protected function get_qtype($qtype) {
1018         switch($qtype) {
1019             case 'match':
1020                 return 'matching';
1021             case 'multianswer':
1022                 return 'cloze';
1023             default:
1024                 return $qtype;
1025         }
1026     }
1028     /**
1029      * Convert internal Moodle text format code into
1030      * human readable form
1031      * @param int id internal code
1032      * @return string format text
1033      */
1034     public function get_format($id) {
1035         switch($id) {
1036             case FORMAT_MOODLE:
1037                 return 'moodle_auto_format';
1038             case FORMAT_HTML:
1039                 return 'html';
1040             case FORMAT_PLAIN:
1041                 return 'plain_text';
1042             case FORMAT_WIKI:
1043                 return 'wiki_like';
1044             case FORMAT_MARKDOWN:
1045                 return 'markdown';
1046             default:
1047                 return 'unknown';
1048         }
1049     }
1051     /**
1052      * Convert internal single question code into
1053      * human readable form
1054      * @param int id single question code
1055      * @return string single question string
1056      */
1057     public function get_single($id) {
1058         switch($id) {
1059             case 0:
1060                 return 'false';
1061             case 1:
1062                 return 'true';
1063             default:
1064                 return 'unknown';
1065         }
1066     }
1068     /**
1069      * Take a string, and wrap it in a CDATA secion, if that is required to make
1070      * the output XML valid.
1071      * @param string $string a string
1072      * @return string the string, wrapped in CDATA if necessary.
1073      */
1074     public function xml_escape($string) {
1075         if (!empty($string) && htmlspecialchars($string) != $string) {
1076             // If the string contains something that looks like the end
1077             // of a CDATA section, then we need to avoid errors by splitting
1078             // the string between two CDATA sections.
1079             $string = str_replace(']]>', ']]]]><![CDATA[>', $string);
1080             return "<![CDATA[{$string}]]>";
1081         } else {
1082             return $string;
1083         }
1084     }
1086     /**
1087      * Generates <text></text> tags, processing raw text therein
1088      * @param string $raw the content to output.
1089      * @param int $indent the current indent level.
1090      * @param bool $short stick it on one line.
1091      * @return string formatted text.
1092      */
1093     public function writetext($raw, $indent = 0, $short = true) {
1094         $indent = str_repeat('  ', $indent);
1095         $raw = $this->xml_escape($raw);
1097         if ($short) {
1098             $xml = "{$indent}<text>{$raw}</text>\n";
1099         } else {
1100             $xml = "{$indent}<text>\n{$raw}\n{$indent}</text>\n";
1101         }
1103         return $xml;
1104     }
1106     /**
1107      * Generte the XML to represent some files.
1108      * @param array of store array of stored_file objects.
1109      * @return string $string the XML.
1110      */
1111     public function write_files($files) {
1112         if (empty($files)) {
1113             return '';
1114         }
1115         $string = '';
1116         foreach ($files as $file) {
1117             if ($file->is_directory()) {
1118                 continue;
1119             }
1120             $string .= '<file name="' . $file->get_filename() . '" path="' . $file->get_filepath() . '" encoding="base64">';
1121             $string .= base64_encode($file->get_content());
1122             $string .= "</file>\n";
1123         }
1124         return $string;
1125     }
1127     protected function presave_process($content) {
1128         // Override to allow us to add xml headers and footers.
1129         return '<?xml version="1.0" encoding="UTF-8"?>
1130 <quiz>
1131 ' . $content . '</quiz>';
1132     }
1134     /**
1135      * Turns question into an xml segment
1136      * @param object $question the question data.
1137      * @return string xml segment
1138      */
1139     public function writequestion($question) {
1140         global $CFG, $OUTPUT;
1142         $invalidquestion = false;
1143         $fs = get_file_storage();
1144         $contextid = $question->contextid;
1145         // Get files used by the questiontext.
1146         $question->questiontextfiles = $fs->get_area_files(
1147                 $contextid, 'question', 'questiontext', $question->id);
1148         // Get files used by the generalfeedback.
1149         $question->generalfeedbackfiles = $fs->get_area_files(
1150                 $contextid, 'question', 'generalfeedback', $question->id);
1151         if (!empty($question->options->answers)) {
1152             foreach ($question->options->answers as $answer) {
1153                 $answer->answerfiles = $fs->get_area_files(
1154                         $contextid, 'question', 'answer', $answer->id);
1155                 $answer->feedbackfiles = $fs->get_area_files(
1156                         $contextid, 'question', 'answerfeedback', $answer->id);
1157             }
1158         }
1160         $expout = '';
1162         // Add a comment linking this to the original question id.
1163         $expout .= "<!-- question: {$question->id}  -->\n";
1165         // Check question type.
1166         $questiontype = $this->get_qtype($question->qtype);
1168         // Categories are a special case.
1169         if ($question->qtype == 'category') {
1170             $categorypath = $this->writetext($question->category);
1171             $expout .= "  <question type=\"category\">\n";
1172             $expout .= "    <category>\n";
1173             $expout .= "        {$categorypath}\n";
1174             $expout .= "    </category>\n";
1175             $expout .= "  </question>\n";
1176             return $expout;
1177         }
1179         // Now we know we are are handing a real question.
1180         // Output the generic information.
1181         $expout .= "  <question type=\"{$questiontype}\">\n";
1182         $expout .= "    <name>\n";
1183         $expout .= $this->writetext($question->name, 3);
1184         $expout .= "    </name>\n";
1185         $expout .= "    <questiontext {$this->format($question->questiontextformat)}>\n";
1186         $expout .= $this->writetext($question->questiontext, 3);
1187         $expout .= $this->write_files($question->questiontextfiles);
1188         $expout .= "    </questiontext>\n";
1189         $expout .= "    <generalfeedback {$this->format($question->generalfeedbackformat)}>\n";
1190         $expout .= $this->writetext($question->generalfeedback, 3);
1191         $expout .= $this->write_files($question->generalfeedbackfiles);
1192         $expout .= "    </generalfeedback>\n";
1193         if ($question->qtype != 'multianswer') {
1194             $expout .= "    <defaultgrade>{$question->defaultmark}</defaultgrade>\n";
1195         }
1196         $expout .= "    <penalty>{$question->penalty}</penalty>\n";
1197         $expout .= "    <hidden>{$question->hidden}</hidden>\n";
1199         // The rest of the output depends on question type.
1200         switch($question->qtype) {
1201             case 'category':
1202                 // Not a qtype really - dummy used for category switching.
1203                 break;
1205             case 'truefalse':
1206                 $trueanswer = $question->options->answers[$question->options->trueanswer];
1207                 $trueanswer->answer = 'true';
1208                 $expout .= $this->write_answer($trueanswer);
1210                 $falseanswer = $question->options->answers[$question->options->falseanswer];
1211                 $falseanswer->answer = 'false';
1212                 $expout .= $this->write_answer($falseanswer);
1213                 break;
1215             case 'multichoice':
1216                 $expout .= "    <single>" . $this->get_single($question->options->single) .
1217                         "</single>\n";
1218                 $expout .= "    <shuffleanswers>" .
1219                         $this->get_single($question->options->shuffleanswers) .
1220                         "</shuffleanswers>\n";
1221                 $expout .= "    <answernumbering>" . $question->options->answernumbering .
1222                         "</answernumbering>\n";
1223                 $expout .= $this->write_combined_feedback($question->options, $question->id, $question->contextid);
1224                 $expout .= $this->write_answers($question->options->answers);
1225                 break;
1227             case 'shortanswer':
1228                 $expout .= "    <usecase>{$question->options->usecase}</usecase>\n";
1229                 $expout .= $this->write_answers($question->options->answers);
1230                 break;
1232             case 'numerical':
1233                 foreach ($question->options->answers as $answer) {
1234                     $expout .= $this->write_answer($answer,
1235                             "      <tolerance>{$answer->tolerance}</tolerance>\n");
1236                 }
1238                 $units = $question->options->units;
1239                 if (count($units)) {
1240                     $expout .= "<units>\n";
1241                     foreach ($units as $unit) {
1242                         $expout .= "  <unit>\n";
1243                         $expout .= "    <multiplier>{$unit->multiplier}</multiplier>\n";
1244                         $expout .= "    <unit_name>{$unit->unit}</unit_name>\n";
1245                         $expout .= "  </unit>\n";
1246                     }
1247                     $expout .= "</units>\n";
1248                 }
1249                 if (isset($question->options->unitgradingtype)) {
1250                     $expout .= "    <unitgradingtype>" . $question->options->unitgradingtype .
1251                             "</unitgradingtype>\n";
1252                 }
1253                 if (isset($question->options->unitpenalty)) {
1254                     $expout .= "    <unitpenalty>{$question->options->unitpenalty}</unitpenalty>\n";
1255                 }
1256                 if (isset($question->options->showunits)) {
1257                     $expout .= "    <showunits>{$question->options->showunits}</showunits>\n";
1258                 }
1259                 if (isset($question->options->unitsleft)) {
1260                     $expout .= "    <unitsleft>{$question->options->unitsleft}</unitsleft>\n";
1261                 }
1262                 if (!empty($question->options->instructionsformat)) {
1263                     $files = $fs->get_area_files($contextid, 'qtype_numerical',
1264                             'instruction', $question->id);
1265                     $expout .= "    <instructions " .
1266                             $this->format($question->options->instructionsformat) . ">\n";
1267                     $expout .= $this->writetext($question->options->instructions, 3);
1268                     $expout .= $this->write_files($files);
1269                     $expout .= "    </instructions>\n";
1270                 }
1271                 break;
1273             case 'match':
1274                 $expout .= "    <shuffleanswers>" .
1275                         $this->get_single($question->options->shuffleanswers) .
1276                         "</shuffleanswers>\n";
1277                 $expout .= $this->write_combined_feedback($question->options, $question->id, $question->contextid);
1278                 foreach ($question->options->subquestions as $subquestion) {
1279                     $files = $fs->get_area_files($contextid, 'qtype_match',
1280                             'subquestion', $subquestion->id);
1281                     $expout .= "    <subquestion " .
1282                             $this->format($subquestion->questiontextformat) . ">\n";
1283                     $expout .= $this->writetext($subquestion->questiontext, 3);
1284                     $expout .= $this->write_files($files);
1285                     $expout .= "      <answer>\n";
1286                     $expout .= $this->writetext($subquestion->answertext, 4);
1287                     $expout .= "      </answer>\n";
1288                     $expout .= "    </subquestion>\n";
1289                 }
1290                 break;
1292             case 'description':
1293                 // Nothing else to do.
1294                 break;
1296             case 'multianswer':
1297                 foreach ($question->options->questions as $index => $subq) {
1298                     $expout = str_replace('{#' . $index . '}', $subq->questiontext, $expout);
1299                 }
1300                 break;
1302             case 'essay':
1303                 $expout .= "    <responseformat>" . $question->options->responseformat .
1304                         "</responseformat>\n";
1305                 $expout .= "    <responserequired>" . $question->options->responserequired .
1306                         "</responserequired>\n";
1307                 $expout .= "    <responsefieldlines>" . $question->options->responsefieldlines .
1308                         "</responsefieldlines>\n";
1309                 $expout .= "    <attachments>" . $question->options->attachments .
1310                         "</attachments>\n";
1311                 $expout .= "    <attachmentsrequired>" . $question->options->attachmentsrequired .
1312                         "</attachmentsrequired>\n";
1313                 $expout .= "    <graderinfo " .
1314                         $this->format($question->options->graderinfoformat) . ">\n";
1315                 $expout .= $this->writetext($question->options->graderinfo, 3);
1316                 $expout .= $this->write_files($fs->get_area_files($contextid, 'qtype_essay',
1317                         'graderinfo', $question->id));
1318                 $expout .= "    </graderinfo>\n";
1319                 $expout .= "    <responsetemplate " .
1320                         $this->format($question->options->responsetemplateformat) . ">\n";
1321                 $expout .= $this->writetext($question->options->responsetemplate, 3);
1322                 $expout .= "    </responsetemplate>\n";
1323                 break;
1325             case 'calculated':
1326             case 'calculatedsimple':
1327             case 'calculatedmulti':
1328                 $expout .= "    <synchronize>{$question->options->synchronize}</synchronize>\n";
1329                 $expout .= "    <single>{$question->options->single}</single>\n";
1330                 $expout .= "    <answernumbering>" . $question->options->answernumbering .
1331                         "</answernumbering>\n";
1332                 $expout .= "    <shuffleanswers>" . $question->options->shuffleanswers .
1333                         "</shuffleanswers>\n";
1335                 $component = 'qtype_' . $question->qtype;
1336                 $files = $fs->get_area_files($contextid, $component,
1337                         'correctfeedback', $question->id);
1338                 $expout .= "    <correctfeedback>\n";
1339                 $expout .= $this->writetext($question->options->correctfeedback, 3);
1340                 $expout .= $this->write_files($files);
1341                 $expout .= "    </correctfeedback>\n";
1343                 $files = $fs->get_area_files($contextid, $component,
1344                         'partiallycorrectfeedback', $question->id);
1345                 $expout .= "    <partiallycorrectfeedback>\n";
1346                 $expout .= $this->writetext($question->options->partiallycorrectfeedback, 3);
1347                 $expout .= $this->write_files($files);
1348                 $expout .= "    </partiallycorrectfeedback>\n";
1350                 $files = $fs->get_area_files($contextid, $component,
1351                         'incorrectfeedback', $question->id);
1352                 $expout .= "    <incorrectfeedback>\n";
1353                 $expout .= $this->writetext($question->options->incorrectfeedback, 3);
1354                 $expout .= $this->write_files($files);
1355                 $expout .= "    </incorrectfeedback>\n";
1357                 foreach ($question->options->answers as $answer) {
1358                     $percent = 100 * $answer->fraction;
1359                     $expout .= "<answer fraction=\"{$percent}\">\n";
1360                     // The "<text/>" tags are an added feature, old files won't have them.
1361                     $expout .= "    <text>{$answer->answer}</text>\n";
1362                     $expout .= "    <tolerance>{$answer->tolerance}</tolerance>\n";
1363                     $expout .= "    <tolerancetype>{$answer->tolerancetype}</tolerancetype>\n";
1364                     $expout .= "    <correctanswerformat>" .
1365                             $answer->correctanswerformat . "</correctanswerformat>\n";
1366                     $expout .= "    <correctanswerlength>" .
1367                             $answer->correctanswerlength . "</correctanswerlength>\n";
1368                     $expout .= "    <feedback {$this->format($answer->feedbackformat)}>\n";
1369                     $files = $fs->get_area_files($contextid, $component,
1370                             'instruction', $question->id);
1371                     $expout .= $this->writetext($answer->feedback);
1372                     $expout .= $this->write_files($answer->feedbackfiles);
1373                     $expout .= "    </feedback>\n";
1374                     $expout .= "</answer>\n";
1375                 }
1376                 if (isset($question->options->unitgradingtype)) {
1377                     $expout .= "    <unitgradingtype>" .
1378                             $question->options->unitgradingtype . "</unitgradingtype>\n";
1379                 }
1380                 if (isset($question->options->unitpenalty)) {
1381                     $expout .= "    <unitpenalty>" .
1382                             $question->options->unitpenalty . "</unitpenalty>\n";
1383                 }
1384                 if (isset($question->options->showunits)) {
1385                     $expout .= "    <showunits>{$question->options->showunits}</showunits>\n";
1386                 }
1387                 if (isset($question->options->unitsleft)) {
1388                     $expout .= "    <unitsleft>{$question->options->unitsleft}</unitsleft>\n";
1389                 }
1391                 if (isset($question->options->instructionsformat)) {
1392                     $files = $fs->get_area_files($contextid, $component,
1393                             'instruction', $question->id);
1394                     $expout .= "    <instructions " .
1395                             $this->format($question->options->instructionsformat) . ">\n";
1396                     $expout .= $this->writetext($question->options->instructions, 3);
1397                     $expout .= $this->write_files($files);
1398                     $expout .= "    </instructions>\n";
1399                 }
1401                 if (isset($question->options->units)) {
1402                     $units = $question->options->units;
1403                     if (count($units)) {
1404                         $expout .= "<units>\n";
1405                         foreach ($units as $unit) {
1406                             $expout .= "  <unit>\n";
1407                             $expout .= "    <multiplier>{$unit->multiplier}</multiplier>\n";
1408                             $expout .= "    <unit_name>{$unit->unit}</unit_name>\n";
1409                             $expout .= "  </unit>\n";
1410                         }
1411                         $expout .= "</units>\n";
1412                     }
1413                 }
1415                 // The tag $question->export_process has been set so we get all the
1416                 // data items in the database from the function
1417                 // qtype_calculated::get_question_options calculatedsimple defaults
1418                 // to calculated.
1419                 if (isset($question->options->datasets) && count($question->options->datasets)) {
1420                     $expout .= "<dataset_definitions>\n";
1421                     foreach ($question->options->datasets as $def) {
1422                         $expout .= "<dataset_definition>\n";
1423                         $expout .= "    <status>".$this->writetext($def->status)."</status>\n";
1424                         $expout .= "    <name>".$this->writetext($def->name)."</name>\n";
1425                         if ($question->qtype == 'calculated') {
1426                             $expout .= "    <type>calculated</type>\n";
1427                         } else {
1428                             $expout .= "    <type>calculatedsimple</type>\n";
1429                         }
1430                         $expout .= "    <distribution>" . $this->writetext($def->distribution) .
1431                                 "</distribution>\n";
1432                         $expout .= "    <minimum>" . $this->writetext($def->minimum) .
1433                                 "</minimum>\n";
1434                         $expout .= "    <maximum>" . $this->writetext($def->maximum) .
1435                                 "</maximum>\n";
1436                         $expout .= "    <decimals>" . $this->writetext($def->decimals) .
1437                                 "</decimals>\n";
1438                         $expout .= "    <itemcount>{$def->itemcount}</itemcount>\n";
1439                         if ($def->itemcount > 0) {
1440                             $expout .= "    <dataset_items>\n";
1441                             foreach ($def->items as $item) {
1442                                   $expout .= "        <dataset_item>\n";
1443                                   $expout .= "           <number>".$item->itemnumber."</number>\n";
1444                                   $expout .= "           <value>".$item->value."</value>\n";
1445                                   $expout .= "        </dataset_item>\n";
1446                             }
1447                             $expout .= "    </dataset_items>\n";
1448                             $expout .= "    <number_of_items>" . $def->number_of_items .
1449                                     "</number_of_items>\n";
1450                         }
1451                         $expout .= "</dataset_definition>\n";
1452                     }
1453                     $expout .= "</dataset_definitions>\n";
1454                 }
1455                 break;
1457             default:
1458                 // Try support by optional plugin.
1459                 if (!$data = $this->try_exporting_using_qtypes($question->qtype, $question)) {
1460                     $invalidquestion = true;
1461                 } else {
1462                     $expout .= $data;
1463                 }
1464         }
1466         // Output any hints.
1467         $expout .= $this->write_hints($question);
1469         // Write the question tags.
1470         // If the question has course tags then we need to filter them to only
1471         // include the tags for this course.
1472         get_question_options($question, true);
1473         if (isset($question->coursetagobjects)) {
1474             // Get the tag objects for the course being viewed.
1475             $courseid = $this->course->id;
1476             $coursecontext = context_course::instance($courseid);
1478             $coursetagobjects = array_filter(
1479                 $question->coursetagobjects,
1480                 function($tagobject) use ($coursecontext) {
1481                     return $coursecontext->id == $tagobject->taginstancecontextid;
1482                 }
1483             );
1485             // Set them on the form to be rendered as existing tags.
1486             $expout .= "    <coursetags>\n";
1487             foreach ($coursetagobjects as $tagobject) {
1488                 $expout .= "      <tag>" . $this->writetext($tagobject->get_display_name(), 0, true) . "</tag>\n";
1489             }
1490             $expout .= "    </coursetags>\n";
1491         }
1492         if (!empty($question->tags)) {
1493             $expout .= "    <tags>\n";
1494             foreach ($question->tags as $tag) {
1495                 $expout .= "      <tag>" . $this->writetext($tag, 0, true) . "</tag>\n";
1496             }
1497             $expout .= "    </tags>\n";
1498         }
1500         // Close the question tag.
1501         $expout .= "  </question>\n";
1502         if ($invalidquestion) {
1503             return '';
1504         } else {
1505             return $expout;
1506         }
1507     }
1509     public function write_answers($answers) {
1510         if (empty($answers)) {
1511             return;
1512         }
1513         $output = '';
1514         foreach ($answers as $answer) {
1515             $output .= $this->write_answer($answer);
1516         }
1517         return $output;
1518     }
1520     public function write_answer($answer, $extra = '') {
1521         $percent = $answer->fraction * 100;
1522         $output = '';
1523         $output .= "    <answer fraction=\"{$percent}\" {$this->format($answer->answerformat)}>\n";
1524         $output .= $this->writetext($answer->answer, 3);
1525         $output .= $this->write_files($answer->answerfiles);
1526         $output .= "      <feedback {$this->format($answer->feedbackformat)}>\n";
1527         $output .= $this->writetext($answer->feedback, 4);
1528         $output .= $this->write_files($answer->feedbackfiles);
1529         $output .= "      </feedback>\n";
1530         $output .= $extra;
1531         $output .= "    </answer>\n";
1532         return $output;
1533     }
1535     /**
1536      * Write out the hints.
1537      * @param object $question the question definition data.
1538      * @return string XML to output.
1539      */
1540     public function write_hints($question) {
1541         if (empty($question->hints)) {
1542             return '';
1543         }
1545         $output = '';
1546         foreach ($question->hints as $hint) {
1547             $output .= $this->write_hint($hint, $question->contextid);
1548         }
1549         return $output;
1550     }
1552     /**
1553      * @param int $format a FORMAT_... constant.
1554      * @return string the attribute to add to an XML tag.
1555      */
1556     public function format($format) {
1557         return 'format="' . $this->get_format($format) . '"';
1558     }
1560     public function write_hint($hint, $contextid) {
1561         $fs = get_file_storage();
1562         $files = $fs->get_area_files($contextid, 'question', 'hint', $hint->id);
1564         $output = '';
1565         $output .= "    <hint {$this->format($hint->hintformat)}>\n";
1566         $output .= '      ' . $this->writetext($hint->hint);
1568         if (!empty($hint->shownumcorrect)) {
1569             $output .= "      <shownumcorrect/>\n";
1570         }
1571         if (!empty($hint->clearwrong)) {
1572             $output .= "      <clearwrong/>\n";
1573         }
1575         if (!empty($hint->options)) {
1576             $output .= '      <options>' . $this->xml_escape($hint->options) . "</options>\n";
1577         }
1578         $output .= $this->write_files($files);
1579         $output .= "    </hint>\n";
1580         return $output;
1581     }
1583     /**
1584      * Output the combined feedback fields.
1585      * @param object $questionoptions the question definition data.
1586      * @param int $questionid the question id.
1587      * @param int $contextid the question context id.
1588      * @return string XML to output.
1589      */
1590     public function write_combined_feedback($questionoptions, $questionid, $contextid) {
1591         $fs = get_file_storage();
1592         $output = '';
1594         $fields = array('correctfeedback', 'partiallycorrectfeedback', 'incorrectfeedback');
1595         foreach ($fields as $field) {
1596             $formatfield = $field . 'format';
1597             $files = $fs->get_area_files($contextid, 'question', $field, $questionid);
1599             $output .= "    <{$field} {$this->format($questionoptions->$formatfield)}>\n";
1600             $output .= '      ' . $this->writetext($questionoptions->$field);
1601             $output .= $this->write_files($files);
1602             $output .= "    </{$field}>\n";
1603         }
1605         if (!empty($questionoptions->shownumcorrect)) {
1606             $output .= "    <shownumcorrect/>\n";
1607         }
1608         return $output;
1609     }