private $temp = ''; //temp directory used to save files

private $question_count = 0; //number of questions written to the file so far

/**

* log for logging message, errors, etc.

* @var Log

*/

private $log = null;

/**

* Manifest writer

* @var ImsCpmanifestWriter

*/

private $manifest = null;

/**

* Manifest ressources writer

* @var ImsCpmanifestWriter

*/

private $manifest_resources = null;

private $manifest_organization = null;

public function __construct($log = null){

$this->log = empty($log) ? LogEmpty::instance() : $log;

$this->init();

}

public function get_question_count(){

return $this->question_count;

}

public function init(){

$this->question_count = 0;

$this->manifest = new ImsCpmanifestWriter();

$manifest = $this->manifest->add_manifest();

$this->manifest_organization = $manifest->add_organizations()->add_organization();

$this->manifest_resources = $manifest->add_resources();

if (!$this->temp = MoodleUtil::create_temp_directory()){

return $this->notify_lang('cannotcreatepath');

}else{

return true;

}

}

public function add_quiz($quiz){

$questions = $this->get_quiz_questions($quiz);

$questions = $this->add($questions);

$serializer = new QuizSerializer();

$text = $serializer->serialize($quiz, $questions);

$filepath = $this->get_quiz_filepath($quiz);

$this->write($filepath, $text);

$this->add_manifest_quiz($quiz);

return $filepath;

}

public function add_questions($category, $include_category = false, $include_hidden = false){

$questions = $this->get_questions($category, $include_category, $include_hidden);

foreach($questions as $question){

$this->add($question);

}

}

public function add($question){

if(is_array($question)){

$result = array();

foreach($question as $q){

if($r = $this->add($q)){

foreach($r as $filepath=>$qq)

$result[$filepath] = $qq;

}

}

return $result;

}else{

// $this->notify_lang('export', '', $question);

$filepath = $this->get_question_filepath($question);

if(! $serializer = $this->create_serializer($question)){

return $this->notify_lang('unknownquestiontype', '', $question);

}else if(! $text = $serializer->serialize($question)){

return $this->notify_lang('error', '', $question);

}else if(!$this->write($filepath, $text)){

return $this->error('cannotwriteto', '', $filepath);

}else{

$manifest_resource = $this->add_manifest_question($question);

$resources = $serializer->get_resources();

$this->export_resources($resources);

foreach($resources as $href => $url){

$manifest_resource->add_file($href);

}

$this->question_count++;

return array($filepath=>$question);

}

}

}

public function save(){

$this->manifest->save($this->temp .'/'. ImsCpmanifestWriter::MANIFEST_NAME);

$zipfile = $this->temp . '/export.zip';

$result = MoodleUtil::archive_directory($this->temp, $zipfile);

$zipcontent = file_get_contents($zipfile);

// Remove the temporary directory.

fulldelete($this->temp);

return $zipcontent;

}

public function get_questions($category, $include_category = false, $include_hidden = false){

$result = array();

$questions = get_questions_category($category);

foreach($questions as $question){

if((!$question->hidden || $include_category) && ($question->parent == 0 || $include_hidden)){

$result[] = $question;

}

}

return $result;

}

public function get_quiz_questions($quiz){

$id = is_object($quiz) ? $quiz->id : $quiz;

global $DB;

global $CFG;

$prefix = $CFG->prefix;

$sql = 'SELECT q.* FROM {question} q, {quiz_question_instances} i

WHERE

i.quiz = ' . $id .' AND

q.id = i.question';

try{

$result = $DB->get_records_sql($sql);

if(is_array($result)){

foreach($result as $question){

$question->export_process = true;//needed to export datasets

}

}

get_question_options($result, true);

}catch(Exception $e){

debug($e);

}

return $result;

}

protected function write($path, $content){

return FileUtil::write($path, $content);

}

protected function export_resources($ressources){

$directory = $this->temp;

foreach($ressources as $target => $url){

$path = $directory.$target;

FileUtil::ensure_directory($path);

$url = explode('/', $url);

$question_id = reset($url);

$category_id = $url[1];

$filename = end($url);

$context = $this->get_context_by_category_id($category_id);

$fs = get_file_storage();

if($file = $fs->get_file($context->id, 'question', 'questiontext', $question_id, '/', $filename)){

$file->copy_content_to($path);

}

}

}

function get_context_by_category_id($category) {

global $DB;

$contextid = $DB->get_field('question_categories', 'contextid', array('id'=>$category));

$context = context::instance_by_id($contextid);

return $context;

}

protected function create_serializer($question){

return QuestionSerializer::factory($question, 'resources');

}

protected function get_question_filename($question){

return $this->get_question_name($question) . '.xml';

}

protected function get_question_name($question){

return 'q_'. str_pad($question->id, 8, '0', STR_PAD_LEFT);

}

protected function get_question_filepath($question){

return $this->temp .'/'. $this->get_question_filename($question);

}

protected function get_quiz_filepath($quiz){

return $this->temp .'/'. 'quiz_'. str_pad($quiz->id, 8, '0', STR_PAD_LEFT) . '.xml';

}

protected function add_manifest_question($question){

$type = 'imsqti_item_xmlv2p0';

$id = $this->get_question_name($question);

$href = $this->get_question_filename($question);

$result = $this->manifest_resources->add_resource($type, $href, $id);

$this->add_question_metadata($result, $question);

$result->add_file($href);

$this->manifest_organization->add_item($id)->add_title($question->name);

return $result;

}

protected function add_manifest_quiz($quiz){

$type = 'imsqti_item_xmlv2p0';

$path = $this->get_quiz_filepath($quiz);

$id = basename($path);

$href = basename($path);

$result = $this->manifest_resources->add_resource($type, $href, $id);

//$this->add_question_metadata($result, $question);

$result->add_file($href);

$this->manifest_organization->add_item($id)->add_title($quiz->name);

return $result;

}

protected function add_question_metadata(ImsXmlWriter $item, $question){

$result = $item->add_metadata('lom', '1.0');

$lom = new LomWriter($result, 'lom');

$general = $lom->add_general();

$general->add_title($question->name);

$general->add_identifier(MoodleUtil::get_catalog_name(), $question->id);

$lifecycle = $lom->add_lifecycle();

$lifecycle->add_status();

return $result;

}

protected function notify_lang($message, $module, $a){

$module = empty($module) ? 'quiz' : $module;

$question_text = is_object($a) ? "$a->id - $a->name ($a->qtype)" : '';

$a = is_object($a) ? '' : $a;

$text = get_string($message, $module, $a);

$text = empty($question_text) ? $text : "$text : $question_text";

$this->log->notify($text);

return false;

}