public function questionsbyTopicName($coursename, $subject, $chapterName, $topicName)
 {
     $topics = Topic::where('name', $topicName)->get();
     $topicID = null;
     if (count($topics) == 1) {
         $topicID = $topics->first()->id;
     } else {
         $subjects = Course::where('name', $coursename)->first()->subjects()->where('name', $subject)->get();
         $questions = collect([]);
         foreach ($subjects as $subject) {
             foreach ($subject->modules as $module) {
                 foreach ($module->chapters as $chapter) {
                     if ($chapter->name === $chapterName) {
                         foreach ($chapter->topics as $topic) {
                             if ($topic->name === $topicName) {
                                 $topicID = $topic->id;
                                 break 4;
                             }
                         }
                     }
                 }
             }
         }
     }
     return Question::where('topic_id', $topicID);
 }
 public function getfirst($typeid, $uuid)
 {
     // to get first element matching based on uuid
     switch ($typeid) {
         case 0:
             //Course
             return Course::where('id', $uuid)->first();
         case 1:
             //Subject
             # code...
             return Subject::where('id', $uuid)->first();
         case 2:
             //Module
             # code...
             return Module::where('id', $uuid)->first();
         case 3:
             //Cha[ter]
             # code...
             return Chapter::where('id', $uuid)->first();
         case 4:
             //Topic
             # code...
             return Topic::where('id', $uuid)->first();
         default:
             # code...
             break;
     }
 }
 public function gettopics($chapterid)
 {
     return Topic::where('ref_id', $chapterid)->get();
 }