/**
  * @param int $exerciseId
  * @param int $mediaId
  * @return array
  */
 public function getQuestionCategoriesOfMediaQuestions($exerciseId, $mediaId)
 {
     $questions = $this->getQuestionsPerMediaWithCategories($exerciseId, $mediaId);
     $questionCategoryList = array();
     if (!empty($questions)) {
         foreach ($questions as $question) {
             $categories = TestCategory::getCategoryForQuestionWithCategoryData($question['iid']);
             if (!empty($categories)) {
                 foreach ($categories as $category) {
                     $questionCategoryList[$question['iid']][] = $category['iid'];
                 }
             }
         }
     }
     return $questionCategoryList;
 }