private function isSurveyDuplicated(&$survey, $account){
       
        $survey_check = new Application_Model_Survey($this->db);
        $result = $survey_check->checkSurveyExist($survey->getSubject(), $survey->getTag(), $survey->getPronoun());
        if($result) {
            /* so there is the same survey already in the database 
             *  -instead fo creating new - add recipient to this survey
             *  the survey is now loaded in $survey_check object
             */
            $new_survey_responders = $survey->getResponderEmails();
            $existing_survey_reposnders = $survey_check->getResponderEmails();
            $responders_to_add = array();
            foreach($new_survey_responders as $new){
                if(!in_array($new, $existing_survey_reposnders)) {
                    $responders_to_add[] = $new;
                }
            }
            $all_responders = array_merge($existing_survey_reposnders, $responders_to_add);
            
            //if there is no new emails to add to survey, then it's look like this is duplicated request
            //so do nothing with this and prevent to send duplicated confirmation
            if(count($responders_to_add) <= 0) {
                 return true;
            } else {
                //check if there are still place to add new recipients according to account max recipients constant
                
                if($account->getAccountMaxRecipients() >= count($all_responders)) {
                    //IF THERE IS PLACE then add new recipients to existing survey and mark as duplicated, so the confirmation email will not be send twice
                    foreach($responders_to_add as $responder){
                        $survey_check->addResponder($responder);
                    }
                    $survey_check->save();
                    return true;
                } else {
                    //IF THERE ARE NO PLACE FOR NEW RESPONDERS, then new survey should be created - so return this as not duplicated
                    return false;
                }
            }
            
            $survey = $survey_check;
            return true;
        } else {
            return false;
        }
   }