Balanced CMS Customer Survey Extension – Export survey results to .CSV

$this->addColumn('action',
    array(
        'header'    =>  Mage::helper('CustomerSurvey')->__('Action'),
        'width'     => '100',
        'type'      => 'action',
        'getter'    => 'getId',
        'actions'   => array(
            array(
                'caption'   => Mage::helper('CustomerSurvey')->__('Edit'),
                'url'       => array('base'=> '*/*/edit'),
                'field'     => 'id'
            ),
			array(
                'caption'   => Mage::helper('CustomerSurvey')->__('Results'),
                'url'       => array('base'=> '*/*/results'),
                'field'     => 'id'
            ),
			array(
                'caption'   => Mage::helper('CustomerSurvey')->__('Export Results to .csv'),
                'url'       => array('base'=> '*/*/csvexport'),
                'field'     => 'id'
            )
        ),
        'filter'    => false,
        'sortable'  => false,
        'index'     => 'stores',
        'is_system' => true,
));

public function csvExportAction() 
{
    $surveyid = $this->getRequest()->getParam('id');
 
    $file = Mage::getModel('customersurvey/results')->exportSurvey($surveyid);
    $this->_prepareDownloadResponse($file, file_get_contents(Mage::getBaseDir('export').'/'.$file));
}

/**
 * Get questions for survey
 * @return  (Array)
 */	
public function getMyQuestions($customersurveyId) 
{
	if($customersurveyId) {
		$questions  = Mage::getModel('customersurvey/questions')->getCollection()->addFieldToFilter('customersurvey_id', $customersurveyId);
		$questions = $questions->addAttributeToSort('sort_order', 'ASC');
	}
	else {
		$questions = array();	
	}
 
	return $questions;
}    
 
 
/**
 * Get responses given to survey
 * @return  (Array)
 */		
public function getMyResponses($customersurveyId) 
{
	if($customersurveyId) {
		//get the list of responses
		$groupedResponses = Mage::getModel('customersurvey/results')->getCollection();
 
		$groupedResponses->getSelect()->where("main_table.customersurvey_id = " . $customersurveyId)->group('main_table.input_time');
 
		//now for each response in the list, get the group of answers
		$responsesArray = array();
 
		foreach($groupedResponses as $groupedResponse) {
			$responses = Mage::getModel('customersurvey/results')->getCollection();
 
			$responses->getSelect()->where("main_table.customersurvey_id = " . $customersurveyId . " and main_table.input_time = '" . $groupedResponse->input_time . "'");
 
			$innerResponses = array();
			$innerResponses['input_time'] = $groupedResponse->input_time;
			$innerResponses['answers'] = array();
			foreach($responses as $response) {
				$innerResponses['answers'][$response->question_id] = $response->answer;
			}
 
			$responsesArray[] = $innerResponses;
		}
	}
	else
	{
		$responsesArray = array();	
	}
 
	return $responsesArray;
}	
 
 
/**
 * Writing head row to csv
 */	
public function exportSurvey($customersurveyId) 
{
	$this->surveyId = $customersurveyId;
	$fileName = 'survey_export_'.$customersurveyId.'.csv';
	$fp = fopen(Mage::getBaseDir('export').'/'.$fileName, 'w');
 
	// write first row for questions
	$this->writeHeadRow($fp);
 
	$myQuestions = $this->getMyQuestions($customersurveyId);
	$myResponses = $this->getMyResponses($customersurveyId);
 
	// write rows for answers in respected columns
	foreach($myResponses as $response) {
 
		$answers = array();
		array_push($answers,date("F j, Y g:i a", strtotime($response['input_time'])));
		foreach($myQuestions as $question) {
			if(key_exists($question->question_id,$response['answers'])) {
 
				$answer = $response['answers'][$question->question_id];
 
				switch($question->answer_type) {
				case "bubbles1":
				case "bubbles2":
				case "field": 
				case "area":		
					array_push($answers,$answer);
					break;
				case "star": 
					array_push($answers,$answer);
					break;
				case "yesno": 
					array_push($answers,$answer);
					break;
				case "customradio":
				case "checkboxes": 
					if($question->possible_answers) {
				        $possibleAnswers = explode('|||', $question->possible_answers);
				    }
				    else {
				    	array_push($answers,$answer);
				    	break;
				    }	        				
					$counterA = 0;
					$possibleAnswerArray = array();
					foreach($possibleAnswers as $possibleAnswer) {
						if(!(strpos($answer, " " . $counterA . ",") === false)) {
							array_push($possibleAnswerArray,$possibleAnswer);
						}
						$counterA++;	
					}
					if(count($possibleAnswerArray)>0) {
						array_push($answers,implode(', ',$possibleAnswerArray));	
					}
					break;
				default:
					array_push($answers,"");
					break;
				}
			}
			else {
				array_push($answers,"");
			}
		}
		if(count($answers) > 0) {
			fputcsv($fp, $answers, self::DELIMITER, self::ENCLOSURE);	
		}
	}
	fclose($fp);
	return $fileName;		
}
 
/**
 * Writing head row to csv
 */
protected function writeHeadRow($fp) 
{
	fputcsv($fp, $this->getHeadRowValues(), self::DELIMITER, self::ENCLOSURE);
}	
 
/**
 * Fetching questions to generate first row for csv.
 * @return  (Array)
 */
protected function getHeadRowValues() 
{
	$myQuestions = $this->getMyQuestions($this->surveyId);
 
	$questions = array();
 
	// Adding a column to capture date and time when survey was submitted.
	array_push($questions,"Date");
 
	foreach($myQuestions as $question) {
		array_push($questions,$question->question);
	}
	return $questions;
}