<?php

class SurveyRDFWriter 
{
    protected $model;

    protected $resourceSurvey;
    protected $surveyUID;

    protected $filePath;

    public function __construct($surveyUID)
    {
        // Create empty MemModel
        $factory = new ModelFactory();
        $this->model = $factory->getDefaultModel();

        $this->surveyUID = $surveyUID;	
        $this->filePath = 'data/surveys/';
        if (!is_dir($this->filePath))
            mkdir($this->filePath);	
    }	

    public function saveSurvey()
    {	
        $this->model->saveAs($this->filePath.'survey_'.$this->surveyUID.'.rdf','rdf');
    }

    public function createSurvey($sTitle, $sDescription)
    {		
        $this->resourceSurvey = new Resource(SURVEY.'/'.$this->surveyUID);

        $resourceSurveyType = new Resource(SURVEY);
        $predicateRType = new Resource(RTYPE);
        $this->model->add(new Statement($this->resourceSurvey,$predicateRType,$resourceSurveyType));

        $literalSurveyID = new Literal($this->surveyUID);
        $predicateUniqueID = new Resource(UID);
        $this->model->add(new Statement($this->resourceSurvey,$predicateUniqueID,$literalSurveyID));

        $predicateTitle = new Resource(TITLE);		
        $surveyTitle = new Literal($sTitle);
        $this->model->add(new Statement($this->resourceSurvey,$predicateTitle,$surveyTitle));		

        $predicateDescription = new Resource(DESCRIPTION);
        $surveyDescription = new Literal($sDescription);
        $this->model->add(new Statement($this->resourceSurvey,$predicateDescription,$surveyDescription));		
    }

    public function setUserData($userID)
    {				
        $resourceUser = new Resource(USER . '/' . $userID);

        $predicateCreator = new Resource(CREATOR);
        $this->model->add(new Statement($this->resourceSurvey,$predicateCreator,$resourceUser));
    }

    public function addQuestion($qTitle,$qDescription,$qType,$qID,$qAnswers)
    {
        $questionID = $qID;
        $resourceQuestion = new Resource(QUESTION.'/'.$questionID);

        $resourceQuestionType = new Resource(QUESTION);
        $predicateRType = new Resource(RTYPE);
        $this->model->add(new Statement($resourceQuestion,$predicateRType,$resourceQuestionType));

        $predicateUniqueID = new Resource(UID);
        $questionUID = new Literal($questionID);
        $this->model->add(new Statement($resourceQuestion,$predicateUniqueID,$questionUID));

        $predicateTitle = new Resource(TITLE);		
        $questionTitle = new Literal($qTitle);
        $this->model->add(new Statement($resourceQuestion,$predicateTitle,$questionTitle));	

        $predicateDescription = new Resource(DESCRIPTION);
        $questionDescription = new Literal($qDescription);
        $this->model->add(new Statement($resourceQuestion,$predicateDescription,$questionDescription));		

        $predicateQType = new Resource(QTYPE);
        $resourceQuestionType = new Literal($qType);
        $this->model->add(new Statement($resourceQuestion,$predicateQType,$resourceQuestionType));

            foreach($qAnswers as $answer)
            {		
                $answerID = md5( uniqid(rand(), true) );	
                $resourceAnswer = new Resource(ANSWER.'/'.$answerID);

                $resourceAnswerType = new Resource(ANSWER);
                $predicateRType = new Resource(RTYPE);
                $this->model->add(new Statement($resourceAnswer,$predicateRType,$resourceAnswerType));	

                $predicateUniqueID = new Resource(UID);
                $answerUID = new Literal($answerID);
                $this->model->add(new Statement($resourceAnswer,$predicateUniqueID,$answerUID));			

                $answerTitle = new Literal($answer['Title']);
                $this->model->add(new Statement($resourceAnswer,$predicateTitle,$answerTitle));

                $answerDescription = new Literal($answer['Description']);
                $this->model->add(new Statement($resourceAnswer,$predicateDescription,$answerDescription));

                $predicateAnswer = new Resource(HAS_ANSWER);	
                $this->model->add(new Statement($resourceQuestion,$predicateAnswer,$resourceAnswer));
            }

            $predicateQuestion = new Resource(HAS_QUESTION);
            $this->model->add(new Statement($this->resourceSurvey,$predicateQuestion,$resourceQuestion));		
        }
}

?>