<?php
// Survey database interface class as intermediate for storing data from the site to the RDF database 
require_once 'rdfConstants.php';
// Include RAP Library to write RDF files
include(RDFAPI_INCLUDE_DIR . "RDFAPI.php");
/**
 * Description of Application
 *
 * @author jkraaijeveld
 */
class Application extends ResearchToolObject{
    
	public static $filename = 'data/applications/applications.rdf';

    public $title;
    public $description;
    public $style;

	/**
	 * Constructor for an Application object
	 * @param type $uid : The uid of the Application object.
	 * @param type $title: The title of the Application.
	 * @param type $description: The description of the Application.
	 * @param type $style: The style of the Application.
	 */
    public function __construct($uid = null, $title = null, $description = null, $style = null) 
    {
        if(!isset ($uid))
        {
            $uid = md5(uniqid(rand(), true));
        }
        $this->uid = $uid;
        $this->title = $title;
        $this->description = $description;
		$this->style = $style;
	}
	
	/**
	 * function save()
	 * Saves the current object into the database.
	 */
	public function save()
	{
		//Ensure the required folder exists.
		if(!is_dir('data/applications/'))
			mkdir('data/applications/');

		$model = ResearchToolObject::load(Application::$filename);
        $resourceApplication = new Resource(APPLICATION.'/'.$this->uid);
        //Remove the old value stored with the given id
        $model->subtract($model->find($resourceApplication, null, null));

        //Add the new statements to the model
        $resourceApplicationType = new Resource(APPLICATION);
        $predicateRType = new Resource(RTYPE);
        $model->add(new Statement($resourceApplication,$predicateRType,$resourceApplicationType));
		
        $literalApplicationID = new Literal($this->uid);
        $predicateUniqueID = new Resource(UID);
        $model->add(new Statement($resourceApplication,$predicateUniqueID,$literalApplicationID));

        $applicationTitle = new Literal($this->title);
        $predicateTitle = new Resource(TITLE);	
        $model->add(new Statement($resourceApplication,$predicateTitle,$applicationTitle));

        $applicationDescription = new Literal($this->description);
        $predicateDescription = new Resource(DESCRIPTION);
        $model->add(new Statement($resourceApplication,$predicateDescription,$applicationDescription));

        $applicationStyle = new Literal($this->style);
        $predicateStyle = new Resource(STYLE);
        $model->add(new Statement($resourceApplication,$predicateStyle,$applicationStyle));
		
		$model->saveAs(Application::$filename, 'rdf');
		return true;
	}

	/**
	 * static function get($arguments)
	 * Gets the array of Application objects belonging to arguments supplied.
	 * @param type $arguments : An array containing zero or more of the following keys:
	 * 							'uid', 'title', 'description', 'style'
	 */
	public static function get($arguments)
	{
		$model = ResearchToolObject::load(Application::$filename);
		 //Create the querystring 
        $querystring = '
            PREFIX  predicates: <' . SURVEYTOOL_PREDICATES_NAMESPACE . '>
            PREFIX  resources: <' . SURVEYTOOL_RESOURCES_NAMESPACE . '>
            SELECT ?uid, ?title, ?description, ?style
            WHERE 	
            {
                    _application	predicates:resource_type	resources:application ;
					predicates:uid ?uid ;
					predicates:title ?title ;
					predicates:description ?description ;
					predicates:style ?style ; '
                    . ResearchToolObject::createArguments($arguments) . ' 
            }';

        //Query the model
        $results = $model->sparqlQuery($querystring);
        $applications = array();
        if(!empty($results))
        {
            //Run over all results and create appropriate Application objets
            foreach($results as $result)
            { 
                    $applications[] = new Application($result['?uid']->label, $result['?title']->label, $result['?description']->label, $result['?style']->label);
            }
        }
        return $applications;
	}
}

?>