Core File for Plugin

<?php

/**
 * Core class for handling functionality requried throught the plugin.
 *
 * @author Iain Cambridge
 * @copyright Fubra Limited 2010-2011 (c)
 * @license http://www.gnu.org/licenses/gpl.html GPL v3
 */

class Wpsqt_Core {

	protected $_pages = array();

	/**
	 * Adds the generic hooks that are required throughout
	 * the plugin.
	 *
	 * @since 2.0
	 */

	public function __construct(){

		$this->_addPage(WPSQT_PAGE_MAIN, "WPSQT", "WPSQT", "wpsqt-manage", "Main")
		->_addPage(WPSQT_PAGE_MAIN.'&type=quiz', "Quizzes", "Quizzes", "wpsqt-manage", "Quizzes", WPSQT_PAGE_MAIN)
		->_addPage(WPSQT_PAGE_MAIN.'&type=survey', "Surveys", "Surveys", "wpsqt-manage", "Surveys", WPSQT_PAGE_MAIN)
		->_addPage(WPSQT_PAGE_MAIN.'&type=poll', "Polls", "Polls", "wpsqt-manage", "Polls", WPSQT_PAGE_MAIN)
		->_addPage(WPSQT_PAGE_OPTIONS, "Options", "Options", "wpsqt-manage", "Options", WPSQT_PAGE_MAIN)
		->_addPage(WPSQT_PAGE_MAINTENANCE, 'Maintenance', 'Maintenance', 'wpsqt-manage', 'Maintenance', WPSQT_PAGE_MAIN)
		->_addPage(WPSQT_PAGE_HELP, "Help", "Help", "wpsqt-manage", "Help",WPSQT_PAGE_MAIN);

		add_action("init",array($this, "create_nonce" ) );
		add_action("wp_footer",array($this,"show_footer"));

		add_shortcode( 'wpsqt_quiz' , array($this, 'shortcode_quiz') );
		add_shortcode( 'wpsqt_survey' , array($this, 'shortcode_survey') );
		add_shortcode( 'wpsqt' , array($this, 'shortcode') );
		add_shortcode( 'wpsqt_results', array($this, 'shortcode_results') );
		add_shortcode( 'wpsqt_survey_results', array($this, 'shortcode_survey_results') );

		add_action('init', array($this,"init"));
		add_action('admin_bar_menu', array($this,"adminbar"),999);
		add_action( 'init' , array($this,"enqueue_files"));

		// Register the top scores widget
		require_once WPSQT_DIR.'lib/Wpsqt/Widget.php';
		add_action( 'widgets_init', create_function('', 'return register_widget("Wpsqt_Top_Widget");') );
	}


	/**
	 * Quick, easy and neat way to add new pages to
	 * the plugin without having to edit multiple files
	 * in multiple places.
	 *
	 * @param string $id the page identifier
	 * @param string $title The menu title
	 * @param string $pageTitle The Page title.
	 * @param string $cap The capaiblity required to access the menu item.
	 * @param string $module The Module that relates to the class that holds the logic for the page.
	 * @param string|null $parent Parent identifier, if null it is a parent.
	 * @since 2.0
	 * @return Wpsqt_Core
	 */

	protected function _addPage($id,$title,$pageTitle,$cap,$module,$parent = null){

		$this->_pages[$id] = array("title" => $title,
			"page_title" => $pageTitle,
			"capability" => $cap,
			"module" => $module,
			"parent" => $parent);

		return $this;

	}

	/**
	 * Hook to allow people to extend the plugin
	 * using filter to interact with the object.
	 *
	 * @since 2.0
	 */

	public function init(){

		apply_filters("wpsqt_init",$this);

		if ( isset($_SESSION['wpsqt']) ) {
			unset($_SESSION['wpsqt']['current_message']);
		}
	}

	/**
	 * Adds the WPSQT Menu items to the admin bar.
	 * Because we're cool like that.
	 *
	 * @param WP_Admin_bar $wp_admin_bar
	 */

	public function adminbar( $wp_admin_bar) {

		if ( current_user_can("manage_options") ) {
			foreach ( $this->_pages as $pagevar => $page ){
				$wp_admin_bar->add_menu( array( 'title' => $page['title'], 'href' => admin_url('admin.php?page='.$pagevar), 'id' => $pagevar, 'parent' => $page['parent']));
			}

		}
	}

	/**
	 * Creates the current nonce and checks to see if a nonce field
	 * has been sent and if so if it is valid.
	 *
	 * @since 2.0
	 */

	public function create_nonce(){

		if ( isset($_REQUEST["wpsqt_nonce"]) ){
			$validNonce = wp_verify_nonce($_REQUEST["wpsqt_nonce"],'wpsqt_nonce');
		} else {
			$validNonce = false;
		}

		define( "WPSQT_NONCE_VALID" , $validNonce );
		define( "WPSQT_NONCE_CURRENT" , wp_create_nonce('wpsqt_nonce') );

	}

	/**
	 * Checks to see if their is a valid nonce if not
	 * then calls wp_die();
	 *
	 * @since 2.0
	 */

	public static function validNonce(){

		if ( WPSQT_NONCE_VALID != true ){
			wp_die("Invalid nonce field, either your session has timed out or someone has tried to trick you with a cross site request.");
		}

	}

	/**
	 * Checks to see if the a custom page view exists
	 * and if so it uses that. Checks the directory of
	 * the quiz or survey's custom pages. If no file
	 * exists checks the shared custom directory else
	 * it returns the location of the default page view.
	 *
	 * Note: All plugin page views can be replaced using
	 * this functionality.
	 *
	 * @param string $file the location of the page view file.
	 * @since 2.0
	 * @return string the location of the page view.
	 */

	public static function pageView($file){

		global $blog_id;

		$quizPath = ( isset($_SESSION['wpsqt']['item_id'])
			&& ctype_digit($_SESSION['wpsqt']['item_id']) ) ?
			$blog_id.'/'.$_SESSION['wpsqt']['current_type'].'-'.$_SESSION['wpsqt']['item_id'].'/' : '';

		if ( file_exists(WPSQT_DIR.'pages/custom/'.$quizPath.$file) ){
			return WPSQT_DIR.'pages/custom/'.$quizPath.$file;
		} elseif (file_exists(WPSQT_DIR.'pages/custom/'.$blog_id.'/shared/'.$file)) {
			return WPSQT_DIR.'pages/custom/'.$blog_id.'/shared/'.$file;
		}
		return WPSQT_DIR.'pages/'.$file;

	}

	/**
	 * Gets the number of page based eon the number
	 * of items there are and the number of items
	 * per page.
	 *
	 * @param integer $numberOfItems the total number of items.
	 * @param integer $itemsPerPage the number of items we want on a page.
	 * @return integer Returns the number of pages required to display $numberOfItems with $itemsPerPages per page
	 * @since 2.0
	 */

	public static function getPaginationCount($numberOfItems,$itemsPerPage){

		if ( $numberOfItems > 0 ){
			$numberOfPages = intval( $numberOfItems / $itemsPerPage );

			if ( $numberOfItems % $itemsPerPage ){
				$numberOfPages++;
			}
		} else {
			$numberOfPages = 0;
		}

		return $numberOfPages;
	}

	/**
	 * Generates a usable Uri for adding new get variables. Allows
	 * for easy page links. Excludes certain get variables from the
	 * uri if they are present in the $exclude array.
	 *
	 * @param array $exclude the items which we want to exclude from the uri.
	 * @since 2.0
	 */

	public static function generateUri( array $exclude = array() ){

		$returnString = $_SERVER['PHP_SELF'].'?';
		if ( !empty($_GET) ){
			foreach ( $_GET as $varName => $varValue ){
				if ( !in_array($varName, $exclude) ){
					$returnString .= $varName.'='.$varValue.'&';
				}
			}
		}

		return $returnString;
	}

	/**
	 * Generates the pagination links. Shows 5 links in total. Two on either side
	 * if possible.
	 *
	 * @return $returnString the html with the links.
	 * @since 2.0
	 */

	public static function getPaginationLinks($currentPage,$numberOfPages){

		$returnString = '';
		$pageUri = self::generateUri( array('pageno') );

		for($i = 1; $i <= $numberOfPages; $i ++) {
			if ($i == $currentPage) {
				$returnString .= ' <a href="'.$pageUri.'pageno='.$i.'" class="page-numbers current">'.$i.'</a>';
			} else {
				$returnString .= ' <a href="'.$pageUri.'pageno='.$i.'" class="page-numbers">'.$i.'</a>';
			}
		}

		return $returnString;
	}

	/**
	 * Returns the integer value of $_GET['pageno'] while ensuring
	 * that it is set and is a number. Otherwise returns 1.
	 *
	 * @since 2.0
	 */

	public static function getCurrentPageNumber(){

		if ( isset($_GET['pageno']) && ctype_digit($_GET['pageno']) ){
			$pageNumber = (int)$_GET['pageno'];
		}
		else{
			$pageNumber = 1;
		}

		return $pageNumber;

	}

	/**
	 * Adds the CatN's link to the footer if the
	 * user agrees to it.
	 *
	 * @since 2.0
	 */

	public function show_footer(){

		echo '<!-- Survey and Quizzes Powered by WP Survey And Quiz Tool '.WPSQT_VERSION.' iain.cambridge at fubra.com -->';

		if ( get_option('wpsqt_support_us') == 'yes'){
			echo '<p style="text-align: center;"><a href="http://catn.com/">Get Cloud PHP Hosting on CatN</a></p>';
		}

	}

	/**
	 * Returns the possible locations of class files like Wpsqt_Page and
	 * Wpsqt_Question child classes.
	 *
	 * @param string $className The name of the class that is to be included.
	 * @since 2.0
	 */

	public static function getObject($className , $fatal = true){

		$possibleLocations = array();
		$possibleLocations[] = WPSQT_DIR.'lib/';
		$possibleLocations = apply_filters('wpsqt_plugin_locations',$possibleLocations);

		foreach ( $possibleLocations as $locus ){

			$location = $locus.str_replace(" ", "_", str_replace("_","/",$className)).".php";

			if ( file_exists($location) ){
				require_once $location;
				break;
			}
		}

		if ( !class_exists($className) ){
			if ( $fatal === true ){
				wp_die("No such ".$className." class");
			} else {
				return false;
			}
		}

		$object = new $className();

		return $object;
	}


	public function shortcode_survey( $atts ){

		if ( empty($atts) ){
			return;
		}

		extract( shortcode_atts( array(
					'name' => false
				), $atts) );

		return $this->_shortcode($name, 'survey');

	}

	public function shortcode_quiz( $atts ) {

		if ( empty($atts) ){
			return;
		}

		extract( shortcode_atts( array(
					'name' => false
				), $atts) );

		return $this->_shortcode($name, 'quiz');

	}


	/**
	 * Method for new shortcode that will allow for type handler option.
	 *
	 * @param array $atts
	 * @since 2.2.2
	 */
	public function shortcode($atts) {
		if (empty($atts)) {
			return;
		}

		extract( shortcode_atts( array(
					'name' => false,
					'type' => false
				), $atts) );

		return $this->_shortcode($name, $type);
	}

	/**
	 * DRY method to show return the quizzes and surveys in the correct location.
	 *
	 * @param string $identifer The name or numerical id of the quiz/survey
	 * @param string $type If it is a quiz or a survey.
	 * @since 2.2.2
	 */
	protected function _shortcode($identifer,$type)	{
		ob_start();

		require_once WPSQT_DIR.'lib/Wpsqt/Shortcode.php';
		$objShortcode = new Wpsqt_Shortcode($identifer, $type);
		$objShortcode->display();

		$content = ob_get_contents();
		ob_end_clean();

		return $content;
	}

	public function shortcode_results( $atts ) {
		global $wpdb;
		extract( shortcode_atts( array(
					'username' => false,
					'accepted' => false
		), $atts) );
		if ($username != false) {
			$sql = 'SELECT * FROM `'.WPSQT_TABLE_RESULTS.'` WHERE `person_name` = "'.$username.'"';
			if ($accepted != false)
				$sql .=  'AND `status` = "Accepted"';
			$return = $wpdb->get_results($sql, 'ARRAY_A');
			if (empty($return))
				echo '<p>'.$username.' has no results</p>';
			foreach ($return as $result) {
				$sql = 'SELECT * FROM `'.WPSQT_TABLE_QUIZ_SURVEYS.'` WHERE `id` = "'.$result['item_id'].'"';
				$return = $wpdb->get_results($sql, 'ARRAY_A');
				if (empty($return)) {
					continue;
				}
				return  "<h3>Results for ".$return[0]['name']."</h3>".
						"<p>Score: ".$result['score']."/".$result['total']."</p>".
						"<p>Percentage: ".$result['percentage']."</p>".
						"<br /><br />";
			}
		} else {
			return 'No username was supplied for this results page. The shortcode should look like [wpsqt_results username="admin"]';
		}
	}

	public function shortcode_survey_results( $atts ) {
		global $wpdb;
		extract( shortcode_atts( array(
					'name' => false
		), $atts) );
		if ($name == false) {
			echo 'No survey name was supplied.';
		} else {
			echo 'Results for '.$name;

			// Get the ID
			$surveyId = $wpdb->get_row("SELECT `id` FROM `".WPSQT_TABLE_QUIZ_SURVEYS."` WHERE `name` = '".$name."'", ARRAY_A);
			$surveyId = (int) $surveyId['id'];

			// Get results
			$result = $wpdb->get_row("SELECT * FROM `".WPSQT_TABLE_SURVEY_CACHE."` WHERE item_id = '".$surveyId."'", ARRAY_A);
			$sections = unserialize($result['sections']);
			foreach($sections[0]['questions'] as $questionKey => $question) {
				if ($question['type'] == 'Free Text') {
					$uncachedResult = $wpdb->get_results(
						$wpdb->prepare("SELECT * FROM `".WPSQT_TABLE_RESULTS."` WHERE item_id = %d",
									   array($_GET['id'])), ARRAY_A
									);
					$uncachedresults = $uncachedResult;
					// Storing all the IDs for free text questions
					$freetextq[] = $questionKey;
				}
			}
			// Just reuse the same page view that the admin thing uses
			require_once WPSQT_DIR.'pages/admin/surveys/result.total.script.php';
		}
	}

	public function enqueue_files() {
		wp_enqueue_script("jquery");
		wp_enqueue_style("wpsqt-main",plugins_url('/css/main.css',WPSQT_FILE));
	}
}