wpit-utility.php

<?php
/*
Plugin Name: WPIT Utility
Description: Here goes all custom utility
Author: Wolly, xlthlx, flodolo
Version: 1.0
*/

define ( 'WPIT_UTILITY_PLUGIN_PATH', plugin_dir_path( __FILE__ ) );
define ( 'WPIT_UTILITY_PLUGIN_DIR', plugin_dir_url( __FILE__ ) );
define ( 'WPIT_UTILITY_PLUGIN_SLUG', basename( dirname( __FILE__ ) ) );
define ( 'WPIT_UTILITY_PLUGIN_VERSION', '1.0' );
define ( 'WPIT_UTILITY_PLUGIN_VERSION_NAME', 'wpit_utility_version' );

//include option panel
include_once 'inc/class-wpit-utility-options.php';

class Wpit_Utility {

	//A static member variable representing the class instance
	private static $_instance = null;
	
	private $options;

	/**
	 * Wpit_Utility::__construct()
	 * Locked down the constructor, therefore the class cannot be externally instantiated
	 *
	 * @param array $args various params some overidden by default
	 *
	 * @return
	 */

	private function __construct() {
		
		//get options
		$this->options = get_option( 'wpit-options' );
		
		// init actions (update)...
		add_action( 'init', array( $this, 'update_check' ) );

		//Add GA script in footer
		if ( 'footer' != $this->options['footer'] ){
			add_action( 'wp_head', array( $this, 'add_googleanalytics' ) );
		} else {
			add_action( 'wp_footer', array( $this, 'add_googleanalytics' ) );
		}
		
		// Use youtube-nocookies for oEmbed of YouTube videos
		add_filter( 'embed_oembed_html', 'youtube_oembed_nocookie', 10, 4 );
		
		//remove WordPress capitalization
		remove_filter( 'the_title', 'capital_P_dangit', 11 );
		remove_filter( 'the_content', 'capital_P_dangit', 11 );
		remove_filter( 'comment_text', 'capital_P_dangit', 31 );

        // Shortcodes...
        add_shortcode( 'placeholder', array( $this, 'placeholder_creator' ) );


    }

	/**
	 * Wpit_Utility::__clone()
	 * Prevent any object or instance of that class to be cloned
	 *
	 * @return
	 */
	public function __clone() {
		trigger_error( "Cannot clone instance of Singleton pattern ...", E_USER_ERROR );
	}

	/**
	 * Wpit_Utility::__wakeup()
	 * Prevent any object or instance to be deserialized
	 *
	 * @return
	 */
	public function __wakeup() {
		trigger_error( 'Cannot deserialize instance of Singleton pattern ...', E_USER_ERROR );
	}

	/**
	 * Wpit_Utility::getInstance()
	 * Have a single globally accessible static method
	 *
	 * @param mixed $args
	 *
	 * @return
	 */
	public static function getInstance( $args = array() ) {
		if ( ! is_object( self::$_instance ) )
			self::$_instance = new self( $args );

		return self::$_instance;
	}

	/**
	 * update_UTILITY_check function.
	 *
	 * @access public
	 * @return void
	 */
	public function update_check() {
		// Do checks only in backend
		if ( is_admin() ) {
	
			if ( version_compare( get_site_option( WPIT_UTILITY_VERSION_NAME ), WPIT_UTILITY_VERSION ) != 0  ) {
	
			$this->do_update();
	
			}
	
		} //end if only in the admin
	}
	
	/**
	 * do_update function.
	 *
	 * @access private
	 *
	 */
	private function do_update(){
	
		//DO NOTHING, BY NOW, MAYBE IN THE FUTURE
	
		//Update option
	
		update_option( WPIT_UTILITY_VERSION_NAME , WPIT_UTILITY_VERSION_NUMBER_VERSION );
	
	}
	
	/**
	 * add_googleanalytics function.
	 *
	 * insert the GA script
	 *
	 * @access public
	 *
	 */
	public function add_googleanalytics(){ 
		?>
		
		<!-- GA code inserted by WPIT Utility plugin-->
		<?php echo $this->options['ga_ua']; ?>
		<!-- END GA code inserted by WPIT Utility plugin-->
		<?php	
	}
	
	
	/**
	 * youtube_oembed_nocookie function.
	 * 
	 * @access public
	 * @param string $html    Google Video HTML embed markup.
   	 * @param string $url     The attempted embed URL.
    	 * @param array  $attr    An array of shortcode attributes.
	 * @param int    $post_ID Post ID.
	 * 
	 * @return $content
	 */
	function youtube_oembed_nocookie($html, $url, $attr, $post_id) {
		$search = '/youtube\.com/';
    		$replace = 'youtube-nocookie.com';

    		return preg_replace( $search, $replace, $html );
	}

    /**
     * Shortcode for a nice image placeholder
     * @author Napolux <napolux@gmail.com>
     * @usage  [placeholder width=300 height=400 secure=true]
     */
    public function placeholder_creator($attr = array()) {

        // Default values, if no values are passed
        if(!is_array($attr) || empty($attr)) {
            $secure = true;
            $width  = 200;
            $height = 200;
        } else {
            $secure     = ($attr['secure'] === 'true') ? true : false;
            $width      = (int)  $attr['width'];
            $height     = (int)  $attr['height'];
        }

        $imgUrl = '<img title="placeholder" alt="placeholder" src="' . (($secure) ? 'https://' : 'http://') . 'placehold.it/' . $width . 'x' . $height . '" />';
        return $imgUrl;
    }

}// end class

//Class instance

$wpit_utility = Wpit_Utility::getInstance();