<?php



class WP_AutoUpdate {



	/**



	 * The plugin current version



	 * @var string



	 */



	private $current_version;







	/**



	 * The plugin remote update path



	 * @var string



	 */



	private $update_path;







	/**



	 * Plugin Slug (plugin_directory/plugin_file.php)



	 * @var string



	 */



	private $plugin_slug;







	/**



	 * Plugin name (plugin_file)



	 * @var string



	 */



	private $slug;







	/**



	 * License User



	 * @var string



	 */



	private $license_user;







	/**



	 * License Key



	 * @var string



	 */



	private $license_key;







	/**



	 * Initialize a new instance of the WordPress Auto-Update class



	 * @param string $current_version



	 * @param string $update_path



	 * @param string $plugin_slug



	 */



	public function __construct( $current_version, $update_path, $plugin_slug, $license_user = '', $license_key = '' )



	{



		// Set the class public variables



		$this->current_version = $current_version;



		$this->update_path = $update_path;







		// Set the License



		$this->license_user = $license_user;



		$this->license_key = $license_key;







		// Set the Plugin Slug



		$this->plugin_slug = $plugin_slug;



		list ($t1, $t2) = explode( '/', $plugin_slug );



		$this->slug = str_replace( '.php', '', $t2 );







		// define the alternative API for updating checking



		add_filter( 'pre_set_site_transient_update_plugins', array( &$this, 'check_update' ) );







		// Define the alternative response for information checking



		add_filter( 'plugins_api', array( &$this, 'check_info' ), 10, 3 );



	}







	/**



	 * Add our self-hosted autoupdate plugin to the filter transient



	 *



	 * @param $transient



	 * @return object $ transient



	 */



	public function check_update( $transient )



	{



		if ( empty( $transient->checked ) ) {



			return $transient;



		}







		// Get the remote version



		$remote_version = $this->getRemote('version');







		// If a newer version is available, add the update



		if ( version_compare( $this->current_version, $remote_version->new_version, '<' ) ) {



			$obj = new stdClass();



			$obj->slug = $this->slug;



			$obj->new_version = $remote_version->new_version;



			$obj->url = $remote_version->url;



			$obj->plugin = $this->plugin_slug;



			$obj->package = $remote_version->package;



			$obj->tested = $remote_version->tested;



			$transient->response[$this->plugin_slug] = $obj;



		}



		return $transient;



	}







	/**



	 * Add our self-hosted description to the filter



	 *



	 * @param boolean $false



	 * @param array $action



	 * @param object $arg



	 * @return bool|object



	 */



	public function check_info($obj, $action, $arg)



	{



		if (($action=='query_plugins' || $action=='plugin_information') &&



		    isset($arg->slug) && $arg->slug === $this->slug) {



			return $this->getRemote('info');



		}







		return $obj;



	}







	/**



	 * Return the remote version



	 *



	 * @return string $remote_version



	 */



	public function getRemote($action = '')



	{



		$params = array(



			'body' => array(



				'action'       => $action,



				'license_user' => $this->license_user,



				'license_key'  => $this->license_key,



			),



		);







		// Make the POST request



		$request = wp_remote_post($this->update_path, $params );







		// Check if response is valid



		if ( !is_wp_error( $request ) || wp_remote_retrieve_response_code( $request ) === 200 ) {



			return @unserialize( $request['body'] );



		}







		return false;



	}



}



