Load Facebook SDK

I'm trying to load Facebook SDL into my project but at the moment with no success

here is my bootstrap dispatcher:

$di->set('Facebook', function() use ($config) { return new Facebook(array( 'appId' => $config->facebook->appId, 'secret' => $config->facebook->secret, 'fileUpload' => $config->facebook->fileUpload, // optional 'allowSignedRequest' => $config->facebook->allowSignedRequest, )); });

the loader looks like this(in code is before dispatcher):

$loader->registerDirs( array( DIR . $config->application->controllersDir, DIR . $config->application->pluginsDir, DIR . '/app/library', DIR . $config->application->modelsDir, DIR . '/app/facebook', ) )->register();

where facebook files were put in /app/facebook, /app/library, /app/library/facebook. Itried multiple ways of including the files.

I called the facebook class like this: $user = $this->Facebook->getUser(); in IndexController and error which i received is: Fatal error: Class 'Facebook' not found in /mylongpath/public/index.php on line 142

I assume the problem is the loader by not sure what and why. Please help me with this situation.

The rest of project is "INVO" tutorial.

edited May '14

How about: