<?php

namespace Demo\EventListener;

use Symfony\Component\HttpKernel\KernelEvents;
use Symfony\Component\HttpKernel\Event\GetResponseForControllerResultEvent;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\HttpFoundation\Response;

class TemplateRenderingListener implements EventSubscriberInterface
{
    protected $app;

    public function __construct(Application $app)
    {
        $this->app = $app;
    }

    public function onKernelView(GetResponseForControllerResultEvent $event)
    {
        $response = $event->getControllerResult();
        if (!is_array($response)) {
            return;
        }

        $request = $event->getRequest();
        $routeName = $request->attributes->get('_route');
        if (!$route = $this->app['routes']->get($routeName)) {
            return;
        }

        if (!$template = $route->getOption('_template')) {
            return;
        }

        $output = $this->app['twig']->render($template, $response);
        $event->setResponse(new Response($output));
    }

    public static function getSubscribedEvents()
    {
        return array(
            KernelEvents::VIEW => array('onKernelView', -10),
        );
    }
}