<?php
use Psr\Http\Message\ServerRequestInterface;
use Psr\Http\Message\ResponseInterface;
use Backbeard\Dispatcher;
use Backbeard\ValidationError;

$routingFactory = function ($serviceLocator) {
    yield '/hello' => 'hello';

    $error = (yield ['POST' => '/entry/{id:[0-9]}'] => function ($id) {
        if ($this->getRequest()->getPost()['NAME'] == 'wtf') {
            return ['var1' => 'baz']; // will be render entry.phtml
        } else {
            return new ValidationError(['error message!']);
        }
    });

    yield '/entry/{id:[0-9]}' => function ($id) use ($error) {
        $message = $error ? htmlspecialchars(current($error->getMessages())) :'';
        return "Hello $id ".$message.
        '<form method="POST" action="/entry/'.$id.'">'.
            'NAME<input type="text" name="NAME">'.
        '</form>';
    };

    yield [
      'GET' => '/foo',
      'Header' => [
        'User-Agent' => function($headers){
          if (!empty($headers) && strpos(current($headers), 'Coffee') === 0) {
            return true;
          }
        }
      ]
    ] => 418; // status code "I'm a teapot"

    yield (ServerRequestInterface $request) {
		return true;
    } => function () {
    	/** @var ResponseInterface $this */
    	return $this;
    };
};

(new Dispatcher($routingFactory($serviceLocator)))->dispatch(new Request, new Response);