<?php
//declare the fully qualified class names that we use at the beginning of the file
//we'll add more as we progress
use Zend\Stratigility\MiddlewarePipe;
use Psr\Http\Message\ServerRequestInterface;
use Psr\Http\Message\ResponseInterface;
use Zend\Diactoros\Response\SapiEmitter;

//change the current directory to the parent of /public
chdir(dirname(__DIR__));

//we load the file by using its relative path(to the current dir we have set above)
require 'vendor/autoload.php';

// generate the request and response
$request = ServerRequestFactory::fromGlobals($_SERVER, $_GET, $_POST, $_COOKIE, $_FILES);
$response = new Response();

// initializing Zend\Stratigility\MidlewarePipe application
$application = new MiddlewarePipe();

$application->pipe('/',
    function(ServerRequestInterface $request, ResponseInterface $response, callable $next = null)
    {
        //check the uri path to see if we requested the home page or not
        if(! in_array($request->getUri()->getPath(), ['', '/'])) {
            //if path not empty, we have nothing to do here, call next middleware to display the requested page
            return $next($request, $response);
        }

        //display the html home page, we use the zend-diactoros HtmlResponse
        //HtmlResponse accepts the html string as parameter. It sets code 200 by default and add the Content-Type header text/html
        return new HtmlResponse("<h1>Home page</h1>");
    }
);

$application->pipe('/about',
    function(ServerRequestInterface $request, ResponseInterface $response, callable $next = null) {
        //directly return a response
        return new HtmlResponse("<h1>About Us</h1>");
    }
);

//run the application with the initial request/response object created earlier
$response = $application($request, $response);

//we need to send the response to the browser, we use diactoros emitter class that do the conversion for us
$emitter = new SapiEmitter();
$emitter->emit($response);