<?php

namespace %NAMESPACE%\Middleware;

use Psr\Http\Server\{ RequestHandlerInterface, MiddlewareInterface };
use Psr\Http\Message\{ ResponseInterface, ServerRequestInterface };
use Storage\Session;

class Authentication implements MiddlewareInterface {

    public Session $session;

    public string $sessionUserVariable = 'user';

    public ResponseInterface $loginRedirect;

    public function __construct(ResponseInterface $loginRedirect, Session $session)
    {
        $this->loginRedirect = $loginRedirect;
        $this->session = $session;
    }

    public function process(ServerRequestInterface $request, RequestHandlerInterface $handler) : ResponseInterface
    {
        $user = $this->session->get( $this->sessionUserVariable() );

        if ( ! $user ) {
            return $this->loginRedirect;
        }

        return $handler->handle($request);
    }

    public function sessionUserVariable(?string $set = null) : string
    {
        return $set !== null ? $this->sessionUserVariable = $set : $this->sessionUserVariable;
    }
}