<?php

declare(strict_types=1);

/*
 * This file is part of the TYPO3 CMS project.
 *
 * It is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License, either version 2
 * of the License, or any later version.
 *
 * For the full copyright and license information, please read the
 * LICENSE.txt file that was distributed with this source code.
 *
 * The TYPO3 project - inspiring people to share!
 */

namespace TYPO3\CMS\Frontend\Middleware;

use Psr\EventDispatcher\EventDispatcherInterface;
use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\ServerRequestInterface;
use Psr\Http\Server\MiddlewareInterface;
use Psr\Http\Server\RequestHandlerInterface;
use Psr\Log\LoggerInterface;
use Symfony\Component\RateLimiter\LimiterInterface;
use TYPO3\CMS\Core\Authentication\Event\AfterUserLoggedInEvent;
use TYPO3\CMS\Core\Context\Context;
use TYPO3\CMS\Core\RateLimiter\RateLimiterFactoryInterface;
use TYPO3\CMS\Core\RateLimiter\RequestRateLimitedException;
use TYPO3\CMS\Core\Session\UserSessionManager;
use TYPO3\CMS\Core\Utility\GeneralUtility;
use TYPO3\CMS\Core\Utility\HttpUtility;
use TYPO3\CMS\Frontend\Authentication\FrontendUserAuthentication;

/**
 * This middleware authenticates a Frontend User (fe_users).
 */
readonly class FrontendUserAuthenticator implements MiddlewareInterface
{
    public function __construct(
        protected Context $context,
        protected RateLimiterFactoryInterface $rateLimiterFactory,
        protected EventDispatcherInterface $eventDispatcher,
        protected LoggerInterface $logger,
    ) {}

    /**
     * Creates a frontend user authentication object, tries to authenticate a user and stores
     * it in the current request as attribute.
     */
    public function process(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface
    {
        $frontendUser = GeneralUtility::makeInstance(FrontendUserAuthentication::class);

        // Rate Limiting
        $rateLimiter = $this->ensureLoginRateLimit($frontendUser, $request);

        // Authenticate now
        $frontendUser->start($request);
        // no matter if we have an active user we try to fetch matching groups which can
        // be set without an user (simulation for instance!)
        $frontendUser->fetchGroupData($request);

        // Register the frontend user as aspect and within the request
        $this->context->setAspect('frontend.user', $frontendUser->createUserAspect());
        $request = $request->withAttribute('frontend.user', $frontendUser);

        if ($this->context->getAspect('frontend.user')->isLoggedIn() && $rateLimiter) {
            $rateLimiter->reset();
            $this->eventDispatcher->dispatch(new AfterUserLoggedInEvent($frontendUser, $request));
        }

        $response = $handler->handle($request);

        // Store session data for fe_users
        $frontendUser->storeSessionData();
        $response = $frontendUser->appendCookieToResponse($response, $request->getAttribute('normalizedParams'));
        // Collect garbage in Frontend requests, which aren't fully cacheable (e.g. with cookies)
        if ($response->hasHeader('Set-Cookie')) {
            $this->sessionGarbageCollection();
        }

        return $response;
    }

    /**
     * Garbage collection for fe_sessions (with a probability)
     */
    protected function sessionGarbageCollection(): void
    {
        UserSessionManager::create('FE')->collectGarbage();
    }

    protected function ensureLoginRateLimit(FrontendUserAuthentication $user, ServerRequestInterface $request): ?LimiterInterface
    {
        if (!$user->isActiveLogin($request)) {
            return null;
        }
        $loginRateLimiter = $this->rateLimiterFactory->createLoginRateLimiter($request, $user->loginType);
        $limit = $loginRateLimiter->consume();
        if (!$limit->isAccepted()) {
            $this->logger->debug('Login request has been rate limited for IP address {ipAddress}', ['ipAddress' => $request->getAttribute('normalizedParams')->getRemoteAddress()]);
            $dateformat = $GLOBALS['TYPO3_CONF_VARS']['SYS']['ddmmyy'] . ' ' . $GLOBALS['TYPO3_CONF_VARS']['SYS']['hhmm'];
            $lockedUntil = $limit->getRetryAfter()->getTimestamp() > 0
                ? ' until ' . date($dateformat, $limit->getRetryAfter()->getTimestamp()) : '';
            throw new RequestRateLimitedException(
                HttpUtility::HTTP_STATUS_403,
                'The login is locked' . $lockedUntil . ' due to too many failed login attempts from your IP address.',
                'Login Request Rate Limited',
                1616175847
            );
        }
        return $loginRateLimiter;
    }
}