<?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\Backend\Controller;

use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\ServerRequestInterface;
use TYPO3\CMS\Backend\Attribute\AsController;
use TYPO3\CMS\Backend\Authentication\BackendLocker;
use TYPO3\CMS\Core\Authentication\BackendUserAuthentication;
use TYPO3\CMS\Core\Authentication\LoginType;
use TYPO3\CMS\Core\FormProtection\BackendFormProtection;
use TYPO3\CMS\Core\FormProtection\FormProtectionFactory;
use TYPO3\CMS\Core\Http\JsonResponse;
use TYPO3\CMS\Core\Session\UserSessionManager;

/**
 * This is the ajax handler for backend login after timeout.
 * @internal This class is a specific Backend controller implementation and is not considered part of the Public TYPO3 API.
 */
#[AsController]
readonly class AjaxLoginController
{
    public function __construct(
        protected FormProtectionFactory $formProtectionFactory,
        protected BackendLocker $lockService,
    ) {}

    /**
     * Handles the actual login process, more specifically it defines the response.
     * The login details were sent in as part of the ajax request and automatically logged in
     * the user inside the BackendUserAuthenticator middleware. If that was successful, we have
     * a BE user and reset the timer and hide the login window.
     * If it was unsuccessful, we display that and show the login box again.
     */
    public function loginAction(ServerRequestInterface $request): ResponseInterface
    {
        if ($this->isAuthorizedBackendSession()) {
            $result = ['success' => true];
            if ($this->hasLoginBeenProcessed($request)) {
                /** @var BackendFormProtection $formProtection */
                $formProtection = $this->formProtectionFactory->createFromRequest($request);
                $formProtection->setSessionTokenFromRegistry();
                $formProtection->persistSessionToken();
            }
        } else {
            $result = ['success' => false];
        }
        return new JsonResponse(['login' => $result]);
    }

    /**
     * Logs out the current BE user
     */
    public function logoutAction(ServerRequestInterface $request): ResponseInterface
    {
        $backendUser = $this->getBackendUser();
        $backendUser->logoff();
        return new JsonResponse([
            'logout' => [
                'success' => !isset($backendUser->user['uid']),
            ],
        ]);
    }

    public function preflightAction(ServerRequestInterface $request): ResponseInterface
    {
        $headers = $request->getHeaders();
        return new JsonResponse([
            'capabilities' => [
                'cookie' => !empty($request->getCookieParams()),
                // using legacy `Referer` (sic!) header name
                'referrer' => array_filter($headers['referer'] ?? []) !== [],
            ],
        ]);
    }

    /**
     * Handles the actual session refresh, more specifically it defines the response.
     * The session refresh has been performed inside the BackendUserAuthenticator middleware.
     * If that was successful, we have a BE user and report that information as response.
     */
    public function refreshAction(ServerRequestInterface $request): ResponseInterface
    {
        $backendUser = $this->getBackendUser();
        return new JsonResponse([
            'refresh' => [
                'success' => isset($backendUser->user['uid']),
            ],
        ]);
    }

    /**
     * Checks if the user session is expired yet
     */
    public function isTimedOutAction(ServerRequestInterface $request): ResponseInterface
    {
        $session = [
            'timed_out' => false,
            'will_time_out' => false,
            'locked' => false,
        ];
        $backendUser = $this->getBackendUser();
        if ($this->lockService->isLocked()) {
            $session['locked'] = true;
        } elseif (!isset($backendUser->user['uid'])) {
            $session['timed_out'] = true;
        } else {
            $sessionManager = UserSessionManager::create('BE');
            // If 120 seconds from now is later than the session timeout, we need to show the refresh dialog.
            // 120 is somewhat arbitrary to allow for a little room during the countdown and load times, etc.
            $session['will_time_out'] = $sessionManager->willExpire($backendUser->getSession(), 120);
        }
        return new JsonResponse(['login' => $session]);
    }

    /**
     * Checks if a user is logged in and the session is active.
     *
     * @return bool
     */
    protected function isAuthorizedBackendSession()
    {
        $backendUser = $this->getBackendUser();
        if ($backendUser === null) {
            return false;
        }
        return isset($backendUser->user['uid']);
    }

    /**
     * Check whether the user was already authorized or not
     */
    protected function hasLoginBeenProcessed(ServerRequestInterface $request): bool
    {
        $loginFormData = $this->getBackendUser()->getLoginFormData($request);
        return LoginType::tryFrom($loginFormData['status'] ?? '') === LoginType::LOGIN && !empty($loginFormData['uname']) && !empty($loginFormData['uident']);
    }

    protected function getBackendUser(): ?BackendUserAuthentication
    {
        return $GLOBALS['BE_USER'] ?? null;
    }
}