<?php

// {{{ License
// This file is part of GNU social - https://www.gnu.org/software/social
//
// GNU social is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// GNU social is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with GNU social.  If not, see <http://www.gnu.org/licenses/>.
// }}}

namespace App\Security;

use App\Core\DB\DB;
use function App\Core\I18n\_m;
use App\Core\Log;
use App\Entity\User;
use App\Util\Nickname;
use Doctrine\ORM\EntityManagerInterface;
use Symfony\Component\HttpFoundation\RedirectResponse;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\Routing\Generator\UrlGeneratorInterface;
use Symfony\Component\Security\Core\Authentication\Token\TokenInterface;
use Symfony\Component\Security\Core\Exception\CustomUserMessageAuthenticationException;
use Symfony\Component\Security\Core\Exception\InvalidCsrfTokenException;
use Symfony\Component\Security\Core\Security;
use Symfony\Component\Security\Core\User\UserInterface;
use Symfony\Component\Security\Core\User\UserProviderInterface;
use Symfony\Component\Security\Csrf\CsrfToken;
use Symfony\Component\Security\Csrf\CsrfTokenManagerInterface;
use Symfony\Component\Security\Guard\Authenticator\AbstractFormLoginAuthenticator;
use Symfony\Component\Security\Http\Util\TargetPathTrait;

/**
 * User authenticator
 *
 * @category  Authentication
 * @package   GNUsocial
 *
 * @author    Hugo Sales <hugo@fc.up.pt>
 * @copyright 2020 Free Software Foundation, Inc http://www.fsf.org
 * @license   https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
 */
class Authenticator extends AbstractFormLoginAuthenticator
{
    use TargetPathTrait;

    public const LOGIN_ROUTE = 'login';

    private $entityManager;
    private $urlGenerator;
    private $csrfTokenManager;

    public function __construct(EntityManagerInterface $entityManager, UrlGeneratorInterface $urlGenerator, CsrfTokenManagerInterface $csrfTokenManager)
    {
        $this->entityManager    = $entityManager;
        $this->urlGenerator     = $urlGenerator;
        $this->csrfTokenManager = $csrfTokenManager;
    }

    public function supports(Request $request)
    {
        return self::LOGIN_ROUTE === $request->attributes->get('_route') && $request->isMethod('POST');
    }

    public function getCredentials(Request $request)
    {
        $credentials = [
            'nickname'   => $request->request->get('nickname'),
            'password'   => $request->request->get('password'),
            'csrf_token' => $request->request->get('_csrf_token'),
        ];
        $request->getSession()->set(
            Security::LAST_USERNAME,
            $credentials['nickname']
        );

        return $credentials;
    }

    public function getUser($credentials, UserProviderInterface $userProvider)
    {
        $token = new CsrfToken('authenticate', $credentials['csrf_token']);
        if (!$this->csrfTokenManager->isTokenValid($token)) {
            throw new InvalidCsrfTokenException();
        }

        $nick = Nickname::normalize($credentials['nickname']);
        $user = DB::findOneBy('local_user', ['or' => ['nickname' => $nick, 'outgoing_email' => $nick]]);

        if (!$user) {
            throw new CustomUserMessageAuthenticationException(
                _m('Either \'{nickname}\' doesn\'t match any registered nickname or email, or the supplied password is incorrect.', ['{nickname}' => $credentials['nickname']]));
        }

        return $user;
    }

    public function checkCredentials($credentials, UserInterface $user)
    {
        $password = $user->getPassword();
        Log::error(print_r($user, true));
        // crypt understands what the salt part of $user->password is
        if ($password === crypt($credentials['password'], $user->password)) {
            $this->changePassword($user->nickname, null, $password);
            return $user;
        }

        // If we check StatusNet hash, for backwards compatibility and migration
        if ($this->statusnet && $user->password === md5($password . $user->id)) {
            // and update password hash entry to crypt() compatible
            if ($this->overwrite) {
                $this->changePassword($user->nickname, null, $password);
            }
            return $user;
        }

        // Timing safe password verification on supported PHP versions
        if (password_verify($password, $user->password)) {
            return $user;
        }

        return false;
    }

    public function onAuthenticationSuccess(Request $request, TokenInterface $token, $providerKey)
    {
        if ($targetPath = $this->getTargetPath($request->getSession(), $providerKey)) {
            return new RedirectResponse($targetPath);
        }

        // For example : return new RedirectResponse($this->urlGenerator->generate('some_route'));
        throw new \Exception('TODO: provide a valid redirect inside ' . __FILE__);
    }

    protected function getLoginUrl()
    {
        return $this->urlGenerator->generate(self::LOGIN_ROUTE);
    }
}