<?php

namespace App\Tests;

use App\Content\DemoContent;
use App\Content\DocumentValidator;
use App\Content\MediaLibrary;
use App\Content\PageRepository;
use App\Content\PartialRepository;
use App\Content\SiteSettings;
use App\Infrastructure\ConnectionFactory;
use App\Kernel;
use Doctrine\DBAL\Connection;
use PHPUnit\Framework\Attributes\DataProvider;
use Symfony\Bundle\FrameworkBundle\KernelBrowser;
use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;

/**
 * The user administration, and above all the two properties that matter about it: only an
 * administrator can touch an account, and a changed password or role ends every open session of
 * that account.
 *
 * Several tests hold two sessions at once, which is the only way to show the second property. The
 * response assertions are therefore written against a named client instead of the framework's
 * "current" one - with two clients around, "current" is whichever was created last.
 */
final class UserAdminTest extends WebTestCase
{
    private const FIXTURE_PASSWORD = 'Fixture-only-password';

    private Connection $db;
    private string $path;
    private array $previous;

    protected static function getKernelClass(): string
    {
        return Kernel::class;
    }

    protected function setUp(): void
    {
        $this->path = tempnam(sys_get_temp_dir(), 'kant-users-');
        $url = 'sqlite:///'.str_replace('\\', '/', $this->path);
        $this->previous = [$_SERVER, $_ENV];
        foreach (['APP_SECRET' => 'isolated-test-secret', 'DATABASE_URL' => $url, 'SITE_ORIGIN' => 'https://cms.test', 'MEDIA_DIRECTORY' => $this->path.'-media'] as $key => $value) {
            $_SERVER[$key] = $_ENV[$key] = $value;
        }
        $this->db = ConnectionFactory::create($url);
        TestSchema::build($this->db);
        $this->db->insert('website', ['id' => 'default', 'name' => 'Test', 'default_locale' => 'de', 'theme' => '{}']);
        $this->db->insert('page', ['id' => 'p1', 'slug' => 'home', 'path' => 'home', 'type' => 'page', 'locale' => 'de', 'website_id' => 'default', 'version' => 0, 'created_at' => gmdate('Y-m-d H:i:s')]);
        $pages = new PageRepository($this->db, new DocumentValidator(), new SiteSettings($this->db, new MediaLibrary($this->db, $this->path.'-media')));
        $pages->publish('p1', $pages->saveDraft('p1', DemoContent::pages()['home'], 0), 1);
        $partials = new PartialRepository($this->db, new DocumentValidator());
        foreach (DemoContent::areas() as $kind => $area) {
            $partials->create($kind, 'default', $area['name'], $area['document']);
        }
        foreach (['admin' => 'ROLE_ADMIN', 'zweite' => 'ROLE_ADMIN', 'editor' => 'ROLE_EDITOR'] as $username => $role) {
            $this->account($username, $role);
        }
    }

    protected function tearDown(): void
    {
        parent::tearDown();
        $this->db->close();
        gc_collect_cycles();
        @unlink($this->path);
        foreach (glob($this->path.'-media/*') ?: [] as $file) {
            unlink($file);
        }
        if (is_dir($this->path.'-media')) {
            rmdir($this->path.'-media');
        }
        [$_SERVER, $_ENV] = $this->previous;
    }

    public function testOnlyAnAdministratorReachesTheAccountsAtAll(): void
    {
        self::ensureKernelShutdown();
        $anonymous = self::createClient();
        $anonymous->followRedirects(false);
        $anonymous->request('GET', '/admin/benutzer');
        self::assertSame('http://localhost/admin/login', $anonymous->getResponse()->headers->get('Location'));

        $editor = $this->login('editor');
        $editor->request('GET', '/admin/benutzer');
        self::assertSame(403, $editor->getResponse()->getStatusCode());
        // An editor does have an account screen: changing the own password is not a privilege.
        $editor->request('GET', '/admin/konto');
        self::assertSame(200, $editor->getResponse()->getStatusCode());

        foreach ([
            ['/admin/benutzer/neu', ['username' => 'geschmuggelt', 'password' => 'Ein-sehr-langes-Passwort', 'role' => 'ROLE_ADMIN']],
            ['/admin/benutzer/'.$this->id('editor').'/rolle', ['role' => 'ROLE_ADMIN']],
            ['/admin/benutzer/'.$this->id('admin').'/passwort', ['password' => 'Ein-sehr-langes-Passwort']],
            ['/admin/benutzer/'.$this->id('admin').'/loeschen', []],
        ] as [$url, $body]) {
            $editor->request('POST', $url, [...$body, '_csrf_token' => $this->token($editor, 'account')]);
            self::assertSame(403, $editor->getResponse()->getStatusCode(), $url);
        }
        self::assertSame(3, $this->accounts());
        self::assertSame('ROLE_EDITOR', $this->roleOf('editor'));
    }

    public function testAnAccountIsCreatedAndCanSignIn(): void
    {
        $client = $this->login();
        $this->submit($client, '/admin/benutzer/neu', ['username' => 'Redakteurin', 'password' => 'Ein-sehr-langes-Passwort', 'role' => 'ROLE_PUBLISHER']);
        self::assertSame('/admin/benutzer', $client->getResponse()->headers->get('Location'));

        // Stored in lower case, with the dates the list shows.
        $row = $this->db->fetchAssociative('SELECT * FROM cms_user WHERE username = ?', ['redakteurin']);
        self::assertNotFalse($row);
        self::assertSame('["ROLE_PUBLISHER"]', $row['roles']);
        self::assertNotNull($row['created_at']);
        self::assertNotNull($row['password_changed_at']);
        self::assertNull($row['last_login_at']);

        $fresh = $this->login('redakteurin', 'Ein-sehr-langes-Passwort');
        $fresh->request('GET', '/admin/benutzer');
        self::assertSame(403, $fresh->getResponse()->getStatusCode(), 'A publisher is not an administrator.');
        // The login is recorded, so nobody has to guess whether an account is still in use.
        self::assertNotNull($this->db->fetchOne('SELECT last_login_at FROM cms_user WHERE username = ?', ['redakteurin']));
    }

    /** @return iterable<string, array{array<string, string>}> */
    public static function refusedAccounts(): iterable
    {
        yield 'password too short' => [['username' => 'neu', 'password' => 'Dreizehn-Zeic', 'role' => 'ROLE_EDITOR']];
        yield 'password beyond bcrypt' => [['username' => 'neu', 'password' => str_repeat('a', 73), 'role' => 'ROLE_EDITOR']];
        yield 'password with a null byte' => [['username' => 'neu', 'password' => "Ein-langes-Pass\0wort", 'role' => 'ROLE_EDITOR']];
        yield 'username too short' => [['username' => 'ab', 'password' => 'Ein-sehr-langes-Passwort', 'role' => 'ROLE_EDITOR']];
        yield 'username with a space' => [['username' => 'neuer nutzer', 'password' => 'Ein-sehr-langes-Passwort', 'role' => 'ROLE_EDITOR']];
        yield 'username starting with a dot' => [['username' => '.neu', 'password' => 'Ein-sehr-langes-Passwort', 'role' => 'ROLE_EDITOR']];
        yield 'name already taken' => [['username' => 'editor', 'password' => 'Ein-sehr-langes-Passwort', 'role' => 'ROLE_EDITOR']];
        yield 'unknown role' => [['username' => 'neu', 'password' => 'Ein-sehr-langes-Passwort', 'role' => 'ROLE_SUPERUSER']];
    }

    #[DataProvider('refusedAccounts')]
    public function testRefusedAccountsAreNotCreated(array $body): void
    {
        $client = $this->login();
        $this->submit($client, '/admin/benutzer/neu', $body);
        self::assertSame('/admin/benutzer', $client->getResponse()->headers->get('Location'));
        self::assertSame(3, $this->accounts());
        self::assertSame('ROLE_EDITOR', $this->roleOf('editor'), 'An existing account must stay as it is.');
        self::assertCount(1, $client->followRedirect()->filter('.notice.error'));
    }

    public function testEveryWriteNeedsACsrfToken(): void
    {
        $client = $this->login();
        foreach ([
            ['/admin/benutzer/neu', ['username' => 'ohnetoken', 'password' => 'Ein-sehr-langes-Passwort', 'role' => 'ROLE_ADMIN']],
            ['/admin/benutzer/'.$this->id('editor').'/rolle', ['role' => 'ROLE_ADMIN']],
            ['/admin/benutzer/'.$this->id('editor').'/passwort', ['password' => 'Ein-sehr-langes-Passwort']],
            ['/admin/benutzer/'.$this->id('editor').'/loeschen', []],
        ] as [$url, $body]) {
            $client->request('POST', $url, [...$body, '_csrf_token' => 'wrong']);
            self::assertSame('/admin/benutzer', $client->getResponse()->headers->get('Location'), $url);
        }
        self::assertSame(3, $this->accounts());
        self::assertSame('ROLE_EDITOR', $this->roleOf('editor'));
        self::assertTrue($this->passwordWorks('editor', self::FIXTURE_PASSWORD));

        $client->request('POST', '/admin/konto/passwort', ['current' => self::FIXTURE_PASSWORD, 'password' => 'Ein-sehr-langes-Passwort', '_csrf_token' => 'wrong']);
        self::assertSame('/admin/konto', $client->getResponse()->headers->get('Location'));
        self::assertTrue($this->passwordWorks('admin', self::FIXTURE_PASSWORD));
    }

    public function testNobodyRemovesOrDemotesTheirOwnAccountSoAnAdministratorAlwaysRemains(): void
    {
        $client = $this->login();
        $me = $this->id('admin');

        $this->submit($client, '/admin/benutzer/'.$me.'/loeschen', []);
        self::assertSame(3, $this->accounts(), 'The own account must survive.');
        $this->submit($client, '/admin/benutzer/'.$me.'/rolle', ['role' => 'ROLE_EDITOR']);
        self::assertSame('ROLE_ADMIN', $this->roleOf('admin'), 'The own role must stay.');
        self::assertCount(1, $client->followRedirect()->filter('.notice.error'));

        // Another administrator can be demoted and removed, and the actor stays an administrator -
        // that is why at least one always remains.
        $this->submit($client, '/admin/benutzer/'.$this->id('zweite').'/rolle', ['role' => 'ROLE_EDITOR']);
        self::assertSame('ROLE_EDITOR', $this->roleOf('zweite'));
        $this->submit($client, '/admin/benutzer/'.$this->id('zweite').'/loeschen', []);
        self::assertSame(2, $this->accounts());
        self::assertSame('ROLE_ADMIN', $this->roleOf('admin'));
    }

    public function testAResetPasswordSignsThatAccountOutEverywhere(): void
    {
        $editor = $this->login('editor');
        $admin = $this->login();

        $this->submit($admin, '/admin/benutzer/'.$this->id('editor').'/passwort', ['password' => 'Ein-ganz-neues-Passwort']);
        self::assertSame('/admin/benutzer', $admin->getResponse()->headers->get('Location'));

        // The editor's session held the old hash, so its next request is no longer signed in.
        $editor->request('GET', '/admin');
        self::assertSame('http://localhost/admin/login', $editor->getResponse()->headers->get('Location'));
        self::assertFalse($this->passwordWorks('editor', self::FIXTURE_PASSWORD));
        self::assertTrue($this->passwordWorks('editor', 'Ein-ganz-neues-Passwort'));
        // And the administrator who made the change stays signed in.
        $admin->request('GET', '/admin/benutzer');
        self::assertSame(200, $admin->getResponse()->getStatusCode());
    }

    public function testAChangedRoleSignsThatAccountOutEverywhere(): void
    {
        $editor = $this->login('editor');
        $admin = $this->login();

        $this->submit($admin, '/admin/benutzer/'.$this->id('editor').'/rolle', ['role' => 'ROLE_PUBLISHER']);
        self::assertSame('ROLE_PUBLISHER', $this->roleOf('editor'));
        $editor->request('GET', '/admin');
        self::assertSame('http://localhost/admin/login', $editor->getResponse()->headers->get('Location'));
    }

    public function testChangingTheOwnPasswordNeedsTheCurrentOneAndKeepsThisSession(): void
    {
        $other = $this->login('editor');
        $client = $this->login('editor');

        foreach ([
            'wrong current password' => ['current' => 'Nicht-das-Passwort', 'password' => 'Ein-ganz-neues-Passwort'],
            'the same password again' => ['current' => self::FIXTURE_PASSWORD, 'password' => self::FIXTURE_PASSWORD],
            'new one too short' => ['current' => self::FIXTURE_PASSWORD, 'password' => 'Dreizehn-Zeic'],
        ] as $case => $body) {
            $this->submit($client, '/admin/konto/passwort', $body, 'account');
            self::assertSame('/admin/konto', $client->getResponse()->headers->get('Location'), $case);
            self::assertTrue($this->passwordWorks('editor', self::FIXTURE_PASSWORD), $case);
            self::assertCount(1, $client->followRedirect()->filter('.notice.error'), $case);
        }

        $this->submit($client, '/admin/konto/passwort', ['current' => self::FIXTURE_PASSWORD, 'password' => 'Ein-ganz-neues-Passwort'], 'account');
        self::assertSame('/admin/konto', $client->getResponse()->headers->get('Location'));
        self::assertFalse($this->passwordWorks('editor', self::FIXTURE_PASSWORD));
        self::assertTrue($this->passwordWorks('editor', 'Ein-ganz-neues-Passwort'));

        // This session keeps working, because it was handed the fresh account.
        $client->request('GET', '/admin/konto');
        self::assertSame(200, $client->getResponse()->getStatusCode());
        // The other session of the same account is signed out.
        $other->request('GET', '/admin');
        self::assertSame('http://localhost/admin/login', $other->getResponse()->headers->get('Location'));
    }

    public function testTheAccountScreenShowsTheOwnRoleButNoWayToChangeIt(): void
    {
        $client = $this->login('editor');
        $crawler = $client->request('GET', '/admin/konto');
        $head = $crawler->filter('.card-head')->first()->text();
        self::assertStringContainsString('editor', $head);
        self::assertStringContainsString('Redakteur', $head);
        self::assertCount(0, $crawler->filter('select[name="role"]'));
        self::assertCount(0, $crawler->filter('a[href="/admin/benutzer"]'), 'An editor is not offered the user administration.');
    }

    private function account(string $username, string $role): void
    {
        $this->db->insert('cms_user', [
            'id' => bin2hex(random_bytes(8)),
            'username' => $username,
            'password_hash' => password_hash(self::FIXTURE_PASSWORD, PASSWORD_BCRYPT, ['cost' => 4]),
            'roles' => json_encode([$role], JSON_THROW_ON_ERROR),
            'created_at' => gmdate('Y-m-d H:i:s'),
            'password_changed_at' => gmdate('Y-m-d H:i:s'),
        ]);
    }

    private function login(string $username = 'admin', string $password = self::FIXTURE_PASSWORD): KernelBrowser
    {
        // Several sessions in one test: a new client needs the kernel down before it is created,
        // and every request boots its own kernel afterwards.
        self::ensureKernelShutdown();
        $client = self::createClient();
        $client->followRedirects(false);
        $crawler = $client->request('GET', '/admin/login');
        $client->submit($crawler->selectButton('Anmelden')->form(['_username' => $username, '_password' => $password]));
        self::assertSame('http://localhost/admin', $client->getResponse()->headers->get('Location'), 'Anmeldung von '.$username);
        $client->followRedirect();
        self::assertSame(200, $client->getResponse()->getStatusCode());

        return $client;
    }

    private function submit(KernelBrowser $client, string $url, array $body, string $tokenId = 'users'): void
    {
        $client->request('POST', $url, [...$body, '_csrf_token' => $this->token($client, $tokenId)]);
    }

    /**
     * A token as the browser would carry it: read out of the form this client was served. The form
     * is addressed explicitly, because the first token on the page belongs to the logout form in
     * the shell and is issued for a different token id.
     */
    private function token(KernelBrowser $client, string $id): string
    {
        [$url, $form] = 'users' === $id
            ? ['/admin/benutzer', 'form[action="/admin/benutzer/neu"]']
            : ['/admin/konto', 'form[action="/admin/konto/passwort"]'];
        $crawler = $client->request('GET', $url);
        if (200 !== $client->getResponse()->getStatusCode()) {
            return 'no-token-for-this-account';
        }

        return (string) $crawler->filter($form.' input[name="_csrf_token"]')->first()->attr('value');
    }

    private function id(string $username): string
    {
        return (string) $this->db->fetchOne('SELECT id FROM cms_user WHERE username = ?', [$username]);
    }

    private function roleOf(string $username): string
    {
        return json_decode((string) $this->db->fetchOne('SELECT roles FROM cms_user WHERE username = ?', [$username]), true, 512, JSON_THROW_ON_ERROR)[0];
    }

    private function accounts(): int
    {
        return (int) $this->db->fetchOne('SELECT COUNT(*) FROM cms_user');
    }

    private function passwordWorks(string $username, string $password): bool
    {
        return password_verify($password, (string) $this->db->fetchOne('SELECT password_hash FROM cms_user WHERE username = ?', [$username]));
    }
}