<?php

namespace App\Controller;

use App\Content\CustomCode;
use App\Content\DemoContent;
use App\Content\DocumentValidator;
use App\Content\MenuRepository;
use App\Content\PageRepository;
use App\Content\PartialRepository;
use App\Content\PostLayouts;
use App\Content\PostRepository;
use App\Content\RedirectRepository;
use App\Content\StyleCompiler;
use App\Content\StyleSchema;
use App\Content\Theme;
use App\Domain\InvalidDocument;
use App\Domain\InvalidPage;
use App\Domain\StaleWrite;
use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
use Symfony\Component\HttpFoundation\JsonResponse;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\RequestStack;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\Routing\Attribute\Route;
use Symfony\Component\Security\Csrf\CsrfTokenManagerInterface;

#[Route('/%kant.admin_path%')]
final class EditorController extends AbstractController
{
    public function __construct(private PageRepository $pages, private DocumentValidator $validator, private MenuRepository $menus, private PostRepository $posts, private Theme $theme, private StyleCompiler $styles, private RedirectRepository $redirects, private PartialRepository $partials, private CustomCode $code, private CsrfTokenManagerInterface $csrf, private RequestStack $requests)
    {
    }

    #[Route('', name: 'admin_pages', methods: ['GET'])]
    #[Route('/posts', name: 'admin_posts', methods: ['GET'])]
    public function index(Request $request): Response
    {
        $type = 'admin_posts' === $request->attributes->get('_route') ? 'post' : 'page';
        $query = mb_substr(trim($request->query->getString('q')), 0, 160);
        $status = $request->query->getString('status', 'all');
        $status = in_array($status, ['all', 'draft', 'published', 'changed', 'trash'], true) ? $status : 'all';
        $result = $this->pages->editorPage($type, $request->query->getInt('seite', 1), $request->query->getInt('limit', 20), $query, $status);
        $pages = $result['items'];
        $parentChoices = [];
        foreach ($pages as &$page) {
            $page['document'] = json_decode($page['document'] ?? '{}', true, 512, JSON_THROW_ON_ERROR);
            $page['title'] = $page['document']['title'] ?? $page['slug'];
            $page['depth'] = substr_count((string) $page['path'], '/');
            $page['terms'] = 'post' === $page['type'] ? $this->posts->namesFor($page['id']) : ['category' => '', 'tag' => ''];
            if ($page['parent_id'] && !isset($parentChoices[$page['parent_id']])) {
                $parentChoices[$page['parent_id']] = $this->pages->choices(id: $page['parent_id'])[0] ?? null;
            }
        }
        unset($page);

        $view = [
            'pages' => 'trash' === $status ? [] : $pages,
            'trash' => 'trash' === $status ? array_map(static fn (array $p): array => [...$p, 'deletedAt' => $p['deleted_at']], $pages) : [],
            'parentChoices' => $parentChoices, 'postLayouts' => PostLayouts::all(),
            'contentType' => $type, 'result' => $result, 'query' => $query, 'status' => $status,
            'listRoute' => 'post' === $type ? 'admin_posts' : 'admin_pages',
            'areaChoices' => ['header' => $this->partials->choices('header'), 'footer' => $this->partials->choices('footer')],
        ];
        if ($request->isXmlHttpRequest()) {
            return $this->json([
                'html' => $this->renderView('admin/content-results.html.twig', $view),
                'total' => $result['total'],
                'parameters' => ['q' => $query, 'status' => $status, 'limit' => $result['limit'], 'seite' => $result['page']],
            ]);
        }

        return $this->render('admin/pages.html.twig', $view);
    }

    #[Route('/api/content-choices', name: 'admin_content_choices', methods: ['GET'])]
    public function contentChoices(Request $request): JsonResponse
    {
        $this->denyAccessUnlessGranted('ROLE_EDITOR');

        return $this->json(['items' => $this->pages->choices(
            mb_substr($request->query->getString('q'), 0, 160),
            $request->query->getString('type'), $request->query->getBoolean('parents'),
        )]);
    }

    #[Route('/pages', name: 'admin_create', methods: ['POST'])]
    public function create(Request $request): Response
    {
        $this->denyAccessUnlessGranted('ROLE_EDITOR');
        if (!$this->isCsrfTokenValid('pages', $request->request->getString('_csrf_token'))) {
            return $this->back('Deine Sitzung ist abgelaufen. Bitte melde dich erneut an.');
        }
        $title = trim($request->request->getString('title'));
        if ('' === $title || mb_strlen($title) > 160) {
            return $this->back('Bitte gib einen Titel mit höchstens 160 Zeichen an.');
        }
        $type = $request->request->getString('type', 'page');
        $parentId = $request->request->getString('parent_id') ?: null;
        $slug = trim($request->request->getString('slug')) ?: $this->slugify($title);
        try {
            // Ein Beitrag beginnt mit einem Aufbau, eine Seite leer: bei einer Seite weiß
            // niemand vorher, was daraus wird, bei einem Beitrag fast immer.
            $layout = $request->request->getString('layout', PostLayouts::DEFAULT);
            $document = 'post' === $type && PostLayouts::exists($layout)
                ? PostLayouts::document($layout, $title)
                : DemoContent::starter($title, $type);
            $id = $this->pages->createPage($slug, $parentId, $type, $document);
        } catch (InvalidPage|InvalidDocument $e) {
            return $this->back($e->getMessage());
        }

        $this->addFlash('success', sprintf('„%s“ wurde als Entwurf angelegt. Die Seite ist erst nach dem Veröffentlichen öffentlich.', $title));

        return $this->redirectToRoute('admin_editor', ['id' => $id]);
    }

    /** The editor reads the style vocabulary and the palette from here, so both stay in one place. */
    #[Route('/api/design', name: 'admin_design', methods: ['GET'])]
    public function design(): JsonResponse
    {
        $theme = $this->theme->load();

        return $this->json([
            'properties' => StyleSchema::properties(),
            'devices' => StyleSchema::DEVICES,
            'sides' => StyleSchema::sides(),
            'corners' => StyleSchema::corners(),
            'hoverable' => StyleSchema::hoverable(),
            'colors' => $theme['colors'],
            'fonts' => $theme['fonts'],
            'presets' => $theme['presets'],
            'base' => $theme['base'],
            'buttons' => $theme['buttons'],
            'buttonOptions' => \App\Content\ButtonDesign::OPTIONS,
            'buttonPresets' => \App\Content\ButtonDesign::PRESETS,
            'csrfToken' => $this->csrf->getToken('editor')->getValue(),
        ]);
    }

    /** Saves or removes a reusable style, so a look can be applied to other blocks and pages. */
    #[Route('/api/style-presets', name: 'admin_style_preset', methods: ['POST'])]
    public function stylePreset(Request $request): JsonResponse
    {
        $this->denyAccessUnlessGranted('ROLE_EDITOR');
        if (!$this->isCsrfTokenValid('editor', $request->headers->get('X-CSRF-Token'))) {
            return $this->json(['error' => 'Deine Sitzung ist abgelaufen. Bitte melde dich erneut an.'], 403);
        }
        try {
            $body = json_decode($request->getContent(), true, 16, JSON_THROW_ON_ERROR);
            $style = $body['style'] ?? null;
            $this->theme->savePreset((string) ($body['name'] ?? ''), is_array($style) ? $style : null, $this->styles);
        } catch (InvalidPage|InvalidDocument $e) {
            return $this->json(['error' => $e->getMessage()], 422);
        } catch (\JsonException) {
            return $this->json(['error' => 'Die Anfrage ist unvollständig.'], 422);
        }

        return $this->json(['presets' => $this->theme->load()['presets']]);
    }

    #[Route('/pages/{id}/meta', name: 'admin_post_meta', methods: ['POST'])]
    public function metadata(Request $request, string $id): Response
    {
        $this->denyAccessUnlessGranted('ROLE_EDITOR');
        if (!$this->isCsrfTokenValid('pages', $request->request->getString('_csrf_token'))) {
            return $this->back('Deine Sitzung ist abgelaufen. Bitte melde dich erneut an.');
        }
        $terms = static function (string $raw): array {
            $names = array_filter(array_map(trim(...), explode(',', $raw)), static fn (string $n): bool => '' !== $n);

            return array_values(array_unique($names));
        };
        try {
            $this->posts->saveMetadata(
                $id,
                [
                    'excerpt' => $request->request->getString('excerpt'),
                    'author' => $request->request->getString('author'),
                    'publishedAt' => $request->request->getString('publishedAt'),
                    'featuredMediaId' => $request->request->getString('featuredMediaId'),
                    'ogMediaId' => $request->request->getString('ogMediaId'),
                    'seoTitle' => $request->request->getString('seoTitle'),
                    'robots' => $request->request->getString('robots', 'index'),
                ],
                $terms($request->request->getString('categories')),
                $terms($request->request->getString('tags')),
                $request->request->getInt('expectedVersion', -1),
            );
        } catch (InvalidPage|StaleWrite $e) {
            return $this->back($e->getMessage());
        }

        return $this->back('Die Beitragsdaten wurden gespeichert.', 'success');
    }

    /** Which header and footer this page uses, including none at all. */
    #[Route('/pages/{id}/bereiche', name: 'admin_page_areas', methods: ['POST'])]
    public function areas(Request $request, string $id): Response
    {
        $this->denyAccessUnlessGranted('ROLE_EDITOR');
        if (!$this->isCsrfTokenValid('pages', $request->request->getString('_csrf_token'))) {
            return $this->back('Deine Sitzung ist abgelaufen. Bitte melde dich erneut an.');
        }
        // An empty field means "the standard area"; that is stored as null, not as an address.
        $choice = static fn (string $value): ?string => '' === $value ? null : $value;
        try {
            $this->pages->saveAreas(
                $id,
                $choice($request->request->getString('headerArea')),
                $choice($request->request->getString('footerArea')),
                $request->request->getInt('expectedVersion', -1),
            );
        } catch (InvalidPage|StaleWrite $e) {
            return $this->back($e->getMessage());
        }

        return $this->back('Kopf- und Fußbereich dieser Seite wurden gespeichert.', 'success');
    }

    #[Route('/pages/{id}/move', name: 'admin_move', methods: ['POST'])]
    public function move(Request $request, string $id): Response
    {
        $this->denyAccessUnlessGranted('ROLE_EDITOR');
        if (!$this->isCsrfTokenValid('pages', $request->request->getString('_csrf_token'))) {
            return $this->back('Deine Sitzung ist abgelaufen. Bitte melde dich erneut an.');
        }
        try {
            $moved = $this->pages->movePage(
                $id,
                $request->request->getString('slug'),
                $request->request->getString('parent_id') ?: null,
                $request->request->getInt('expectedVersion', -1),
                $this->redirects,
            );
        } catch (InvalidPage|StaleWrite $e) {
            return $this->back($e->getMessage());
        }

        return $this->back(0 === $moved
            ? 'Die Adresse ist unverändert.'
            : sprintf('%d Adresse(n) geändert. Von den alten Adressen wird dauerhaft weitergeleitet.', $moved), 'success');
    }

    #[Route('/pages/{id}/schedule', name: 'admin_schedule', methods: ['POST'])]
    public function schedule(Request $request, string $id): Response
    {
        $this->denyAccessUnlessGranted('ROLE_PUBLISHER');
        if (!$this->isCsrfTokenValid('pages', $request->request->getString('_csrf_token'))) {
            return $this->back('Deine Sitzung ist abgelaufen. Bitte melde dich erneut an.');
        }
        try {
            $this->pages->schedule($id, $request->request->getString('publishAt'), $request->request->getInt('expectedVersion', -1));
        } catch (InvalidPage|StaleWrite $e) {
            return $this->back($e->getMessage());
        }

        return $this->back('' === trim($request->request->getString('publishAt'))
            ? 'Die geplante Veröffentlichung wurde entfernt.'
            : 'Die Veröffentlichung ist geplant. Sie erfolgt beim ersten Aufruf der Website nach diesem Zeitpunkt – siehe „Aufgaben“.', 'success');
    }

    #[Route('/pages/{id}/restore', name: 'admin_restore_page', methods: ['POST'])]
    public function restorePage(Request $request, string $id): Response
    {
        $this->denyAccessUnlessGranted('ROLE_EDITOR');
        if (!$this->isCsrfTokenValid('pages', $request->request->getString('_csrf_token'))) {
            return $this->back('Deine Sitzung ist abgelaufen. Bitte melde dich erneut an.');
        }
        try {
            $this->pages->restorePage($id);
        } catch (InvalidPage $e) {
            return $this->back($e->getMessage());
        }

        return $this->back('Die Seite ist zurück. Sie ist erst nach dem Veröffentlichen wieder öffentlich.', 'success');
    }

    #[Route('/pages/{id}/revisions/{revision}', name: 'admin_restore_revision', requirements: ['revision' => '[a-f0-9]{32}'], methods: ['POST'])]
    public function restoreRevision(Request $request, string $id, string $revision): Response
    {
        $this->denyAccessUnlessGranted('ROLE_EDITOR');
        if (!$this->isCsrfTokenValid('pages', $request->request->getString('_csrf_token'))) {
            return $this->back('Deine Sitzung ist abgelaufen. Bitte melde dich erneut an.');
        }
        try {
            $this->pages->restoreRevision($id, $revision, $request->request->getInt('expectedVersion', -1));
        } catch (InvalidPage|StaleWrite $e) {
            return $this->back($e->getMessage());
        }

        return $this->back('Die Fassung ist als Entwurf zurück. Der bisherige Stand bleibt als eigene Fassung erhalten.', 'success');
    }

    #[Route('/pages/{id}/revisions', name: 'admin_revisions', methods: ['GET'])]
    public function revisions(Request $request, string $id): Response
    {
        $page = $this->page($id);

        return $this->render('admin/revisions.html.twig', [
            'page' => $page,
            'title' => $page['document']['title'] ?? $page['path'],
            'revisions' => $this->pages->revisions($id, $request->query->getInt('seite', 1)),
        ]);
    }

    #[Route('/pages/{id}/trash', name: 'admin_trash', methods: ['POST'])]
    public function trash(Request $request, string $id): Response
    {
        $this->denyAccessUnlessGranted('ROLE_EDITOR');
        if (!$this->isCsrfTokenValid('pages', $request->request->getString('_csrf_token'))) {
            return $this->back('Deine Sitzung ist abgelaufen. Bitte melde dich erneut an.');
        }
        try {
            $count = $this->pages->trashPage($id, $request->request->getInt('expectedVersion', -1));
        } catch (InvalidPage|StaleWrite $e) {
            return $this->back($e->getMessage());
        }

        return $this->back(sprintf('%d Seite(n) in den Papierkorb gelegt. Öffentlich nicht mehr erreichbar, aber wiederherstellbar.', $count), 'success');
    }

    #[Route('/pages/{id}/delete', name: 'admin_delete', methods: ['POST'])]
    public function delete(Request $request, string $id): Response
    {
        // The final removal deletes every revision, so it stays with the administrator role.
        // Everyone with the editor role uses the bin instead.
        $this->denyAccessUnlessGranted('ROLE_ADMIN');
        if (!$this->isCsrfTokenValid('pages', $request->request->getString('_csrf_token'))) {
            return $this->back('Deine Sitzung ist abgelaufen. Bitte melde dich erneut an.');
        }
        try {
            $this->pages->deletePage($id, $request->request->getInt('expectedVersion', -1));
        } catch (InvalidPage $e) {
            return $this->back($e->getMessage());
        } catch (StaleWrite $e) {
            return $this->back($e->getMessage());
        }

        return $this->back('Die Seite wurde mit allen Ständen gelöscht.', 'success');
    }

    /** Derives an address from the title so the editor does not have to invent one. */
    private function slugify(string $title): string
    {
        $slug = strtr(mb_strtolower($title, 'UTF-8'), ['ä' => 'ae', 'ö' => 'oe', 'ü' => 'ue', 'ß' => 'ss']);
        $slug = preg_replace('/[^a-z0-9]+/', '-', $slug) ?? '';

        return substr(trim($slug, '-'), 0, 80);
    }

    private function back(string $message, string $type = 'error'): Response
    {
        $this->addFlash($type, $message);
        $request = $this->requests->getCurrentRequest();
        $post = 'post' === $request?->request->getString('_list_type', $request?->request->getString('type', 'page'));

        if (!$request?->request->has('_list_type')) {
            return $this->redirectToRoute($post ? 'admin_posts' : 'admin_pages');
        }

        $params = [
            'q' => $request?->request->getString('_list_query', ''),
            'status' => $request?->request->getString('_list_status', 'all'),
            'seite' => $request?->request->getInt('_list_page', 1),
            'limit' => $request?->request->getInt('_list_limit', 20),
        ];
        foreach (['q' => '', 'status' => 'all', 'seite' => 1, 'limit' => 20] as $key => $default) {
            if ($params[$key] === $default) {
                unset($params[$key]);
            }
        }

        return $this->redirectToRoute($post ? 'admin_posts' : 'admin_pages', $params);
    }

    #[Route('/pages/{id}', name: 'admin_editor', methods: ['GET'])]
    public function editor(string $id): Response
    {
        $page = $this->page($id);

        return $this->render('admin/editor.html.twig', ['page' => $page]);
    }

    #[Route('/api/pages/{id}', name: 'admin_document', methods: ['GET'])]
    public function document(string $id): JsonResponse
    {
        return $this->json($this->payload($this->page($id)));
    }

    #[Route('/api/pages/{id}/draft', name: 'admin_save', methods: ['POST'])]
    #[Route('/api/pages/{id}/publish', name: 'admin_publish', methods: ['POST'])]
    #[Route('/api/pages/{id}/preview', name: 'admin_preview', methods: ['POST'])]
    public function write(Request $request, string $id): Response
    {
        $this->denyAccessUnlessGranted('ROLE_EDITOR');
        if (!$this->isCsrfTokenValid('editor', $request->headers->get('X-CSRF-Token'))) {
            return $this->json(['error' => 'Deine Sitzung ist abgelaufen. Bitte melde dich erneut an.'], 403);
        }
        if (strlen($request->getContent()) > 270000) {
            return $this->json(['error' => 'Die Seite ist zu groß (maximal 256 KiB Inhalt).'], 413);
        }
        $page = $this->page($id);
        try {
            $body = json_decode($request->getContent(), true, 64, JSON_THROW_ON_ERROR);
            if (!is_array($body)) {
                throw new \InvalidArgumentException();
            }
            $route = $request->attributes->get('_route');
            if ('admin_preview' === $route) {
                $document = $body['document'] ?? null;
                if (!is_array($document)) {
                    throw new \InvalidArgumentException();
                }
                $this->validator->validate($document);

                $theme = $this->theme->load();
                $areas = [];
                foreach (['header', 'footer'] as $kind) {
                    $area = $this->partials->findByKind($kind);
                    if (null !== $area) {
                        $areas[$kind] = $area['document'];
                    }
                }
                $sections = [];
                foreach ($this->partials->referencedSlugs($document) as $slug) {
                    $section = $this->partials->resolveSection($slug);
                    if (null !== $section) {
                        $sections[$slug] = $section['document'];
                    }
                }
                $navigation = [];
                foreach ($this->menus->all() as $slot => $menu) {
                    $navigation[$slot] = $this->menus->resolve($menu['items'], (string) $page['path']);
                }

                return $this->render('page.html.twig', ['page' => [...$page, 'document' => $document], 'canonical' => '', 'editing' => true, 'navigation' => $navigation, 'areas' => $areas, 'sections' => $sections, 'needsTabs' => false, 'pageStyles' => $this->theme->css($theme).$this->styles->compileDocument($document), 'googleFonts' => $this->theme->googleFontsUrl($theme)]);
            }
            if (!isset($body['expectedVersion']) || !is_int($body['expectedVersion']) || $body['expectedVersion'] < 0) {
                throw new \InvalidArgumentException();
            }
            if ('admin_publish' === $route) {
                $this->denyAccessUnlessGranted('ROLE_PUBLISHER');
                // The user must publish the exact draft they reviewed, never whichever draft happens to be latest.
                if (($body['revisionId'] ?? null) !== $page['draft_revision_id']) {
                    throw new StaleWrite();
                }
                $this->pages->publish($id, $body['revisionId'], $body['expectedVersion']);
                $page['published_revision_id'] = $body['revisionId'];
            } else {
                if (!is_array($body['document'] ?? null)) {
                    throw new \InvalidArgumentException();
                }
                if (!$this->isGranted('ROLE_ADMIN')) {
                    $this->code->assertScriptsUnchanged($body['document'], $page['document']);
                }
                $page['draft_revision_id'] = $this->pages->saveDraft($id, $body['document'], $body['expectedVersion']);
                $page['document'] = $body['document'];
            }
            $page['version'] = $body['expectedVersion'] + 1;

            return $this->json($this->payload($page));
        } catch (StaleWrite) {
            return $this->json(['error' => 'Inzwischen wurde ein neuerer Stand gespeichert. Deine Änderungen bleiben im Editor. Lade sie als JSON herunter, bevor du den aktuellen Serverstand lädst.', 'conflict' => true], 409);
        } catch (InvalidDocument $e) {
            return $this->json(['error' => 'Bitte prüfe die Inhalte: '.$e->getMessage()], 422);
        } catch (\JsonException|\InvalidArgumentException) {
            return $this->json(['error' => 'Die Anfrage enthält kein gültiges Seitendokument oder keine gültige Version.'], 422);
        }
    }

    private function page(string $id): array
    {
        return $this->pages->findForEditor($id) ?? throw $this->createNotFoundException('Seite nicht gefunden.');
    }

    private function payload(array $page): array
    {
        return ['document' => $page['document'], 'version' => $page['version'], 'revisionId' => $page['draft_revision_id'], 'publishedRevisionId' => $page['published_revision_id'], 'csrfToken' => $this->csrf->getToken('editor')->getValue()];
    }
}