<?php

declare(strict_types=1);

namespace App\Controller\Booking\Edit;

use App\BusProNet\Model\Notification;
use App\Entity\User;
use App\Exception\TravelNotFoundException;
use App\Form\BookingEditType;
use App\Form\Model\BookingDto;
use App\Htmx\HxTrait;
use App\Model\BookingEditSubmissionResult;
use App\Service\BookingChangeTracker;
use App\Service\BookingEditContextFactory;
use App\Service\BookingEditDataLoader;
use App\Service\BookingEditDraftManager;
use App\Service\BookingEditSubmitter;
use App\Service\BookingSessionManager;
use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\Routing\Attribute\Route;
use Symfony\Component\Security\Http\Attribute\IsGranted;

/**
 * Edit controller using card-based participant interface.
 *
 * This controller implements the card-based UI for editing existing bookings:
 * - Card overview with lazy-loaded individual participant forms
 * - Handles canceled participants (status 'S')
 * - Applies mutability constraints via EditFieldStateProvider
 * - Final submission is delegated to BookingEditSubmitter
 */
class IndexController extends AbstractController
{
    use HxTrait;

    public function __construct(
        private readonly BookingEditDataLoader $dataLoader,
        private readonly BookingEditDraftManager $draftService,
        private readonly BookingSessionManager $bookingSessionService,
        private readonly BookingChangeTracker $fingerprintService,
        private readonly BookingEditContextFactory $editContextFactory,
        private readonly BookingEditSubmitter $formSubmitter,
    ) {
    }

    /**
     * Entry point for editing a booking from the booking list.
     *
     * Clears any existing session data and API cache to ensure fresh data
     * is loaded, then redirects to the main edit page.
     */
    #[Route('/bookings/{bookingId}/edit/start', name: 'app_booking_edit_start', requirements: ['bookingId' => '\d+'])]
    #[IsGranted('ROLE_USER')]
    public function start(int $bookingId, Request $request): Response
    {
        /** @var User $user */
        $user = $this->getUser();

        $this->bookingSessionService->clearBookingDto($request, BookingDto::MODE_EDIT);
        $this->dataLoader->invalidateBookingCache($bookingId, $user);

        return $this->redirectToRoute('app_booking_edit', ['bookingId' => $bookingId]);
    }

    /**
     * Display participant cards overview.
     */
    #[Route('/bookings/{bookingId}/edit', name: 'app_booking_edit', requirements: ['bookingId' => '\d+'])]
    #[IsGranted('ROLE_USER')]
    public function index(int $bookingId, Request $request): Response
    {
        /** @var User $user */
        $user = $this->getUser();

        // Load form data from session (or API on first load)
        try {
            $bookingDto = $this->dataLoader->loadFormData($request, $bookingId, $user);
        } catch (TravelNotFoundException) {
            $this->addFlash('error', 'Reisedaten sind nicht (mehr) verfügbar');

            return $this->redirectToRoute('app_bookings');
        }

        if (null === $bookingDto) {
            $this->addFlash('error', 'Buchungsdaten nicht (mehr) verfügbar');

            return $this->redirectToRoute('app_bookings');
        }

        // Show flash message if draft was restored
        if (true === $this->dataLoader->isDraftRestored()) {
            $this->addFlash('info', 'Dein zuvor gespeicherter Entwurf wurde wiederhergestellt.');
        }

        // Fetch booking data for display (surcharges, canceled status, etc.)
        $bookingData = $this->dataLoader->fetchBookingData($bookingId, $user);
        if (null === $bookingData || $bookingData instanceof Notification) {
            $this->addFlash('error', 'Buchungsdaten nicht (mehr) verfügbar');

            return $this->redirectToRoute('app_bookings');
        }

        // Create validation form (same pattern as CreateStep2Controller)
        $form = $this->createForm(BookingEditType::class, $bookingDto);
        $form->handleRequest($request);

        // Handle form submission (clicking "Buchung aktualisieren")
        if ($form->isSubmitted() && $form->isValid()) {
            $submissionResult = $this->formSubmitter->handleSubmission($request, $bookingDto, $bookingId, $user);
            $this->applySubmissionResultFlashes($submissionResult);

            return $this->redirectToRoute('app_booking_edit', ['bookingId' => $bookingId]);
        }

        $bookingEditContext = $this->editContextFactory->createOverviewContext(
            $bookingDto,
            $bookingData,
            $this->fingerprintService->isDirty($bookingDto),
            $form->isSubmitted(),
            $form->isSubmitted() && false === $form->isValid(),
        );

        $templateData = [
            'form' => $form->createView(),
            'bookingEditContext' => $bookingEditContext,
        ];

        return $this->render('booking/edit/index.html.twig', $templateData);
    }

    private function applySubmissionResultFlashes(BookingEditSubmissionResult $result): void
    {
        if (true === $result->immutableChangesReverted) {
            $this->addFlash('info', 'Einige Änderungen wurden verworfen, da sie aktuell nicht mehr änderbar sind.');
        }

        switch ($result->status) {
            case BookingEditSubmissionResult::STATUS_BOOKING_DATA_RELOAD_FAILED:
                $this->addFlash('error', 'Buchungsdaten konnten vor dem Speichern nicht neu geladen werden');
                break;
            case BookingEditSubmissionResult::STATUS_NOTIFICATION_ERROR:
                $this->addFlash('error', $result->message ?? 'Es ist ein Fehler in der Kommunikation mit dem Buchungssystem aufgetreten');
                break;
            case BookingEditSubmissionResult::STATUS_NOTIFICATION_INFO:
                if (null !== $result->message && '' !== trim($result->message)) {
                    $this->addFlash('info', $result->message);
                }
                break;
            case BookingEditSubmissionResult::STATUS_SUCCESS:
                $this->addFlash('success', 'Buchung erfolgreich aktualisiert');
                $this->addFlash('booking_edit_notice', 'Bitte ladet euch eine aktualisierte Rechnung herunter, damit ihr stets den aktuellen Stand eurer Buchung vorliegen habt.');
                break;
            case BookingEditSubmissionResult::STATUS_UNSUCCESSFUL:
                $this->addFlash('error', $result->message ?? 'Buchung konnte nicht aktualisiert werden');
                break;
            case BookingEditSubmissionResult::STATUS_TIMEOUT:
                $this->addFlash('error', 'Die Anfrage hat zu lange gedauert. Bitte versuche es erneut.');
                break;
            case BookingEditSubmissionResult::STATUS_API_CLIENT_ERROR:
                $this->addFlash('error', 'Es ist ein Fehler in der Kommunikation mit dem Buchungssystem aufgetreten');
                break;
        }
    }

    /**
     * Reloads booking data from API, discarding all session changes.
     *
     * GET: Returns modal HTML for confirmation
     * POST: Clears session and redirects to reload the booking
     */
    #[Route(
        path: '/bookings/{bookingId}/edit/reload',
        name: 'app_booking_edit_reload',
        requirements: ['bookingId' => '\d+']
    )]
    #[IsGranted('ROLE_USER')]
    public function reloadFromApi(int $bookingId, Request $request): Response
    {
        if (Request::METHOD_POST === $request->getMethod()) {
            // Clear session to discard all changes
            $this->bookingSessionService->clearBookingDto($request, BookingDto::MODE_EDIT);

            // Delete draft since user explicitly chose to discard changes
            /** @var User $user */
            $user = $this->getUser();
            $this->draftService->deleteDraft($user, $bookingId);

            $this->addFlash('success', 'Änderungen verworfen, Daten neu geladen');

            return $this->redirectToRoute('app_booking_edit', ['bookingId' => $bookingId]);
        }

        return $this->render('booking/edit/modal_reload.html.twig', [
            'bookingId' => $bookingId,
        ]);
    }

    /**
     * Handles "Zurück" button - clears session and preserves draft.
     *
     * Draft is preserved so the user can continue editing later.
     * Shows a flash message informing about the saved draft.
     */
    #[Route(
        path: '/bookings/{bookingId}/edit/cancel',
        name: 'app_booking_edit_cancel',
        requirements: ['bookingId' => '\d+']
    )]
    #[IsGranted('ROLE_USER')]
    public function cancelEdit(int $bookingId, Request $request): Response
    {
        // Clear session state
        $this->bookingSessionService->clearBookingDto($request, BookingDto::MODE_EDIT);

        // Check if a draft exists to show appropriate message
        /** @var User $user */
        $user = $this->getUser();
        $draft = $this->draftService->findDraft($user, $bookingId);

        if (null !== $draft) {
            $this->addFlash('info', 'Deine Änderungen wurden als Entwurf gespeichert.');
        }

        return $this->redirectToRoute('app_bookings');
    }
}