<?php

declare(strict_types=1);

namespace App\Service;

use App\Email\PdfAttachment;
use App\Entity\Groups\AccommodationBooking;
use Dompdf\Dompdf;
use Dompdf\Options;
use Symfony\Component\DependencyInjection\Attribute\Autowire;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpFoundation\ResponseHeaderBag;
use Symfony\Component\String\Slugger\AsciiSlugger;
use Twig\Environment;

/**
 * Renders a one-page A4 booking document for a group accommodation booking.
 *
 * The document repeats the data of the admin detail page and includes the very same
 * price breakdown partial the booking emails use, so all three stay in sync.
 */
class AccommodationBookingPdfGenerator
{
    private const TEMPLATE = 'pdf/accommodation_booking.html.twig';
    private const LOGO_PATH = '/assets/images/logo.png';

    public function __construct(
        private readonly Environment $twig,
        private readonly AccommodationBookingBreakdownCalculator $breakdownCalculator,
        #[Autowire('%kernel.project_dir%')]
        private readonly string $projectDir,
    ) {
    }

    /**
     * @throws \RuntimeException when the booking carries no price information
     */
    public function render(AccommodationBooking $booking): string
    {
        $breakdown = $this->breakdownCalculator->compute($booking);

        if (null === $breakdown) {
            throw new \RuntimeException('Für diese Buchung liegt keine Preisaufschlüsselung vor.');
        }

        $html = $this->twig->render(self::TEMPLATE, [
            'booking' => $booking,
            'priceBreakdown' => $breakdown,
            'currency' => $booking->getPricingCurrency() ?? $breakdown['currency'],
            'logoSrc' => $this->logoDataUri(),
        ]);

        $options = new Options();
        // DejaVu Sans ships with dompdf and covers umlauts and the currency symbols
        // emitted by format_currency.
        $options->setDefaultFont('DejaVu Sans');
        $options->setDefaultPaperSize('A4');
        $options->setDefaultPaperOrientation('portrait');
        $options->setIsRemoteEnabled(false);

        $dompdf = new Dompdf($options);
        $dompdf->loadHtml($html, 'UTF-8');
        $dompdf->render();

        return (string) $dompdf->output();
    }

    /**
     * @throws \RuntimeException when the booking carries no price information
     */
    public function createDownloadResponse(AccommodationBooking $booking): Response
    {
        $response = new Response($this->render($booking));
        $response->headers->set('Content-Type', 'application/pdf');
        $response->headers->set('Content-Disposition', $response->headers->makeDisposition(
            ResponseHeaderBag::DISPOSITION_ATTACHMENT,
            $this->buildFilename($booking)
        ));

        return $response;
    }

    /**
     * Named after arrival date and group rather than the entity id, which is a local
     * detail with no counterpart in BusPro and would read as a booking number.
     */
    /**
     * @throws \RuntimeException when the booking carries no price information
     */
    public function createAttachment(AccommodationBooking $booking): PdfAttachment
    {
        return new PdfAttachment($this->render($booking), $this->buildFilename($booking));
    }

    private function buildFilename(AccommodationBooking $booking): string
    {
        $groupName = (new AsciiSlugger('de'))->slug((string) $booking->getGroupName())->lower()->toString();

        return sprintf(
            '%s-%s%s.pdf',
            mb_strtolower($booking->recordLabel()),
            $booking->getDateFrom()?->format('Y-m-d') ?? 'ohne-datum',
            '' !== $groupName ? '-'.$groupName : ''
        );
    }

    private function logoDataUri(): string
    {
        $logo = $this->projectDir.self::LOGO_PATH;

        if (false === is_readable($logo)) {
            throw new \RuntimeException('Das Logo konnte nicht gelesen werden: '.self::LOGO_PATH);
        }

        return 'data:image/png;base64,'.base64_encode((string) file_get_contents($logo));
    }
}