<?php

declare(strict_types=1);

namespace Evomedien\Vitec\Headless;

use Netzbewegung\NbHeadlessContentBlocks\DataProcessing\ToArray\FileReferenceToArray;
use TYPO3\CMS\Core\Imaging\ImageManipulation\CropVariantCollection;
use TYPO3\CMS\Core\Utility\GeneralUtility;
use TYPO3\CMS\Extbase\Service\ImageService;

/**
 * XCLASS of the headless-content-blocks file serializer: delivers
 * processed, responsive images instead of the original upload.
 *
 * Why (Lighthouse 2026-11-10, home page score 40 / LCP 25 s / 42 MB): the
 * stock serializer emits `publicUrl` = the ORIGINAL file for every
 * content-block image field (hero_bgimage, intro_image, card images …).
 * Editors upload 4-13 MB JPEGs, so that is what every visitor downloads -
 * while news/product images already go through the ImageService.
 *
 * Output per image (additive to the stock keys id/alt/title):
 *  - publicUrl: now the processed default variant (WebP, max. 1920 px wide,
 *    editor crop applied) - the frontend needs no change to benefit.
 *  - originalUrl: the untouched upload, should anyone need it.
 *  - srcset: WebP steps 480-1920 px (steps that would fall back to the
 *    original are skipped), as {url,width,descriptor} like elsewhere.
 *  - width/height: pixel size of the default variant (aspect ratio for
 *    CLS-free layout) - mimeType alongside.
 * Non-images (video, pdf …), SVG and GIF keep the stock behaviour and only
 * gain mimeType/size (GIF processing would drop animation; SVG scales).
 *
 * Exception-safe: any processing failure falls back to the stock output.
 */
class ProcessedFileReferenceToArray extends FileReferenceToArray
{
    private const DEFAULT_WIDTH = 1920;
    private const SRCSET_WIDTHS = [480, 768, 1024, 1440, 1920];
    private const SKIP_EXTENSIONS = ['svg', 'gif'];

    public function toArray(): array
    {
        $data = parent::toArray();

        try {
            $file = $this->fileReference;
            $mimeType = (string)$file->getMimeType();
            $extension = strtolower((string)$file->getExtension());

            // Alt-text fallback (Seobility: 215 pages with empty alt): the
            // reference title, then the file's title property. Editors can
            // still override per reference.
            if (trim((string)($data['alt'] ?? '')) === '') {
                $fallbackAlt = trim((string)($file->getTitle() ?? ''));
                if ($fallbackAlt === '') {
                    $fallbackAlt = trim((string)($file->getOriginalFile()->getProperty('title') ?? ''));
                }
                if ($fallbackAlt !== '') {
                    $data['alt'] = $fallbackAlt;
                }
            }

            $data['mimeType'] = $mimeType;
            $data['size'] = (int)$file->getSize();

            if (!str_starts_with($mimeType, 'image/') || in_array($extension, self::SKIP_EXTENSIONS, true)) {
                if (str_starts_with($mimeType, 'image/')) {
                    $data['width'] = (int)$file->getProperty('width');
                    $data['height'] = (int)$file->getProperty('height');
                }
                return $data;
            }

            $crop = null;
            if ($file->hasProperty('crop') && $file->getProperty('crop')) {
                $cropArea = CropVariantCollection::create((string)$file->getProperty('crop'))->getCropArea('default');
                if (!$cropArea->isEmpty()) {
                    $crop = $cropArea->makeAbsoluteBasedOnFile($file);
                }
            }

            $imageService = GeneralUtility::makeInstance(ImageService::class);
            $instructions = static fn (int $width): array => array_filter([
                'width' => $width,
                'crop' => $crop,
                'fileExtension' => 'webp',
            ], static fn ($v) => $v !== null);

            $default = $imageService->applyProcessingInstructions($file, $instructions(self::DEFAULT_WIDTH));

            $srcset = [];
            foreach (self::SRCSET_WIDTHS as $width) {
                $variant = $imageService->applyProcessingInstructions($file, $instructions($width));
                if ($variant->usesOriginalFile()) {
                    continue;
                }
                $srcset[] = [
                    'url' => $imageService->getImageUri($variant, true),
                    'width' => (int)$variant->getProperty('width'),
                    'descriptor' => (int)$variant->getProperty('width') . 'w',
                ];
            }

            $data['originalUrl'] = (string)($data['publicUrl'] ?? '');
            $data['originalSize'] = (int)$file->getSize();
            $data['publicUrl'] = $imageService->getImageUri($default, true);
            $data['width'] = (int)$default->getProperty('width');
            $data['height'] = (int)$default->getProperty('height');
            $data['size'] = (int)$default->getSize();
            $data['srcset'] = $srcset;
            $data['mimeType'] = (string)($default->getMimeType() ?: 'image/webp');
        } catch (\Throwable $e) {
            // keep the stock payload
        }

        return $data;
    }
}