<?php

declare(strict_types=1);

namespace Evomedien\Vitec\Controller\Backend;

use Evomedien\Vitec\Service\StructuredDataService;
use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\ServerRequestInterface;
use TYPO3\CMS\Backend\Attribute\AsController;
use TYPO3\CMS\Core\Database\ConnectionPool;
use TYPO3\CMS\Core\Http\JsonResponse;
use TYPO3\CMS\Core\Resource\ResourceFactory;
use TYPO3\CMS\Core\Site\SiteFinder;
use TYPO3\CMS\Core\Utility\GeneralUtility;
use Doctrine\DBAL\ParameterType;

/**
 * Backend AJAX endpoint: generate schema.org JSON-LD for a single product and
 * return it as a string, ready to be written into the product's
 * `structureddata` field by the FormEngine wizard button.
 *
 * Route: vitec_structureddata_generate (see Configuration/Backend/AjaxRoutes.php)
 *
 * Generation is based on the *saved* product record (by uid); a new/unsaved
 * record returns success=false with a hint to save first. The structured data
 * is built via {@see StructuredDataService} and emitted self-contained (no
 * cross-document @id references), since the field content may be reused
 * standalone.
 */
#[AsController]
final class StructuredDataController
{
    public function __construct(
        private readonly StructuredDataService $structuredDataService,
    ) {}

    public function generate(ServerRequestInterface $request): ResponseInterface
    {
        $uid = (int)($request->getQueryParams()['uid'] ?? 0);
        if ($uid <= 0) {
            return new JsonResponse([
                'success' => false,
                'message' => 'Bitte das Produkt zuerst speichern, dann erneut generieren.',
            ]);
        }

        $product = $this->loadProduct($uid);
        if ($product === null) {
            return new JsonResponse([
                'success' => false,
                'message' => 'Produkt nicht gefunden.',
            ]);
        }

        $base = $this->resolveCanonicalBase((int)($product['pid'] ?? 0), $request);

        $data = [
            'uid' => $uid,
            'title' => (string)($product['title'] ?? ''),
            'slug' => (string)($product['slug'] ?? ''),
            'teaser' => (string)($product['teaser'] ?? ''),
            'description' => (string)($product['description'] ?? ''),
            'video' => (string)($product['video'] ?? ''),
            'categories' => $this->categories($uid),
            'videofile' => $this->videoFile($uid, $base),
        ];

        $images = $this->imageUrls($uid, $base);

        // Self-contained snippet → no @id reference to the page-level Organization.
        $productNode = $this->structuredDataService->buildProduct($data, $base, $images, false);
        $videoNode = $this->structuredDataService->buildVideoObject(
            $data,
            $base,
            $images,
            (int)($product['crdate'] ?? $product['tstamp'] ?? 0)
        );

        $nodes = array_values(array_filter([$productNode, $videoNode]));

        // One node → standalone object with @context; multiple → @graph.
        if (count($nodes) === 1) {
            $document = array_merge(['@context' => 'https://schema.org'], $nodes[0]);
        } else {
            $document = ['@context' => 'https://schema.org', '@graph' => $nodes];
        }

        $json = (string)json_encode(
            $document,
            JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE
        );

        return new JsonResponse([
            'success' => true,
            'jsonLd' => $json,
        ]);
    }

    /**
     * @return array<string,mixed>|null
     */
    private function loadProduct(int $uid): ?array
    {
        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)
            ->getQueryBuilderForTable('tx_vitec_domain_model_product');

        $row = $queryBuilder
            ->select('*')
            ->from('tx_vitec_domain_model_product')
            ->where(
                $queryBuilder->expr()->eq('uid', $queryBuilder->createNamedParameter($uid, ParameterType::INTEGER)),
                $queryBuilder->expr()->eq('deleted', 0)
            )
            ->executeQuery()
            ->fetchAssociative();

        return $row ?: null;
    }

    /**
     * @return list<array{title:string}>
     */
    private function categories(int $productUid): array
    {
        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)
            ->getQueryBuilderForTable('sys_category');

        $rows = $queryBuilder
            ->select('c.title')
            ->from('sys_category', 'c')
            ->join(
                'c',
                'sys_category_record_mm',
                'mm',
                'mm.uid_local = c.uid AND mm.tablenames = ' .
                $queryBuilder->createNamedParameter('tx_vitec_domain_model_product', ParameterType::STRING) .
                ' AND mm.fieldname = ' .
                $queryBuilder->createNamedParameter('categories', ParameterType::STRING)
            )
            ->where(
                $queryBuilder->expr()->eq('mm.uid_foreign', $queryBuilder->createNamedParameter($productUid, ParameterType::INTEGER)),
                $queryBuilder->expr()->eq('c.deleted', 0),
                $queryBuilder->expr()->eq('c.hidden', 0)
            )
            ->orderBy('mm.sorting', 'ASC')
            ->executeQuery()
            ->fetchAllAssociative();

        return array_map(static fn ($r) => ['title' => (string)($r['title'] ?? '')], $rows);
    }

    /**
     * Absolute URLs of the product images (original file public URLs).
     * Falls back to the OG image when no product images exist.
     *
     * @return string[]
     */
    private function imageUrls(int $productUid, string $base): array
    {
        $urls = $this->publicUrlsForField($productUid, 'productimage', $base);
        if ($urls === []) {
            $urls = $this->publicUrlsForField($productUid, 'ogimage', $base);
        }
        return $urls;
    }

    /**
     * @return string[]
     */
    private function publicUrlsForField(int $productUid, string $fieldName, string $base): array
    {
        $rows = $this->fileReferences($productUid, $fieldName);
        if ($rows === []) {
            return [];
        }

        $resourceFactory = GeneralUtility::makeInstance(ResourceFactory::class);
        $urls = [];
        foreach ($rows as $row) {
            try {
                $fileReference = $resourceFactory->getFileReferenceObject((int)$row['uid']);
                $publicUrl = (string)$fileReference->getOriginalFile()->getPublicUrl();
                if ($publicUrl !== '') {
                    $urls[] = $this->structuredDataService->absUrl($publicUrl, $base);
                }
            } catch (\Throwable $e) {
                continue;
            }
        }

        return $urls;
    }

    /**
     * @return array{url:string}|null
     */
    private function videoFile(int $productUid, string $base): ?array
    {
        $rows = $this->fileReferences($productUid, 'videofile');
        if ($rows === []) {
            return null;
        }

        $resourceFactory = GeneralUtility::makeInstance(ResourceFactory::class);
        try {
            $fileReference = $resourceFactory->getFileReferenceObject((int)$rows[0]['uid']);
            $publicUrl = (string)$fileReference->getOriginalFile()->getPublicUrl();
            if ($publicUrl === '') {
                return null;
            }
            return ['url' => $this->structuredDataService->absUrl($publicUrl, $base)];
        } catch (\Throwable $e) {
            return null;
        }
    }

    /**
     * @return array<int,array<string,mixed>>
     */
    private function fileReferences(int $productUid, string $fieldName): array
    {
        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)
            ->getQueryBuilderForTable('sys_file_reference');

        return $queryBuilder
            ->select('uid')
            ->from('sys_file_reference')
            ->where(
                $queryBuilder->expr()->eq('uid_foreign', $queryBuilder->createNamedParameter($productUid, ParameterType::INTEGER)),
                $queryBuilder->expr()->eq('tablenames', $queryBuilder->createNamedParameter('tx_vitec_domain_model_product', ParameterType::STRING)),
                $queryBuilder->expr()->eq('fieldname', $queryBuilder->createNamedParameter($fieldName, ParameterType::STRING)),
                $queryBuilder->expr()->eq('deleted', 0),
                $queryBuilder->expr()->eq('hidden', 0)
            )
            ->orderBy('sorting_foreign', 'ASC')
            ->executeQuery()
            ->fetchAllAssociative();
    }

    private function resolveCanonicalBase(int $pid, ServerRequestInterface $request): string
    {
        if ($pid > 0) {
            try {
                $site = GeneralUtility::makeInstance(SiteFinder::class)->getSiteByPageId($pid);
                $configured = trim((string)($site->getSettings()->get('seo.site.canonicalBase') ?? ''));
                if ($configured !== '') {
                    return rtrim($configured, '/');
                }
            } catch (\Throwable $e) {
                // fall through to request host
            }
        }

        $normalizedParams = $request->getAttribute('normalizedParams');
        if ($normalizedParams !== null) {
            return rtrim($normalizedParams->getSiteUrl(), '/');
        }

        return '';
    }
}