<?php

declare(strict_types=1);

namespace Evomedien\Vitec\UserFunc;


use TYPO3\CMS\Core\Attribute\AsAllowedCallable;
use Doctrine\DBAL\ParameterType;
use TYPO3\CMS\Core\Core\Environment;
use TYPO3\CMS\Core\Database\ConnectionPool;
use TYPO3\CMS\Core\Resource\ResourceFactory;
use TYPO3\CMS\Core\Service\FlexFormService;
use Evomedien\Vitec\Service\RteResolver;
use TYPO3\CMS\Core\Utility\GeneralUtility;
use TYPO3\CMS\Extbase\Service\ImageService;

/**
 * UserFunc to render the Datasheets plugin as JSON.
 *
 * Lists every product that has at least one datasheet, with the LATEST
 * datasheet attached. "Datasheet" = a Download linked to the product via
 * tx_vitec_product_download_mm with hideondatasheets = 0. "Latest" is
 * the download with the highest tstamp.
 *
 * The plugin is global — the page on which it is placed is not used as
 * a filter. FlexForm settings (showFilter, showSearch, itemsPerPage)
 * are passed through for the frontend UI to honour.
 *
 * Exception-safe. Returns '' on failure / nothing to render.
 */
class DatasheetsJsonRenderer
{
    #[AsAllowedCallable]
    public function render(string $content, array $conf): string
    {
        
        $pageId = 0;
        $req = $GLOBALS["TYPO3_REQUEST"] ?? null;
        if ($req !== null) {
            $pi = $req->getAttribute("frontend.page.information");
            if ($pi !== null) { $pageId = (int)$pi->getId(); }
        }
        if ($pageId <= 0) { $pageId = (int)($GLOBALS["TSFE"]->id ?? 0); }

        $qb = GeneralUtility::makeInstance(ConnectionPool::class)
            ->getQueryBuilderForTable('tt_content');

        $rows = $qb
            ->select('*')
            ->from('tt_content')
            ->where(
                $qb->expr()->eq('pid', $qb->createNamedParameter($pageId, ParameterType::INTEGER)),
                $qb->expr()->eq('CType', $qb->createNamedParameter('vitec_datasheets', ParameterType::STRING)),
                $qb->expr()->eq('deleted', 0),
                $qb->expr()->eq('hidden', 0)
            )
            ->executeQuery()
            ->fetchAllAssociative();

        if (empty($rows)) {
            return '';
        }

        return $this->renderForRecord($rows[0]);
    }

    /**
     * @param array<string,mixed> $contentElement
     */
    public function renderForRecord(array $contentElement): string
    {
        try {
            $flexFormService = GeneralUtility::makeInstance(FlexFormService::class);
            $flexFormData = $flexFormService->convertFlexFormContentToArray($contentElement['pi_flexform'] ?? '');
            $settings = $flexFormData['settings'] ?? [];

            $debugMode = (bool)($settings['debug'] ?? false);

            $settingsOut = [
                'showFilter'   => (bool)($settings['showFilter']   ?? true),
                'showSearch'   => (bool)($settings['showSearch']   ?? true),
                'itemsPerPage' => (int)($settings['itemsPerPage']  ?? 20),
            ];

            // 1) Pull all (product_uid, latest_datasheet_uid) pairs in one query.
            // GROUP BY product, take MAX(tstamp) → join back to get that exact download.
            $items = $this->fetchProductLatestDatasheetPairs();

            // 2) Hydrate each pair: full product + full datasheet objects.
            $itemsOut = [];
            foreach ($items as $pair) {
                $productUid   = (int)$pair['product_uid'];
                $datasheetUid = (int)$pair['datasheet_uid'];

                $product   = $this->fetchProduct($productUid);
                $datasheet = $this->fetchDownload($datasheetUid);
                if (!$product || !$datasheet) {
                    continue;
                }

                $itemsOut[] = [
                    'product'   => $this->serializeProduct($product),
                    'datasheet' => $this->serializeDatasheet($datasheet),
                ];
            }

            $response = [
                'items'    => $itemsOut,
                'settings' => $settingsOut,
            ];

            if ($debugMode) {
                $response['debug'] = [
                    'productCount' => count($itemsOut),
                    'settings'     => $settings,
                    'fallbackFiles' => $this->collectFallbackFilesFromItems($itemsOut),
                ];
            }

            return json_encode($response);
        } catch (\Throwable $e) {
            return '';
        }
    }

    /**
     * For each visible product that has at least one visible datasheet,
     * return [product_uid => latest_datasheet_uid]. Sorted by product title.
     *
     * @return array<int,array{product_uid:int,datasheet_uid:int}>
     */
    private function fetchProductLatestDatasheetPairs(): array
    {
        $qb = GeneralUtility::makeInstance(ConnectionPool::class)
            ->getQueryBuilderForTable('tx_vitec_product_download_mm');
        $expr = $qb->expr();

        // Inner aggregation: for each product, the latest download tstamp.
        // We use a single query with JOIN on the same (mm + download) to resolve
        // the actual download_uid matching MAX(tstamp). Approach: do it in two
        // simple steps to stay SQL-portable.

        // Step A: gather all candidate (product_uid, download_uid, tstamp) tuples.
        $rows = $qb
            ->select(
                'mm.uid_local AS product_uid',
                'mm.uid_foreign AS datasheet_uid',
                'd.tstamp AS d_tstamp',
                'p.title AS p_title'
            )
            ->from('tx_vitec_product_download_mm', 'mm')
            ->join('mm', 'tx_vitec_domain_model_download', 'd', 'd.uid = mm.uid_foreign')
            ->join('mm', 'tx_vitec_domain_model_product',  'p', 'p.uid = mm.uid_local')
            ->where(
                $expr->eq('d.deleted', 0),
                $expr->eq('d.hidden', 0),
                $expr->eq('d.hideonwebsite', 0),
                $expr->eq('d.hideondatasheets', 0),
                $expr->eq('p.deleted', 0),
                $expr->eq('p.hidden', 0),
                $expr->eq('p.hideonwebsite', 0)
            )
            ->executeQuery()
            ->fetchAllAssociative();

        // Step B: reduce to {product_uid => latest datasheet} in PHP.
        $latestPerProduct = [];   // product_uid => [datasheet_uid, tstamp, title]
        foreach ($rows as $r) {
            $pUid  = (int)$r['product_uid'];
            $dUid  = (int)$r['datasheet_uid'];
            $ts    = (int)$r['d_tstamp'];
            $title = (string)$r['p_title'];

            if (!isset($latestPerProduct[$pUid]) || $ts > $latestPerProduct[$pUid]['tstamp']) {
                $latestPerProduct[$pUid] = [
                    'product_uid'   => $pUid,
                    'datasheet_uid' => $dUid,
                    'tstamp'        => $ts,
                    'title'         => $title,
                ];
            }
        }

        // Sort by product title ASC.
        usort($latestPerProduct, static fn($a, $b) => strcasecmp($a['title'], $b['title']));

        // Strip helper fields.
        return array_map(
            static fn($r) => ['product_uid' => $r['product_uid'], 'datasheet_uid' => $r['datasheet_uid']],
            $latestPerProduct
        );
    }

    /**
     * @return array<string,mixed>|false
     */
    private function fetchProduct(int $uid)
    {
        $qb = GeneralUtility::makeInstance(ConnectionPool::class)
            ->getQueryBuilderForTable('tx_vitec_domain_model_product');
        return $qb
            ->select('uid', 'title', 'slug', 'subtitle', 'teaser')
            ->from('tx_vitec_domain_model_product')
            ->where(
                $qb->expr()->eq('uid', $qb->createNamedParameter($uid, ParameterType::INTEGER)),
                $qb->expr()->eq('deleted', 0),
                $qb->expr()->eq('hidden', 0)
            )
            ->executeQuery()
            ->fetchAssociative();
    }

    /**
     * @return array<string,mixed>|false
     */
    private function fetchDownload(int $uid)
    {
        $qb = GeneralUtility::makeInstance(ConnectionPool::class)
            ->getQueryBuilderForTable('tx_vitec_domain_model_download');
        return $qb
            ->select('*')
            ->from('tx_vitec_domain_model_download')
            ->where(
                $qb->expr()->eq('uid', $qb->createNamedParameter($uid, ParameterType::INTEGER)),
                $qb->expr()->eq('deleted', 0),
                $qb->expr()->eq('hidden', 0)
            )
            ->executeQuery()
            ->fetchAssociative();
    }

    /**
     * @param array<string,mixed> $product
     * @return array<string,mixed>
     */
    private function serializeProduct(array $product): array
    {
        $uid = (int)$product['uid'];
        return [
            'uid'        => $uid,
            'title'      => (string)($product['title'] ?? ''),
            'slug'       => (string)($product['slug'] ?? ''),
            'subtitle'   => (string)($product['subtitle'] ?? ''),
            'teaser'     => (string)($product['teaser'] ?? ''),
            'link'       => '/product/' . (string)($product['slug'] ?? ''),
            'image'      => $this->getProductFirstImage($uid),
            'categories' => $this->getProductCategories($uid),
        ];
    }

    /**
     * @param array<string,mixed> $download
     * @return array<string,mixed>
     */
    private function serializeDatasheet(array $download): array
    {
        $uid = (int)$download['uid'];
        $filetype = $this->getDownloadFileType($uid);
        return [
            'uid'         => $uid,
            'title'       => (string)($download['title'] ?? ''),
            'slug'        => (string)($download['slug'] ?? ''),
            'teaser'      => (string)($download['teaser'] ?? ''),
            'description' => RteResolver::html($download['description'] ?? ''),
            'tstamp'      => (int)($download['tstamp'] ?? 0),
            'filetype'    => $filetype,
            'type'        => $this->getDownloadTypeLabel($uid),
            'file'        => $this->getDownloadFile($uid, (string)($download['fileprefix'] ?? ''), $filetype),
        ];
    }

    /**
     * Display taxonomy from the `type` category field (sys_category.type,
     * fallback title) - analogous to getDownloadFileType()/`categories`,
     * distinguished in the MM table by fieldname = 'type'.
     */
    private function getDownloadTypeLabel(int $downloadUid): string
    {
        $qb = GeneralUtility::makeInstance(ConnectionPool::class)
            ->getQueryBuilderForTable('sys_category');
        $categories = $qb
            ->select('c.type', 'c.title')
            ->from('sys_category', 'c')
            ->join(
                'c',
                'sys_category_record_mm',
                'mm',
                'mm.uid_local = c.uid AND mm.tablenames = ' .
                $qb->createNamedParameter('tx_vitec_domain_model_download', ParameterType::STRING) .
                ' AND mm.fieldname = ' .
                $qb->createNamedParameter('type', ParameterType::STRING)
            )
            ->where(
                $qb->expr()->eq('mm.uid_foreign', $qb->createNamedParameter($downloadUid, ParameterType::INTEGER)),
                $qb->expr()->eq('c.deleted', 0),
                $qb->expr()->eq('c.hidden', 0)
            )
            ->orderBy('mm.sorting', 'ASC')
            ->executeQuery()
            ->fetchAllAssociative();

        foreach ($categories as $category) {
            $label = trim((string)($category['type'] ?? ''));
            if ($label === '') {
                $label = trim((string)($category['title'] ?? ''));
            }
            if ($label !== '') {
                return $label;
            }
        }

        return '';
    }

    private function getDownloadFileType(int $downloadUid): string
    {
        $qb = GeneralUtility::makeInstance(ConnectionPool::class)
            ->getQueryBuilderForTable('sys_category');

        $categories = $qb
            ->select('c.filetype')
            ->from('sys_category', 'c')
            ->join(
                'c',
                'sys_category_record_mm',
                'mm',
                'mm.uid_local = c.uid AND mm.tablenames = ' .
                $qb->createNamedParameter('tx_vitec_domain_model_download', ParameterType::STRING) .
                ' AND mm.fieldname = ' .
                $qb->createNamedParameter('categories', ParameterType::STRING)
            )
            ->where(
                $qb->expr()->eq('mm.uid_foreign', $qb->createNamedParameter($downloadUid, ParameterType::INTEGER)),
                $qb->expr()->eq('c.deleted', 0),
                $qb->expr()->eq('c.hidden', 0),
                $qb->expr()->eq('c.parent', $qb->createNamedParameter(4, ParameterType::INTEGER))
            )
            ->orderBy('mm.sorting', 'ASC')
            ->executeQuery()
            ->fetchAllAssociative();

        foreach ($categories as $category) {
            $filetype = trim((string)($category['filetype'] ?? ''));
            if ($filetype !== '') {
                return $filetype;
            }
        }

        return '';
    }

    /**
     * @return array<string,mixed>|null
     */
    private function getProductFirstImage(int $productUid): ?array
    {
        $qb = GeneralUtility::makeInstance(ConnectionPool::class)
            ->getQueryBuilderForTable('sys_file_reference');

        $fileRefData = $qb
            ->select('sfr.uid', 'sfr.title', 'sfr.description', 'sfr.alternative', 'sfr.crop')
            ->from('sys_file_reference', 'sfr')
            ->where(
                $qb->expr()->eq('sfr.tablenames', $qb->createNamedParameter('tx_vitec_domain_model_product', ParameterType::STRING)),
                $qb->expr()->eq('sfr.fieldname', $qb->createNamedParameter('productimage', ParameterType::STRING)),
                $qb->expr()->eq('sfr.uid_foreign', $qb->createNamedParameter($productUid, ParameterType::INTEGER)),
                $qb->expr()->eq('sfr.deleted', 0),
                $qb->expr()->eq('sfr.hidden', 0)
            )
            ->orderBy('sfr.sorting_foreign')
            ->setMaxResults(1)
            ->executeQuery()
            ->fetchAssociative();

        if (!$fileRefData) {
            return null;
        }
        try {
            $resourceFactory = GeneralUtility::makeInstance(ResourceFactory::class);
            $imageService = GeneralUtility::makeInstance(ImageService::class);
            $fileReference = $resourceFactory->getFileReferenceObject((int)$fileRefData['uid']);

            $default = $imageService->applyProcessingInstructions(
                $fileReference,
                ['width' => 400, 'crop' => $fileRefData['crop'] ?? null, 'fileExtension' => 'webp']
            );

            return [
                'uid' => (int)$fileRefData['uid'],
                'url' => $imageService->getImageUri($default),
                'title' => $fileRefData['title'] ?? '',
                'alternative' => $fileRefData['alternative'] ?? '',
                'description' => $fileRefData['description'] ?? '',
            ];
        } catch (\Exception $e) {
            return null;
        }
    }

    private function getProductCategories(int $productUid): array
    {
        $qb = GeneralUtility::makeInstance(ConnectionPool::class)
            ->getQueryBuilderForTable('sys_category');

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

        return array_map(static function ($cat) {
            return [
                'uid' => (int)$cat['uid'],
                'title' => (string)($cat['title'] ?? ''),
                'description' => (string)($cat['description'] ?? ''),
            ];
        }, $categories);
    }

    /**
     * @return array<string,mixed>|null
     */
    private function getDownloadFile(int $downloadUid, string $fileprefix = '', string $filetype = ''): ?array
    {
        $qb = GeneralUtility::makeInstance(ConnectionPool::class)
            ->getQueryBuilderForTable('sys_file_reference');

        $row = $qb
            ->select('fr.uid', 'fr.title', 'fr.description', 'f.uid AS file_uid', 'f.identifier', 'f.name', 'f.size', 'f.extension', 'f.mime_type')
            ->from('sys_file_reference', 'fr')
            ->join('fr', 'sys_file', 'f', 'fr.uid_local = f.uid')
            ->where(
                $qb->expr()->eq('fr.tablenames', $qb->createNamedParameter('tx_vitec_domain_model_download', ParameterType::STRING)),
                $qb->expr()->eq('fr.fieldname', $qb->createNamedParameter('file', ParameterType::STRING)),
                $qb->expr()->eq('fr.uid_foreign', $qb->createNamedParameter($downloadUid, ParameterType::INTEGER)),
                $qb->expr()->eq('fr.deleted', 0),
                $qb->expr()->eq('f.missing', 0)
            )
            ->orderBy('fr.sorting_foreign', 'ASC')
            ->setMaxResults(1)
            ->executeQuery()
            ->fetchAssociative();

        if (!$row) {
            return $this->resolveFileByConvention($fileprefix, $filetype)
                ?? $this->resolveFileByFilepath($downloadUid);
        }

        return [
            'uid'       => (int)$row['file_uid'],
            'name'      => (string)($row['name'] ?? ''),
            'url'       => '/fileadmin' . ($row['identifier'] ?? ''),
            'size'      => (int)($row['size'] ?? 0),
            'extension' => (string)($row['extension'] ?? ''),
            'mimeType'  => (string)($row['mime_type'] ?? ''),
            'title'     => (string)($row['title'] ?? ''),
            'description' => (string)($row['description'] ?? ''),
        ];
    }

    /**
     * Resolve file from naming convention:
     * [fileprefix]__[filetype]__[number]-[letter].ext
     * and pick highest number + highest letter.
     *
     * @return array<string,mixed>|null
     */
    private function resolveFileByConvention(string $fileprefix, string $filetype): ?array
    {
        $fileprefix = trim($fileprefix);
        $filetype = trim($filetype);
        if ($fileprefix === '' || $filetype === '') {
            return null;
        }

        $baseDir = Environment::getPublicPath() . '/fileadmin/downloads/Collateral';
        if (!is_dir($baseDir) || !is_readable($baseDir)) {
            return null;
        }

        $escapedPrefix = preg_quote($fileprefix, '/');
        $escapedType = preg_quote($filetype, '/');
        $pattern = '/^' . $escapedPrefix . '__' . $escapedType . '__(\\d+)-([A-Za-z]+)\\.([A-Za-z0-9]+)$/';

        $bestFile = null;
        $bestNumber = -1;
        $bestLetterRank = -1;

        $entries = scandir($baseDir);
        if ($entries === false) {
            return null;
        }

        foreach ($entries as $entry) {
            if (!is_string($entry) || $entry === '.' || $entry === '..') {
                continue;
            }

            if (!preg_match($pattern, $entry, $matches)) {
                continue;
            }

            $number = (int)$matches[1];
            $letter = strtoupper($matches[2]);
            $letterRank = $this->letterSequenceToRank($letter);

            if ($number > $bestNumber || ($number === $bestNumber && $letterRank > $bestLetterRank)) {
                $bestNumber = $number;
                $bestLetterRank = $letterRank;
                $bestFile = $entry;
            }
        }

        if ($bestFile === null) {
            return null;
        }

        $fullPath = $baseDir . '/' . $bestFile;
        if (!is_file($fullPath) || !is_readable($fullPath)) {
            return null;
        }

        $extension = strtolower(pathinfo($bestFile, PATHINFO_EXTENSION));
        $mimeType = function_exists('mime_content_type') ? (string)(mime_content_type($fullPath) ?: '') : '';

        return [
            'uid' => 0,
            'name' => $bestFile,
            'url' => '/fileadmin/downloads/Collateral/' . rawurlencode($bestFile),
            'size' => (int)(filesize($fullPath) ?: 0),
            'extension' => $extension,
            'mimeType' => $mimeType,
            'title' => '',
            'description' => '',
        ];
    }

    /**
     * Last-resort file resolution via the record's `filepath` column - for
     * filenames outside the <prefix>__<filetype>__<NN>-<letter> convention
     * (the 2026-08 import left a handful of such legacy names in place).
     * Same payload shape as resolveFileByConvention(). Exception-safe.
     */
    private function resolveFileByFilepath(int $downloadUid): ?array
    {
        try {
            $qb = GeneralUtility::makeInstance(ConnectionPool::class)
                ->getQueryBuilderForTable('tx_vitec_domain_model_download');
            $row = $qb
                ->select('filepath')
                ->from('tx_vitec_domain_model_download')
                ->where(
                    $qb->expr()->eq('uid', $qb->createNamedParameter($downloadUid, ParameterType::INTEGER))
                )
                ->executeQuery()
                ->fetchAssociative();

            $filepath = trim((string)($row['filepath'] ?? ''));
            if ($filepath === '') {
                return null;
            }

            $relative = '/' . ltrim($filepath, '/');
            $fullPath = Environment::getPublicPath() . $relative;
            if (!is_file($fullPath) || !is_readable($fullPath)) {
                return null;
            }

            $name = basename($fullPath);
            $extension = strtolower(pathinfo($name, PATHINFO_EXTENSION));
            $mimeType = function_exists('mime_content_type') ? (string)(mime_content_type($fullPath) ?: '') : '';

            return [
                'uid' => 0,
                'name' => $name,
                'url' => rtrim(dirname($relative), '/') . '/' . rawurlencode($name),
                'thumbnail' => null,
                'size' => (int)(filesize($fullPath) ?: 0),
                'extension' => $extension,
                'mimeType' => $mimeType,
                'title' => '',
                'description' => '',
            ];
        } catch (\Throwable $e) {
            return null;
        }
    }

    private function letterSequenceToRank(string $letters): int
    {
        $rank = 0;
        $letters = strtoupper($letters);
        $length = strlen($letters);

        for ($i = 0; $i < $length; $i++) {
            $char = ord($letters[$i]);
            if ($char < 65 || $char > 90) {
                continue;
            }

            $rank = ($rank * 26) + ($char - 64);
        }

        return $rank;
    }

    /**
     * @param array<int,array<string,mixed>> $items
     * @return array<int,array<string,mixed>>
     */
    private function collectFallbackFilesFromItems(array $items): array
    {
        $fallbackFiles = [];

        foreach ($items as $item) {
            $datasheet = $item['datasheet'] ?? null;
            if (!is_array($datasheet)) {
                continue;
            }

            $file = $datasheet['file'] ?? null;
            if (!is_array($file) || (int)($file['uid'] ?? 1) !== 0) {
                continue;
            }

            $fallbackFiles[] = [
                'datasheetUid' => (int)($datasheet['uid'] ?? 0),
                'name' => (string)($file['name'] ?? ''),
                'url' => (string)($file['url'] ?? ''),
                'source' => 'naming-convention-fallback',
            ];
        }

        return $fallbackFiles;
    }
}