<?php

declare(strict_types=1);

namespace Evomedien\EvoMegamenuJson\UserFunc;

use Doctrine\DBAL\ParameterType;
use Evomedien\EvoMegamenuJson\Service\MenuBuilder;
use TYPO3\CMS\Core\Attribute\AsAllowedCallable;
use TYPO3\CMS\Core\Database\ConnectionPool;
use TYPO3\CMS\Core\Database\Query\Restriction\FrontendRestrictionContainer;
use TYPO3\CMS\Core\Utility\GeneralUtility;
use TYPO3\CMS\Frontend\ContentObject\ContentObjectRenderer;

/**
 * Emits one megamenu as JSON. Serves both wiring points:
 *
 *   - as a field of the plugin's own content element (no configuration -
 *     the element renders itself),
 *   - as a page-level field for the site header, configured with either
 *     `contentUid` (a specific plugin element) or `storagePid` (the first
 *     megamenu element found on that folder).
 *
 * TYPO3 v14 hands the ContentObjectRenderer in through the setter rather
 * than the constructor; without it $this->cObj stays null and the element
 * path cannot see which record it is rendering.
 */
final class MegamenuJsonRenderer
{
    private const CTYPE = 'evomegamenujson_megamenu';

    protected ?ContentObjectRenderer $cObj = null;

    public function setContentObjectRenderer(ContentObjectRenderer $cObj): void
    {
        $this->cObj = $cObj;
    }

    /**
     * @param array<string,mixed> $conf TypoScript: contentUid, storagePid
     */
    #[AsAllowedCallable]
    public function render(string $content, array $conf): string
    {
        try {
            $cObj = $this->cObj ?? GeneralUtility::makeInstance(ContentObjectRenderer::class);
            $row = null;
            $uid = (int)($conf['contentUid'] ?? 0);

            if ($uid <= 0) {
                $data = is_array($cObj->data ?? null) ? $cObj->data : [];
                if ((string)($data['CType'] ?? '') === self::CTYPE) {
                    // rendering the element itself
                    $row = $data;
                    $uid = (int)($data['uid'] ?? 0);
                }
            }
            if ($uid <= 0 && (int)($conf['storagePid'] ?? 0) > 0) {
                $uid = $this->firstElementOn((int)$conf['storagePid']);
            }
            if ($uid <= 0) {
                return '';
            }

            $menu = GeneralUtility::makeInstance(MenuBuilder::class)->build($uid, $cObj, $row);

            return (string)json_encode($menu, JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE);
        } catch (\Throwable) {
            // A broken menu must never take the page payload down with it.
            return '';
        }
    }

    /** uid of the first megamenu element on a storage folder, 0 when none. */
    private function firstElementOn(int $pid): int
    {
        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable('tt_content');
        $queryBuilder->setRestrictions(GeneralUtility::makeInstance(FrontendRestrictionContainer::class));
        $uid = $queryBuilder->select('uid')->from('tt_content')
            ->where(
                $queryBuilder->expr()->eq('pid', $queryBuilder->createNamedParameter($pid, ParameterType::INTEGER)),
                $queryBuilder->expr()->eq('CType', $queryBuilder->createNamedParameter(self::CTYPE))
            )
            ->orderBy('sorting', 'ASC')
            ->setMaxResults(1)
            ->executeQuery()->fetchOne();

        return is_numeric($uid) ? (int)$uid : 0;
    }
}