<?php

declare(strict_types=1);

namespace Evomedien\Vitec\Controller\Backend;

use Evomedien\Vitec\Service\SsrPurgeService;
use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\ServerRequestInterface;
use TYPO3\CMS\Backend\Attribute\AsController;
use TYPO3\CMS\Backend\Routing\UriBuilder;
use TYPO3\CMS\Backend\Template\Components\ButtonBar;
use TYPO3\CMS\Backend\Template\Components\ComponentFactory;
use TYPO3\CMS\Backend\Template\ModuleTemplateFactory;
use TYPO3\CMS\Backend\Utility\BackendUtility;
use TYPO3\CMS\Core\Core\Environment;
use TYPO3\CMS\Core\Database\Connection;
use TYPO3\CMS\Core\Database\ConnectionPool;
use TYPO3\CMS\Core\Http\JsonResponse;
use TYPO3\CMS\Core\Http\RedirectResponse;
use TYPO3\CMS\Core\Http\RequestFactory;
use TYPO3\CMS\Core\Messaging\FlashMessage;
use TYPO3\CMS\Core\Site\SiteFinder;
use TYPO3\CMS\Core\Messaging\FlashMessageService;
use TYPO3\CMS\Core\Page\PageRenderer;
use TYPO3\CMS\Core\Type\ContextualFeedbackSeverity;
use TYPO3\CMS\Core\Utility\GeneralUtility;

/**
 * Backend module "VITEC SSR": live state of the SSR node, manual purge
 * (single paths or everything) and the purge/health protocol.
 */
#[AsController]
final class SsrController
{
    public function __construct(
        private readonly ModuleTemplateFactory $moduleTemplateFactory,
        private readonly SsrPurgeService $purgeService,
        private readonly RequestFactory $requestFactory,
        private readonly ConnectionPool $connectionPool,
        private readonly FlashMessageService $flashMessageService,
        private readonly UriBuilder $uriBuilder,
        private readonly PageRenderer $pageRenderer,
        private readonly ComponentFactory $componentFactory,
    ) {}

    public function indexAction(ServerRequestInterface $request): ResponseInterface
    {
        $view = $this->moduleTemplateFactory->create($request);
        $view->setTitle('VITEC SSR');

        [$health, $healthError] = $this->fetchHealth();
        $this->pageRenderer->loadJavaScriptModule('@evomedien/vitec/ssr-warm-progress.js');
        $this->pageRenderer->loadJavaScriptModule('@evomedien/vitec/ssr-module.js');
        $this->pageRenderer->addCssFile('EXT:vitec/Resources/Public/Css/backend-ssr.css');

        // DocHeader: shortcut button (0096-FE); the reload button comes from the core.
        $view->addButtonToButtonBar(
            $this->componentFactory->createShortcutButton()
                ->setRouteIdentifier('web_vitecssr')
                ->setDisplayName('VITEC SSR'),
            ButtonBar::BUTTON_POSITION_RIGHT
        );

        $limit = (int)($request->getQueryParams()['limit'] ?? 30);
        if (!in_array($limit, [30, 100, 500], true)) {
            $limit = 30;
        }
        $healthLog = $this->rows('tx_vitec_ssrhealthlog', 10);
        $lastSample = $healthLog[0] ?? null;

        $view->assignMultiple([
            'flagOn' => file_exists(Environment::getVarPath() . '/vitec-ssr-on.flag'),
            'configured' => $this->purgeService->isConfigured(),
            'health' => $health,
            'healthError' => $healthError,
            'cacheLimitMb' => $this->purgeService->getCacheLimitMb(),
            'lastSample' => $lastSample,
            'lastSampleAge' => $lastSample ? BackendUtility::calcAge(time() - (int)$lastSample['crdate']) : '',
            'purgeLog' => $this->purgeRows($limit),
            'purgeLimit' => $limit,
            'moduleUri' => (string)$this->uriBuilder->buildUriFromRoute('web_vitecssr'),
            'healthLog' => $healthLog,
            'clientErrors' => $this->clientErrors(50),
            'clientErrorCount24h' => $this->clientErrorCount24h(),
        ]);
        return $view->renderResponse('Ssr/Index');
    }

    /**
     * Client error reports of the last 24 hours (POST /api/vitec/client-error,
     * ClientErrorMiddleware), newest first. Rows carry a "host" (URL without
     * scheme/query) and a shortened user agent for the table; the full
     * values stay in the row for the details toggle.
     */
    private function clientErrors(int $limit): array
    {
        try {
            $qb = $this->connectionPool->getQueryBuilderForTable('tx_vitec_clienterrorlog');
            $rows = $qb->select('*')->from('tx_vitec_clienterrorlog')
                ->where($qb->expr()->gt('crdate', $qb->createNamedParameter(time() - 86400, Connection::PARAM_INT)))
                ->orderBy('uid', 'DESC')->setMaxResults($limit)
                ->executeQuery()->fetchAllAssociative();
        } catch (\Throwable) {
            return [];
        }
        foreach ($rows as &$row) {
            $path = (string)(parse_url((string)$row['url'], PHP_URL_PATH) ?? '');
            $row['path'] = $path !== '' ? $path : (string)$row['url'];
            $ua = (string)$row['user_agent'];
            $row['ua_short'] = mb_strlen($ua) > 60 ? mb_substr($ua, 0, 57) . '...' : $ua;
            $row['is_chunk_reload'] = str_contains(strtolower((string)$row['message']), 'chunk reload');
        }
        unset($row);
        return $rows;
    }

    /**
     * Purge log rows prepared for the template: trigger split into a short
     * label plus the user, paths as count + first two + the rest behind a
     * disclosure (the raw list was a wall of text, 0096-FE).
     */
    private function purgeRows(int $limit): array
    {
        $rows = $this->rows('tx_vitec_ssrpurgelog', $limit);
        foreach ($rows as &$row) {
            $trigger = (string)$row['trigger_source'];
            $who = '';
            if (str_contains($trigger, ':')) {
                [$trigger, $who] = explode(':', $trigger, 2);
            }
            $row['trigger_label'] = match ($trigger) {
                'module' => 'manual',
                'contextmenu' => 'context menu',
                'editor-save', 'editor-command' => 'auto-purge',
                default => $trigger,
            };
            $row['trigger_who'] = $who;
            $row['trigger_badge'] = match ($trigger) {
                'module', 'contextmenu' => 'badge-info',
                'switch-on' => 'badge-warning',
                default => 'badge-secondary',
            };
            $paths = preg_split('/\s*,\s*/', trim((string)$row['paths']), -1, PREG_SPLIT_NO_EMPTY) ?: [];
            $row['paths_all'] = $paths === ['*'];
            $row['paths_count'] = count($paths);
            $row['paths_first'] = array_slice($paths, 0, 2);
            $row['paths_rest'] = array_slice($paths, 2);
        }
        unset($row);
        return $rows;
    }

    private function clientErrorCount24h(): int
    {
        try {
            return (int)$this->connectionPool->getConnectionForTable('tx_vitec_clienterrorlog')
                ->executeQuery('SELECT COUNT(*) FROM tx_vitec_clienterrorlog WHERE crdate > ?', [time() - 86400])
                ->fetchOne();
        } catch (\Throwable) {
            return 0;
        }
    }

    public function purgeAction(ServerRequestInterface $request): ResponseInterface
    {
        $body = (array)$request->getParsedBody();
        $mode = (string)($body['mode'] ?? 'paths');
        $user = (string)($GLOBALS['BE_USER']->user['username'] ?? '?');

        if ($mode === 'all') {
            $paths = ['*'];
        } else {
            $paths = preg_split('/[\s,]+/', (string)($body['paths'] ?? ''), -1, PREG_SPLIT_NO_EMPTY) ?: [];
        }

        if ($paths === []) {
            $this->flash('No paths given.', 'Purge', false);
        } else {
            $result = $this->purgeService->purge($paths, 'module:' . $user);
            $this->flash(
                sprintf('HTTP %d — %s', $result['httpCode'], $result['message']),
                $result['success'] ? 'Purge successful' : 'Purge failed',
                $result['success']
            );
        }
        return new RedirectResponse((string)$this->uriBuilder->buildUriFromRoute('web_vitecssr'), 303);
    }

    /**
     * "Warm cache" button: asks the node to render every page of the
     * sitemap in the background (0066-FE). Returns at once; progress is
     * the "Cache warming" row of the status table.
     */
    public function warmAction(ServerRequestInterface $request): ResponseInterface
    {
        $result = $this->purgeService->warm();
        $this->flash(
            $result['message'],
            $result['success'] ? 'Cache warming' : 'Cache warming failed',
            $result['success']
        );
        return new RedirectResponse((string)$this->uriBuilder->buildUriFromRoute('web_vitecssr'), 303);
    }

    /**
     * Ajax route vitec_ssr_purge_page: purge exactly one page, called by
     * the page tree context menu item (ssr-context-menu.js).
     */
    public function purgePage(ServerRequestInterface $request): ResponseInterface
    {
        $body = (array)($request->getParsedBody() ?? []);
        $pageUid = (int)($body['pageUid'] ?? ($request->getQueryParams()['pageUid'] ?? 0));
        if ($pageUid <= 0) {
            return new JsonResponse(['success' => false, 'message' => 'No page uid given'], 400);
        }
        try {
            $site = GeneralUtility::makeInstance(SiteFinder::class)->getSiteByPageId($pageUid);
            $path = $site->getRouter()->generateUri($pageUid)->getPath() ?: '/';
        } catch (\Throwable) {
            return new JsonResponse(['success' => false, 'message' => 'Page has no routable URL (folder?)']);
        }
        $user = (string)($GLOBALS['BE_USER']->user['username'] ?? '?');
        $result = $this->purgeService->purge([$path], 'contextmenu:' . $user);
        return new JsonResponse([
            'success' => $result['success'],
            'path' => $path,
            'message' => 'HTTP ' . $result['httpCode'] . ' - ' . $result['message'],
        ]);
    }

    /**
     * GET /__health of the SSR node. Returns [health array|null, error string].
     */
    private function fetchHealth(): array
    {
        $endpoint = $this->purgeService->getHealthEndpoint();
        if ($endpoint === '') {
            return [null, 'var/vitec-ssr-purge.env missing or incomplete.'];
        }
        $start = microtime(true);
        try {
            $response = $this->requestFactory->request($endpoint, 'GET', [
                'timeout' => 3, 'connect_timeout' => 2, 'http_errors' => false,
            ]);
            if ($response->getStatusCode() !== 200) {
                return [null, 'HTTP ' . $response->getStatusCode()];
            }
            $health = json_decode((string)$response->getBody(), true) ?: null;
            if ($health === null) {
                return [null, 'invalid JSON from /__health'];
            }
            $health['responseMs'] = (int)round((microtime(true) - $start) * 1000);
            return [$health, ''];
        } catch (\Throwable $e) {
            return [null, $e->getMessage()];
        }
    }

    /**
     * Ajax route vitec_ssr_health: live status for the module's
     * "Cache warming" progress bar (ssr-warm-progress.js polls it).
     */
    public function healthJson(ServerRequestInterface $request): ResponseInterface
    {
        [$health, $error] = $this->fetchHealth();
        return new JsonResponse(['health' => $health, 'error' => $error]);
    }

    private function rows(string $table, int $limit): array
    {
        try {
            $qb = $this->connectionPool->getQueryBuilderForTable($table);
            return $qb->select('*')->from($table)
                ->orderBy('uid', 'DESC')->setMaxResults($limit)
                ->executeQuery()->fetchAllAssociative();
        } catch (\Throwable) {
            return [];
        }
    }

    private function flash(string $message, string $title, bool $ok): void
    {
        $flash = GeneralUtility::makeInstance(
            FlashMessage::class,
            $message,
            $title,
            $ok ? ContextualFeedbackSeverity::OK : ContextualFeedbackSeverity::ERROR,
            true
        );
        $this->flashMessageService->getMessageQueueByIdentifier()->addMessage($flash);
    }
}