WP-LIT-MCP/src/Integrations/Divi/Release/WriteProbe.php

<?php

declare(strict_types=1);

namespace LIT\MCP\Integrations\Divi\Release;

use LIT\MCP\Abilities\Errors;
use LIT\MCP\Integrations\Divi\Pages\DiviPages;
use LIT\MCP\Integrations\WordPress\Content\ContentComposer;
use LIT\MCP\Integrations\WordPress\Render\PageRenderer;
use Throwable;
use WP_Error;
use WP_Post;

defined('ABSPATH') || exit;

/**
 * Spec §6.2 step 4: a throwaway draft page written through the normal Divi write path (ContentComposer → Composer
 * → Serializer → DiviSaver, with the release lock opened for this page only), checked (content, builder flags,
 * Divi renders every module without a PHP warning from Divi's files) and always deleted for good – in finally,
 * not to the trash, with its revisions and meta. Pages a dead check left behind carry MARKER; removeOrphans()
 * deletes them. No change log entry. Not final so CompatibilityCheck can be tested with a mock.
 */
class WriteProbe
{
    public const MARKER = '_lit_mcp_check_page';

    public const TITLE = '[LIT MCP Prüfung]';

    /** Everyday modules without media, each with a text to find in the rendered page. */
    public const SECTIONS = [[
        'type' => 'section',
        'label' => 'LIT MCP Prüfung',
        'rows' => [
            [
                'columns' => '1_2,1_2',
                'modules' => [
                    [
                        ['type' => 'heading', 'text' => 'litcheck-heading', 'level' => 'h2'],
                        ['type' => 'text', 'content' => '<p>litcheck-text</p>'],
                        ['type' => 'button', 'text' => 'litcheck-button', 'url' => '/'],
                    ],
                    [
                        ['type' => 'blurb', 'title' => 'litcheck-blurb', 'content' => '<p>litcheck-blurb-text</p>'],
                        [
                            'type' => 'cta',
                            'title' => 'litcheck-cta',
                            'button_text' => 'litcheck-cta-button',
                            'button_url' => '/',
                        ],
                        ['type' => 'divider'],
                    ],
                ],
            ],
            [
                'columns' => '4_4',
                'modules' => [
                    ['type' => 'toggle', 'title' => 'litcheck-toggle', 'content' => '<p>litcheck-toggle-text</p>'],
                    ['type' => 'accordion', 'items' => [['title' => 'litcheck-accordion', 'content' => '<p>a</p>']]],
                    ['type' => 'tabs', 'items' => [['title' => 'litcheck-tab', 'content' => '<p>t</p>']]],
                    ['type' => 'icon-list', 'items' => [['text' => 'litcheck-icon-list']]],
                ],
            ],
        ],
    ]];

    public const TEXTS = [
        'litcheck-heading', 'litcheck-text', 'litcheck-button', 'litcheck-blurb', 'litcheck-cta', 'litcheck-toggle',
        'litcheck-accordion', 'litcheck-tab', 'litcheck-icon-list',
    ];

    /** Only pages older than this are orphans – a running check's page is younger. */
    private const ORPHAN_AGE = '10 minutes ago';

    /**
     * @param string|null $diviDir PHP warnings from files below it fail the check; null = DiviEnvironment::themeDir().
     */
    public function __construct(
        private ContentComposer $composer,
        private ?PageRenderer $renderer = null,
        private ?string $diviDir = null
    ) {
    }

    /** @return list<string> German problems; [] = green. */
    public function run(): array
    {
        $id = wp_insert_post([
            'post_type' => 'page',
            'post_status' => 'draft',
            'post_title' => self::TITLE . ' ' . gmdate('Y-m-d H:i'),
            'post_content' => '',
            'meta_input' => [self::MARKER => '1'],
        ], true);
        if ($id instanceof WP_Error || (int) $id <= 0) {
            return ['Die Testseite konnte nicht angelegt werden: '
                . ($id instanceof WP_Error ? $id->get_error_message() : 'keine ID')];
        }
        $id = (int) $id;

        try {
            $problems = $this->exercise($id);
        } catch (Throwable $e) {
            $problems = ['Schreibtest abgebrochen: ' . $e->getMessage()];
        } finally {
            if (! self::delete($id)) {
                $problems[] = sprintf(
                    'Die Testseite %d konnte nicht gelöscht werden; bitte unter Seiten endgültig löschen.',
                    $id
                );
            }
        }

        return $problems;
    }

    /**
     * @return list<int> IDs of check pages a dead check left behind, deleted now. Only drafts whose title starts
     *     with self::TITLE are considered – the marker meta alone is not enough (it is only a query hint here).
     */
    public static function removeOrphans(): array
    {
        $posts = get_posts([
            'post_type' => 'page',
            'post_status' => 'draft',
            // phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_key -- a handful of marked pages at most.
            'meta_key' => self::MARKER,
            'date_query' => [['before' => self::ORPHAN_AGE, 'column' => 'post_date_gmt']],
            'fields' => 'all',
            'posts_per_page' => 20,
            'no_found_rows' => true,
            'suppress_filters' => true,
        ]);

        $removed = [];
        foreach (is_array($posts) ? $posts : [] as $post) {
            if (! $post instanceof WP_Post || ! str_starts_with((string) $post->post_title, self::TITLE)) {
                continue;
            }
            if (self::delete((int) $post->ID)) {
                $removed[] = (int) $post->ID;
            }
        }

        return $removed;
    }

    /** @return list<string> */
    private function exercise(int $id): array
    {
        $written = ReleaseGate::whileProbing(
            $id,
            fn (): array|WP_Error => $this->composer->write($id, 'page', self::SECTIONS)
        );
        if ($written instanceof WP_Error) {
            return ['Die Kurzform der Testseite wurde abgelehnt: ' . Errors::clientMessage($written)];
        }

        $post = get_post($id);
        if (! $post instanceof WP_Post) {
            return ['Die Testseite ist nach dem Schreiben nicht lesbar.'];
        }

        $problems = [];
        if (! str_contains((string) $post->post_content, '<!-- wp:divi/')) {
            $problems[] = 'Es wurde kein Divi-Inhalt gespeichert.';
        }
        foreach (DiviPages::FLAGS as $key => $value) {
            if (get_post_meta($id, $key, true) !== $value) {
                $problems[] = sprintf('Builder-Kennzeichen %s fehlt.', $key);
            }
        }

        [$html, $warnings] = $this->render($post);
        foreach (self::TEXTS as $text) {
            if (! str_contains($html, $text)) {
                $problems[] = sprintf('„%s“ fehlt in der gerenderten Seite.', $text);
            }
        }
        foreach ($warnings as $warning) {
            $problems[] = 'PHP-Warnung aus Divi beim Rendern: ' . $warning;
        }

        return $problems;
    }

    /** @return array{0: string, 1: list<string>} The rendered content and PHP warnings raised in Divi's files. */
    private function render(WP_Post $post): array
    {
        $dir = $this->diviDir ?? DiviEnvironment::themeDir();
        $warnings = [];
        set_error_handler(
            static function (
                int $level,
                string $message,
                string $file = '',
                int $line = 0
            ) use (
                $dir,
                &$warnings
            ): bool {
                if ($dir !== null && str_starts_with($file, $dir)) {
                    $warnings[] = sprintf('%s (%s:%d)', $message, basename($file), $line);
                }

                return false;
            },
            E_WARNING | E_USER_WARNING
        );

        try {
            $html = ($this->renderer ?? new PageRenderer())->render($post);
        } finally {
            restore_error_handler();
        }

        return [$html, $warnings];
    }

    private static function delete(int $id): bool
    {
        return wp_delete_post($id, true) instanceof WP_Post;
    }
}