KantSites/src/Content/MenuRepository.php

<?php

namespace App\Content;

use App\Domain\InvalidMenu;
use App\Domain\StaleWrite;
use Doctrine\DBAL\Connection;

/**
 * Menus are small enough to live as one validated item tree per slot. An item points at a page
 * (optionally at an anchor inside it) or at an external address. Page references are resolved when
 * the menu is rendered, never stored as a path: renaming or deleting a page must not silently
 * produce a dead link.
 */
final class MenuRepository
{
    /**
     * The places a menu can be maintained for. They are not positions on the page - a menu block
     * can stand anywhere - but separate sets of entries: a header needs other links than a
     * footer, and legal links are their own short list.
     */
    public const SLOTS = [
        'header' => 'Hauptnavigation',
        'secondary' => 'Zweite Navigation',
        'footer' => 'Fußzeile',
        'legal' => 'Rechtliches',
    ];
    public const MAX_ITEMS = 60;
    public const MAX_DEPTH = 2;

    public function __construct(private Connection $db, private SiteSettings $settings)
    {
    }

    /**
     * @return array<string, array{id: string, name: string, items: array, version: int}>
     */
    public function all(string $locale = 'de'): array
    {
        $menus = [];
        foreach ($this->db->fetchAllAssociative('SELECT id, slot, name, items, version FROM menu WHERE website_id = ? AND locale = ?', ['default', $locale]) as $row) {
            $menus[$row['slot']] = [
                'id' => $row['id'], 'name' => $row['name'], 'version' => (int) $row['version'],
                'items' => json_decode($row['items'], true, 512, JSON_THROW_ON_ERROR),
            ];
        }

        return $menus;
    }

    public function save(string $slot, string $name, array $items, int $expectedVersion, string $locale = 'de'): void
    {
        if (!isset(self::SLOTS[$slot])) {
            throw new InvalidMenu('Unbekannter Menüplatz.');
        }
        $name = trim($name);
        if ('' === $name || mb_strlen($name) > 120) {
            throw new InvalidMenu('Bitte gib einen Namen mit höchstens 120 Zeichen an.');
        }
        $this->validate($items);
        $this->db->transactional(function () use ($slot, $name, $items, $expectedVersion, $locale): void {
            $encoded = json_encode($items, JSON_THROW_ON_ERROR | JSON_UNESCAPED_UNICODE);
            $existing = $this->db->fetchAssociative('SELECT id, version FROM menu WHERE website_id = ? AND locale = ? AND slot = ?', ['default', $locale, $slot]);
            if (false === $existing) {
                if (0 !== $expectedVersion) {
                    throw new StaleWrite('Das Menü wurde inzwischen angelegt. Lade die Seite neu.');
                }
                $this->db->insert('menu', ['id' => bin2hex(random_bytes(16)), 'website_id' => 'default', 'locale' => $locale, 'slot' => $slot, 'name' => $name, 'items' => $encoded, 'version' => 1]);

                return;
            }
            $changed = $this->db->executeStatement(
                'UPDATE menu SET name = ?, items = ?, version = version + 1 WHERE id = ? AND version = ?',
                [$name, $encoded, $existing['id'], $expectedVersion],
            );
            if (1 !== $changed) {
                throw new StaleWrite('Das Menü wurde inzwischen geändert. Lade die Seite neu, bevor du speicherst.');
            }
        });
    }

    /**
     * Turns the stored tree into links. Items whose page is gone or not published are dropped:
     * a deleted page must not break the navigation or expose a draft.
     *
     * @return list<array{label: string, href: string, current: bool, children: list<array>}>
     */
    public function resolve(array $items, string $currentPath, string $locale = 'de'): array
    {
        $pages = [];
        foreach ($this->db->fetchAllAssociative('SELECT id, path, published_revision_id, draft_revision_id FROM page WHERE website_id = ? AND locale = ? AND deleted_at IS NULL', ['default', $locale]) as $page) {
            $pages[$page['id']] = $page;
        }

        return $this->resolveLevel($items, $pages, $currentPath, $this->settings->homePath());
    }

    private function resolveLevel(array $items, array $pages, string $currentPath, string $homePath): array
    {
        $links = [];
        foreach ($items as $item) {
            $children = $this->resolveLevel($item['children'] ?? [], $pages, $currentPath, $homePath);
            $label = $item['label'] ?? '';
            if ('page' === $item['type']) {
                $page = $pages[$item['pageId']] ?? null;
                if (null === $page || null === $page['published_revision_id']) {
                    // Keep any resolvable children rather than dropping a whole branch.
                    array_push($links, ...$children);
                    continue;
                }
                $path = $this->settings->publicPath($page['path'], $homePath);
                $anchor = $item['anchor'] ?? '';
                $href = $path.('' === $anchor ? '' : '#'.$anchor);
                // An anchor link is never the current page on its own; it jumps inside one.
                $current = '' === $anchor && $page['path'] === $currentPath;
            } else {
                $href = $item['url'];
                $current = false;
            }
            if ('' === trim($label)) {
                continue;
            }
            $links[] = ['label' => $label, 'href' => $href, 'current' => $current, 'children' => $children];
        }

        return $links;
    }

    private function validate(array $items, int $depth = 1, int &$count = 0): void
    {
        if (!array_is_list($items)) {
            throw new InvalidMenu('Die Menüstruktur ist ungültig.');
        }
        if ([] !== $items && $depth > self::MAX_DEPTH) {
            throw new InvalidMenu(sprintf('Mehr als %d Menüebenen sind nicht vorgesehen.', self::MAX_DEPTH));
        }
        foreach ($items as $item) {
            if (++$count > self::MAX_ITEMS) {
                throw new InvalidMenu(sprintf('Ein Menü fasst höchstens %d Einträge.', self::MAX_ITEMS));
            }
            if (!is_array($item) || !is_string($item['label'] ?? null) || '' === trim($item['label']) || mb_strlen($item['label']) > 80) {
                throw new InvalidMenu('Jeder Eintrag braucht eine Beschriftung mit höchstens 80 Zeichen.');
            }
            if ('page' === ($item['type'] ?? null)) {
                if (!is_string($item['pageId'] ?? null) || 1 !== preg_match('/^[a-zA-Z0-9_-]{1,64}$/D', $item['pageId'])) {
                    throw new InvalidMenu('Für einen Seiteneintrag fehlt die Seite.');
                }
                $anchor = $item['anchor'] ?? '';
                if (!is_string($anchor) || ('' !== $anchor && 1 !== preg_match('/^[a-zA-Z][a-zA-Z0-9_-]{0,64}$/D', $anchor))) {
                    throw new InvalidMenu('Ein Sprungziel besteht aus Buchstaben, Ziffern, Bindestrich und Unterstrich und beginnt mit einem Buchstaben.');
                }
            } elseif ('url' === ($item['type'] ?? null)) {
                $this->url($item['url'] ?? null);
            } else {
                throw new InvalidMenu('Unbekannte Zielart.');
            }
            $this->validate($item['children'] ?? [], $depth + 1, $count);
        }
    }

    private function url(mixed $url): void
    {
        if (!is_string($url) || strlen($url) > 2048 || preg_match('/[\x00-\x20\\\\]/', $url)) {
            throw new InvalidMenu('Die Adresse ist leer, zu lang oder enthält unerlaubte Zeichen.');
        }
        // tel: and mailto: are real navigation targets on the pilot site, so they belong here.
        $allowed = str_starts_with($url, 'https://') && false !== filter_var($url, FILTER_VALIDATE_URL);
        $allowed = $allowed || (str_starts_with($url, '/') && !str_starts_with($url, '//'));
        $allowed = $allowed || 1 === preg_match('/^mailto:[^@\s]+@[^@\s]+$/D', $url);
        $allowed = $allowed || 1 === preg_match('/^tel:\+?[0-9 ()-]{3,32}$/D', $url);
        if (!$allowed) {
            throw new InvalidMenu('Erlaubt sind HTTPS-Adressen, lokale Pfade sowie mailto: und tel:.');
        }
    }
}