addon store initial

apps/weblibre/lib/features/addons/utils/addon_html.dart

@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2024-2026 Fabian Freund.
+ *
+ * This file is part of WebLibre
+ * (see https://weblibre.eu).
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+import 'package:flutter_mozilla_components/flutter_mozilla_components.dart';
+
+/// AMO descriptions mix raw HTML tags with entity-escaped ones
+/// (e.g. `&lt;b&gt;not&lt;/b&gt;` next to `<ul><li>…</li></ul>`). DOMParser
+/// would decode the entities to literal text characters, so turndown would
+/// emit them verbatim. Decode entities once here so the escaped tags become
+/// real markup before the extension runs.
+String _decodeHtmlEntities(String input) {
+  return input
+      .replaceAll('&lt;', '<')
+      .replaceAll('&gt;', '>')
+      .replaceAll('&quot;', '"')
+      .replaceAll('&#39;', "'")
+      .replaceAll('&apos;', "'")
+      .replaceAll('&nbsp;', ' ')
+      .replaceAll('&amp;', '&');
+}
+
+Future<String> turndownAddonHtml(String description) async {
+  if (description.isEmpty) return '';
+
+  final results = await GeckoBrowserExtensionService.turndownHtml([
+    _decodeHtmlEntities(description),
+  ], timeout: const Duration(seconds: 3));
+
+  final markdown = results.firstOrNull?.markdown?.trim();
+  return (markdown == null || markdown.isEmpty) ? description : markdown;
+}