fix: Punycode-encode unicode domains for platforms which can't handle them

assets/l10n/intl_en.arb

@@ -11,6 +11,13 @@
     "type": "text",
     "placeholders": {}
   },
+  "cantOpenUri": "Can't open the URI {uri}",
+  "@cantOpenUri": {
+    "type": "text",
+    "placeholders": {
+      "uri": {}
+    }
+  },
   "chats": "Chats",
   "@chats": {
     "type": "text",

lib/utils/url_launcher.dart

@@ -7,6 +7,8 @@ import 'package:fluffychat/config/app_config.dart';
 import 'package:flutter/material.dart';
 import 'package:url_launcher/url_launcher.dart';
 import 'package:vrouter/vrouter.dart';
+import 'package:punycode/punycode.dart';
+import 'package:flutter_gen/gen_l10n/l10n.dart';
 
 class UrlLauncher {
   final String url;
@@ -19,7 +21,34 @@ class UrlLauncher {
         url.toLowerCase().startsWith(AppConfig.schemePrefix)) {
       return openMatrixToUrl();
     }
-    launch(url);
+    final uri = Uri.tryParse(url);
+    if (uri == null) {
+      // we can't open this thing
+      ScaffoldMessenger.of(context).showSnackBar(
+          SnackBar(content: Text(L10n.of(context).cantOpenUri(url))));
+      return;
+    }
+    if (!{'https', 'http'}.contains(uri.scheme)) {
+      // just launch non-https / non-http uris directly
+      launch(url);
+      return;
+    }
+    if (uri.host == null) {
+      ScaffoldMessenger.of(context).showSnackBar(
+          SnackBar(content: Text(L10n.of(context).cantOpenUri(url))));
+      return;
+    }
+    // okay, we have either an http or an https URI.
+    // As some platforms have issues with opening unicode URLs, we are going to help
+    // them out by punycode-encoding them for them ourself.
+    final newHost = uri.host.split('.').map((hostPartEncoded) {
+      final hostPart = Uri.decodeComponent(hostPartEncoded);
+      final hostPartPunycode = punycodeEncode(hostPart);
+      return hostPartPunycode != hostPart + '-'
+          ? 'xn--$hostPartPunycode'
+          : hostPart;
+    }).join('.');
+    launch(uri.replace(host: newHost).toString());
   }
 
   void openMatrixToUrl() async {

pubspec.lock

@@ -670,12 +670,12 @@ packages:
     source: hosted
     version: "0.3.5"
   matrix_link_text:
-    dependency: transitive
+    dependency: "direct main"
     description:
       name: matrix_link_text
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.4.1"
+    version: "0.4.2"
   meta:
     dependency: transitive
     description:
@@ -937,6 +937,13 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "2.0.0"
+  punycode:
+    dependency: "direct main"
+    description:
+      name: punycode
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.0.0"
   quiver:
     dependency: transitive
     description:

pubspec.yaml

@@ -47,6 +47,7 @@ dependencies:
   localstorage: ^4.0.0+1
   lottie: ^1.1.0
   matrix: ^0.1.11
+  matrix_link_text: ^0.4.2
   native_imaging:
     git: https://gitlab.com/famedly/libraries/native_imaging.git
   open_noti_settings: ^0.2.0
@@ -55,6 +56,7 @@ dependencies:
   permission_handler: ^8.1.4+1
   pin_code_text_field: ^1.8.0
   provider: ^5.0.0
+  punycode: ^1.0.0
   receive_sharing_intent: ^1.4.5
   record: ^3.0.0
   scroll_to_index: ^2.0.0