fix: Seahorse does not properly work on many Linux devices

- stop use of `flutter_secure_storage` for Linux in favor of unencrypted
  storage

Unlike many other platforms, many Linux distributions have built-in
support for FDE or home directory encryption. As long as
`flutter_secure_storage` makes FluffyChat useles on many Linuxes, this
seems to be the only solution until they stop using Seahorse.

Signed-off-by: TheOneWithTheBraid <the-one@with-the-braid.cf>

lib/pages/add_story/add_story.dart

@@ -39,11 +39,11 @@ class AddStoryController extends State<AddStoryPage> {
 
   bool get hasMedia => image != null || video != null;
 
-  void updateColors(String text) => hasMedia
+  void updateColors() => hasMedia
       ? null
       : setState(() {
-          backgroundColor = text.color;
-          backgroundColorDark = text.darkColor;
+          backgroundColor = controller.text.color;
+          backgroundColorDark = controller.text.darkColor;
         });
 
   void importMedia() async {

lib/pages/add_story/add_story_view.dart

@@ -98,7 +98,7 @@ class AddStoryView extends StatelessWidget {
                   color: Colors.white,
                   backgroundColor: !controller.hasMedia ? null : Colors.black,
                 ),
-                onChanged: controller.updateColors,
+                onEditingComplete: controller.updateColors,
                 decoration: InputDecoration(
                   border: InputBorder.none,
                   hintText: controller.hasMedia

lib/utils/matrix_sdk_extensions.dart/fluffybox_database.dart

@@ -40,6 +40,8 @@ class FlutterFluffyBoxDatabase extends FluffyBoxDatabase {
       final containsEncryptionKey =
           await secureStorage.containsKey(key: _cipherStorageKey);
       if (!containsEncryptionKey) {
+        // do not try to create a buggy secure storage for new Linux users
+        if (Platform.isLinux) throw MissingPluginException();
         final key = Hive.generateSecureKey();
         await secureStorage.write(
           key: _cipherStorageKey,

lib/utils/matrix_sdk_extensions.dart/flutter_matrix_hive_database.dart

@@ -31,7 +31,7 @@ class FlutterMatrixHiveStore extends FamedlySdkHiveDatabase {
     HiveCipher hiverCipher;
     try {
       // Workaround for secure storage is calling Platform.operatingSystem on web
-      if (kIsWeb) throw MissingPluginException();
+      if (kIsWeb || Platform.isLinux) throw MissingPluginException();
 
       const secureStorage = FlutterSecureStorage();
       final containsEncryptionKey =

lib/widgets/lock_screen.dart

@@ -4,6 +4,7 @@ import 'package:flutter_app_lock/flutter_app_lock.dart';
 import 'package:flutter_gen/gen_l10n/l10n.dart';
 import 'package:flutter_secure_storage/flutter_secure_storage.dart';
 import 'package:pin_code_text_field/pin_code_text_field.dart';
+import 'package:shared_preferences/shared_preferences.dart';
 
 import 'package:fluffychat/config/app_config.dart';
 import 'package:fluffychat/config/setting_keys.dart';
@@ -71,8 +72,12 @@ class _LockScreenState extends State<LockScreen> {
                 hasError: _wrongInput,
                 onDone: (String input) async {
                   if (input ==
-                      await const FlutterSecureStorage()
-                          .read(key: SettingKeys.appLockKey)) {
+                      await ([TargetPlatform.linux]
+                              .contains(Theme.of(context).platform)
+                          ? SharedPreferences.getInstance().then((prefs) =>
+                              prefs.getString(SettingKeys.appLockKey))
+                          : const FlutterSecureStorage()
+                              .read(key: SettingKeys.appLockKey))) {
                     AppLock.of(context).didUnlock();
                   } else {
                     _textEditingController.clear();

lib/widgets/matrix.dart

@@ -14,6 +14,7 @@ import 'package:http/http.dart' as http;
 import 'package:matrix/encryption.dart';
 import 'package:matrix/matrix.dart';
 import 'package:provider/provider.dart';
+import 'package:shared_preferences/shared_preferences.dart';
 import 'package:universal_html/html.dart' as html;
 import 'package:url_launcher/url_launcher.dart';
 import 'package:vrouter/vrouter.dart';
@@ -32,6 +33,8 @@ import '../utils/background_push.dart';
 import '../utils/famedlysdk_store.dart';
 import '../utils/platform_infos.dart';
 
+// import 'package:flutter_secure_storage/flutter_secure_storage.dart';
+
 class Matrix extends StatefulWidget {
   static const String callNamespace = 'chat.fluffy.jitsi_call';
 
@@ -407,8 +410,11 @@ class MatrixState extends State<Matrix> with WidgetsBindingObserver {
     // Display the app lock
     if (PlatformInfos.isMobile) {
       WidgetsBinding.instance.addPostFrameCallback((_) {
-        const FlutterSecureStorage()
-            .read(key: SettingKeys.appLockKey)
+        ([TargetPlatform.linux].contains(Theme.of(context).platform)
+                ? SharedPreferences.getInstance()
+                    .then((prefs) => prefs.getString(SettingKeys.appLockKey))
+                : const FlutterSecureStorage()
+                    .read(key: SettingKeys.appLockKey))
             .then((lock) {
           if (lock?.isNotEmpty ?? false) {
             AppLock.of(widget.context).enable();

pubspec.lock

@@ -1233,12 +1233,12 @@ packages:
     source: hosted
     version: "2.0.4"
   shared_preferences:
-    dependency: transitive
+    dependency: "direct main"
     description:
       name: shared_preferences
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.0.11"
+    version: "2.0.12"
   shared_preferences_android:
     dependency: transitive
     description:

pubspec.yaml

@@ -66,6 +66,7 @@ dependencies:
   scroll_to_index: ^2.1.0
   sentry: ^6.0.1
   share: ^2.0.4
+  shared_preferences: ^2.0.12
   slugify: ^2.0.0
   swipe_to_action: ^0.2.0
   uni_links: ^0.5.1