chore: restructure the Flutter app code (#298)

* Collect all custom reusable widgets in the `widgets` module
* Group user features in `user` module
* Split settings into `user` and `developer` modules
* Rename conversation list pane to conversation list
* Move core client and extension to `core` module
* Split conversation pane into `converation_details` and `message_list`
* Move styles into `theme` module
* Screens now wrap screen views with required providers
* Bundle utilities in `util` module

Author: boxdot

app/README.md

@@ -8,3 +8,23 @@ SPDX-License-Identifier: AGPL-3.0-or-later
 
 A GUI client for OpenMLS
 
+## Code organization
+
+The app code is organized in the following way:
+
+- Each feature is a separate module in the `lib` directory.
+- Each module in the `lib` exports all its public APIs in the dart file with the
+same name as the module. Other modules should import this dart file.
+- Reusable widgets are in the `widgets` module.
+- All styles and theme related code in the `theme` module.
+- The module `core` contains the Rust generated code and extensions.
+
+### Naming conventions
+
+- `View` is a pure widget without any providers.
+- `Container` wraps a `View` and creates all required providers.
+- `ScreenView` is a root widget in the navigation without any providers.
+- `Screen` wraps a `ScreenView` and creates all required providers. This is the
+  actual class used in the navigation stack.
+- `Pane` is a widget that is used in large screen layout and divide the screen into
+  smaller sections.

app/lib/app.dart

@@ -8,11 +8,10 @@ import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:logging/logging.dart';
 import 'package:permission_handler/permission_handler.dart';
-import 'package:prototype/core_client.dart';
+import 'package:prototype/core/core.dart';
 import 'package:prototype/navigation/navigation.dart';
-import 'package:prototype/platform.dart';
-import 'package:prototype/loadable_user_cubit.dart';
-import 'package:prototype/user_cubit.dart';
+import 'package:prototype/util/platform.dart';
+import 'package:prototype/user/user.dart';
 import 'package:provider/provider.dart';
 
 import 'registration/registration.dart';

app/lib/conversation_pane/conversation_details/add_members_cubit.dart renamed to app/lib/conversation_details/add_members_cubit.dart

@@ -4,15 +4,15 @@
 
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
-import 'package:prototype/elements.dart';
 import 'package:prototype/navigation/navigation.dart';
-import 'package:prototype/styles.dart';
-import 'package:prototype/user_cubit.dart';
+import 'package:prototype/theme/theme.dart';
+import 'package:prototype/user/user.dart';
+import 'package:prototype/widgets/widgets.dart';
 
 import 'add_members_cubit.dart';
 
-class AddMembers extends StatelessWidget {
-  const AddMembers({super.key});
+class AddMembersScreen extends StatelessWidget {
+  const AddMembersScreen({super.key});
 
   @override
   Widget build(BuildContext context) {
@@ -21,13 +21,13 @@ class AddMembers extends StatelessWidget {
         final userCubit = context.read<UserCubit>();
         return AddMembersCubit()..loadContacts(userCubit.contacts);
       },
-      child: const AddMembersView(),
+      child: const AddMembersScreenView(),
     );
   }
 }
 
-class AddMembersView extends StatelessWidget {
-  const AddMembersView({super.key});
+class AddMembersScreenView extends StatelessWidget {
+  const AddMembersScreenView({super.key});
 
   @override
   Widget build(BuildContext context) {
@@ -43,7 +43,7 @@ class AddMembersView extends StatelessWidget {
         backgroundColor: Colors.white,
         elevation: 0,
         scrolledUnderElevation: 0,
-        leading: appBarBackButton(context),
+        leading: const AppBarBackButton(),
         title: const Text("Add members"),
       ),
       body: Padding(

app/lib/conversation_pane/conversation_details/add_members.dart renamed to app/lib/conversation_details/add_members_screen.dart

@@ -3,10 +3,9 @@
 // SPDX-License-Identifier: AGPL-3.0-or-later
 
 import 'package:flutter/material.dart';
-import 'package:prototype/core_extension.dart';
-import 'package:prototype/elements.dart';
-import 'package:prototype/styles.dart';
+import 'package:prototype/core/core.dart';
 import 'package:prototype/theme/theme.dart';
+import 'package:prototype/widgets/widgets.dart';
 import 'package:provider/provider.dart';
 
 import 'conversation_details_cubit.dart';

app/lib/conversation_pane/conversation_details/connection_details.dart renamed to app/lib/conversation_details/connection_details.dart

@@ -0,0 +1,12 @@
+// SPDX-FileCopyrightText: 2025 Phoenix R&D GmbH <[email protected]>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+/// The application user features
+library;
+
+export 'add_members_screen.dart';
+export 'conversation_details_cubit.dart';
+export 'conversation_details_screen.dart';
+export 'conversation_screen.dart';
+export 'member_details_screen.dart';

app/lib/conversation_details/conversation_details.dart

@@ -7,7 +7,7 @@ import 'dart:typed_data';
 
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:prototype/core/core.dart';
-import 'package:prototype/user_cubit.dart';
+import 'package:prototype/user/user.dart';
 
 class ConversationDetailsCubit
     extends StateStreamableSource<ConversationDetailsState> {

app/lib/conversation_pane/conversation_details/conversation_details_cubit.dart renamed to app/lib/conversation_details/conversation_details_cubit.dart

@@ -5,18 +5,18 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:prototype/core/core.dart';
-import 'package:prototype/elements.dart';
 import 'package:prototype/navigation/navigation.dart';
+import 'package:prototype/widgets/widgets.dart';
 
 import 'connection_details.dart';
 import 'conversation_details_cubit.dart';
 import 'group_details.dart';
 
-/// Container for [ConversationDetailsScreen]
+/// Container for [ConversationDetailsScreenView]
 ///
 /// Wraps the screen with required providers.
-class ConversationDetailsContainer extends StatelessWidget {
-  const ConversationDetailsContainer({super.key});
+class ConversationDetailsScreen extends StatelessWidget {
+  const ConversationDetailsScreen({super.key});
 
   @override
   Widget build(BuildContext context) {
@@ -32,14 +32,14 @@ class ConversationDetailsContainer extends StatelessWidget {
         userCubit: context.read(),
         conversationId: conversationId,
       ),
-      child: ConversationDetailsScreen(),
+      child: ConversationDetailsScreenView(),
     );
   }
 }
 
 /// Screen that shows details of a conversation
-class ConversationDetailsScreen extends StatelessWidget {
-  const ConversationDetailsScreen({super.key});
+class ConversationDetailsScreenView extends StatelessWidget {
+  const ConversationDetailsScreenView({super.key});
 
   @override
   Widget build(BuildContext context) {
@@ -51,7 +51,7 @@ class ConversationDetailsScreen extends StatelessWidget {
         backgroundColor: Colors.white,
         elevation: 0,
         scrolledUnderElevation: 0,
-        leading: appBarBackButton(context),
+        leading: const AppBarBackButton(),
         title: const Text("Details"),
       ),
       body: switch (conversationType) {

app/lib/conversation_pane/conversation_details/conversation_details.dart renamed to app/lib/conversation_details/conversation_details_screen.dart

@@ -4,17 +4,16 @@
 
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
-import 'package:prototype/core_extension.dart';
-import 'package:prototype/elements.dart';
+import 'package:prototype/core/core.dart';
+import 'package:prototype/message_list/message_list.dart';
 import 'package:prototype/navigation/navigation.dart';
-import 'package:prototype/styles.dart';
 import 'package:prototype/theme/theme.dart';
-import 'conversation_content/message_list_view.dart';
-import 'conversation_details/conversation_details_cubit.dart';
-import 'message_composer.dart';
+import 'package:prototype/widgets/widgets.dart';
 
-class ConversationPaneContainer extends StatelessWidget {
-  const ConversationPaneContainer({super.key});
+import 'conversation_details_cubit.dart';
+
+class ConversationScreen extends StatelessWidget {
+  const ConversationScreen({super.key});
 
   @override
   Widget build(BuildContext context) {
@@ -32,7 +31,7 @@ class ConversationPaneContainer extends StatelessWidget {
         userCubit: context.read(),
         conversationId: conversationId,
       ),
-      child: const ConversationPane(),
+      child: const ConversationScreenView(),
     );
   }
 }
@@ -53,8 +52,8 @@ class _EmptyConversationPane extends StatelessWidget {
   }
 }
 
-class ConversationPane extends StatelessWidget {
-  const ConversationPane({super.key});
+class ConversationScreenView extends StatelessWidget {
+  const ConversationScreenView({super.key});
 
   @override
   Widget build(BuildContext context) {
@@ -89,8 +88,9 @@ class ConversationPane extends StatelessWidget {
             elevation: 0,
             // Applying blur effect
             flexibleSpace: FrostedGlass(
-                color: Colors.white,
-                height: kToolbarHeight + MediaQuery.of(context).padding.top),
+              color: Colors.white,
+              height: kToolbarHeight + MediaQuery.of(context).padding.top,
+            ),
           ),
         ),
       ]),

app/lib/conversation_pane/conversation_pane.dart renamed to app/lib/conversation_details/conversation_screen.dart

@@ -4,12 +4,11 @@
 
 import 'package:flutter/material.dart';
 import 'package:image_picker/image_picker.dart';
-import 'package:prototype/core_extension.dart';
-import 'package:prototype/elements.dart';
+import 'package:prototype/core/core.dart';
 import 'package:prototype/navigation/navigation.dart';
-import 'package:prototype/styles.dart';
 import 'package:prototype/theme/theme.dart';
-import 'package:prototype/user_cubit.dart';
+import 'package:prototype/user/user.dart';
+import 'package:prototype/widgets/widgets.dart';
 import 'package:provider/provider.dart';
 
 import 'conversation_details_cubit.dart';