use global state to memorize assistant options

app/lib/features/search_browser/domain/providers.dart

@@ -4,6 +4,7 @@ import 'dart:async';
 
 import 'package:bang_navigator/features/bangs/data/models/bang_data.dart';
 import 'package:bang_navigator/features/bangs/domain/repositories/data.dart';
+import 'package:bang_navigator/features/search_browser/domain/entities/modes.dart';
 import 'package:bang_navigator/features/search_browser/domain/entities/sheet.dart';
 import 'package:bang_navigator/features/search_browser/domain/services/create_tab.dart';
 import 'package:flutter/widgets.dart';
@@ -91,3 +92,39 @@ Stream<BangData?> selectedBangData(SelectedBangDataRef ref, {String? domain}) {
       ref.watch(selectedBangTriggerProvider(domain: domain));
   return repository.watchBang(selectedBangTrigger);
 }
+
+@Riverpod(keepAlive: true)
+class LastUsedAssistantMode extends _$LastUsedAssistantMode {
+  void update(AssistantMode mode) {
+    state = mode;
+  }
+
+  @override
+  AssistantMode build() {
+    return AssistantMode.research;
+  }
+}
+
+@Riverpod(keepAlive: true)
+class ActiveResearchVariant extends _$ActiveResearchVariant {
+  void update(ResearchVariant mode) {
+    state = mode;
+  }
+
+  @override
+  ResearchVariant build() {
+    return ResearchVariant.expert;
+  }
+}
+
+@Riverpod(keepAlive: true)
+class ActiveChatModel extends _$ActiveChatModel {
+  void update(ChatModel model) {
+    state = model;
+  }
+
+  @override
+  ChatModel build() {
+    return ChatModel.gpt4o;
+  }
+}

app/lib/features/search_browser/domain/providers.g.dart

@@ -345,5 +345,56 @@ class _SelectedBangTriggerProviderElement
   @override
   String? get domain => (origin as SelectedBangTriggerProvider).domain;
 }
+
+String _$lastUsedAssistantModeHash() =>
+    r'1255a2754a3ea5ea058d110fd9743897fe103a69';
+
+/// See also [LastUsedAssistantMode].
+@ProviderFor(LastUsedAssistantMode)
+final lastUsedAssistantModeProvider =
+    NotifierProvider<LastUsedAssistantMode, AssistantMode>.internal(
+  LastUsedAssistantMode.new,
+  name: r'lastUsedAssistantModeProvider',
+  debugGetCreateSourceHash: const bool.fromEnvironment('dart.vm.product')
+      ? null
+      : _$lastUsedAssistantModeHash,
+  dependencies: null,
+  allTransitiveDependencies: null,
+);
+
+typedef _$LastUsedAssistantMode = Notifier<AssistantMode>;
+String _$activeResearchVariantHash() =>
+    r'8c65a3f5ead6cc4f9e2af85b607b7a49b0764ee3';
+
+/// See also [ActiveResearchVariant].
+@ProviderFor(ActiveResearchVariant)
+final activeResearchVariantProvider =
+    NotifierProvider<ActiveResearchVariant, ResearchVariant>.internal(
+  ActiveResearchVariant.new,
+  name: r'activeResearchVariantProvider',
+  debugGetCreateSourceHash: const bool.fromEnvironment('dart.vm.product')
+      ? null
+      : _$activeResearchVariantHash,
+  dependencies: null,
+  allTransitiveDependencies: null,
+);
+
+typedef _$ActiveResearchVariant = Notifier<ResearchVariant>;
+String _$activeChatModelHash() => r'675f406af8b4aa92699d59e37b5805a81d03a799';
+
+/// See also [ActiveChatModel].
+@ProviderFor(ActiveChatModel)
+final activeChatModelProvider =
+    NotifierProvider<ActiveChatModel, ChatModel>.internal(
+  ActiveChatModel.new,
+  name: r'activeChatModelProvider',
+  debugGetCreateSourceHash: const bool.fromEnvironment('dart.vm.product')
+      ? null
+      : _$activeChatModelHash,
+  dependencies: null,
+  allTransitiveDependencies: null,
+);
+
+typedef _$ActiveChatModel = Notifier<ChatModel>;
 // ignore_for_file: type=lint
 // ignore_for_file: subtype_of_sealed_class, invalid_use_of_internal_member, invalid_use_of_visible_for_testing_member

app/lib/features/search_browser/presentation/widgets/tabs/assistant_tab.dart

@@ -1,4 +1,5 @@
 import 'package:bang_navigator/features/search_browser/domain/entities/modes.dart';
+import 'package:bang_navigator/features/search_browser/domain/providers.dart';
 import 'package:bang_navigator/features/search_browser/presentation/widgets/sheets/shared_content_sheet.dart';
 import 'package:bang_navigator/features/search_browser/presentation/widgets/speech_to_text_button.dart';
 import 'package:bang_navigator/features/search_browser/utils/url_builder.dart'
@@ -29,20 +30,30 @@ class AssistantTab extends HookConsumerWidget {
           .select((value) => value.valueOrNull?.incognitoMode ?? false),
     );
 
+    final researchVariant = ref.watch(activeResearchVariantProvider);
+    final chatModel = ref.watch(activeChatModelProvider);
+
     useAutomaticKeepAlive();
 
     final formKey = useMemoized(() => GlobalKey<FormState>());
     final textController =
         useTextEditingController(text: sharedContent?.toString());
 
-    final tabController =
+    final tabController = useTabController(
-        useTabController(initialLength: AssistantMode.values.length);
+      initialLength: AssistantMode.values.length,
+      initialIndex: ref.read(lastUsedAssistantModeProvider).index,
+    );
     final pageController = usePageController(initialPage: tabController.index);
 
-    useSyncPageWithTab(tabController, pageController);
+    useSyncPageWithTab(
-
+      tabController,
-    final researchVariant = useState(ResearchVariant.expert);
+      pageController,
-    final chatModel = useState(ChatModel.gpt4o);
+      onIndexChanged: (index) {
+        ref
+            .read(lastUsedAssistantModeProvider.notifier)
+            .update(AssistantMode.values[index]);
+      },
+    );
 
     return Form(
       key: formKey,
@@ -92,9 +103,11 @@ class AssistantTab extends HookConsumerWidget {
                         label: Text('Fast'),
                       ),
                     ],
-                    selected: {researchVariant.value},
+                    selected: {researchVariant},
                     onSelectionChanged: (value) {
-                      researchVariant.value = value.first;
+                      ref
+                          .read(activeResearchVariantProvider.notifier)
+                          .update(value.first);
                     },
                   ),
                 ],
@@ -107,7 +120,7 @@ class AssistantTab extends HookConsumerWidget {
                     height: 12,
                   ),
                   DropdownMenu<ChatModel>(
-                    initialSelection: chatModel.value,
+                    initialSelection: chatModel,
                     expandedInsets: EdgeInsets.zero,
                     label: const Text('Model'),
                     inputDecorationTheme: const InputDecorationTheme(),
@@ -120,7 +133,7 @@ class AssistantTab extends HookConsumerWidget {
                         )
                         .toList(),
                     onSelected: (value) {
-                      chatModel.value = value!;
+                      ref.read(activeChatModelProvider.notifier).update(value!);
                     },
                   ),
                 ],
@@ -165,8 +178,8 @@ class AssistantTab extends HookConsumerWidget {
                     uri_builder.assistantUri(
                       prompt: textController.text,
                       assistantMode: AssistantMode.values[tabController.index],
-                      researchVariant: researchVariant.value,
+                      researchVariant: researchVariant,
-                      chatModel: chatModel.value,
+                      chatModel: chatModel,
                     ),
                   );
                 }

app/lib/presentation/hooks/sync_page_tab.dart

@@ -3,8 +3,9 @@ import 'package:flutter_hooks/flutter_hooks.dart';
 
 void useSyncPageWithTab(
   TabController tabController,
-  PageController pageController,
+  PageController pageController, {
-) {
+  void Function(int index)? onIndexChanged,
+}) {
   useEffect(
     () {
       Future<void> syncPage() async {
@@ -13,11 +14,15 @@ void useSyncPageWithTab(
           curve: Curves.linear,
           duration: const Duration(milliseconds: 300),
         );
+        onIndexChanged?.call(tabController.index);
       }
 
       void syncTab() {
         if (!tabController.indexIsChanging) {
-          tabController.animateTo(pageController.page!.round());
+          final index = pageController.page!.round();
+
+          tabController.animateTo(index);
+          onIndexChanged?.call(index);
         }
       }