feat: regenerate message with different model

frontend/appflowy_flutter/lib/ai/ai.dart

@@ -2,6 +2,8 @@ export 'service/ai_entities.dart';
 export 'service/ai_prompt_input_bloc.dart';
 export 'service/appflowy_ai_service.dart';
 export 'service/error.dart';
+export 'service/ai_model_state_notifier.dart';
+export 'service/select_model_bloc.dart';
 export 'widgets/loading_indicator.dart';
 export 'widgets/prompt_input/action_buttons.dart';
 export 'widgets/prompt_input/desktop_prompt_text_field.dart';
@@ -13,4 +15,5 @@ export 'widgets/prompt_input/mentioned_page_text_span.dart';
 export 'widgets/prompt_input/predefined_format_buttons.dart';
 export 'widgets/prompt_input/select_sources_bottom_sheet.dart';
 export 'widgets/prompt_input/select_sources_menu.dart';
+export 'widgets/prompt_input/select_model_menu.dart';
 export 'widgets/prompt_input/send_button.dart';

frontend/appflowy_flutter/lib/ai/service/ai_entities.dart

@@ -4,6 +4,14 @@ import 'package:appflowy_backend/protobuf/flowy-ai/protobuf.dart';
 import 'package:easy_localization/easy_localization.dart';
 import 'package:equatable/equatable.dart';
 
+enum AiType {
+  cloud,
+  local;
+
+  bool get isCloud => this == cloud;
+  bool get isLocal => this == local;
+}
+
 class PredefinedFormat extends Equatable {
   const PredefinedFormat({
     required this.imageFormat,

frontend/appflowy_flutter/lib/ai/service/ai_model_state_notifier.dart

@@ -0,0 +1,172 @@
+import 'package:appflowy/ai/ai.dart';
+import 'package:appflowy/generated/locale_keys.g.dart';
+import 'package:appflowy/plugins/ai_chat/application/ai_model_switch_listener.dart';
+import 'package:appflowy/workspace/application/settings/ai/local_llm_listener.dart';
+import 'package:appflowy_backend/dispatch/dispatch.dart';
+import 'package:appflowy_backend/log.dart';
+import 'package:appflowy_backend/protobuf/flowy-ai/entities.pb.dart';
+import 'package:appflowy_result/appflowy_result.dart';
+import 'package:easy_localization/easy_localization.dart';
+import 'package:protobuf/protobuf.dart';
+import 'package:universal_platform/universal_platform.dart';
+
+typedef OnModelStateChangedCallback = void Function(AiType, bool, String);
+typedef OnAvailableModelsChangedCallback = void Function(
+  List<AIModelPB>,
+  AIModelPB?,
+);
+
+class AIModelStateNotifier {
+  AIModelStateNotifier({required this.objectId})
+      : _localAIListener =
+            UniversalPlatform.isDesktop ? LocalAIStateListener() : null,
+        _aiModelSwitchListener = AIModelSwitchListener(objectId: objectId) {
+    _startListening();
+    _init();
+  }
+
+  final String objectId;
+  final LocalAIStateListener? _localAIListener;
+  final AIModelSwitchListener _aiModelSwitchListener;
+  LocalAIPB? _localAIState;
+  AvailableModelsPB? _availableModels;
+
+  // callbacks
+  final List<OnModelStateChangedCallback> _stateChangedCallbacks = [];
+  final List<OnAvailableModelsChangedCallback>
+      _availableModelsChangedCallbacks = [];
+
+  void _startListening() {
+    if (UniversalPlatform.isDesktop) {
+      _localAIListener?.start(
+        stateCallback: (state) async {
+          _localAIState = state;
+          _notifyStateChanged();
+
+          if (state.state == RunningStatePB.Running ||
+              state.state == RunningStatePB.Stopped) {
+            await _loadAvailableModels();
+            _notifyAvailableModelsChanged();
+          }
+        },
+      );
+    }
+
+    _aiModelSwitchListener.start(
+      onUpdateSelectedModel: (model) async {
+        final updatedModels = _availableModels?.deepCopy()
+          ?..selectedModel = model;
+        _availableModels = updatedModels;
+        _notifyAvailableModelsChanged();
+
+        if (model.isLocal && UniversalPlatform.isDesktop) {
+          await _loadLocalAiState();
+        }
+        _notifyStateChanged();
+      },
+    );
+  }
+
+  void _init() async {
+    await Future.wait([_loadLocalAiState(), _loadAvailableModels()]);
+    _notifyStateChanged();
+    _notifyAvailableModelsChanged();
+  }
+
+  void addListener({
+    OnModelStateChangedCallback? onStateChanged,
+    OnAvailableModelsChangedCallback? onAvailableModelsChanged,
+  }) {
+    if (onStateChanged != null) {
+      _stateChangedCallbacks.add(onStateChanged);
+    }
+    if (onAvailableModelsChanged != null) {
+      _availableModelsChangedCallbacks.add(onAvailableModelsChanged);
+    }
+  }
+
+  void removeListener({
+    OnModelStateChangedCallback? onStateChanged,
+    OnAvailableModelsChangedCallback? onAvailableModelsChanged,
+  }) {
+    if (onStateChanged != null) {
+      _stateChangedCallbacks.remove(onStateChanged);
+    }
+    if (onAvailableModelsChanged != null) {
+      _availableModelsChangedCallbacks.remove(onAvailableModelsChanged);
+    }
+  }
+
+  Future<void> dispose() async {
+    _stateChangedCallbacks.clear();
+    _availableModelsChangedCallbacks.clear();
+    await _localAIListener?.stop();
+    await _aiModelSwitchListener.stop();
+  }
+
+  (AiType, String, bool) getState() {
+    if (UniversalPlatform.isMobile) {
+      return (AiType.cloud, LocaleKeys.chat_inputMessageHint.tr(), true);
+    }
+
+    final availableModels = _availableModels;
+    final localAiState = _localAIState;
+
+    if (availableModels == null) {
+      Log.warn("No available models");
+      return (AiType.cloud, LocaleKeys.chat_inputMessageHint.tr(), true);
+    }
+    if (localAiState == null) {
+      Log.warn("Cannot get local AI state");
+      return (AiType.cloud, LocaleKeys.chat_inputMessageHint.tr(), true);
+    }
+
+    if (!availableModels.selectedModel.isLocal) {
+      return (AiType.cloud, LocaleKeys.chat_inputMessageHint.tr(), true);
+    }
+
+    final editable = localAiState.state == RunningStatePB.Running;
+    final hintText = editable
+        ? LocaleKeys.chat_inputLocalAIMessageHint.tr()
+        : LocaleKeys.settings_aiPage_keys_localAIInitializing.tr();
+
+    return (AiType.local, hintText, editable);
+  }
+
+  (List<AIModelPB>, AIModelPB?) getAvailableModels() {
+    final availableModels = _availableModels;
+    if (availableModels == null) {
+      return ([], null);
+    }
+    return (availableModels.models, availableModels.selectedModel);
+  }
+
+  void _notifyAvailableModelsChanged() {
+    final (models, selectedModel) = getAvailableModels();
+    for (final callback in _availableModelsChangedCallbacks) {
+      callback(models, selectedModel);
+    }
+  }
+
+  void _notifyStateChanged() {
+    final (type, hintText, isEditable) = getState();
+    for (final callback in _stateChangedCallbacks) {
+      callback(type, isEditable, hintText);
+    }
+  }
+
+  Future<void> _loadAvailableModels() {
+    final payload = AvailableModelsQueryPB(source: objectId);
+    return AIEventGetAvailableModels(payload).send().fold(
+          (models) => _availableModels = models,
+          (err) => Log.error("Failed to get available models: $err"),
+        );
+  }
+
+  Future<void> _loadLocalAiState() {
+    return AIEventGetLocalAIState().send().fold(
+          (localAIState) => _localAIState = localAIState,
+          (error) => Log.error("Failed to get local AI state: $error"),
+        );
+  }
+}