Add generation status and cancel control

SovereignAI-Starter/flutter_app/test/chat_cubit_test.dart

@@ -1,5 +1,6 @@
-import 'package:flutter_test/flutter_test.dart';
+import 'dart:async';
 
+import 'package:flutter_test/flutter_test.dart';
 import 'package:flutter_app/core/network/api_repository.dart';
 import 'package:flutter_app/features/chat/presentation/cubit/chat_cubit.dart';
 import 'package:flutter_app/features/chat/presentation/cubit/chat_state.dart';
@@ -28,10 +29,40 @@ class _VersionTestApi extends ApiRepository {
   }
 
   @override
-  Stream<String> completeStream(
-    List<ChatMessage> messages, {
-    String? model,
-  }) => Stream<String>.fromIterable(responses.removeAt(0));
+  Stream<String> completeStream(List<ChatMessage> messages, {String? model}) =>
+      Stream<String>.fromIterable(responses.removeAt(0));
+}
+
+class _CancellableTestApi extends _VersionTestApi {
+  final controller = StreamController<String>();
+  var cancelled = false;
+  final storedConversation = SavedConversation(
+    id: 'conversation',
+    title: 'سؤال قديم',
+    updatedAt: DateTime.utc(2026),
+    messages: const [
+      ChatMessage('سؤال قديم', fromUser: true),
+      ChatMessage(
+        'إجابة محفوظة',
+        fromUser: false,
+        answerVersions: ['إجابة محفوظة'],
+      ),
+    ],
+  );
+
+  @override
+  Future<SavedConversation> getConversation(String id) async =>
+      storedConversation;
+
+  @override
+  Stream<String> completeStream(List<ChatMessage> messages, {String? model}) =>
+      controller.stream;
+
+  @override
+  void cancelActiveRequest() {
+    cancelled = true;
+    controller.close();
+  }
 }
 
 void main() {
@@ -42,18 +73,75 @@ void main() {
 
     await cubit.send('ما معنى API؟');
     expect(cubit.state.messages.last.answerVersions, ['الجواب الأول']);
+    expect(cubit.state.modelStatus, ModelConnectionStatus.connected);
+    expect(cubit.state.requestStatus, RequestStatus.completed);
+    expect(cubit.state.lastResponseDuration, isNotNull);
 
     await cubit.regenerateLastAnswer();
     expect(cubit.state.messages.last.text, 'الجواب الثاني');
-    expect(cubit.state.messages.last.answerVersions, ['الجواب الأول', 'الجواب الثاني']);
+    expect(cubit.state.messages.last.answerVersions, [
+      'الجواب الأول',
+      'الجواب الثاني',
+    ]);
     expect(cubit.state.messages.last.selectedVersion, 1);
 
     await cubit.selectAnswerVersion(1, 0);
     expect(cubit.state.messages.last.text, 'الجواب الأول');
     expect(cubit.state.messages.last.selectedVersion, 0);
-    expect(api.lastSaved?.messages.last.answerVersions, ['الجواب الأول', 'الجواب الثاني']);
+    expect(api.lastSaved?.messages.last.answerVersions, [
+      'الجواب الأول',
+      'الجواب الثاني',
+    ]);
     expect(api.lastSaved?.messages.last.selectedVersion, 0);
 
     await cubit.close();
   });
+
+  test(
+    'cancelling generation preserves partial text and records duration',
+    () async {
+      final api = _CancellableTestApi();
+      final cubit = ChatCubit(api);
+      await Future<void>.delayed(Duration.zero);
+
+      final send = cubit.send('اكتب فقرة قصيرة');
+      await Future<void>.delayed(const Duration(milliseconds: 20));
+      api.controller.add('بداية الإجابة');
+      await Future<void>.delayed(Duration.zero);
+      await cubit.cancelGeneration();
+      await send;
+
+      expect(api.cancelled, isTrue);
+      expect(cubit.state.isSending, isFalse);
+      expect(cubit.state.requestStatus, RequestStatus.cancelled);
+      expect(cubit.state.messages.last.text, 'بداية الإجابة');
+      expect(cubit.state.lastResponseDuration, isNotNull);
+      expect(api.lastSaved?.messages.last.text, 'بداية الإجابة');
+
+      await cubit.close();
+      await api.controller.close();
+    },
+  );
+
+  test(
+    'cancelling regeneration before its first token keeps saved answer',
+    () async {
+      final api = _CancellableTestApi();
+      final cubit = ChatCubit(api);
+      await Future<void>.delayed(Duration.zero);
+      await cubit.openConversation(api.storedConversation);
+
+      final regeneration = cubit.regenerateLastAnswer();
+      await Future<void>.delayed(const Duration(milliseconds: 20));
+      await cubit.cancelGeneration();
+      await regeneration;
+
+      expect(cubit.state.messages.last.text, 'إجابة محفوظة');
+      expect(api.lastSaved?.messages.last.text, 'إجابة محفوظة');
+      expect(cubit.state.requestStatus, RequestStatus.cancelled);
+
+      await cubit.close();
+      await api.controller.close();
+    },
+  );
 }