feat: surface device and scene load errors

lib/providers/providers.dart

@@ -503,7 +503,8 @@ class GroupsNotifier extends Notifier<List<dynamic>> {
       await _api.controlGroup(id, {'state': on});
     } catch (e) {
       _lockUntil.remove(id);
-      refresh();
+      await refresh();
+      rethrow;
     }
   }
 
@@ -540,7 +541,8 @@ class GroupsNotifier extends Notifier<List<dynamic>> {
       await _api.controlGroup(id, {'scene': scene});
     } catch (e) {
       _lockUntil.remove(id);
-      refresh();
+      await refresh();
+      rethrow;
     }
   }
 
@@ -558,64 +560,92 @@ class GroupsNotifier extends Notifier<List<dynamic>> {
 
 // ─── Устройства (для создания групп) ─────────────────────────
 
-final devicesProvider = NotifierProvider<DevicesNotifier, List<dynamic>>(
+final devicesProvider =
+    NotifierProvider<DevicesNotifier, LoadState<List<dynamic>>>(
       () => DevicesNotifier(),
-);
+    );
 
-class DevicesNotifier extends Notifier<List<dynamic>> {
+class DevicesNotifier extends Notifier<LoadState<List<dynamic>>> {
   @override
-  List<dynamic> build() => [];
+  LoadState<List<dynamic>> build() => const LoadState.idle(<dynamic>[]);
 
   /// Загрузить список устройств из текущего дома
   Future<void> load() async {
+    state = LoadState.loading(state.data);
     try {
       final api = ref.read(apiProvider);
       final res = await api.getDevices();
-      if (res.data is List) {
+      final data = res.data;
-        state = res.data;
+      late final List<dynamic> devices;
-      } else if (res.data is Map) {
+      if (data is List) {
-        state =
+        devices = List<dynamic>.from(data);
-            res.data['data'] ?? res.data['devices'] ?? res.data.values.toList();
+      } else if (data is Map) {
+        final value = data['data'] ?? data['devices'] ?? data.values.toList();
+        if (value is! List) {
+          throw FormatException('devices должен быть списком устройств');
         }
+        devices = List<dynamic>.from(value);
+      } else {
+        throw FormatException('devices должен быть списком устройств');
+      }
+
+      state = devices.isEmpty
+          ? LoadState.empty(devices)
+          : LoadState.data(devices);
     } catch (e) {
-      debugPrint("Ошибка загрузки устройств: $e");
+      state = LoadState.error(state.data, describeLoadError(e));
     }
   }
 }
 
 // ─── Сцены ───────────────────────────────────────────────────
 
-final scenesProvider = NotifierProvider<ScenesNotifier, List<dynamic>>(
+final scenesProvider =
+    NotifierProvider<ScenesNotifier, LoadState<List<dynamic>>>(
       () => ScenesNotifier(),
-);
+    );
 
-class ScenesNotifier extends Notifier<List<dynamic>> {
+class ScenesNotifier extends Notifier<LoadState<List<dynamic>>> {
   @override
-  List<dynamic> build() => [];
+  LoadState<List<dynamic>> build() => const LoadState.idle(<dynamic>[]);
 
   Future<void> load() async {
+    state = LoadState.loading(state.data);
     try {
       final api = ref.read(apiProvider);
       final res = await api.getScenes();
       final data = res.data;
+      late final List<dynamic> scenes;
       if (data is List) {
-        state = data;
+        scenes = List<dynamic>.from(data);
       } else if (data is Map) {
         // Бэкенд может вернуть {scene_id: "Scene Name", ...}
         // или {data: [...]} или {scenes: [...]}
-        if (data.containsKey('data') && data['data'] is List) {
+        if (data.containsKey('data')) {
-          state = data['data'];
+          final value = data['data'];
-        } else if (data.containsKey('scenes') && data['scenes'] is List) {
+          if (value is! List) {
-          state = data['scenes'];
+            throw FormatException('scenes.data должен быть списком сцен');
+          }
+          scenes = List<dynamic>.from(value);
+        } else if (data.containsKey('scenes')) {
+          final value = data['scenes'];
+          if (value is! List) {
+            throw FormatException('scenes должен быть списком сцен');
+          }
+          scenes = List<dynamic>.from(value);
         } else {
           // Map вида {id: name} -- преобразуем в список
-          state = data.entries
+          scenes = data.entries
               .map((e) => {'id': e.key.toString(), 'name': e.value.toString()})
               .toList();
         }
+      } else {
+        throw FormatException('scenes должен быть списком сцен');
       }
+
+      state = scenes.isEmpty ? LoadState.empty(scenes) : LoadState.data(scenes);
     } catch (e) {
-      debugPrint("Ошибка загрузки сцен: $e");
+      state = LoadState.error(state.data, describeLoadError(e));
     }
   }
 }

lib/screens/group_edit_screen.dart

@@ -1,6 +1,9 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
+import '../app/error_message.dart';
+import '../app/load_state.dart';
 import '../providers/providers.dart';
+import '../widgets/load_error_view.dart';
 
 /// Экран создания новой группы ламп.
 /// Загружает список устройств, позволяет выбрать нужные.
@@ -15,7 +18,6 @@ class _GroupEditScreenState extends ConsumerState<GroupEditScreen> {
   final _idCtrl = TextEditingController();
   final _nameCtrl = TextEditingController();
   final Set<String> _selectedMacs = {};
-  bool _loading = true;
   bool _saving = false;
   bool _rescanning = false;
 
@@ -34,7 +36,6 @@ class _GroupEditScreenState extends ConsumerState<GroupEditScreen> {
 
   Future<void> _loadDevices() async {
     await ref.read(devicesProvider.notifier).load();
-    if (mounted) setState(() => _loading = false);
   }
 
   /// Пересканировать сеть и перезагрузить устройства
@@ -47,17 +48,21 @@ class _GroupEditScreenState extends ConsumerState<GroupEditScreen> {
       await ref.read(devicesProvider.notifier).load();
     } catch (e) {
       if (mounted) {
-        ScaffoldMessenger.of(
+        ScaffoldMessenger.of(context).showSnackBar(
-          context,
+          SnackBar(
-        ).showSnackBar(SnackBar(content: Text('Ошибка сканирования: $e')));
+            content: Text('Ошибка сканирования: ${describeLoadError(e)}'),
-      }
+          ),
+        );
       }
+    } finally {
       if (mounted) setState(() => _rescanning = false);
     }
+  }
 
   @override
   Widget build(BuildContext context) {
-    final devices = ref.watch(devicesProvider);
+    final devicesState = ref.watch(devicesProvider);
+    final devices = devicesState.data;
 
     return Scaffold(
       appBar: AppBar(
@@ -77,11 +82,7 @@ class _GroupEditScreenState extends ConsumerState<GroupEditScreen> {
           ),
         ],
       ),
-      body: _loading
+      body: Padding(
-          ? const Center(
-              child: CircularProgressIndicator(color: Colors.deepOrange),
-            )
-          : Padding(
         padding: const EdgeInsets.all(16),
         child: Column(
           crossAxisAlignment: CrossAxisAlignment.start,
@@ -120,7 +121,9 @@ class _GroupEditScreenState extends ConsumerState<GroupEditScreen> {
                   ),
                 ),
                 TextButton(
-                        onPressed: () {
+                  onPressed: devices.isEmpty
+                      ? null
+                      : () {
                           setState(() {
                             if (_selectedMacs.length == devices.length) {
                               _selectedMacs.clear();
@@ -143,48 +146,7 @@ class _GroupEditScreenState extends ConsumerState<GroupEditScreen> {
             ),
 
             // Список устройств
-                  Expanded(
+            Expanded(child: _buildDevices(devicesState, devices)),
-                    child: devices.isEmpty
-                        ? const Center(
-                            child: Text(
-                              'Устройства не найдены.\nПопробуйте пересканировать сеть.',
-                              textAlign: TextAlign.center,
-                              style: TextStyle(color: Colors.white38),
-                            ),
-                          )
-                        : ListView.builder(
-                            itemCount: devices.length,
-                            itemBuilder: (context, index) {
-                              final d = devices[index];
-                              final mac = _extractMac(d) ?? '';
-                              final name = _extractName(d);
-                              final ip = _extractIp(d);
-                              final selected = _selectedMacs.contains(mac);
-
-                              return CheckboxListTile(
-                                value: selected,
-                                activeColor: Colors.deepOrange,
-                                title: Text(name),
-                                subtitle: Text(
-                                  '$mac${ip != null ? ' - $ip' : ''}',
-                                  style: const TextStyle(
-                                    fontSize: 11,
-                                    color: Colors.white38,
-                                  ),
-                                ),
-                                onChanged: (v) {
-                                  setState(() {
-                                    if (v == true) {
-                                      _selectedMacs.add(mac);
-                                    } else {
-                                      _selectedMacs.remove(mac);
-                                    }
-                                  });
-                                },
-                              );
-                            },
-                          ),
-                  ),
 
             // Кнопка сохранения
             Padding(
@@ -219,6 +181,85 @@ class _GroupEditScreenState extends ConsumerState<GroupEditScreen> {
     );
   }
 
+  Widget _buildDevices(
+    LoadState<List<dynamic>> devicesState,
+    List<dynamic> devices,
+  ) {
+    if ((devicesState.isIdle || devicesState.isLoading) && devices.isEmpty) {
+      return const Center(
+        child: CircularProgressIndicator(color: Colors.deepOrange),
+      );
+    }
+
+    if (devicesState.hasError && devices.isEmpty) {
+      return LoadErrorView(
+        title: 'Не удалось загрузить устройства',
+        message: devicesState.errorMessage,
+        icon: Icons.lightbulb_outline,
+        onRetry: _loadDevices,
+      );
+    }
+
+    if (devices.isEmpty) {
+      return const Center(
+        child: Text(
+          'Устройства не найдены.\nПопробуйте пересканировать сеть.',
+          textAlign: TextAlign.center,
+          style: TextStyle(color: Colors.white38),
+        ),
+      );
+    }
+
+    final hasStatusHeader = devicesState.isLoading || devicesState.hasError;
+    final statusHeaderCount = hasStatusHeader ? 1 : 0;
+
+    return ListView.builder(
+      itemCount: devices.length + statusHeaderCount,
+      itemBuilder: (context, index) {
+        if (hasStatusHeader && index == 0) {
+          if (devicesState.isLoading) {
+            return const Padding(
+              padding: EdgeInsets.only(bottom: 12),
+              child: LinearProgressIndicator(color: Colors.deepOrange),
+            );
+          }
+
+          return LoadErrorBanner(
+            title: 'Не удалось обновить устройства',
+            message: devicesState.errorMessage,
+            onRetry: _loadDevices,
+          );
+        }
+
+        final deviceIndex = index - statusHeaderCount;
+        final d = devices[deviceIndex];
+        final mac = _extractMac(d) ?? '';
+        final name = _extractName(d);
+        final ip = _extractIp(d);
+        final selected = _selectedMacs.contains(mac);
+
+        return CheckboxListTile(
+          value: selected,
+          activeColor: Colors.deepOrange,
+          title: Text(name),
+          subtitle: Text(
+            '$mac${ip != null ? ' - $ip' : ''}',
+            style: const TextStyle(fontSize: 11, color: Colors.white38),
+          ),
+          onChanged: (v) {
+            setState(() {
+              if (v == true) {
+                _selectedMacs.add(mac);
+              } else {
+                _selectedMacs.remove(mac);
+              }
+            });
+          },
+        );
+      },
+    );
+  }
+
   /// Извлечь MAC-адрес из объекта устройства
   String? _extractMac(dynamic device) {
     if (device is Map) {
@@ -272,9 +313,9 @@ class _GroupEditScreenState extends ConsumerState<GroupEditScreen> {
       if (mounted) Navigator.of(context).pop();
     } catch (e) {
       if (mounted) {
-        ScaffoldMessenger.of(
+        ScaffoldMessenger.of(context).showSnackBar(
-          context,
+          SnackBar(content: Text('Ошибка создания: ${describeLoadError(e)}')),
-        ).showSnackBar(SnackBar(content: Text('Ошибка создания: $e')));
+        );
       }
     }
 

lib/widgets/group_card.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
+import '../app/error_message.dart';
 import '../providers/providers.dart';
 import 'color_picker.dart';
 
@@ -90,14 +91,12 @@ class _GroupCardState extends ConsumerState<GroupCard> {
                         color: Colors.white38,
                       ),
                       tooltip: 'Включить на 4 часа',
-                      onPressed: () =>
+                      onPressed: () => _setTimer4h(id),
-                          ref.read(groupsProvider.notifier).setTimer4h(id),
                     ),
                   Switch(
                     value: isOn,
                     activeThumbColor: Colors.deepOrange,
-                    onChanged: (v) =>
+                    onChanged: (v) => _toggleGroup(id, v),
-                        ref.read(groupsProvider.notifier).toggleGroup(id, v),
                   ),
                 ],
               ),
@@ -204,6 +203,32 @@ class _GroupCardState extends ConsumerState<GroupCard> {
       ),
     );
   }
+
+  Future<void> _toggleGroup(String id, bool value) async {
+    try {
+      await ref.read(groupsProvider.notifier).toggleGroup(id, value);
+    } catch (e) {
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(
+          content: Text('Ошибка управления группой: ${describeLoadError(e)}'),
+        ),
+      );
+    }
+  }
+
+  Future<void> _setTimer4h(String id) async {
+    try {
+      await ref.read(groupsProvider.notifier).setTimer4h(id);
+    } catch (e) {
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(
+          content: Text('Ошибка создания таймера: ${describeLoadError(e)}'),
+        ),
+      );
+    }
+  }
 }
 
 /// Слайдер с иконкой и подписью
@@ -324,16 +349,18 @@ class _SceneSelector extends ConsumerStatefulWidget {
 }
 
 class _SceneSelectorState extends ConsumerState<_SceneSelector> {
-  bool _loadStarted = false;
+  @override
+  void initState() {
+    super.initState();
+    Future.microtask(() => ref.read(scenesProvider.notifier).load());
+  }
 
   @override
   Widget build(BuildContext context) {
-    final scenes = ref.watch(scenesProvider);
+    final scenesState = ref.watch(scenesProvider);
+    final scenes = scenesState.data;
 
-    if (scenes.isEmpty && !_loadStarted) {
+    if ((scenesState.isIdle || scenesState.isLoading) && scenes.isEmpty) {
-      // Загрузить сцены при первом показе
-      _loadStarted = true;
-      Future.microtask(() => ref.read(scenesProvider.notifier).load());
       return const Padding(
         padding: EdgeInsets.all(8.0),
         child: Center(
@@ -346,6 +373,34 @@ class _SceneSelectorState extends ConsumerState<_SceneSelector> {
       );
     }
 
+    if (scenesState.hasError && scenes.isEmpty) {
+      return Padding(
+        padding: const EdgeInsets.all(8.0),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            Text(
+              'Не удалось загрузить сцены',
+              style: const TextStyle(color: Colors.white54, fontSize: 12),
+            ),
+            if (scenesState.errorMessage != null)
+              Padding(
+                padding: const EdgeInsets.only(top: 4),
+                child: Text(
+                  scenesState.errorMessage!,
+                  style: const TextStyle(color: Colors.white30, fontSize: 11),
+                ),
+              ),
+            TextButton.icon(
+              onPressed: _loadScenes,
+              icon: const Icon(Icons.refresh, size: 16),
+              label: const Text('Повторить'),
+            ),
+          ],
+        ),
+      );
+    }
+
     if (scenes.isEmpty) {
       return const Padding(
         padding: EdgeInsets.all(8.0),
@@ -356,7 +411,35 @@ class _SceneSelectorState extends ConsumerState<_SceneSelector> {
       );
     }
 
-    return Wrap(
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: [
+        if (scenesState.hasError)
+          Padding(
+            padding: const EdgeInsets.only(bottom: 8),
+            child: Row(
+              children: [
+                const Icon(
+                  Icons.warning_amber_rounded,
+                  size: 16,
+                  color: Colors.deepOrange,
+                ),
+                const SizedBox(width: 6),
+                const Expanded(
+                  child: Text(
+                    'Сцены не обновились',
+                    style: TextStyle(color: Colors.white38, fontSize: 12),
+                  ),
+                ),
+                IconButton(
+                  tooltip: 'Повторить',
+                  onPressed: _loadScenes,
+                  icon: const Icon(Icons.refresh, size: 16),
+                ),
+              ],
+            ),
+          ),
+        Wrap(
           spacing: 8,
           runSpacing: 4,
           children: scenes.map((scene) {
@@ -379,11 +462,24 @@ class _SceneSelectorState extends ConsumerState<_SceneSelector> {
             return ActionChip(
               label: Text(sceneName, style: const TextStyle(fontSize: 12)),
               backgroundColor: Colors.white10,
-          onPressed: () => ref
+              onPressed: () => _setScene(sceneId),
-              .read(groupsProvider.notifier)
-              .setScene(widget.groupId, sceneId),
             );
           }).toList(),
+        ),
+      ],
     );
   }
+
+  Future<void> _loadScenes() => ref.read(scenesProvider.notifier).load();
+
+  Future<void> _setScene(String sceneId) async {
+    try {
+      await ref.read(groupsProvider.notifier).setScene(widget.groupId, sceneId);
+    } catch (e) {
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(content: Text('Ошибка сцены: ${describeLoadError(e)}')),
+      );
+    }
+  }
 }

test/read_only_load_state_test.dart

@@ -6,28 +6,77 @@ import 'package:ignis_app/providers/providers.dart';
 import 'package:ignis_app/services/api_client.dart';
 
 class FakeIgnisApi extends IgnisApi {
+  Object? devicesData;
+  Object? scenesData;
   Object? tasksData;
   Object? statsData;
   Object? eventLogData;
   Object? apiKeysData;
+  Object? devicesError;
+  Object? scenesError;
   Object? tasksError;
   Object? statsError;
   Object? eventLogError;
   Object? apiKeysError;
+  Object? controlGroupError;
   Object? cancelTaskError;
   Object? revokeApiKeyError;
+  String? controlledGroupId;
+  Map<String, dynamic>? controlGroupParams;
   int? requestedDays;
   int? requestedLimit;
   String? cancelledJobId;
   String? revokedApiKey;
 
   FakeIgnisApi({
+    this.devicesData,
+    this.scenesData,
     this.tasksData,
     this.statsData,
     this.eventLogData,
     this.apiKeysData,
   });
 
+  @override
+  Future<Response> getDevices() async {
+    final error = devicesError;
+    if (error != null) throw error;
+    return Response(
+      requestOptions: RequestOptions(path: '/devices'),
+      data: devicesData,
+    );
+  }
+
+  @override
+  Future<Response> getScenes() async {
+    final error = scenesError;
+    if (error != null) throw error;
+    return Response(
+      requestOptions: RequestOptions(path: '/devices/scenes'),
+      data: scenesData,
+    );
+  }
+
+  @override
+  Future<Response> getGroups() async {
+    return Response(
+      requestOptions: RequestOptions(path: '/devices/groups'),
+      data: <Object>[],
+    );
+  }
+
+  @override
+  Future<Response> controlGroup(String id, Map<String, dynamic> params) async {
+    controlledGroupId = id;
+    controlGroupParams = params;
+    final error = controlGroupError;
+    if (error != null) throw error;
+    return Response(
+      requestOptions: RequestOptions(path: '/control/group/$id'),
+      data: <String, dynamic>{'ok': true},
+    );
+  }
+
   @override
   Future<Response> getTasks() async {
     final error = tasksError;
@@ -120,6 +169,57 @@ void main() {
     expect(api.requestedDays, 14);
   });
 
+  test('devices load exposes data state', () async {
+    final api = FakeIgnisApi(
+      devicesData: {
+        'devices': [
+          {'mac': 'AA:BB', 'name': 'Kitchen bulb'},
+        ],
+      },
+    );
+    final container = containerWith(api);
+
+    await container.read(devicesProvider.notifier).load();
+
+    final state = container.read(devicesProvider);
+    expect(state.status, LoadStatus.data);
+    expect(state.data, hasLength(1));
+  });
+
+  test('devices load exposes empty state', () async {
+    final api = FakeIgnisApi(devicesData: {'devices': <Object>[]});
+    final container = containerWith(api);
+
+    await container.read(devicesProvider.notifier).load();
+
+    final state = container.read(devicesProvider);
+    expect(state.status, LoadStatus.empty);
+    expect(state.data, isEmpty);
+  });
+
+  test('devices load error exposes message', () async {
+    final api = FakeIgnisApi(
+      devicesData: [
+        {'mac': 'AA:BB'},
+      ],
+    );
+    final container = containerWith(api);
+
+    await container.read(devicesProvider.notifier).load();
+    api.devicesError = DioException(
+      requestOptions: RequestOptions(path: '/devices'),
+      type: DioExceptionType.connectionError,
+      message: 'No route to host',
+    );
+
+    await container.read(devicesProvider.notifier).load();
+
+    final state = container.read(devicesProvider);
+    expect(state.status, LoadStatus.error);
+    expect(state.data, hasLength(1));
+    expect(state.errorMessage, contains('Backend недоступен'));
+  });
+
   test('tasks load exposes data state', () async {
     final api = FakeIgnisApi(
       tasksData: {
@@ -200,6 +300,48 @@ void main() {
     expect(api.requestedLimit, 50);
   });
 
+  test('scenes load accepts id-name map and exposes data state', () async {
+    final api = FakeIgnisApi(scenesData: {'party': 'Party', 'relax': 'Relax'});
+    final container = containerWith(api);
+
+    await container.read(scenesProvider.notifier).load();
+
+    final state = container.read(scenesProvider);
+    expect(state.status, LoadStatus.data);
+    expect(state.data, hasLength(2));
+    expect(state.data.first, containsPair('id', 'party'));
+  });
+
+  test('scenes load exposes empty state', () async {
+    final api = FakeIgnisApi(scenesData: {'scenes': <Object>[]});
+    final container = containerWith(api);
+
+    await container.read(scenesProvider.notifier).load();
+
+    final state = container.read(scenesProvider);
+    expect(state.status, LoadStatus.empty);
+    expect(state.data, isEmpty);
+  });
+
+  test('scenes load error exposes message', () async {
+    final api = FakeIgnisApi(scenesData: ['Party']);
+    final container = containerWith(api);
+
+    await container.read(scenesProvider.notifier).load();
+    api.scenesError = DioException(
+      requestOptions: RequestOptions(path: '/devices/scenes'),
+      type: DioExceptionType.connectionError,
+      message: 'No route to host',
+    );
+
+    await container.read(scenesProvider.notifier).load();
+
+    final state = container.read(scenesProvider);
+    expect(state.status, LoadStatus.error);
+    expect(state.data, hasLength(1));
+    expect(state.errorMessage, contains('Backend недоступен'));
+  });
+
   test('api keys load exposes data state', () async {
     final api = FakeIgnisApi(
       apiKeysData: {
@@ -315,4 +457,25 @@ void main() {
     );
     expect(api.revokedApiKey, 'secret');
   });
+
+  test('set scene error is not swallowed', () async {
+    final api = FakeIgnisApi();
+    final container = containerWith(api);
+    final error = DioException(
+      requestOptions: RequestOptions(path: '/control/group/kitchen'),
+      type: DioExceptionType.badResponse,
+      response: Response(
+        requestOptions: RequestOptions(path: '/control/group/kitchen'),
+        statusCode: 500,
+      ),
+    );
+    api.controlGroupError = error;
+
+    await expectLater(
+      container.read(groupsProvider.notifier).setScene('kitchen', 'party'),
+      throwsA(same(error)),
+    );
+    expect(api.controlledGroupId, 'kitchen');
+    expect(api.controlGroupParams, containsPair('scene', 'party'));
+  });
 }