TF-4195 Add Label to Thread

lib/features/base/widget/popup_menu/popup_submenu_controller.dart

@@ -68,9 +68,9 @@ class PopupSubmenuController {
               shape: const RoundedRectangleBorder(
                 borderRadius: BorderRadius.all(Radius.circular(6)),
               ),
-              child: SizedBox(
+              child: Container(
                 width: submenuWidth,
-                height: finalHeight,
+                constraints: BoxConstraints(maxHeight: finalHeight),
                 child: submenu,
               ),
             ),

lib/features/email/data/datasource/email_datasource.dart

@@ -211,4 +211,11 @@ abstract class EmailDataSource {
     EmailId emailId,
     KeyWordIdentifier labelKeyword,
   );
+
+  Future<void> addLabelToThread(
+    Session session,
+    AccountId accountId,
+    List<EmailId> emailIds,
+    KeyWordIdentifier labelKeyword,
+  );
 }

lib/features/email/data/datasource_impl/email_datasource_impl.dart

@@ -570,4 +570,21 @@ class EmailDataSourceImpl extends EmailDataSource {
       );
     }).catchError(_exceptionThrower.throwException);
   }
+
+  @override
+  Future<void> addLabelToThread(
+    Session session,
+    AccountId accountId,
+    List<EmailId> emailIds,
+    KeyWordIdentifier labelKeyword,
+  ) {
+    return Future.sync(() async {
+      return await emailAPI.addLabelToThread(
+        session,
+        accountId,
+        emailIds,
+        labelKeyword,
+      );
+    }).catchError(_exceptionThrower.throwException);
+  }
 }

lib/features/email/data/datasource_impl/email_hive_cache_datasource_impl.dart

@@ -580,4 +580,9 @@ class EmailHiveCacheDataSourceImpl extends EmailDataSource {
   Future<void> addLabelToEmail(Session session, AccountId accountId, EmailId emailId, KeyWordIdentifier labelKeyword) {
     throw UnimplementedError();
   }
+
+  @override
+  Future<void> addLabelToThread(Session session, AccountId accountId, List<EmailId> emailIds, KeyWordIdentifier labelKeyword) {
+    throw UnimplementedError();
+  }
 }

lib/features/email/data/datasource_impl/email_local_storage_datasource_impl.dart

@@ -356,4 +356,9 @@ class EmailLocalStorageDataSourceImpl extends EmailDataSource {
   Future<void> addLabelToEmail(Session session, AccountId accountId, EmailId emailId, KeyWordIdentifier labelKeyword) {
     throw UnimplementedError();
   }
+
+  @override
+  Future<void> addLabelToThread(Session session, AccountId accountId, List<EmailId> emailIds, KeyWordIdentifier labelKeyword) {
+    throw UnimplementedError();
+  }
 }

lib/features/email/data/datasource_impl/email_session_storage_datasource_impl.dart

@@ -270,4 +270,9 @@ class EmailSessionStorageDatasourceImpl extends EmailDataSource {
   Future<void> addLabelToEmail(Session session, AccountId accountId, EmailId emailId, KeyWordIdentifier labelKeyword) {
     throw UnimplementedError();
   }
+
+  @override
+  Future<void> addLabelToThread(Session session, AccountId accountId, List<EmailId> emailIds, KeyWordIdentifier labelKeyword) {
+    throw UnimplementedError();
+  }
 }

lib/features/email/data/network/email_api.dart

@@ -964,4 +964,36 @@ class EmailAPI with HandleSetErrorMixin, MailAPIMixin {
       throw parseErrorForSetResponse(response, emailId.id);
     }
   }
+
+  Future<void> addLabelToThread(
+    Session session,
+    AccountId accountId,
+    List<EmailId> emailIds,
+    KeyWordIdentifier labelKeyword,
+  ) async {
+    final method = SetEmailMethod(accountId)
+      ..addUpdates(emailIds.generateMapUpdateObjectLabel(labelKeyword));
+
+    final builder = JmapRequestBuilder(_httpClient, ProcessingInvocation());
+    final invocation = builder.invocation(method);
+
+    final capabilities = method.requiredCapabilities
+        .toCapabilitiesSupportTeamMailboxes(session, accountId);
+    final result = await (builder..usings(capabilities)).build().execute();
+
+    final response = result.parse<SetEmailResponse>(
+      invocation.methodCallId,
+      SetEmailResponse.deserialize,
+    );
+
+    final emailIdsUpdated = response?.updated?.keys ?? <Id>[];
+    final ids = emailIds.map((emailId) => emailId.id);
+    final isUpdated = emailIdsUpdated.every(ids.contains);
+
+    if (emailIdsUpdated.isEmpty || !isUpdated) {
+      for (var id in emailIds) {
+        throw parseErrorForSetResponse(response, id.id);
+      }
+    }
+  }
 }

lib/features/email/data/repository/email_repository_impl.dart

@@ -495,4 +495,19 @@ class EmailRepositoryImpl extends EmailRepository {
       labelKeyword,
     );
   }
+
+  @override
+  Future<void> addLabelToThread(
+    Session session,
+    AccountId accountId,
+    List<EmailId> emailIds,
+    KeyWordIdentifier labelKeyword,
+  ) {
+    return emailDataSource[DataSourceType.network]!.addLabelToThread(
+      session,
+      accountId,
+      emailIds,
+      labelKeyword,
+    );
+  }
 }

lib/features/email/domain/repository/email_repository.dart

@@ -168,4 +168,11 @@ abstract class EmailRepository {
     EmailId emailId,
     KeyWordIdentifier labelKeyword,
   );
+
+  Future<void> addLabelToThread(
+    Session session,
+    AccountId accountId,
+    List<EmailId> emailIds,
+    KeyWordIdentifier labelKeyword,
+  );
 }

lib/features/email/domain/state/add_a_label_to_an_thread_state.dart

@@ -0,0 +1,29 @@
+import 'package:core/presentation/state/failure.dart';
+import 'package:core/presentation/state/success.dart';
+import 'package:jmap_dart_client/jmap/mail/email/email.dart';
+import 'package:jmap_dart_client/jmap/mail/email/keyword_identifier.dart';
+
+class AddingALabelToAThread extends LoadingState {}
+
+class AddALabelToAThreadSuccess extends UIState {
+  final List<EmailId> emailIds;
+  final KeyWordIdentifier labelKeyword;
+  final String labelDisplay;
+
+  AddALabelToAThreadSuccess(this.emailIds, this.labelKeyword, this.labelDisplay);
+
+  @override
+  List<Object> get props => [emailIds, labelKeyword, labelDisplay];
+}
+
+class AddALabelToAThreadFailure extends FeatureFailure {
+  final String labelDisplay;
+
+  AddALabelToAThreadFailure({
+    dynamic exception,
+    required this.labelDisplay,
+  }) : super(exception: exception);
+
+  @override
+  List<Object?> get props => [...super.props, labelDisplay];
+}

lib/features/email/domain/usecases/add_a_label_to_a_thread_interactor.dart

@@ -0,0 +1,43 @@
+import 'package:core/presentation/state/failure.dart';
+import 'package:core/presentation/state/success.dart';
+import 'package:dartz/dartz.dart';
+import 'package:jmap_dart_client/jmap/account_id.dart';
+import 'package:jmap_dart_client/jmap/core/session/session.dart';
+import 'package:jmap_dart_client/jmap/mail/email/email.dart';
+import 'package:jmap_dart_client/jmap/mail/email/keyword_identifier.dart';
+import 'package:tmail_ui_user/features/email/domain/repository/email_repository.dart';
+import 'package:tmail_ui_user/features/email/domain/state/add_a_label_to_an_thread_state.dart';
+
+class AddALabelToAThreadInteractor {
+  final EmailRepository _emailRepository;
+
+  AddALabelToAThreadInteractor(this._emailRepository);
+
+  Stream<Either<Failure, Success>> execute(
+    Session session,
+    AccountId accountId,
+    List<EmailId> emailIds,
+    KeyWordIdentifier labelKeyword,
+    String labelDisplay,
+  ) async* {
+    try {
+      yield Right(AddingALabelToAThread());
+      await _emailRepository.addLabelToThread(
+        session,
+        accountId,
+        emailIds,
+        labelKeyword,
+      );
+      yield Right(AddALabelToAThreadSuccess(
+        emailIds,
+        labelKeyword,
+        labelDisplay,
+      ));
+    } catch (e) {
+      yield Left(AddALabelToAThreadFailure(
+        exception: e,
+        labelDisplay: labelDisplay,
+      ));
+    }
+  }
+}

lib/features/email/presentation/extensions/handle_label_for_email_extension.dart

@@ -1,6 +1,5 @@
 import 'package:core/utils/platform_info.dart';
 import 'package:dartz/dartz.dart';
-import 'package:get/get.dart';
 import 'package:jmap_dart_client/jmap/account_id.dart';
 import 'package:jmap_dart_client/jmap/core/session/session.dart';
 import 'package:jmap_dart_client/jmap/mail/email/email.dart';
@@ -15,6 +14,7 @@ import 'package:tmail_ui_user/features/email/presentation/extensions/presentatio
 import 'package:tmail_ui_user/features/home/data/exceptions/session_exceptions.dart';
 import 'package:tmail_ui_user/features/labels/domain/exceptions/label_exceptions.dart';
 import 'package:tmail_ui_user/features/labels/presentation/widgets/add_label_to_email_modal.dart';
+import 'package:tmail_ui_user/features/mailbox_dashboard/presentation/extensions/labels/check_label_available_extension.dart';
 import 'package:tmail_ui_user/features/mailbox_dashboard/presentation/extensions/update_current_emails_flags_extension.dart';
 import 'package:tmail_ui_user/features/thread/data/extensions/map_keywords_extension.dart';
 import 'package:tmail_ui_user/features/thread/domain/extensions/presentation_email_map_extension.dart';
@@ -23,8 +23,7 @@ import 'package:tmail_ui_user/main/routes/dialog_router.dart';
 
 extension HandleLabelForEmailExtension on SingleEmailController {
   bool get isLabelFeatureEnabled {
-    return mailboxDashBoardController.isLabelCapabilitySupported &&
+    return mailboxDashBoardController.isLabelFeatureEnabled;
-        mailboxDashBoardController.labelController.isLabelSettingEnabled.isTrue;
   }
 
   void toggleLabelToEmail(EmailId emailId, Label label, bool isSelected) {
@@ -180,8 +179,12 @@ extension HandleLabelForEmailExtension on SingleEmailController {
       child: AddLabelToEmailModal(
         labels: labels,
         emailLabels: emailLabels,
-        emailId: emailId,
+        emailIds: [emailId],
-        onAddLabelToEmailCallback: toggleLabelToEmail,
+        onAddLabelToEmailsCallback: (emailIds, label, isSelected) {
+          if (emailIds.length == 1) {
+            toggleLabelToEmail(emailIds.first, label, isSelected);
+          }
+        },
       ),
       dialogLabel: 'add-label-to-email-modal',
     );

lib/features/email/presentation/utils/email_action_reactor/email_action_reactor.dart

@@ -45,6 +45,7 @@ import 'package:tmail_ui_user/features/email/domain/usecases/get_email_content_i
 import 'package:tmail_ui_user/features/email/domain/usecases/mark_as_email_read_interactor.dart';
 import 'package:tmail_ui_user/features/email/domain/usecases/mark_as_star_email_interactor.dart';
 import 'package:tmail_ui_user/features/email/domain/usecases/print_email_interactor.dart';
+import 'package:tmail_ui_user/features/email/presentation/extensions/presentation_email_extension.dart';
 import 'package:tmail_ui_user/features/email/presentation/model/context_item_email_action.dart';
 import 'package:tmail_ui_user/features/email/presentation/model/email_loaded.dart';
 import 'package:tmail_ui_user/features/email/presentation/model/email_unsubscribe.dart';
@@ -588,7 +589,6 @@ class EmailActionReactor {
         );
       }).toList();
 
-
       final popupMenuWidget = PopupMenuActionGroupWidget(
         actions: popupMenuItemEmailActions,
         submenuController: submenuController,
@@ -623,9 +623,12 @@ class EmailActionReactor {
     OnSelectLabelAction? onSelectLabelAction,
   }) {
     if (actionType == EmailActionType.labelAs && labels?.isNotEmpty == true) {
+      final listLabels = labels ?? [];
+      final emailLabels = presentationEmail.getLabelList(listLabels);
+
       return LabelListContextMenu(
-        labelList: labels ?? [],
+        labelList: listLabels,
-        presentationEmail: presentationEmail,
+        emailLabels: emailLabels,
         imagePaths: imagePaths,
         onSelectLabelAction: (label, isSelected) =>
             onSelectLabelAction?.call(label, isSelected),

lib/features/labels/presentation/widgets/add_label_to_email_modal.dart

@@ -12,8 +12,8 @@ import 'package:tmail_ui_user/features/labels/presentation/widgets/label_item_co
 import 'package:tmail_ui_user/main/localizations/app_localizations.dart';
 import 'package:tmail_ui_user/main/routes/route_navigation.dart';
 
-typedef OnAddLabelToEmailCallback = void Function(
+typedef OnAddLabelToEmailsCallback = void Function(
-  EmailId emailId,
+  List<EmailId> emailIds,
   Label label,
   bool isSelected,
 );
@@ -21,15 +21,15 @@ typedef OnAddLabelToEmailCallback = void Function(
 class AddLabelToEmailModal extends StatefulWidget {
   final List<Label> labels;
   final List<Label> emailLabels;
-  final EmailId emailId;
+  final List<EmailId> emailIds;
-  final OnAddLabelToEmailCallback onAddLabelToEmailCallback;
+  final OnAddLabelToEmailsCallback onAddLabelToEmailsCallback;
 
   const AddLabelToEmailModal({
     super.key,
     required this.labels,
     required this.emailLabels,
-    required this.emailId,
+    required this.emailIds,
-    required this.onAddLabelToEmailCallback,
+    required this.onAddLabelToEmailsCallback,
   });
 
   @override
@@ -146,7 +146,7 @@ class _AddLabelToEmailModalState extends State<AddLabelToEmailModal> {
   }
 
   void _onSelectLabel(Label label, bool isSelected) {
-    widget.onAddLabelToEmailCallback(widget.emailId, label, isSelected);
+    widget.onAddLabelToEmailsCallback(widget.emailIds, label, isSelected);
     popBack();
   }
 

lib/features/labels/presentation/widgets/label_list_context_menu.dart

@@ -1,28 +1,24 @@
 import 'package:core/presentation/resources/image_paths.dart';
 import 'package:flutter/material.dart';
 import 'package:labels/model/label.dart';
-import 'package:model/email/presentation_email.dart';
-import 'package:tmail_ui_user/features/email/presentation/extensions/presentation_email_extension.dart';
 import 'package:tmail_ui_user/features/labels/presentation/widgets/label_item_context_menu.dart';
 
 class LabelListContextMenu extends StatelessWidget {
-  final PresentationEmail presentationEmail;
   final List<Label> labelList;
+  final List<Label> emailLabels;
   final ImagePaths imagePaths;
   final OnSelectLabelAction onSelectLabelAction;
 
   const LabelListContextMenu({
     super.key,
     required this.labelList,
-    required this.presentationEmail,
+    required this.emailLabels,
     required this.imagePaths,
     required this.onSelectLabelAction,
   });
 
   @override
   Widget build(BuildContext context) {
-    final emailLabels = presentationEmail.getLabelList(labelList);
-
     return ListView.builder(
       shrinkWrap: true,
       itemCount: labelList.length,

lib/features/mailbox_dashboard/presentation/bindings/mailbox_dashboard_bindings.dart

@@ -33,6 +33,7 @@ import 'package:tmail_ui_user/features/email/data/local/html_analyzer.dart';
 import 'package:tmail_ui_user/features/email/data/network/email_api.dart';
 import 'package:tmail_ui_user/features/email/data/repository/email_repository_impl.dart';
 import 'package:tmail_ui_user/features/email/domain/repository/email_repository.dart';
+import 'package:tmail_ui_user/features/email/domain/usecases/add_a_label_to_a_thread_interactor.dart';
 import 'package:tmail_ui_user/features/email/domain/usecases/delete_email_permanently_interactor.dart';
 import 'package:tmail_ui_user/features/email/domain/usecases/delete_multiple_emails_permanently_interactor.dart';
 import 'package:tmail_ui_user/features/download/domain/usecase/download_all_attachments_for_web_interactor.dart';
@@ -370,6 +371,7 @@ class MailboxDashBoardBindings extends BaseBindings {
         Get.find<EmailRepository>(),
     ));
     Get.lazyPut(() => MarkAsStarMultipleEmailInteractor(Get.find<EmailRepository>()));
+    Get.lazyPut(() => AddALabelToAThreadInteractor(Get.find<EmailRepository>()));
     Get.lazyPut(() => MoveMultipleEmailToMailboxInteractor(
         Get.find<EmailRepository>(),
     ));

lib/features/mailbox_dashboard/presentation/extensions/labels/check_label_available_extension.dart

@@ -0,0 +1,9 @@
+import 'package:get/get.dart';
+import 'package:tmail_ui_user/features/mailbox_dashboard/presentation/controller/mailbox_dashboard_controller.dart';
+
+extension CheckLabelAvailableExtension on MailboxDashBoardController {
+  bool get isLabelFeatureEnabled {
+    return isLabelCapabilitySupported &&
+        labelController.isLabelSettingEnabled.isTrue;
+  }
+}

lib/features/thread/data/extensions/map_keywords_extension.dart

@@ -9,6 +9,13 @@ extension MapKeywordsExtension on Map<KeyWordIdentifier, bool>? {
   List<KeyWordIdentifier> get enabledKeywords =>
       this?.entries.where((e) => e.value).map((e) => e.key).toList() ?? [];
 
+  Set<KeyWordIdentifier> get enabledKeywordSet => this == null
+      ? const {}
+      : {
+          for (final entry in this!.entries)
+            if (entry.value) entry.key
+        };
+
   Map<KeyWordIdentifier, bool> withKeyword(KeyWordIdentifier keyword) {
     return Map<KeyWordIdentifier, bool>.from(this ?? {})..[keyword] = true;
   }

lib/features/thread/domain/extensions/presentation_email_map_extension.dart

@@ -16,4 +16,21 @@ extension PresentationEmailMapExtension on Map<EmailId, PresentationEmail?> {
     }
     return newMap;
   }
+
+  Map<EmailId, PresentationEmail?> toggleListEmailsKeywordByIds({
+    required List<EmailId> emailIds,
+    required KeyWordIdentifier keyword,
+    required bool remove,
+  }) {
+    final updatedMap = Map<EmailId, PresentationEmail?>.from(this);
+
+    for (final emailId in emailIds) {
+      final email = updatedMap[emailId];
+      if (email == null) continue;
+
+      updatedMap[emailId] = email.toggleKeyword(keyword, remove);
+    }
+
+    return updatedMap;
+  }
 }

lib/features/thread_detail/domain/extensions/list_email_in_thread_detail_info_extension.dart

@@ -1,9 +1,12 @@
 import 'package:jmap_dart_client/jmap/mail/email/email.dart';
 import 'package:jmap_dart_client/jmap/mail/email/keyword_identifier.dart';
+import 'package:labels/model/label.dart';
+import 'package:tmail_ui_user/features/thread/data/extensions/map_keywords_extension.dart';
 import 'package:tmail_ui_user/features/thread_detail/domain/extensions/email_in_thread_detail_info_extension.dart';
 import 'package:tmail_ui_user/features/thread_detail/domain/model/email_in_thread_detail_info.dart';
 
-extension ListEmailInThreadDetailInfoExtension on List<EmailInThreadDetailInfo> {
+extension ListEmailInThreadDetailInfoExtension
+    on List<EmailInThreadDetailInfo> {
   List<EmailId> emailIdsToDisplay(bool isSentMailbox) => isSentMailbox
       ? map((email) => email.emailId).toList()
       : where((email) => email.isValidToDisplay)
@@ -22,4 +25,48 @@ extension ListEmailInThreadDetailInfoExtension on List<EmailInThreadDetailInfo>
       return emailInfo.toggleKeyword(keyword, remove);
     }).toList();
   }
+
+  List<EmailInThreadDetailInfo> toggleListEmailsKeywordByIds({
+    required List<EmailId> emailIds,
+    required KeyWordIdentifier keyword,
+    required bool remove,
+  }) {
+    final targetIds = emailIds.toSet();
+
+    return map((emailInfo) {
+      if (!targetIds.contains(emailInfo.emailId)) {
+        return emailInfo;
+      }
+
+      return emailInfo.toggleKeyword(keyword, remove);
+    }).toList();
+  }
+
+  List<Label> findCommonLabelsInThread({
+    required List<Label> labels,
+  }) {
+    if (isEmpty || labels.isEmpty) return const [];
+
+    final iterator = where((e) => e.isValidToDisplay).iterator;
+    if (!iterator.moveNext()) return const [];
+
+    // Initialize with the first valid email
+    var commonKeywords = iterator.current.keywords.enabledKeywordSet;
+
+    if (commonKeywords.isEmpty) return const [];
+
+    // Intersect with remaining emails
+    while (iterator.moveNext()) {
+      commonKeywords = commonKeywords.intersection(
+        iterator.current.keywords.enabledKeywordSet,
+      );
+
+      if (commonKeywords.isEmpty) return const [];
+    }
+
+    return labels
+        .where((label) =>
+            label.keyword != null && commonKeywords.contains(label.keyword))
+        .toList();
+  }
 }

lib/features/thread_detail/presentation/extension/labels/add_label_to_thread_extension.dart

@@ -0,0 +1,181 @@
+import 'package:dartz/dartz.dart';
+import 'package:jmap_dart_client/jmap/account_id.dart';
+import 'package:jmap_dart_client/jmap/core/session/session.dart';
+import 'package:jmap_dart_client/jmap/mail/email/email.dart';
+import 'package:jmap_dart_client/jmap/mail/email/keyword_identifier.dart';
+import 'package:labels/labels.dart';
+import 'package:tmail_ui_user/features/email/domain/state/add_a_label_to_an_thread_state.dart';
+import 'package:tmail_ui_user/features/email/presentation/extensions/email_loaded_extension.dart';
+import 'package:tmail_ui_user/features/home/data/exceptions/session_exceptions.dart';
+import 'package:tmail_ui_user/features/labels/domain/exceptions/label_exceptions.dart';
+import 'package:tmail_ui_user/features/labels/presentation/widgets/add_label_to_email_modal.dart';
+import 'package:tmail_ui_user/features/mailbox_dashboard/presentation/extensions/labels/check_label_available_extension.dart';
+import 'package:tmail_ui_user/features/mailbox_dashboard/presentation/extensions/update_current_emails_flags_extension.dart';
+import 'package:tmail_ui_user/features/thread/domain/extensions/presentation_email_map_extension.dart';
+import 'package:tmail_ui_user/features/thread_detail/domain/extensions/list_email_in_thread_detail_info_extension.dart';
+import 'package:tmail_ui_user/features/thread_detail/presentation/thread_detail_controller.dart';
+import 'package:tmail_ui_user/main/routes/dialog_router.dart';
+
+extension AddLabelToThreadExtension on ThreadDetailController {
+  Future<void> openAddLabelToEmailDialogModal() async {
+    if (!mailboxDashBoardController.isLabelFeatureEnabled) return;
+
+    final labels = mailboxDashBoardController.labelController.labels;
+    if (emailsInThreadDetailInfo.isEmpty || labels.isEmpty) {
+      return;
+    }
+
+    final threadLabels =
+        emailsInThreadDetailInfo.findCommonLabelsInThread(labels: labels);
+
+    final emailIds = emailsInThreadDetailInfo.emailIdsToDisplay(true);
+
+    await DialogRouter().openDialogModal(
+      child: AddLabelToEmailModal(
+        labels: labels,
+        emailLabels: threadLabels,
+        emailIds: emailIds,
+        onAddLabelToEmailsCallback: (emailIds, label, isSelected) {
+          toggleLabelToThread(label, isSelected, currentEmailIds: emailIds);
+        },
+      ),
+      dialogLabel: 'add-label-to-thread-modal',
+    );
+  }
+
+  void toggleLabelToThread(
+    Label label,
+    bool isSelected, {
+    List<EmailId>? currentEmailIds,
+  }) {
+    if (isSelected) {
+      final accountId = mailboxDashBoardController.accountId.value;
+      final session = mailboxDashBoardController.sessionCurrent;
+      final emailIds =
+          currentEmailIds ?? emailsInThreadDetailInfo.emailIdsToDisplay(true);
+
+      _addALabelToAThread(
+        session: session,
+        accountId: accountId,
+        emailIds: emailIds,
+        label: label,
+      );
+    }
+  }
+
+  void _addALabelToAThread({
+    required Session? session,
+    required AccountId? accountId,
+    required Label label,
+    required List<EmailId> emailIds,
+  }) {
+    final labelDisplay = label.safeDisplayName;
+
+    if (session == null) {
+      consumeState(
+        Stream.value(
+          Left(AddALabelToAThreadFailure(
+            exception: NotFoundSessionException(),
+            labelDisplay: labelDisplay,
+          )),
+        ),
+      );
+      return;
+    }
+
+    if (accountId == null) {
+      consumeState(
+        Stream.value(
+          Left(AddALabelToAThreadFailure(
+            exception: NotFoundAccountIdException(),
+            labelDisplay: labelDisplay,
+          )),
+        ),
+      );
+      return;
+    }
+
+    final labelKeyword = label.keyword;
+    if (labelKeyword == null) {
+      consumeState(
+        Stream.value(Left(
+          AddALabelToAThreadFailure(
+            exception: LabelKeywordIsNull(),
+            labelDisplay: labelDisplay,
+          ),
+        )),
+      );
+      return;
+    }
+
+    consumeState(addALabelToAThreadInteractor.execute(
+      session,
+      accountId,
+      emailIds,
+      labelKeyword,
+      label.safeDisplayName,
+    ));
+  }
+
+  void handleAddLabelToThreadSuccess(AddALabelToAThreadSuccess success) {
+    toastManager.showMessageSuccess(success);
+
+    _autoSyncLabelToThreadOnMemory(
+      emailIds: success.emailIds,
+      labelKeyword: success.labelKeyword,
+    );
+  }
+
+  void handleAddLabelToThreadFailure(AddALabelToAThreadFailure failure) {
+    toastManager.showMessageFailure(failure);
+  }
+
+  void _autoSyncLabelToThreadOnMemory({
+    required List<EmailId> emailIds,
+    required KeyWordIdentifier labelKeyword,
+  }) {
+    _updateLabelInThreadOnMemory(
+      emailIds: emailIds,
+      labelKeyword: labelKeyword,
+    );
+  }
+
+  void _updateLabelInThreadOnMemory({
+    required List<EmailId> emailIds,
+    required KeyWordIdentifier labelKeyword,
+  }) {
+    emailIdsPresentation.value =
+        emailIdsPresentation.toggleListEmailsKeywordByIds(
+      emailIds: emailIds,
+      keyword: labelKeyword,
+      remove: false,
+    );
+
+    emailsInThreadDetailInfo.value =
+        emailsInThreadDetailInfo.toggleListEmailsKeywordByIds(
+      emailIds: emailIds,
+      keyword: labelKeyword,
+      remove: false,
+    );
+
+    final emailLoaded = currentEmailLoaded.value;
+    final emailLoadedId = emailLoaded?.emailCurrent?.id;
+    if (emailLoaded != null &&
+        emailLoadedId != null &&
+        emailIds.contains(emailLoadedId)) {
+      currentEmailLoaded.value = emailLoaded.toggleEmailKeyword(
+        emailId: emailLoadedId,
+        keyword: labelKeyword,
+        remove: false,
+      );
+    }
+
+    mailboxDashBoardController.updateEmailFlagByEmailIds(
+      emailIds,
+      isLabelAdded: true,
+      labelKeyword: labelKeyword,
+    );
+
+    mailboxDashBoardController.labelController.isLabelSettingEnabled.refresh();
+  }
+}

lib/features/thread_detail/presentation/extension/on_thread_detail_action_click.dart

@@ -1,23 +1,32 @@
+import 'package:core/presentation/resources/image_paths.dart';
 import 'package:core/utils/platform_info.dart';
 import 'package:dartz/dartz.dart';
 import 'package:flutter/material.dart';
 import 'package:jmap_dart_client/jmap/mail/mailbox/mailbox.dart';
+import 'package:labels/model/label.dart';
 import 'package:model/email/email_action_type.dart';
 import 'package:model/email/mark_star_action.dart';
 import 'package:model/email/read_actions.dart';
 import 'package:model/mailbox/presentation_mailbox.dart';
 import 'package:tmail_ui_user/features/base/widget/popup_menu/popup_menu_action_group_widget.dart';
+import 'package:tmail_ui_user/features/base/widget/popup_menu/popup_submenu_controller.dart';
 import 'package:tmail_ui_user/features/destination_picker/presentation/model/destination_picker_arguments.dart';
 import 'package:tmail_ui_user/features/email/presentation/action/email_ui_action.dart';
 import 'package:tmail_ui_user/features/email/presentation/model/context_item_email_action.dart';
 import 'package:tmail_ui_user/features/email/presentation/model/popup_menu_item_email_action.dart';
 import 'package:tmail_ui_user/features/home/data/exceptions/session_exceptions.dart';
+import 'package:tmail_ui_user/features/labels/presentation/widgets/label_item_context_menu.dart';
+import 'package:tmail_ui_user/features/labels/presentation/widgets/label_list_context_menu.dart';
 import 'package:tmail_ui_user/features/mailbox/presentation/model/mailbox_actions.dart';
 import 'package:tmail_ui_user/features/mailbox_dashboard/presentation/extensions/handle_open_context_menu_extension.dart';
+import 'package:tmail_ui_user/features/mailbox_dashboard/presentation/extensions/labels/check_label_available_extension.dart';
 import 'package:tmail_ui_user/features/thread/domain/state/mark_as_multiple_email_read_state.dart';
 import 'package:tmail_ui_user/features/thread/domain/state/mark_as_star_multiple_email_state.dart';
+import 'package:tmail_ui_user/features/thread_detail/domain/extensions/list_email_in_thread_detail_info_extension.dart';
+import 'package:tmail_ui_user/features/thread_detail/domain/model/email_in_thread_detail_info.dart';
 import 'package:tmail_ui_user/features/thread_detail/presentation/extension/close_thread_detail_action.dart';
 import 'package:tmail_ui_user/features/thread_detail/presentation/extension/get_thread_detail_action_status.dart';
+import 'package:tmail_ui_user/features/thread_detail/presentation/extension/labels/add_label_to_thread_extension.dart';
 import 'package:tmail_ui_user/features/thread_detail/presentation/extension/parsing_email_opened_properties_extension.dart';
 import 'package:tmail_ui_user/features/thread_detail/presentation/thread_detail_controller.dart';
 import 'package:tmail_ui_user/main/localizations/app_localizations.dart';
@@ -115,6 +124,10 @@ extension OnThreadDetailActionClick on ThreadDetailController {
 
         _moveToMailbox(mailboxId, threadDetailActionType);
         break;
+      case EmailActionType.labelAs:
+        if (!mailboxDashBoardController.isLabelFeatureEnabled) return;
+        openAddLabelToEmailDialogModal();
+        break;
       default:
         break;
     }
@@ -124,6 +137,8 @@ extension OnThreadDetailActionClick on ThreadDetailController {
     if (currentContext == null) return;
 
     final moreActions = [
+      if (mailboxDashBoardController.isLabelFeatureEnabled)
+        EmailActionType.labelAs,
       threadDetailIsRead
           ? EmailActionType.markAsUnread
           : EmailActionType.markAsRead,
@@ -158,6 +173,8 @@ extension OnThreadDetailActionClick on ThreadDetailController {
         useGroupedActions: true,
       );
     } else {
+      final submenuController = PopupSubmenuController();
+
       final popupMenuItemEmailActions = moreActions.map((actionType) {
         return PopupMenuItemEmailAction(
           actionType,
@@ -165,13 +182,27 @@ extension OnThreadDetailActionClick on ThreadDetailController {
           imagePaths,
           key: '${actionType.name}_action',
           category: actionType.category,
+          submenu: _getEmailActionSubmenu(
+            actionType: actionType,
+            imagePaths: imagePaths,
+            emailInThreadDetailInfos: emailsInThreadDetailInfo,
+            labels: mailboxDashBoardController.labelController.labels,
+            onSelectLabelAction: (label, isSelected) {
+              toggleLabelToThread(label, isSelected);
+              submenuController.hide();
+              popBack();
+            },
+          ),
         );
       }).toList();
 
       final popupMenuWidget = PopupMenuActionGroupWidget(
         actions: popupMenuItemEmailActions,
+        submenuController: submenuController,
         onActionSelected: (action) {
-          onThreadDetailActionClick(action.action);
+          if (_shouldHandleAction(action.action)) {
+            onThreadDetailActionClick(action.action);
+          }
         },
       );
 
@@ -179,8 +210,39 @@ extension OnThreadDetailActionClick on ThreadDetailController {
         currentContext!,
         position,
         popupMenuWidget,
+      ).whenComplete(submenuController.hide);
+    }
+  }
+
+  bool _shouldHandleAction(EmailActionType action) {
+    if (action != EmailActionType.labelAs) {
+      return true;
+    }
+
+    return PlatformInfo.isWebTouchDevice || PlatformInfo.isMobile;
+  }
+
+  Widget? _getEmailActionSubmenu({
+    required EmailActionType actionType,
+    required ImagePaths imagePaths,
+    required List<EmailInThreadDetailInfo> emailInThreadDetailInfos,
+    required List<Label>? labels,
+    OnSelectLabelAction? onSelectLabelAction,
+  }) {
+    if (actionType == EmailActionType.labelAs && labels?.isNotEmpty == true) {
+      final listLabels = labels ?? [];
+      final threadLabels =
+          emailInThreadDetailInfos.findCommonLabelsInThread(labels: listLabels);
+
+      return LabelListContextMenu(
+        labelList: listLabels,
+        emailLabels: threadLabels,
+        imagePaths: imagePaths,
+        onSelectLabelAction: (label, isSelected) =>
+            onSelectLabelAction?.call(label, isSelected),
       );
     }
+    return null;
   }
 
   void _moveToMailbox(MailboxId mailboxId, EmailActionType emailActionType) {

lib/features/thread_detail/presentation/thread_detail_bindings.dart

@@ -2,6 +2,7 @@ import 'package:core/data/model/source_type/data_source_type.dart';
 import 'package:get/get.dart';
 import 'package:jmap_dart_client/http/http_client.dart';
 import 'package:tmail_ui_user/features/base/base_bindings.dart';
+import 'package:tmail_ui_user/features/email/domain/usecases/add_a_label_to_a_thread_interactor.dart';
 import 'package:tmail_ui_user/features/email/domain/usecases/get_email_content_interactor.dart';
 import 'package:tmail_ui_user/features/email/domain/usecases/mark_as_email_read_interactor.dart';
 import 'package:tmail_ui_user/features/email/domain/usecases/mark_as_star_email_interactor.dart';
@@ -45,6 +46,7 @@ class ThreadDetailBindings extends BaseBindings {
       Get.find<GetEmailContentInteractor>(),
       Get.find<MarkAsStarMultipleEmailInteractor>(),
       Get.find<MarkAsMultipleEmailReadInteractor>(),
+      Get.find<AddALabelToAThreadInteractor>(),
     ));
   }
 

lib/features/thread_detail/presentation/thread_detail_controller.dart

@@ -16,8 +16,10 @@ import 'package:model/email/presentation_email.dart';
 import 'package:model/extensions/keyword_identifier_extension.dart';
 import 'package:model/mailbox/presentation_mailbox.dart';
 import 'package:tmail_ui_user/features/base/base_controller.dart';
+import 'package:tmail_ui_user/features/email/domain/state/add_a_label_to_an_thread_state.dart';
 import 'package:tmail_ui_user/features/email/domain/state/mark_as_email_read_state.dart';
 import 'package:tmail_ui_user/features/email/domain/state/print_email_state.dart';
+import 'package:tmail_ui_user/features/email/domain/usecases/add_a_label_to_a_thread_interactor.dart';
 import 'package:tmail_ui_user/features/email/domain/usecases/get_email_content_interactor.dart';
 import 'package:tmail_ui_user/features/email/domain/usecases/mark_as_email_read_interactor.dart';
 import 'package:tmail_ui_user/features/email/domain/usecases/mark_as_star_email_interactor.dart';
@@ -49,6 +51,7 @@ import 'package:tmail_ui_user/features/thread_detail/presentation/extension/hand
 import 'package:tmail_ui_user/features/thread_detail/presentation/extension/handle_mail_shortcut_actions_extension.dart';
 import 'package:tmail_ui_user/features/thread_detail/presentation/extension/handle_refresh_thread_detail_action.dart';
 import 'package:tmail_ui_user/features/thread_detail/presentation/extension/initialize_thread_detail_emails.dart';
+import 'package:tmail_ui_user/features/thread_detail/presentation/extension/labels/add_label_to_thread_extension.dart';
 import 'package:tmail_ui_user/features/thread_detail/presentation/extension/mark_collapsed_email_unread_success.dart';
 import 'package:tmail_ui_user/features/thread_detail/presentation/extension/quick_create_rule_from_collapsed_email_success.dart';
 import 'package:tmail_ui_user/features/thread_detail/presentation/extension/thread_detail_on_selected_email_updated.dart';
@@ -66,6 +69,7 @@ class ThreadDetailController extends BaseController {
   final GetEmailContentInteractor _getEmailContentInteractor;
   final MarkAsStarMultipleEmailInteractor markAsStarMultipleEmailInteractor;
   final MarkAsMultipleEmailReadInteractor markAsMultipleEmailReadInteractor;
+  final AddALabelToAThreadInteractor addALabelToAThreadInteractor;
 
   ThreadDetailController(
     this._getEmailIdsByThreadIdInteractor,
@@ -76,6 +80,7 @@ class ThreadDetailController extends BaseController {
     this._getEmailContentInteractor,
     this.markAsStarMultipleEmailInteractor,
     this.markAsMultipleEmailReadInteractor,
+    this.addALabelToAThreadInteractor,
   );
 
   final emailIdsPresentation = <EmailId, PresentationEmail?>{}.obs;
@@ -260,6 +265,8 @@ class ThreadDetailController extends BaseController {
       );
     } else if (success is CreateNewRuleFilterSuccess) {
       quickCreateRuleFromCollapsedEmailSuccess(success);
+    } else if (success is AddALabelToAThreadSuccess) {
+      handleAddLabelToThreadSuccess(success);
     } else {
       super.handleSuccessViewState(success);
     }
@@ -269,26 +276,24 @@ class ThreadDetailController extends BaseController {
   void handleFailureViewState(failure) {
     if (failure is GetThreadByIdFailure) {
       handleGetThreadByIdFailure(failure);
-    }
+    } else if (failure is GetEmailsByIdsFailure) {
-    if (failure is GetEmailsByIdsFailure) {
       if (failure.updateCurrentThreadDetail) return;
       showRetryToast(failure);
-      return;
+    } else if (failure is PrintEmailFailure) {
-    }
-    if (failure is PrintEmailFailure) {
       if (currentOverlayContext != null && currentContext != null) {
         appToast.showToastErrorMessage(
           currentOverlayContext!,
           AppLocalizations.of(currentContext!).unknownError,
         );
       }
-      return;
+    } else if (failure is MarkAsMultipleEmailReadFailure ||
-    }
-    if (failure is MarkAsMultipleEmailReadFailure ||
         failure is MarkAsStarMultipleEmailFailure) {
       toastManager.showMessageFailure(failure as FeatureFailure);
+    } else if (failure is AddALabelToAThreadFailure) {
+      handleAddLabelToThreadFailure(failure);
+    } else {
+      super.handleFailureViewState(failure);
     }
-    super.handleFailureViewState(failure);
   }
 
   @override

lib/l10n/intl_messages.arb

@@ -4880,6 +4880,24 @@
     "placeholders_order": [],
     "placeholders": {}
   },
+  "aiScribe": "AI Scribe",
+  "@aiScribe": {
+    "type": "text",
+    "placeholders_order": [],
+    "placeholders": {}
+  },
+  "aiScribeSettingExplanation": "Use AI to help write and improve your emails",
+  "@aiScribeSettingExplanation": {
+    "type": "text",
+    "placeholders_order": [],
+    "placeholders": {}
+  },
+  "aiScribeToggleDescription": "Enable AI Scribe",
+  "@aiScribeToggleDescription": {
+    "type": "text",
+    "placeholders_order": [],
+    "placeholders": {}
+  },
   "showMoreAttachmentButton": "Show +{count} more",
   "@showMoreAttachmentButton": {
     "type": "text",
@@ -5321,5 +5339,25 @@
     "type": "text",
     "placeholders_order": [],
     "placeholders": {}
+  },
+  "addLabelToThreadSuccessfullyMessage": "All emails in thread added to the \"{labelName}\" label",
+  "@addLabelToThreadSuccessfullyMessage": {
+    "type": "text",
+    "placeholders_order": [
+      "labelName"
+    ],
+    "placeholders": {
+      "labelName": {}
+    }
+  },
+  "addLabelToThreadFailureMessage": "Cannot add all emails in thread to the \"{labelName}\" label",
+  "@addLabelToThreadFailureMessage": {
+    "type": "text",
+    "placeholders_order": [
+      "labelName"
+    ],
+    "placeholders": {
+      "labelName": {}
+    }
   }
 }

lib/main/localizations/app_localizations.dart

@@ -5649,4 +5649,21 @@ class AppLocalizations {
       name: 'addLabel',
     );
   }
+
+  String addLabelToThreadSuccessfullyMessage(String labelName) {
+    return Intl.message(
+      'All emails in thread added to the "$labelName" label',
+      name: 'addLabelToThreadSuccessfullyMessage',
+      args: [labelName],
+    );
+  }
+
+  String addLabelToThreadFailureMessage(String labelName) {
+    return Intl.message(
+      'Cannot add all emails in thread to the "$labelName" label',
+      name: 'addLabelToThreadFailureMessage',
+      args: [labelName],
+    );
+  }
+
 }

lib/main/utils/toast_manager.dart

@@ -23,6 +23,7 @@ import 'package:tmail_ui_user/features/composer/domain/exceptions/set_method_exc
 import 'package:tmail_ui_user/features/email/domain/exceptions/calendar_event_exceptions.dart';
 import 'package:tmail_ui_user/features/email/domain/model/move_action.dart';
 import 'package:tmail_ui_user/features/email/domain/state/add_a_label_to_an_email_state.dart';
+import 'package:tmail_ui_user/features/email/domain/state/add_a_label_to_an_thread_state.dart';
 import 'package:tmail_ui_user/features/email/domain/state/calendar_event_reply_state.dart';
 import 'package:tmail_ui_user/features/email/domain/state/mark_as_email_star_state.dart';
 import 'package:tmail_ui_user/features/download/domain/state/parse_email_by_blob_id_state.dart';
@@ -205,6 +206,9 @@ class ToastManager {
     } else if (failure is AddALabelToAnEmailFailure) {
       message = message ??
           appLocalizations.addLabelToEmailFailureMessage(failure.labelDisplay);
+    } else if (failure is AddALabelToAThreadFailure) {
+      message = message ??
+          appLocalizations.addLabelToThreadFailureMessage(failure.labelDisplay);
     }
     log('ToastManager::showMessageFailure: Message: $message');
     if (message?.trim().isNotEmpty == true) {
@@ -276,6 +280,10 @@ class ToastManager {
       message = appLocalizations.addLabelToEmailSuccessfullyMessage(
         success.labelDisplay,
       );
+    } else if (success is AddALabelToAThreadSuccess) {
+      message = appLocalizations.addLabelToThreadSuccessfullyMessage(
+        success.labelDisplay,
+      );
     }
     log('ToastManager::showMessageSuccess: Message: $message');
     if (message?.trim().isNotEmpty == true) {

model/lib/extensions/list_email_id_extension.dart

@@ -50,4 +50,13 @@ extension ListEmailIdExtension on List<EmailId> {
         emailId.id: KeyWordIdentifier.emailForwarded.generateForwardedActionPath()
     };
   }
+
+  Map<Id, PatchObject> generateMapUpdateObjectLabel(
+    KeyWordIdentifier labelKeyword,
+  ) {
+    return {
+      for (var emailId in this)
+        emailId.id: labelKeyword.generateLabelActionPath()
+    };
+  }
 }

scribe/lib/scribe.dart

@@ -23,7 +23,7 @@ export 'scribe/ai/presentation/model/text_selection_model.dart';
 export 'scribe/ai/presentation/styles/ai_scribe_styles.dart';
 export 'scribe/ai/presentation/utils/ai_scribe_constants.dart';
 export 'scribe/ai/presentation/utils/context_menu/hover_submenu_controller.dart';
-export 'scribe/ai/presentation/utils/context_menu/popup_submenu_controller.dart';
+export 'scribe/ai/presentation/utils/context_menu/context_submenu_controller.dart';
 export 'scribe/ai/presentation/utils/modal/ai_scribe_modal_manager.dart';
 export 'scribe/ai/presentation/utils/modal/anchored_modal_layout_calculator.dart';
 export 'scribe/ai/presentation/widgets/button/ai_assistant_button.dart';

scribe/lib/scribe/ai/presentation/utils/context_menu/context_submenu_controller.dart

@@ -4,7 +4,7 @@ import 'package:flutter/material.dart';
 
 enum SubmenuDirection { left, right, auto }
 
-class PopupSubmenuController {
+class ContextSubmenuController {
   OverlayEntry? _submenuEntry;
 
   bool get isShowing => _submenuEntry != null;

scribe/lib/scribe/ai/presentation/utils/modal/ai_scribe_modal_manager.dart

@@ -16,7 +16,7 @@ class AiScribeModalManager {
     ModalPlacement? preferredPlacement,
     ModalCrossAxisAlignment crossAxisAlignment = ModalCrossAxisAlignment.center,
   }) async {
-    final PopupSubmenuController submenuController = PopupSubmenuController();
+    final ContextSubmenuController submenuController = ContextSubmenuController();
 
     final aiAction = await Get.dialog<AIAction>(
       AiScribeModalWidget(

scribe/lib/scribe/ai/presentation/widgets/context_menu/ai_scribe_context_menu.dart

@@ -6,7 +6,7 @@ class AiScribeContextMenu extends StatefulWidget {
   final ImagePaths imagePaths;
   final List<AiScribeContextMenuAction> menuActions;
   final ValueChanged<AiScribeContextMenuAction> onActionSelected;
-  final PopupSubmenuController? submenuController;
+  final ContextSubmenuController? submenuController;
 
   const AiScribeContextMenu({
     super.key,

scribe/lib/scribe/ai/presentation/widgets/modal/ai_scribe_modal_widget.dart

@@ -13,7 +13,7 @@ class AiScribeModalWidget extends StatelessWidget {
   final Size? buttonSize;
   final ModalPlacement? preferredPlacement;
   final ModalCrossAxisAlignment crossAxisAlignment;
-  final PopupSubmenuController? submenuController;
+  final ContextSubmenuController? submenuController;
 
   const AiScribeModalWidget({
     super.key,

test/features/thread_detail/presentation/extension/list_email_in_thread_detail_info_extension_test.dart

@@ -0,0 +1,218 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:jmap_dart_client/jmap/core/id.dart';
+import 'package:jmap_dart_client/jmap/mail/email/email.dart';
+import 'package:jmap_dart_client/jmap/mail/email/keyword_identifier.dart';
+import 'package:jmap_dart_client/jmap/mail/mailbox/mailbox.dart';
+import 'package:labels/model/label.dart';
+import 'package:tmail_ui_user/features/thread_detail/domain/extensions/list_email_in_thread_detail_info_extension.dart';
+import 'package:tmail_ui_user/features/thread_detail/domain/model/email_in_thread_detail_info.dart';
+
+void main() {
+  group(
+    'ListEmailInThreadDetailInfoExtension.findCommonLabelsInThread',
+    () {
+      final seen = KeyWordIdentifier.emailSeen;
+      final flagged = KeyWordIdentifier.emailFlagged;
+      final answered = KeyWordIdentifier.emailAnswered;
+
+      Label label(KeyWordIdentifier keyword) => Label(
+            keyword: keyword,
+            displayName: keyword.value,
+          );
+
+      EmailInThreadDetailInfo email({
+        required Map<KeyWordIdentifier, bool>? keywords,
+        bool isValidToDisplay = true,
+      }) {
+        return EmailInThreadDetailInfo(
+          emailId: EmailId(Id('email-${keywords.hashCode}')),
+          keywords: keywords,
+          mailboxIds: {MailboxId(Id('inbox')): true},
+          isValidToDisplay: isValidToDisplay,
+        );
+      }
+
+      test(
+        'returns empty list when email list is empty',
+        () {
+          final result = <EmailInThreadDetailInfo>[].findCommonLabelsInThread(
+            labels: [label(seen)],
+          );
+
+          expect(result, isEmpty);
+        },
+      );
+
+      test(
+        'returns empty list when labels list is empty',
+        () {
+          final emails = [
+            email(keywords: {seen: true}),
+          ];
+
+          final result = emails.findCommonLabelsInThread(labels: []);
+
+          expect(result, isEmpty);
+        },
+      );
+
+      test(
+        'returns only labels whose keyword appears in all valid emails',
+        () {
+          final emails = [
+            email(
+              keywords: {
+                seen: true,
+                flagged: true,
+              },
+            ),
+            email(
+              keywords: {
+                seen: true,
+                flagged: false,
+              },
+            ),
+            email(
+              keywords: {
+                seen: true,
+              },
+            ),
+          ];
+
+          final labels = [
+            label(seen),
+            label(flagged),
+            label(answered),
+          ];
+
+          final result = emails.findCommonLabelsInThread(labels: labels);
+
+          expect(
+            result.map((l) => l.keyword),
+            equals([seen]),
+          );
+        },
+      );
+
+      test(
+        'ignores emails that are not valid to display',
+        () {
+          final emails = [
+            email(
+              keywords: {
+                seen: true,
+                flagged: true,
+              },
+            ),
+            email(
+              keywords: {
+                flagged: true,
+              },
+              isValidToDisplay: false,
+            ),
+            email(
+              keywords: {
+                seen: true,
+              },
+            ),
+          ];
+
+          final labels = [
+            label(seen),
+            label(flagged),
+          ];
+
+          final result = emails.findCommonLabelsInThread(labels: labels);
+
+          expect(
+            result.map((l) => l.keyword),
+            equals([seen]),
+          );
+        },
+      );
+
+      test(
+        'returns empty list when no common keyword exists',
+        () {
+          final emails = [
+            email(
+              keywords: {
+                seen: true,
+              },
+            ),
+            email(
+              keywords: {
+                flagged: true,
+              },
+            ),
+          ];
+
+          final labels = [
+            label(seen),
+            label(flagged),
+          ];
+
+          final result = emails.findCommonLabelsInThread(labels: labels);
+
+          expect(result, isEmpty);
+        },
+      );
+
+      test(
+        'returns empty list when first valid email has no enabled keywords',
+        () {
+          final emails = [
+            email(
+              keywords: {
+                seen: false,
+                flagged: false,
+              },
+            ),
+            email(
+              keywords: {
+                seen: true,
+              },
+            ),
+          ];
+
+          final labels = [
+            label(seen),
+            label(flagged),
+          ];
+
+          final result = emails.findCommonLabelsInThread(labels: labels);
+
+          expect(result, isEmpty);
+        },
+      );
+
+      test(
+        'ignores labels with null keyword',
+        () {
+          final emails = [
+            email(
+              keywords: {
+                seen: true,
+              },
+            ),
+            email(
+              keywords: {
+                seen: true,
+              },
+            ),
+          ];
+
+          final labels = [
+            Label(displayName: 'No keyword'),
+            label(seen),
+          ];
+
+          final result = emails.findCommonLabelsInThread(labels: labels);
+
+          expect(result.length, 1);
+          expect(result.first.keyword, seen);
+        },
+      );
+    },
+  );
+}