TF-4195 Add interactor/repository/datasource to feature add a Label to an email

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

@@ -11,6 +11,7 @@ import 'package:jmap_dart_client/jmap/core/properties/properties.dart';
 import 'package:jmap_dart_client/jmap/core/session/session.dart';
 import 'package:jmap_dart_client/jmap/core/state.dart' as jmap;
 import 'package:jmap_dart_client/jmap/mail/email/email.dart';
+import 'package:jmap_dart_client/jmap/mail/email/keyword_identifier.dart';
 import 'package:model/email/email_content.dart';
 import 'package:model/email/mark_star_action.dart';
 import 'package:model/email/read_actions.dart';
@@ -160,4 +161,10 @@ abstract class EmailRepository {
   Future<void> printEmail(EmailPrint emailPrint);
 
   Future<String> generateEntireMessageAsDocument(ViewEntireMessageRequest entireMessageRequest);
+
+  Future<void> addLabelToEmail(
+    AccountId accountId,
+    EmailId emailId,
+    KeyWordIdentifier labelKeyword,
+  );
 }

lib/features/email/domain/state/add_a_label_to_an_email_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 AddingALabelToAnEmail extends LoadingState {}
+
+class AddALabelToAnEmailSuccess extends UIState {
+  final EmailId emailId;
+  final KeyWordIdentifier labelKeyword;
+  final String labelDisplay;
+
+  AddALabelToAnEmailSuccess(this.emailId, this.labelKeyword, this.labelDisplay);
+
+  @override
+  List<Object> get props => [emailId, labelKeyword, labelDisplay];
+}
+
+class AddALabelToAnEmailFailure extends FeatureFailure {
+  final String labelDisplay;
+
+  AddALabelToAnEmailFailure({
+    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_an_email_interactor.dart

@@ -0,0 +1,40 @@
+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/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_email_state.dart';
+
+class AddALabelToAnEmailInteractor {
+  final EmailRepository _emailRepository;
+
+  AddALabelToAnEmailInteractor(this._emailRepository);
+
+  Stream<Either<Failure, Success>> execute(
+    AccountId accountId,
+    EmailId emailId,
+    KeyWordIdentifier labelKeyword,
+    String labelDisplay,
+  ) async* {
+    try {
+      yield Right(AddingALabelToAnEmail());
+      await _emailRepository.addLabelToEmail(
+        accountId,
+        emailId,
+        labelKeyword,
+      );
+      yield Right(AddALabelToAnEmailSuccess(
+        emailId,
+        labelKeyword,
+        labelDisplay,
+      ));
+    } catch (e) {
+      yield Left(AddALabelToAnEmailFailure(
+        exception: e,
+        labelDisplay: labelDisplay,
+      ));
+    }
+  }
+}