TW-2046 added Validator

assets/l10n/intl_en.arb

@@ -3095,5 +3095,6 @@
   },
  "enable_notifications":"Enable notifications",
   "disable_notifications":"Disable notifications",
-  "logoutDialogWarning": "You will lose access to encrypted messages. We recommend that you enable chat backups before logging out"
+  "logoutDialogWarning": "You will lose access to encrypted messages. We recommend that you enable chat backups before logging out",
+  "this_field_cannot_be_blank":"This field cannot be blank"
 }

lib/domain/app_state/validator/verify_name_view_state.dart

@@ -0,0 +1,8 @@
+import 'package:fluffychat/presentation/state/failure.dart';
+import 'package:fluffychat/presentation/state/success.dart';
+
+class VerifyNameViewState extends UIState {}
+
+class VerifyNameFailure extends FeatureFailure {
+  const VerifyNameFailure(dynamic exception) : super(exception: exception);
+}

lib/domain/exception/verify_name_exception.dart

@@ -0,0 +1,17 @@
+import 'package:equatable/equatable.dart';
+
+abstract class VerifyNameException extends Equatable implements Exception {
+  static const spaceOnlyWithinName = 'The name cannot contain only spaces';
+
+  final String? message;
+
+  const VerifyNameException(this.message);
+
+  @override
+  List<Object?> get props => [message];
+}
+
+class NameWithSpaceOnlyException extends VerifyNameException {
+  const NameWithSpaceOnlyException()
+      : super(VerifyNameException.spaceOnlyWithinName);
+}

lib/domain/model/extensions/list_validator_extension.dart

@@ -0,0 +1,20 @@
+import 'package:dartz/dartz.dart';
+import 'package:fluffychat/app_state/failure.dart';
+import 'package:fluffychat/app_state/success.dart';
+import 'package:fluffychat/domain/app_state/validator/verify_name_view_state.dart';
+import 'package:fluffychat/domain/model/verification/new_name_request.dart';
+import 'package:fluffychat/domain/model/verification/validator.dart';
+
+extension ListValidatorExtension on List<Validator> {
+  Either<Failure, Success> getValidatorNameViewState(
+    NewNameRequest newNameRequest,
+  ) {
+    for (final validator in this) {
+      final either = validator.validate(newNameRequest);
+      if (either.isLeft()) {
+        return either;
+      }
+    }
+    return Right<Failure, Success>(VerifyNameViewState());
+  }
+}

lib/domain/model/extensions/validator_failure_extension.dart

@@ -0,0 +1,14 @@
+import 'package:fluffychat/domain/app_state/validator/verify_name_view_state.dart';
+import 'package:fluffychat/domain/exception/verify_name_exception.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_gen/gen_l10n/l10n.dart';
+
+extension ValidatorFailureExtension on VerifyNameFailure {
+  String getMessage(BuildContext context) {
+    if (exception is NameWithSpaceOnlyException) {
+      return L10n.of(context)!.this_field_cannot_be_blank;
+    } else {
+      return '';
+    }
+  }
+}

lib/domain/model/verification/composite_name_validator.dart

@@ -0,0 +1,20 @@
+import 'package:dartz/dartz.dart';
+import 'package:fluffychat/app_state/failure.dart';
+import 'package:fluffychat/app_state/success.dart';
+import 'package:fluffychat/domain/app_state/validator/verify_name_view_state.dart';
+import 'package:fluffychat/domain/model/verification/new_name_request.dart';
+import 'package:fluffychat/domain/model/verification/validator.dart';
+import 'package:fluffychat/domain/model/extensions/list_validator_extension.dart';
+
+class CompositeNameValidator extends Validator<NewNameRequest> {
+  final List<Validator> _listValidator;
+
+  CompositeNameValidator(this._listValidator);
+
+  @override
+  Either<Failure, Success> validate(NewNameRequest value) {
+    return _listValidator.isNotEmpty
+        ? _listValidator.getValidatorNameViewState(value)
+        : Right<Failure, Success>(VerifyNameViewState());
+  }
+}

lib/domain/model/verification/name_with_space_only_validator.dart

@@ -0,0 +1,22 @@
+import 'package:dartz/dartz.dart';
+import 'package:fluffychat/app_state/failure.dart';
+import 'package:fluffychat/app_state/success.dart';
+import 'package:fluffychat/domain/app_state/validator/verify_name_view_state.dart';
+import 'package:fluffychat/domain/exception/verify_name_exception.dart';
+import 'package:fluffychat/domain/model/verification/new_name_request.dart';
+import 'package:fluffychat/domain/model/verification/validator.dart';
+
+class NameWithSpaceOnlyValidator extends Validator<NewNameRequest> {
+  @override
+  Either<Failure, Success> validate(NewNameRequest value) {
+    if (value.value != null &&
+        value.value!.isNotEmpty &&
+        value.value!.trim().isEmpty) {
+      return const Left<Failure, Success>(
+        VerifyNameFailure(NameWithSpaceOnlyException()),
+      );
+    } else {
+      return Right<Failure, Success>(VerifyNameViewState());
+    }
+  }
+}

lib/domain/model/verification/new_name_request.dart

@@ -0,0 +1,10 @@
+import 'package:equatable/equatable.dart';
+
+class NewNameRequest with EquatableMixin {
+  final String? value;
+
+  NewNameRequest(this.value);
+
+  @override
+  List<Object?> get props => [value];
+}

lib/domain/model/verification/validator.dart

@@ -0,0 +1,7 @@
+import 'package:dartz/dartz.dart';
+import 'package:fluffychat/app_state/failure.dart';
+import 'package:fluffychat/app_state/success.dart';
+
+abstract class Validator<T> {
+  Either<Failure, Success> validate(T value);
+}

lib/domain/usecase/verify_name_interactor.dart

@@ -0,0 +1,21 @@
+import 'package:dartz/dartz.dart';
+import 'package:fluffychat/app_state/failure.dart';
+import 'package:fluffychat/app_state/success.dart';
+import 'package:fluffychat/domain/app_state/validator/verify_name_view_state.dart';
+import 'package:fluffychat/domain/model/verification/composite_name_validator.dart';
+import 'package:fluffychat/domain/model/verification/new_name_request.dart';
+import 'package:fluffychat/domain/model/verification/validator.dart';
+
+class VerifyNameInteractor {
+  Either<Failure, Success> execute(
+    String? newName,
+    List<Validator> listValidator,
+  ) {
+    try {
+      return CompositeNameValidator(listValidator)
+          .validate(NewNameRequest(newName));
+    } catch (exception) {
+      return Left<Failure, Success>(VerifyNameFailure(exception));
+    }
+  }
+}