Conditions #40

- Implement visitor pattern for actions.
- Refactor ConditionEvaluator and ConditionVariableVisitor to implement ActionVisitor.
- Implement variable input field for set value action of string type.
- Fix variable input field validation not showing error on invalid variable.

Author: BirjuVachhani

lib/src/api/models/action/action.dart

@@ -85,4 +85,6 @@ abstract class ActionModel with SerializableMixin {
         return ApiCallAction.fromJson(json);
     }
   }
+
+  R? accept<R>(ActionVisitor<R> visitor);
 }

lib/src/api/models/action/api_call_action.dart

@@ -2,6 +2,7 @@ import 'package:equatable/equatable.dart';
 import 'package:json_annotation/json_annotation.dart';
 
 import '../../mixins.dart';
+import '../condition.dart';
 import 'action.dart';
 
 part 'api_call_action.g.dart';
@@ -41,4 +42,7 @@ class ApiCallAction extends ActionModel with EquatableMixin, SerializableMixin {
 
   @override
   Map toJson() => _$ApiCallActionToJson(this);
+
+  @override
+  R? accept<R>(ActionVisitor<R> visitor) => visitor.visitApiCall(this);
 }

lib/src/api/models/action/call_function_action.dart

@@ -34,4 +34,8 @@ class CallFunctionAction extends ActionModel
 
   @override
   Map toJson() => _$CallFunctionActionToJson(this);
+
+  @override
+  R? accept<R>(ActionVisitor<R> visitor) =>
+      visitor.visitCallFunctionAction(this);
 }

lib/src/api/models/action/link_action.dart

@@ -6,6 +6,7 @@ import 'package:equatable/equatable.dart';
 import 'package:json_annotation/json_annotation.dart';
 
 import '../../mixins.dart';
+import '../condition.dart';
 import 'action.dart';
 
 part 'link_action.g.dart';
@@ -31,4 +32,7 @@ class LinkAction extends ActionModel with EquatableMixin, SerializableMixin {
 
   @override
   Map toJson() => _$LinkActionToJson(this);
+
+  @override
+  R? accept<R>(ActionVisitor<R> visitor) => visitor.visitLinkAction(this);
 }

lib/src/api/models/action/navigation_action.dart

@@ -6,6 +6,7 @@ import 'package:equatable/equatable.dart';
 import 'package:json_annotation/json_annotation.dart';
 
 import '../../mixins.dart';
+import '../condition.dart';
 import 'action.dart';
 
 part 'navigation_action.g.dart';
@@ -67,4 +68,7 @@ class NavigationAction extends ActionModel
 
   @override
   Map toJson() => _$NavigationActionToJson(this);
+
+  @override
+  R? accept<R>(ActionVisitor<R> visitor) => visitor.visitNavigationAction(this);
 }

lib/src/api/models/action/set_value_action.dart

@@ -45,6 +45,9 @@ class SetValueAction extends ActionModel
 
   @override
   Map toJson() => _$SetValueActionToJson(this);
+
+  @override
+  R? accept<R>(ActionVisitor<R> visitor) => visitor.visitSetValueAction(this);
 }
 
 /// Describes how to set the value.

lib/src/api/models/action/set_variable_action.dart

@@ -6,6 +6,7 @@ import 'package:equatable/equatable.dart';
 import 'package:json_annotation/json_annotation.dart';
 
 import '../../mixins.dart';
+import '../condition.dart';
 import '../variables_model.dart';
 import 'action.dart';
 
@@ -46,4 +47,7 @@ class SetVariableAction extends ActionModel
 
   @override
   Map toJson() => _$SetVariableActionToJson(this);
+
+  @override
+  R? accept<R>(ActionVisitor<R> visitor) => visitor.visitSetVariableAction(this);
 }

lib/src/api/models/action/set_variant_action.dart

@@ -44,4 +44,7 @@ class SetVariantAction extends ActionModel
 
   @override
   Map toJson() => _$SetVariantActionToJson(this);
+
+  @override
+  R? accept<R>(ActionVisitor<R> visitor) => visitor.visitSetVariantAction(this);
 }

lib/src/api/models/action/submit_action.dart

@@ -6,6 +6,7 @@ import 'package:equatable/equatable.dart';
 import 'package:json_annotation/json_annotation.dart';
 
 import '../../mixins.dart';
+import '../condition.dart';
 import 'action.dart';
 
 part 'submit_action.g.dart';
@@ -59,6 +60,9 @@ class SubmitAction extends ActionModel with EquatableMixin, SerializableMixin {
 
   @override
   Map toJson() => _$SubmitActionToJson(this);
+
+  @override
+  R? accept<R>(ActionVisitor<R> visitor) => visitor.visitSubmitAction(this);
 }
 
 /// An action that submits a form to Mailchimp.

lib/src/api/models/condition.dart

@@ -29,13 +29,13 @@ enum ConditionOperation {
   String get label {
     switch (this) {
       case ConditionOperation.equalsTo:
-        return 'Equal';
+        return 'Equals To';
       case ConditionOperation.notEqualsTo:
-        return 'Not Equals';
+        return 'Not Equal To';
       case ConditionOperation.greaterThan:
-        return 'Greater';
+        return 'Greater Than';
       case ConditionOperation.lessThan:
-        return 'Less';
+        return 'Less Than';
     }
   }
 
@@ -591,6 +591,33 @@ abstract interface class ConditionVisitor<R> {
   R? visitElseCondition(ElseCondition condition);
 }
 
+/// An interface for evaluating actions and retrieving the result.
+abstract interface class ActionVisitor<R> {
+  /// Evaluates the action and returns the result.
+  R? visitSetValueAction(SetValueAction action);
+
+  /// Evaluates the action and returns the result.
+  R? visitSetVariableAction(SetVariableAction action);
+
+  /// Evaluates the action and returns the result.
+  R? visitApiCall(ApiCallAction action);
+
+  /// Evaluates the action and returns the result.
+  R? visitNavigationAction(NavigationAction action);
+
+  /// Evaluates the action and returns the result.
+  R? visitSetVariantAction(SetVariantAction action);
+
+  /// Evaluates the action and returns the result.
+  R? visitSubmitAction(SubmitAction action);
+
+  /// Evaluates the action and returns the result.
+  R? visitLinkAction(LinkAction action);
+
+  /// Evaluates the action and returns the result.
+  R? visitCallFunctionAction(CallFunctionAction action);
+}
+
 /// An interface for evaluating expressions.
 abstract interface class ExpressionVisitor<R> {
   /// Evaluates the expression and returns the result.