Component Instances #20

- Variants support.

Author: BirjuVachhani

lib/src/api/field_access.dart

@@ -26,7 +26,8 @@ mixin FieldsHolder {
 
   /// The complete schema of the [FieldsHolder]'s [fields].
   dynamic get fieldSchema => {
-        for (final MapEntry(:key, :value) in fields.entries) key: value.fieldSchema,
+        for (final MapEntry(:key, :value) in fields.entries)
+          key: value.fieldSchema,
       };
 }
 
@@ -304,3 +305,40 @@ final class RadiusFieldAccess extends FieldAccess<CornerRadius> {
   @override
   void setValue(Object? value) => setter(value.typedValue<CornerRadius>()!);
 }
+
+/// A field accessor for variants.
+final class VariantAccess extends FieldAccess<String> {
+  /// Constructs a new [VariantAccess] instance with the given parameters.
+  const VariantAccess(
+    super.label,
+    super.description,
+    super.getValue,
+    super.setter, {
+    required super.defaultValue,
+    // Variant ID -> Variant Name.
+    required FieldOptionsGetter<String> options,
+  }) : getOptions = options;
+
+  /// The options of the field. Variant ID -> Variant Name.
+  final FieldOptionsGetter<String> getOptions;
+
+  @override
+  String get dynamicKeyType => 'options';
+
+  @override
+  dynamic serialize(String? obj) => obj;
+
+  @override
+  Map<String, dynamic> get supplementarySchema => {
+        'options': {
+          for (final String name in getOptions()) name: name,
+        },
+      };
+
+  @override
+  void setValue(Object? value) {
+    if (value case String? value) {
+      setter(value ?? getDefaultValue!());
+    }
+  }
+}

lib/src/api/nodes/variance_node.dart

@@ -1,6 +1,8 @@
 import 'package:codelessly_json_annotation/codelessly_json_annotation.dart';
+import 'package:collection/collection.dart';
 import 'package:equatable/equatable.dart';
 
+import '../field_access.dart';
 import '../mixins.dart';
 import '../models/models.dart';
 import 'nodes.dart';
@@ -59,6 +61,22 @@ class VarianceNode extends SinglePlaceholderNode with CustomPropertiesMixin {
   @override
   covariant VarianceProperties properties;
 
+  @override
+  late final Map<String, FieldAccess> fields = {
+    'currentVariantId': VariantAccess(
+      () => 'Variant',
+      () => 'Select a variant to load',
+      () => currentVariant.name,
+      (String name) {
+        final String? newId =
+            variants.firstWhereOrNull((e) => e.name == name)?.id;
+        if (newId != null) currentVariantId = newId;
+      },
+      options: () => variants.map((variant) => variant.name).toList(),
+      defaultValue: () => 'default',
+    ),
+  };
+
   /// Creates a [VarianceNode] instance with the given data.
   VarianceNode({
     bool? value,