feat: Improve enum and Variant usability

Change enums to not have unnecessary prefixes. Setup `Variant.getType` to return a `VariantType` enum instead of an integer. Add `Variant.cast<T>` to support getting an object from a Variant easily.

refs: #21

Author: fuzzybinary

src/dart/godot_dart/CHANGELOG.md

@@ -1,3 +1,9 @@
+## 0.6.0
+
+- Adjust generate global constats to avoid unnecessary prefixes.
+- Have `Variant.getType` return `VariantType` instead of int.
+- Add `Variant.cast` to support getting an object directly from a Variant.
+
 ## 0.5.2
 
 - Fix `Future<void>` throwing an error when put in a Variant, which could happen with `async` signal recievers.

src/dart/godot_dart/lib/src/core/property_info.dart

@@ -10,7 +10,7 @@ class PropertyInfo {
   PropertyInfo({
     required this.typeInfo,
     required this.name,
-    this.hint = PropertyHint.propertyHintNone,
+    this.hint = PropertyHint.none,
     this.hintString = '',
     this.flags = 6, // PropertyUsage.propertyUsageDefault
   });

src/dart/godot_dart/lib/src/variant/variant.dart

@@ -183,14 +183,20 @@ class Variant implements Finalizable {
     _attachFinalizer();
   }
 
-  int getType() {
-    return gde.ffiBindings.gde_variant_get_type(_opaque.cast());
+  VariantType getType() {
+    final cValue = gde.ffiBindings.gde_variant_get_type(_opaque.cast());
+    return VariantType.fromValue(cValue);
   }
 
   void constructCopy(GDExtensionTypePtr ptr) {
     gde.ffiBindings.gde_variant_new_copy(ptr, nativePtr.cast());
   }
 
+  T? cast<T>() {
+    var typeInfo = gde.dartBindings.getGodotTypeInfo(T);
+    return convertFromVariant(this, typeInfo) as T?;
+  }
+
   void _attachFinalizer() {
     finalizer.attach(this, _opaque.cast());
   }

src/dart/godot_dart/pubspec.yaml

@@ -1,7 +1,7 @@
 name: godot_dart
 description: Dart bindings for the Godot game engine
 repository: https://github.com/fuzzybinary/godot_dart
-version: 0.5.2
+version: 0.6.0
 
 environment:
   sdk: '>=3.2.0 <4.0.0'

tools/binding_generator/lib/src/common_helpers.dart

@@ -739,31 +739,92 @@ void writePtrReturn(ArgumentProxy argument, CodeSink o) {
   o.p('$ret;');
 }
 
+// A map of enumTypes to prefixes that are different from their type name, and
+// can be removed in Dart.
+const removePrefixes = <String, String>{
+  'KeyModifierMask': 'keyMask',
+  'Variant.Type': 'type',
+  'Error': 'err',
+  'MethodFlags': 'methodFlag',
+  'PropertyUsageFlags': 'propertyUsage',
+  'Variant.Operator': 'op',
+  'Planes': 'plane',
+};
+
+// Reserved words that get used as enum names, and should instead
+// default back to their original, prefixed names.
+final reservedWordEnumNames = [
+  'default',
+  'const',
+  'static',
+  'in',
+  'index',
+  'new',
+  'class',
+  'continue',
+];
+
+Value _transformEnumValues(Value e, String name) {
+  final lowerEnumName = name.lowerFirstLetter();
+  String originalName = e.name.toLowerCamelCase();
+  String transformedName = originalName;
+  if (originalName != lowerEnumName && originalName.startsWith(lowerEnumName)) {
+    transformedName =
+        originalName.replaceFirst(lowerEnumName, '').lowerFirstLetter();
+  } else if (removePrefixes.containsKey(name)) {
+    final prefix = removePrefixes[name]!;
+    transformedName =
+        transformedName.replaceFirst(prefix, '').lowerFirstLetter();
+  }
+
+  // Don't allow keywords
+  if (transformedName == 'int') transformedName = 'integer';
+  if (transformedName == 'enum') transformedName = 'enumVal';
+  if (reservedWordEnumNames.contains(transformedName)) {
+    transformedName = originalName;
+  }
+
+  return Value(name: transformedName, value: e.value);
+}
+
+extension EnumTransform on BuiltinClassEnum {
+  List<Value> transformedValues() {
+    return values.map((e) => _transformEnumValues(e, name)).toList();
+  }
+}
+
+extension EnumTranform on GlobalEnumElement {
+  List<Value> transformedValues() {
+    return values.map((e) => _transformEnumValues(e, name)).toList();
+  }
+}
+
 void writeEnum(dynamic godotEnum, String? inClass, CodeSink o) {
   String name;
   List<Value> valueList;
   bool isBitfield = false;
   if (godotEnum is BuiltinClassEnum) {
     name = godotEnum.name;
-    valueList = godotEnum.values;
+    valueList = godotEnum.transformedValues();
   } else if (godotEnum is GlobalEnumElement) {
     name = godotEnum.name;
-    valueList = godotEnum.values;
+    valueList = godotEnum.transformedValues();
     isBitfield = godotEnum.isBitfield;
   } else {
     throw ArgumentError(
         'Trying to write an enum that is of type ${godotEnum.runtimeType}');
   }
 
   var enumName = getEnumName(name, inClass);
+
   o.b('enum $enumName {', () {
-    if (isBitfield) {
+    if (isBitfield && valueList.where((e) => e.name == 'none').isEmpty) {
       o.p('none(0),');
     }
     for (int i = 0; i < valueList.length; ++i) {
       final value = valueList[i];
       final end = i == valueList.length - 1 ? ';' : ',';
-      o.p('${value.name.toLowerCamelCase()}(${value.value})$end');
+      o.p('${value.name}(${value.value})$end');
     }
     o.nl();
 

tools/binding_generator/lib/src/godot_api_info.dart

@@ -1,8 +1,8 @@
 import 'package:collection/collection.dart';
 import 'package:tuple/tuple.dart';
 
+import 'common_helpers.dart';
 import 'godot_extension_api_json.dart';
-import 'string_extensions.dart';
 import 'type_helpers.dart';
 
 enum TypeCategory {
@@ -98,26 +98,14 @@ class GodotApiInfo {
   }
 
   String findEnumValue(String type, String value) {
-    // Special case -- Vector3Axis was reimplemented
-    if (type == 'Vector3Axis') {
-      switch (value) {
-        case '0':
-          return 'Vector3Axis.x';
-        case '1':
-          return 'Vector3Axis.y';
-        case '2':
-          return 'Vector3Axis.z';
-      }
-    }
-
     final godotEnum = enumMap[type];
     if (godotEnum == null) return value;
 
     List<Value> valueList;
     if (godotEnum is BuiltinClassEnum) {
-      valueList = godotEnum.values;
+      valueList = godotEnum.transformedValues();
     } else if (godotEnum is GlobalEnumElement) {
-      valueList = godotEnum.values;
+      valueList = godotEnum.transformedValues();
     } else {
       throw ArgumentError(
           'Trying to write an enum that is of type ${godotEnum.runtimeType}');
@@ -126,7 +114,7 @@ class GodotApiInfo {
     final foundValue = valueList
         .firstWhereOrNull((element) => element.value.toString() == value);
     if (foundValue != null) {
-      return '$type.${foundValue.name.toLowerCamelCase()}';
+      return '$type.${foundValue.name}';
     }
 
     return value;

tools/binding_generator/lib/src/string_extensions.dart

@@ -26,4 +26,8 @@ extension StringHelpers on String {
     return lowerCamel.replaceRange(
         0, 1, lowerCamel[0].toUpperCase().toString());
   }
+
+  String lowerFirstLetter() {
+    return replaceRange(0, 1, this[0].toLowerCase().toString());
+  }
 }

tools/binding_generator/pubspec.yaml

@@ -4,7 +4,7 @@ version: 1.0.0
 publish_to: none
 
 environment:
-  sdk: '>=2.18.2 <3.0.0'
+  sdk: '>=3.5.0 <4.0.0'
 
 dependencies:
   collection: ^1.17.1