fix: various problems

docs/presets.md

@@ -446,6 +446,8 @@ This preset is a generator for the meta model `ConstrainedEnumModel` and [can be
 | Method | Description | Additional arguments |
 |---|---|---|
 | `item` | A method to extend enum's item. | `item` object as a [`ConstrainedEnumValueModel`](./internal-model.md#the-constrained-meta-model) instance, which contains the value and key of enum's item. |
+| `extension` | A method to extend the enums extension class. |  |
+| `extensionMethods` | A method to extend the enums extension class methods instead of the whole class. |  |
 
 ### Rust
 #### **Struct**

examples/csharp-generate-json-serializer/__snapshots__/index.spec.ts.snap

@@ -22,21 +22,14 @@ public partial class Root
     {
       return JsonSerializer.Serialize(this, options);
     }
-    public static Root Deserialize(string json)
+    public static Root Deserialize(string json, JsonSerializerOptions options = null)
     {
-      var deserializeOptions = new JsonSerializerOptions();
-      deserializeOptions.Converters.Add(new RootConverter());
-      return JsonSerializer.Deserialize<Root>(json, deserializeOptions);
+      return JsonSerializer.Deserialize<Root>(json, options);
     }
 }
 
 internal class RootConverter : JsonConverter<Root>
 {
-  public override bool CanConvert(System.Type objectType)
-  {
-    // this converter can be applied to any type
-    return true;
-  }
   public override Root Read(ref Utf8JsonReader reader, System.Type typeToConvert, JsonSerializerOptions options)
   {
     if (reader.TokenType != JsonTokenType.StartObject)
@@ -60,10 +53,12 @@ internal class RootConverter : JsonConverter<Root>
       }
 
       string propertyName = reader.GetString();
+
+      // Advance to the value token
+      reader.Read();
       if (propertyName == \\"email\\")
         {
-          var value = JsonSerializer.Deserialize<string?>(ref reader, options);
-          instance.Email = value;
+          instance.Email = JsonSerializer.Deserialize<string?>(ref reader);
           continue;
         }
     }
@@ -72,26 +67,19 @@ internal class RootConverter : JsonConverter<Root>
   }
   public override void Write(Utf8JsonWriter writer, Root value, JsonSerializerOptions options)
   {
-    if (value == null)
-    {
-      JsonSerializer.Serialize(writer, null, options);
-      return;
-    }
-    var properties = value.GetType().GetProperties();
+    var properties = value?.GetType().GetProperties();
 
     writer.WriteStartObject();
 
-    if(value.Email != null) {
+    if(value?.Email != null) {
       // write property name and let the serializer serialize the value itself
       writer.WritePropertyName(\\"email\\");
-      JsonSerializer.Serialize(writer, value.Email, options);
+      JsonSerializer.Serialize(writer, value?.Email, options);
     }
 
 
     writer.WriteEndObject();
   }
-
-}
-",
+}",
 ]
 `;

examples/csharp-overwrite-enum-naming/__snapshots__/index.spec.ts.snap

@@ -9,33 +9,32 @@ Array [
   Delivered,
   Cancelled
 }
-
-public static class OrderStatusExtensions
-{
-  public static int? GetValue(this OrderStatus enumValue)
+  public static class OrderStatusExtensions
   {
-    switch (enumValue)
+    public static int? GetValue(this OrderStatus enumValue)
     {
-      case OrderStatus.Ordered: return 30;
-      case OrderStatus.UnderDelivery: return 40;
-      case OrderStatus.Delivered: return 50;
-      case OrderStatus.Cancelled: return 99;
+      switch (enumValue)
+      {
+        case OrderStatus.Ordered: return 30;
+        case OrderStatus.UnderDelivery: return 40;
+        case OrderStatus.Delivered: return 50;
+        case OrderStatus.Cancelled: return 99;
+      }
+      return null;
     }
-    return null;
-  }
 
-  public static OrderStatus? ToOrderStatus(dynamic? value)
-  {
-    switch (value)
+    public static OrderStatus? ToOrderStatus(dynamic? value)
     {
-      case 30: return OrderStatus.Ordered;
-      case 40: return OrderStatus.UnderDelivery;
-      case 50: return OrderStatus.Delivered;
-      case 99: return OrderStatus.Cancelled;
+      switch (value)
+      {
+        case 30: return OrderStatus.Ordered;
+        case 40: return OrderStatus.UnderDelivery;
+        case 50: return OrderStatus.Delivered;
+        case 99: return OrderStatus.Cancelled;
+      }
+      return null;
     }
-    return null;
   }
-}
 ",
 ]
 `;

src/generators/csharp/CSharpPreset.ts

@@ -5,7 +5,8 @@ import {
   PresetArgs,
   PropertyArgs,
   ConstrainedObjectModel,
-  InterfacePreset
+  InterfacePreset,
+  ConstrainedEnumModel
 } from '../../models';
 import { CSharpOptions } from './CSharpGenerator';
 import {
@@ -40,12 +41,18 @@ export interface CsharpRecordPreset<O>
 
 export type ClassPresetType<O> = CsharpClassPreset<O>;
 export type RecordPresetType<O> = CsharpRecordPreset<O>;
-export type EnumPresetType<O> = EnumPreset<EnumRenderer, O>;
-
+export interface EnumPresetType<O> extends EnumPreset<EnumRenderer, O> {
+  extension?: (
+    args: PresetArgs<EnumRenderer, O, ConstrainedEnumModel>
+  ) => Promise<string> | string;
+  extensionMethods?: (
+    args: PresetArgs<EnumRenderer, O, ConstrainedEnumModel>
+  ) => Promise<string> | string;
+}
 export type CSharpPreset<O = any> = Preset<{
   class: CsharpClassPreset<O>;
   record: CsharpRecordPreset<O>;
-  enum: EnumPreset<EnumRenderer, O>;
+  enum: EnumPresetType<O>;
 }>;
 
 export const CSHARP_DEFAULT_PRESET: CSharpPreset<CSharpOptions> = {

src/generators/csharp/constrainer/EnumConstrainer.ts

@@ -75,6 +75,12 @@ export function defaultEnumKeyConstraints(
 export function defaultEnumValueConstraints(): CSharpEnumValueConstraint {
   return ({ enumValue }) => {
     let normalizedEnumValue;
+    if (enumValue === null) {
+      return enumValue;
+    }
+    if (Array.isArray(enumValue)) {
+      return `"${JSON.stringify(enumValue).replace(/"/g, '\\"')}"`;
+    }
     switch (typeof enumValue) {
       case 'boolean':
       case 'bigint':