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Prefab.Base/PrefabEnumJsonConverters.cs

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+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace Prefab.Base;
+
+/// <summary>
+/// Creates JSON converters that serialize Prefab enums using their logical names.
+/// </summary>
+public sealed class PrefabEnumJsonConverterFactory : JsonConverterFactory
+{
+    /// <inheritdoc />
+    public override bool CanConvert(Type typeToConvert)
+    {
+        if (!typeToConvert.IsClass)
+        {
+            return false;
+        }
+
+        var baseType = typeToConvert;
+        while (baseType is not null)
+        {
+            if (baseType.IsGenericType && baseType.GetGenericTypeDefinition() == typeof(PrefabEnum<>))
+            {
+                return true;
+            }
+
+            baseType = baseType.BaseType;
+        }
+
+        return false;
+    }
+
+    /// <inheritdoc />
+    public override JsonConverter CreateConverter(Type typeToConvert, JsonSerializerOptions options)
+    {
+        var converterType = typeof(PrefabEnumJsonConverter<>).MakeGenericType(typeToConvert);
+        return (JsonConverter)Activator.CreateInstance(converterType)!;
+    }
+
+    /// <summary>
+    /// Converter used for concrete Prefab enum types.
+    /// </summary>
+    private sealed class PrefabEnumJsonConverter<TEnum> : JsonConverter<TEnum> where TEnum : PrefabEnum<TEnum>
+    {
+        /// <inheritdoc />
+        public override TEnum? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
+        {
+            if (reader.TokenType == JsonTokenType.String)
+            {
+                var name = reader.GetString() ?? string.Empty;
+                return PrefabEnum<TEnum>.FromName(name);
+            }
+
+            if (reader.TokenType == JsonTokenType.Number && reader.TryGetInt32(out var value))
+            {
+                return PrefabEnum<TEnum>.FromValue(value);
+            }
+
+            throw new JsonException($"Unexpected token {reader.TokenType} when parsing {typeof(TEnum).Name}.");
+        }
+
+        /// <inheritdoc />
+        public override void Write(Utf8JsonWriter writer, TEnum value, JsonSerializerOptions options) => writer.WriteStringValue(value.Name);
+    }
+}