1 files changed, 79 insertions, 0 deletions
diff --git a/src/Ryujinx.Common/Configuration/Hid/Controller/Motion/JsonMotionConfigControllerConverter.cs b/src/Ryujinx.Common/Configuration/Hid/Controller/Motion/JsonMotionConfigControllerConverter.cs
new file mode 100644
index 00000000..2b9e0af4
--- /dev/null
+++ b/src/Ryujinx.Common/Configuration/Hid/Controller/Motion/JsonMotionConfigControllerConverter.cs
@@ -0,0 +1,79 @@
+using Ryujinx.Common.Utilities;
+using System;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace Ryujinx.Common.Configuration.Hid.Controller.Motion
+{
+    class JsonMotionConfigControllerConverter : JsonConverter<MotionConfigController>
+    {
+        private static readonly MotionConfigJsonSerializerContext SerializerContext = new(JsonHelper.GetDefaultSerializerOptions());
+
+        private static MotionInputBackendType GetMotionInputBackendType(ref Utf8JsonReader reader)
+        {
+            // Temporary reader to get the backend type
+            Utf8JsonReader tempReader = reader;
+
+            MotionInputBackendType result = MotionInputBackendType.Invalid;
+
+            while (tempReader.Read())
+            {
+                // NOTE: We scan all properties ignoring the depth entirely on purpose.
+                // The reason behind this is that we cannot track in a reliable way the depth of the object because Utf8JsonReader never emit the first TokenType == StartObject if the json start with an object.
+                // As such, this code will try to parse very field named "motion_backend" to the correct enum.
+                if (tempReader.TokenType == JsonTokenType.PropertyName)
+                {
+                    string propertyName = tempReader.GetString();
+
+                    if (propertyName.Equals("motion_backend"))
+                    {
+                        tempReader.Read();
+
+                        if (tempReader.TokenType == JsonTokenType.String)
+                        {
+                            string backendTypeRaw = tempReader.GetString();
+
+                            if (!Enum.TryParse(backendTypeRaw, out result))
+                            {
+                                result = MotionInputBackendType.Invalid;
+                            }
+                            else
+                            {
+                                break;
+                            }
+                        }
+                    }
+                }
+            }
+
+            return result;
+        }
+
+        public override MotionConfigController Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
+        {
+            MotionInputBackendType motionBackendType = GetMotionInputBackendType(ref reader);
+
+            return motionBackendType switch
+            {
+                MotionInputBackendType.GamepadDriver => JsonSerializer.Deserialize(ref reader, SerializerContext.StandardMotionConfigController),
+                MotionInputBackendType.CemuHook => JsonSerializer.Deserialize(ref reader, SerializerContext.CemuHookMotionConfigController),
+                _ => throw new InvalidOperationException($"Unknown backend type {motionBackendType}"),
+            };
+        }
+
+        public override void Write(Utf8JsonWriter writer, MotionConfigController value, JsonSerializerOptions options)
+        {
+            switch (value.MotionBackend)
+            {
+                case MotionInputBackendType.GamepadDriver:
+                    JsonSerializer.Serialize(writer, value as StandardMotionConfigController, SerializerContext.StandardMotionConfigController);
+                    break;
+                case MotionInputBackendType.CemuHook:
+                    JsonSerializer.Serialize(writer, value as CemuHookMotionConfigController, SerializerContext.CemuHookMotionConfigController);
+                    break;
+                default:
+                    throw new ArgumentException($"Unknown motion backend type {value.MotionBackend}");
+            }
+        }
+    }
+}