Implemented #97, removed custom skins handeling for now, made custom json converters public

Author: johnklipi

src/Json/JsonMerger.cs

@@ -0,0 +1,107 @@
+using Il2CppSystem.IO;
+using Newtonsoft.Json.Linq;
+
+namespace PolyMod.Json;
+public static class JsonMerger
+{
+    public static JObject Merge(JObject original, JObject patch)
+    {
+        foreach (var property in patch.Properties().ToArray().ToList())
+        {
+            if (property == null || property.Name == null)
+                continue;
+
+            string propName = property.Name;
+            JToken? originalValue = original[propName];
+            JToken patchValue = property.Value;
+
+            if (originalValue == null)
+            {
+                original[propName] = patchValue;
+                continue;
+            }
+
+            JObject? originalObj = originalValue.TryCast<JObject>();
+            JObject? patchObj = patchValue.TryCast<JObject>();
+            if (originalObj != null && patchObj != null)
+            {
+                Merge(originalObj, patchObj);
+                continue;
+            }
+
+            JArray? originalArr = originalValue.TryCast<JArray>();
+            JArray? patchArr = patchValue.TryCast<JArray>();
+            if (originalArr != null && patchArr != null)
+            {
+                bool isSkins = propName.Equals("skins", StringComparison.OrdinalIgnoreCase);
+                JArray merged = MergeArrays(originalArr, patchArr, isSkins);
+                original[propName] = merged;
+                continue;
+            }
+            original[propName] = patchValue;
+        }
+
+        return original;
+    }
+
+    private static JArray MergeArrays(JArray original, JArray patch, bool isSkins)
+    {
+        var result = new JArray(original);
+        var patchList = patch._values.ToArray().ToList();
+
+        bool hasDirectValues = patchList.Any(v =>
+            v.Type == JTokenType.String &&
+            !v.ToString().StartsWith("+") &&
+            !v.ToString().StartsWith("-"));
+
+        if (!isSkins && hasDirectValues)
+        {
+            result = new JArray();
+        }
+
+        foreach (var token in patchList)
+        {
+            if (token.Type != JTokenType.String)
+            {
+                result.Add(token);
+                continue;
+            }
+
+            string str = token.ToString();
+
+            if (str.StartsWith("+"))
+            {
+                string value = str.Substring(1);
+                if (!result._values.ToArray().Any(t => t.Type == JTokenType.String && t.ToString() == value))
+                {
+                    result.Add(value);
+                }
+            }
+            else if (str.StartsWith("-"))
+            {
+                string value = str.Substring(1);
+                var toRemove = result._values.ToArray()
+                    .Where(t => t.Type == JTokenType.String && t.ToString() == value)
+                    .ToList();
+                foreach (var rem in toRemove)
+                    result.Remove(rem);
+            }
+            else
+            {
+                if (isSkins)
+                {
+                    if (!result._values.ToArray().Any(t => t.Type == JTokenType.String && t.ToString() == str))
+                    {
+                        result.Add(str);
+                    }
+                }
+                else
+                {
+                    result.Add(str);
+                }
+            }
+        }
+
+        return result;
+    }
+}