From 34988065887fdc5ac1fdf48ae083acbb8a1ddd62 Mon Sep 17 00:00:00 2001
From: Wojtek Figat <wojtek@figat.pl>
Date: Sat, 19 Aug 2023 17:45:42 +0200
Subject: [PATCH] Add support for accessing scripting properties via
 `ManagedBinaryModule` fields API

---
 Source/Engine/Scripting/BinaryModule.cpp | 110 +++++++++++++++++++----
 1 file changed, 93 insertions(+), 17 deletions(-)

diff --git a/Source/Engine/Scripting/BinaryModule.cpp b/Source/Engine/Scripting/BinaryModule.cpp
index 6ffdb14a9..820c919f3 100644
--- a/Source/Engine/Scripting/BinaryModule.cpp
+++ b/Source/Engine/Scripting/BinaryModule.cpp
@@ -9,6 +9,7 @@
 #include "ManagedCLR/MClass.h"
 #include "ManagedCLR/MMethod.h"
 #include "ManagedCLR/MField.h"
+#include "ManagedCLR/MProperty.h"
 #include "ManagedCLR/MUtils.h"
 #include "ManagedCLR/MException.h"
 #include "FlaxEngine.Gen.h"
@@ -1324,47 +1325,97 @@ void ManagedBinaryModule::GetMethodSignature(void* method, ScriptingTypeMethodSi
 #endif
 }
 
+// Pointers with the highest bit turned on are properties
+#if PLATFORM_64BITS
+#define ManagedBinaryModuleFieldIsPropertyBit (uintptr)(1ull << 63)
+#else
+#define ManagedBinaryModuleFieldIsPropertyBit (uintptr)(1ul << 31)
+#endif
+
 void* ManagedBinaryModule::FindField(const ScriptingTypeHandle& typeHandle, const StringAnsiView& name)
 {
     const ScriptingType& type = typeHandle.GetType();
-    return type.ManagedClass ? type.ManagedClass->GetField(name.Get()) : nullptr;
+    void* result = type.ManagedClass ? type.ManagedClass->GetField(name.Get()) : nullptr;
+    if (!result && type.ManagedClass)
+    {
+        result = type.ManagedClass->GetProperty(name.Get());
+        if (result)
+            result = (void*)((uintptr)result | ManagedBinaryModuleFieldIsPropertyBit);
+    }
+    return result;
 }
 
 void ManagedBinaryModule::GetFieldSignature(void* field, ScriptingTypeFieldSignature& fieldSignature)
 {
 #if USE_CSHARP
-    const auto mField = (MField*)field;
-    fieldSignature.Name = mField->GetName();
-    fieldSignature.ValueType = MoveTemp(MUtils::UnboxVariantType(mField->GetType()));
-    fieldSignature.IsStatic = mField->IsStatic();
+    if ((uintptr)field & ManagedBinaryModuleFieldIsPropertyBit)
+    {
+        const auto mProperty = (MProperty*)((uintptr)field & ~ManagedBinaryModuleFieldIsPropertyBit);
+        fieldSignature.Name = mProperty->GetName();
+        fieldSignature.ValueType = MoveTemp(MUtils::UnboxVariantType(mProperty->GetType()));
+        fieldSignature.IsStatic = mProperty->IsStatic();
+    }
+    else
+    {
+        const auto mField = (MField*)field;
+        fieldSignature.Name = mField->GetName();
+        fieldSignature.ValueType = MoveTemp(MUtils::UnboxVariantType(mField->GetType()));
+        fieldSignature.IsStatic = mField->IsStatic();
+    }
 #endif
 }
 
 bool ManagedBinaryModule::GetFieldValue(void* field, const Variant& instance, Variant& result)
 {
 #if USE_CSHARP
-    const auto mField = (MField*)field;
+    bool isStatic;
+    MClass* parentClass;
+    StringAnsiView name;
+    if ((uintptr)field & ManagedBinaryModuleFieldIsPropertyBit)
+    {
+        const auto mProperty = (MProperty*)((uintptr)field & ~ManagedBinaryModuleFieldIsPropertyBit);
+        isStatic = mProperty->IsStatic();
+        parentClass = mProperty->GetParentClass();
+        name = mProperty->GetName();
+    }
+    else
+    {
+        const auto mField = (MField*)field;
+        isStatic = mField->IsStatic();
+        parentClass = mField->GetParentClass();
+        name = mField->GetName();
+    }
 
     // Get instance object
     MObject* instanceObject = nullptr;
-    if (!mField->IsStatic())
+    if (!isStatic)
     {
         // Box instance into C# object
         instanceObject = MUtils::BoxVariant(instance);
 
         // Validate instance
-        if (!instanceObject || !MCore::Object::GetClass(instanceObject)->IsSubClassOf(mField->GetParentClass()))
+        if (!instanceObject || !MCore::Object::GetClass(instanceObject)->IsSubClassOf(parentClass))
         {
             if (!instanceObject)
-                LOG(Error, "Failed to get field '{0}.{1}' without object instance", String(mField->GetParentClass()->GetFullName()), String(mField->GetName()));
+                LOG(Error, "Failed to get '{0}.{1}' without object instance", String(parentClass->GetFullName()), String(name));
             else
-                LOG(Error, "Failed to get field '{0}.{1}' with invalid object instance of type '{2}'", String(mField->GetParentClass()->GetFullName()), String(mField->GetName()), String(MUtils::GetClassFullname(instanceObject)));
+                LOG(Error, "Failed to get '{0}.{1}' with invalid object instance of type '{2}'", String(parentClass->GetFullName()), String(name), String(MUtils::GetClassFullname(instanceObject)));
             return true;
         }
     }
 
     // Get the value
-    MObject* resultObject = mField->GetValueBoxed(instanceObject);
+    MObject* resultObject;
+    if ((uintptr)field & ManagedBinaryModuleFieldIsPropertyBit)
+    {
+        const auto mProperty = (MProperty*)((uintptr)field & ~ManagedBinaryModuleFieldIsPropertyBit);
+        resultObject = mProperty->GetValue(instanceObject, nullptr);
+    }
+    else
+    {
+        const auto mField = (MField*)field;
+        resultObject = mField->GetValueBoxed(instanceObject);
+    }
     result = MUtils::UnboxVariant(resultObject);
     return false;
 #else
@@ -1375,29 +1426,54 @@ bool ManagedBinaryModule::GetFieldValue(void* field, const Variant& instance, Va
 bool ManagedBinaryModule::SetFieldValue(void* field, const Variant& instance, Variant& value)
 {
 #if USE_CSHARP
-    const auto mField = (MField*)field;
+    bool isStatic;
+    MClass* parentClass;
+    StringAnsiView name;
+    if ((uintptr)field & ManagedBinaryModuleFieldIsPropertyBit)
+    {
+        const auto mProperty = (MProperty*)((uintptr)field & ~ManagedBinaryModuleFieldIsPropertyBit);
+        isStatic = mProperty->IsStatic();
+        parentClass = mProperty->GetParentClass();
+        name = mProperty->GetName();
+    }
+    else
+    {
+        const auto mField = (MField*)field;
+        isStatic = mField->IsStatic();
+        parentClass = mField->GetParentClass();
+        name = mField->GetName();
+    }
 
     // Get instance object
     MObject* instanceObject = nullptr;
-    if (!mField->IsStatic())
+    if (!isStatic)
     {
         // Box instance into C# object
         instanceObject = MUtils::BoxVariant(instance);
 
         // Validate instance
-        if (!instanceObject || !MCore::Object::GetClass(instanceObject)->IsSubClassOf(mField->GetParentClass()))
+        if (!instanceObject || !MCore::Object::GetClass(instanceObject)->IsSubClassOf(parentClass))
         {
             if (!instanceObject)
-                LOG(Error, "Failed to set field '{0}.{1}' without object instance", String(mField->GetParentClass()->GetFullName()), String(mField->GetName()));
+                LOG(Error, "Failed to set '{0}.{1}' without object instance", String(parentClass->GetFullName()), String(name));
             else
-                LOG(Error, "Failed to set field '{0}.{1}' with invalid object instance of type '{2}'", String(mField->GetParentClass()->GetFullName()), String(mField->GetName()), String(MUtils::GetClassFullname(instanceObject)));
+                LOG(Error, "Failed to set '{0}.{1}' with invalid object instance of type '{2}'", String(parentClass->GetFullName()), String(name), String(MUtils::GetClassFullname(instanceObject)));
             return true;
         }
     }
 
     // Set the value
     bool failed = false;
-    mField->SetValue(instanceObject, MUtils::VariantToManagedArgPtr(value, mField->GetType(), failed));
+    if ((uintptr)field & ManagedBinaryModuleFieldIsPropertyBit)
+    {
+        const auto mProperty = (MProperty*)((uintptr)field & ~ManagedBinaryModuleFieldIsPropertyBit);
+        mProperty->SetValue(instanceObject, MUtils::BoxVariant(value), nullptr);
+    }
+    else
+    {
+        const auto mField = (MField*)field;
+        mField->SetValue(instanceObject, MUtils::VariantToManagedArgPtr(value, mField->GetType(), failed));
+    }
     return failed;
 #else
     return true;