Add ScriptingEnum utility with useful features for C++ scripting

Source/Engine/Scripting/Enums.h

@@ -0,0 +1,65 @@
+// Copyright (c) 2012-2021 Wojciech Figat. All rights reserved.
+
+#pragma once
+
+#include "ScriptingType.h"
+#include "Engine/Core/Types/String.h"
+
+// Utilities for using enums types (declared in scripting with API_ENUM).
+template<class EnumType>
+class ScriptingEnum
+{
+public:
+    // Gets the list with enum items (the last item Name is null)
+    static const ScriptingType::EnumItem* GetItems()
+    {
+        const ScriptingTypeHandle typeHandle = StaticType<EnumType>();
+        if (typeHandle)
+        {
+            const ScriptingType& type = typeHandle.GetType();
+            if (type.Type == ScriptingTypes::Enum)
+                return type.Enum.Items;
+        }
+        return nullptr;
+    }
+
+    // Gets the name of the enum value or null if invalid
+    static const char* GetName(EnumType value)
+    {
+        if (const auto items = GetItems())
+        {
+            for (int32 i = 0; items[i].Name; i++)
+            {
+                if (items[i].Value == (uint64)value)
+                    return items[i].Name;
+            }
+        }
+        return nullptr;
+    }
+
+    // Gets the name of the enum value or empty string if invalid
+    static String ToString(EnumType value)
+    {
+        return String(GetName(value));
+    }
+
+    // Gets the value of the enum based on the name.
+    static EnumType FromString(const StringAnsiView& name)
+    {
+        if (const auto items = GetItems())
+        {
+            for (int32 i = 0; items[i].Name; i++)
+            {
+                if (name == items[i].Name)
+                    return (EnumType)items[i].Value;
+            }
+        }
+        return (EnumType)0;
+    }
+
+    // Gets the value of the enum based on the name.
+    static EnumType FromString(const StringView& name)
+    {
+        return FromString(StringAnsi(name));
+    }
+};