urho3d/Source/Urho3D/AngelScript/APITemplates.h

// Copyright (c) 2008-2022 the Urho3D project
// License: MIT

#pragma once

#include "../AngelScript/Addons.h"
#include "../AngelScript/Script.h"
#include "../AngelScript/ScriptInstance.h"
#include "../Audio/SoundSource.h"
#include "../Core/Context.h"
#include "../Container/HashSet.h"
#include "../Container/Sort.h"
#include "../Graphics/Drawable.h"
#include "../Graphics/StaticModel.h"
#include "../GraphicsAPI/Texture.h"
#include "../IO/File.h"
#include "../IO/Log.h"
#include "../IO/VectorBuffer.h"
#include "../Resource/Resource.h"
#include "../Scene/Animatable.h"
#include "../Scene/Node.h"
#include "../UI/BorderImage.h"

#ifdef URHO3D_URHO2D
#include "../Urho2D/Drawable2D.h"
#endif

#include <AngelScript/angelscript.h>
#include <cstring>

#include "../AngelScript/RegistrationMacros.h"

#ifdef _MSC_VER
#pragma warning(push)
#pragma warning(disable:4505)
#endif

namespace Urho3D
{

class Camera;

/// Template function for Vector to array conversion.
template <class T> CScriptArray* VectorToArray(const Vector<T>& vector, const char* arrayName)
{
    Context* context = GetScriptContext();
    if (context)
    {
        asITypeInfo* type = context->GetSubsystem<Script>()->GetObjectType(arrayName);
        CScriptArray* arr = CScriptArray::Create(type, vector.Size());

        for (unsigned i = 0; i < arr->GetSize(); ++i)
            *(static_cast<T*>(arr->At(i))) = vector[i];

        return arr;
    }
    else
        return nullptr;
}

/// Template function for data buffer to array conversion.
template <class T> CScriptArray* BufferToArray(const T* buffer, unsigned size, const char* arrayName)
{
    Context* context = GetScriptContext();
    if (context)
    {
        asITypeInfo* type = context->GetSubsystem<Script>()->GetObjectType(arrayName);
        CScriptArray* arr = CScriptArray::Create(type, size);

        for (unsigned i = 0; i < arr->GetSize(); ++i)
            *(static_cast<T*>(arr->At(i))) = buffer[i];

        return arr;
    }
    else
        return nullptr;
}

/// Template function for Vector to handle array conversion.
template <class T> CScriptArray* VectorToHandleArray(const Vector<T*>& vector, const char* arrayName)
{
    Context* context = GetScriptContext();
    if (context)
    {
        asITypeInfo* type = context->GetSubsystem<Script>()->GetObjectType(arrayName);
        CScriptArray* arr = CScriptArray::Create(type, vector.Size());

        for (unsigned i = 0; i < arr->GetSize(); ++i)
        {
            // Increment reference count for storing in the array
            T* ptr = vector[i];
            if (ptr)
                ptr->AddRef();
            *(static_cast<T**>(arr->At(i))) = ptr;
        }

        return arr;
    }
    else
        return nullptr;
}

/// Template function for shared pointer Vector to handle array conversion.
template <class T> CScriptArray* VectorToHandleArray(const Vector<SharedPtr<T>>& vector, const char* arrayName)
{
    Context* context = GetScriptContext();

    if (!context)
        return nullptr;

    asITypeInfo* type = context->GetSubsystem<Script>()->GetObjectType(arrayName);
    CScriptArray* arr = CScriptArray::Create(type, vector.Size());

    for (unsigned i = 0; i < arr->GetSize(); ++i)
    {
        // Increment reference count for storing in the array
        T* ptr = vector[i];
        if (ptr)
            ptr->AddRef();
        *(static_cast<T**>(arr->At(i))) = ptr;
    }

    return arr;
}

/// Template function for array to Vector conversion.
template <class T> Vector<T> ArrayToVector(CScriptArray* arr)
{
    Vector<T> dest(arr ? arr->GetSize() : 0);
    if (arr)
    {
        for (unsigned i = 0; i < arr->GetSize(); ++i)
            dest[i] = *static_cast<T*>(arr->At(i));
    }
    return dest;
}

template <class T> Vector<SharedPtr<T>> HandleArrayToVector(CScriptArray* arr)
{
    Vector<T*> rawPtrs = ArrayToVector<T*>(arr);
    Vector<SharedPtr<T>> result(rawPtrs.Size());
    for (unsigned i = 0; i < rawPtrs.Size(); ++i)
        result[i] = SharedPtr<T>(rawPtrs[i]);
    return result;
}

/// Template function for dynamic cast between two script classes.
template <class From, class To> To* RefCast(From* from)
{
    if (!from)
        return nullptr;

    return dynamic_cast<To*>(from);
}

/// Template function for registering casts between base and subclass.
// https://www.angelcode.com/angelscript/sdk/docs/manual/doc_adv_class_hierarchy.html
template <class BaseType, class DerivedType> void RegisterSubclass(asIScriptEngine* engine, const char* baseClassName, const char* derivedClassName)
{
    if (!strcmp(baseClassName, derivedClassName))
        return;
    String declReturnBase = String(baseClassName) +
                            ((engine->GetTypeInfoByName(baseClassName)->GetFlags() & asOBJ_NOCOUNT) ? "@" : "@+") +
                            " opImplCast()";
    engine->RegisterObjectMethod(derivedClassName, declReturnBase.CString(), AS_FUNCTION_OBJLAST((RefCast<DerivedType, BaseType>)), AS_CALL_CDECL_OBJLAST);

    String declReturnBaseConst("const " + declReturnBase + " const");
    engine->RegisterObjectMethod(derivedClassName, declReturnBaseConst.CString(), AS_FUNCTION_OBJLAST((RefCast<DerivedType, BaseType>)), AS_CALL_CDECL_OBJLAST);

    //String declReturnDerived(String(derivedClassName) + "@+ opCast()");
    String declReturnDerived(String(derivedClassName) +
              ((engine->GetTypeInfoByName(derivedClassName)->GetFlags() & asOBJ_NOCOUNT) ? "@" : "@+") +
              " opImplCast()");
    engine->RegisterObjectMethod(baseClassName, declReturnDerived.CString(), AS_FUNCTION_OBJLAST((RefCast<BaseType, DerivedType>)), AS_CALL_CDECL_OBJLAST);

    //String declReturnDerivedConst("const " + String(derivedClassName) + "@+ opCast() const");
    String declReturnDerivedConst("const " + declReturnDerived + " const");
    engine->RegisterObjectMethod(baseClassName, declReturnDerivedConst.CString(), AS_FUNCTION_OBJLAST((RefCast<BaseType, DerivedType>)), AS_CALL_CDECL_OBJLAST);
}

// ================================================================================

// TODO Incorrect

// Template function for dynamic cast between two script value classes.
template <class SrcClass, class DstClass> DstClass* ValCast(SrcClass* src)
{
    if (!src)
        return nullptr;

    return dynamic_cast<DstClass*>(src);
}

template <class baseClass, class subclass> void RegisterSubclassValue(asIScriptEngine* engine, const char* baseClassName, const char* subclassName)
{
    assert(!strcmp(baseClassName, subclassName));

    String decl(String(baseClassName) + " opImplConvCast() const");
    engine->RegisterObjectMethod(subclassName, decl.CString(), asFUNCTION((ValCast<subclass, baseClass>)), asCALL_CDECL_OBJLAST);
}

// ================================================================================

// https://en.cppreference.com/w/cpp/types/enable_if

// We need detect implicitly-declared assign operator on complie time because Doxygen not povide this information
template<typename classType, typename std::enable_if<std::is_copy_assignable<classType>::value, int>::type = 0>
void RegisterImplicitlyDeclaredAssignOperatorIfPossible(asIScriptEngine* engine, const String& className)
{
    String decl = className + "& opAssign(const " + className + "&in)";
    engine->RegisterObjectMethod(className.CString(), decl.CString(), AS_METHODPR(classType, operator=, (const classType&), classType&), AS_CALL_THISCALL);
}

// This empty function need to prevent build errors when classType have no assing operator
template<typename classType, typename std::enable_if<!std::is_copy_assignable<classType>::value, int>::type = 0>
void RegisterImplicitlyDeclaredAssignOperatorIfPossible(asIScriptEngine* engine, const String& className)
{
}

// ================================================================================
// To keep Xcode LLVM/Clang happy - it erroneously warns on unused functions defined below which are actually being referenced in the code
#if __clang__
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wunused-function"
#endif

template <class T> T* ConstructObject()
{
    auto* object = new T(GetScriptContext());
    object->AddRef();
    return object;
}

template <class T> T* ConstructNamedObject(const String& name)
{
    auto* object = new T(GetScriptContext());
    object->AddRef();
    object->SetName(name);
    return object;
}

/// Template function for registering a default constructor for a class derived from Object.
template <class T> void RegisterObjectConstructor(asIScriptEngine* engine, const char* className)
{
    String declFactory(String(className) + "@ f()");
    engine->RegisterObjectBehaviour(className, asBEHAVE_FACTORY, declFactory.CString(), AS_FUNCTION(ConstructObject<T>), AS_CALL_CDECL);
}

/// Template function for registering a named constructor for a class derived from Object.
template <class T> void RegisterNamedObjectConstructor(asIScriptEngine* engine, const char* className)
{
    String declFactoryWithName(String(className) + "@ f(const String&in)");
    engine->RegisterObjectBehaviour(className, asBEHAVE_FACTORY, declFactoryWithName.CString(), AS_FUNCTION(ConstructNamedObject<T>), AS_CALL_CDECL);
}

#if __clang__
#pragma clang diagnostic pop
#endif

}

#ifdef _MSC_VER
#pragma warning(pop)
#endif