// Copyright Epic Games, Inc. All Rights Reserved.

#pragma once

#include "MuR/Ptr.h"
#include "MuR/Model.h"
#include "MuR/Parameters.h"
#include "Engine/SkeletalMesh.h"
#include "CoreMinimal.h"

#include "CustomizableObjectSkeletalMesh.generated.h"

#define UE_API CUSTOMIZABLEOBJECT_API

namespace mu
{
	typedef uint64 FResourceID;
}

class UCustomizableObjectInstance;
class UCustomizableObject;
class UCustomizableInstancePrivate;
class FUpdateContextPrivate;
class FCustomizableObjectMeshStreamIn;
struct FModelStreamableBulkData;


/**
 * CustomizableObjectSkeletalMesh is a class inheriting from USkeletalMesh with the sole purpose of allowing skeletal meshes generated by Mutable
 * to stream-in Mesh LODs. 
 */
UCLASS(MinimalAPI)
class UCustomizableObjectSkeletalMesh : public USkeletalMesh
{
	GENERATED_BODY()

	friend FCustomizableObjectMeshStreamIn;
	friend UCustomizableInstancePrivate;
	
	UE_API void InitMutableStreamingData(const TSharedRef<FUpdateContextPrivate>& InOperationData, const FName& ComponentName, const int32 FirstLOD, const int32 LODCount);

	//~ Begin UStreamableRenderAsset Interface.
	UE_API virtual bool StreamIn(int32 NewMipCount, bool bHighPrio) override;
	//~ End UStreamableRenderAsset Interface.

	FString CustomizableObjectPathName;

	TSharedPtr<FModelStreamableBulkData> ModelStreamableBulkData;

	TSharedPtr<mu::FModel, ESPMode::ThreadSafe> Model;
	
	/** Instance parameters at the time of creation. */
	TSharedPtr<mu::FParameters> Parameters;
	int32 State = -1;

	/** Mesh IDs per LOD */
	TArray<mu::FResourceID> MeshIDs;
	TArray<TArray<uint32>> SurfaceIDs;
	TArray<TPair<uint32, FName>> SkinWeightProfileIDs;
};

#undef UE_API