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

#pragma once

#include "HAL/Platform.h"
#include "UObject/NameTypes.h"
#include "Containers/Map.h"
#include "Containers/Array.h"
#include "UObject/ObjectPtr.h"
#include "BoneIndices.h"

class USkeletalMesh;
namespace mu { class FMeshBufferSet; }

/** Publicly accessible methods designed to prepare the Mutable Mesh buffers with the internal structure  required by Unreal and
 * our systems to be able to work with the mesh owning those buffers.
 */
namespace  MutableMeshBufferUtils
{
	// VERTEX BUFFERS
	
	/** Determines the max amount of channels that can inhabit a Texture Coordinate buffer. */
	constexpr int32 MaxTexCordChannelCount = 4;
	
	/**
	 * Sets up all the channels that ought to be part of the Vertex Position Buffer of the Mutable mesh owning the provided MeshBufferSet
	 * @param InCurrentVertexBuffer Index of the Vertex Buffer being set up inside the OutTargetVertexBuffers.
	 * @param OutTargetVertexBuffers Mesh buffer to be set up. 
	 */
	CUSTOMIZABLEOBJECT_API void SetupVertexPositionsBuffer(const int32& InCurrentVertexBuffer, mu::FMeshBufferSet& OutTargetVertexBuffers);

	/**
	 * Sets up all the channels that ought to be part of the Vertex Tangent Buffer of the Mutable mesh owning the provided MeshBufferSet
	 * @param InCurrentVertexBuffer Index of the Vertex Buffer being set up inside the OutTargetVertexBuffers.
	 * @param OutTargetVertexBuffers Mesh buffer to be set up. 
	 */
	CUSTOMIZABLEOBJECT_API void SetupTangentBuffer(const int32& InCurrentVertexBuffer, mu::FMeshBufferSet& OutTargetVertexBuffers);

	/**
	 * Sets up all the channels that ought to be part of the Vertex Texture Coordinates Buffer of the Mutable mesh owning the provided MeshBufferSet
	 * @param InCurrentVertexBuffer Index of the Vertex Buffer being set up inside the OutTargetVertexBuffers.
	 * @param InChannelCount Determines the amount of TexCord channels able to be added onto the buffer.
	 * @param OutTargetVertexBuffers Mesh buffer to be set up. 
	 * @param InTextureSemanticIndicesOverride (Optional) If you are certain of the texture semantic indices that should be used populate this argument, if not, leave it as null
	 */
	CUSTOMIZABLEOBJECT_API void SetupTexCoordinatesBuffer(const int32& InCurrentVertexBuffer,const int32& InChannelCount, bool bHighPrecision, mu::FMeshBufferSet& OutTargetVertexBuffers, const int32* InTextureSemanticIndicesOverride = nullptr);

	/**
	 * Sets up all the channels that ought to be part of the Vertex Skin Buffer of the Mutable mesh owning the provided MeshBufferSet
	 * @param InCurrentVertexBuffer Index of the Vertex Buffer being set up inside the OutTargetVertexBuffers.
	 * @param MaxBoneIndexTypeSizeBytes Maximum size of the vertex bone index type.
	 * @param MaxNumBonesPerVertex Amount of bone influences a vertex can have.
	 * @param OutTargetVertexBuffers Mesh buffer to be set up. 
	 */
	CUSTOMIZABLEOBJECT_API void SetupSkinBuffer(const int32& InCurrentVertexBuffer,const int32& MaxBoneIndexTypeSizeBytes, const int32& MaxBoneWeightTypeSizeBytes,
		const int32& MaxNumBonesPerVertex, mu::FMeshBufferSet& OutTargetVertexBuffers);
	
	/**
	 * Sets up all the channels that ought to be part of the Vertex Color Buffer of the Mutable mesh owning the provided MeshBufferSet
	 * @param InCurrentVertexBuffer Index of the Vertex Buffer being set up inside the OutTargetVertexBuffers.
	 * @param OutTargetVertexBuffers Mesh buffer to be set up. 
	 */
	CUSTOMIZABLEOBJECT_API void SetupVertexColorBuffer(const int32& InCurrentVertexBuffer, mu::FMeshBufferSet& OutTargetVertexBuffers);

	// INDEX BUFFERS

	/**
	 * Sets up all the channels that ought to be part of the Index Buffer of the Mutable mesh owning the provided MeshBufferSet
	 * @param OutTargetIndexBuffers Index buffer to be set up. 
	 */
	CUSTOMIZABLEOBJECT_API void SetupIndexBuffer(mu::FMeshBufferSet& OutTargetIndexBuffers);

	/**
	 * Sets up all the channels that ought to be part of the Vertex SkinWeightProfile Buffer of the Mutable mesh owning the provided MeshBufferSet
	 * @param InCurrentVertexBuffer Index of the Vertex Buffer being set up inside the OutTargetVertexBuffers.
	 * @param MaxBoneIndexTypeSizeBytes Maximum size of the vertex bone index type.
	 * @param MaxBoneWeightTypeSizeBytes Maximum size of the vertex bone weight type.
	 * @param MaxNumBonesPerVertex Amount of bone influences a vertex can have.
	 * @param SemanticsIndex External Id that identifies a SkinWeightProfile.
	 * @param OutTargetVertexBuffers Mesh buffer to be set up.
	 */
	CUSTOMIZABLEOBJECT_API void SetupSkinWeightProfileBuffer(const int32& InCurrentVertexBuffer, const int32& MaxBoneIndexTypeSizeBytes,const int32& MaxBoneWeightTypeSizeBytes, const int32& MaxNumBonesPerVertex,
		const int32 SemanticsIndex, mu::FMeshBufferSet& OutTargetVertexBuffers);

}