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

#include "ParameterizeMeshTool.h"
#include "InteractiveToolManager.h"
#include "ToolBuilderUtil.h"
#include "ToolSetupUtil.h"
#include "ModelingToolTargetUtil.h"
#include "DynamicMesh/DynamicMesh3.h"
#include "FaceGroupUtil.h"
#include "ParameterizationOps/ParameterizeMeshOp.h"

#include "ExplicitUseGeometryMathTypes.h"		// using UE::Geometry::(math types)
using namespace UE::Geometry;

#define LOCTEXT_NAMESPACE "UParameterizeMeshTool"

/*
 * ToolBuilder
 */

USingleSelectionMeshEditingTool* UParameterizeMeshToolBuilder::CreateNewTool(const FToolBuilderState& SceneState) const
{
	UParameterizeMeshTool* NewTool = NewObject<UParameterizeMeshTool>(SceneState.ToolManager);
	return NewTool;
}

/*
 * Tool
 */


void UParameterizeMeshTool::Setup()
{
	UInteractiveTool::Setup();

	InputMesh = MakeShared<FDynamicMesh3, ESPMode::ThreadSafe>();
	*InputMesh = UE::ToolTarget::GetDynamicMeshCopy(Target);

	Preview = NewObject<UMeshOpPreviewWithBackgroundCompute>(this);
	Preview->Setup(this->TargetWorld, this);
	Preview->PreviewMesh->SetTangentsMode(EDynamicMeshComponentTangentsMode::AutoCalculated);
	Preview->PreviewMesh->ReplaceMesh(*InputMesh);
	Preview->ConfigureMaterials(UE::ToolTarget::GetMaterialSet(Target).Materials,
								ToolSetupUtil::GetDefaultWorkingMaterial(GetToolManager()));
	Preview->PreviewMesh->SetTransform((FTransform)UE::ToolTarget::GetLocalToWorldTransform(Target));

	Preview->OnMeshUpdated.AddLambda([this](UMeshOpPreviewWithBackgroundCompute* Op)
	{
		MaterialSettings->UpdateMaterials();
	});

	UE::ToolTarget::HideSourceObject(Target);

	// initialize our properties

	UVChannelProperties = NewObject<UMeshUVChannelProperties>(this);
	UVChannelProperties->RestoreProperties(this);
	UVChannelProperties->Initialize(InputMesh.Get(), false);
	UVChannelProperties->ValidateSelection(true);
	UVChannelProperties->WatchProperty(UVChannelProperties->UVChannel, [this](const FString& NewValue) 
	{
		MaterialSettings->UVChannel = UVChannelProperties->GetSelectedChannelIndex(true);
	});
	AddToolPropertySource(UVChannelProperties);

	Settings = NewObject<UParameterizeMeshToolProperties>(this);
	Settings->RestoreProperties(this);
	AddToolPropertySource(Settings);
	Settings->WatchProperty(Settings->Method, [&](EParameterizeMeshUVMethod) { OnMethodTypeChanged(); });


	UVAtlasProperties = NewObject<UParameterizeMeshToolUVAtlasProperties>(this);
	UVAtlasProperties->RestoreProperties(this);
	AddToolPropertySource(UVAtlasProperties);
	SetToolPropertySourceEnabled(UVAtlasProperties, false);

	XAtlasProperties = NewObject<UParameterizeMeshToolXAtlasProperties>(this);
	XAtlasProperties->RestoreProperties(this);
	AddToolPropertySource(XAtlasProperties);
	SetToolPropertySourceEnabled(XAtlasProperties, false);

	MaterialSettings = NewObject<UExistingMeshMaterialProperties>(this);
	MaterialSettings->MaterialMode = ESetMeshMaterialMode::Checkerboard;
	MaterialSettings->RestoreProperties(this, TEXT("ModelingUVTools"));
	AddToolPropertySource(MaterialSettings);
	// force update
	MaterialSettings->UpdateMaterials();
	Preview->OverrideMaterial = MaterialSettings->GetActiveOverrideMaterial();

	Preview->InvalidateResult();    // start compute

	SetToolDisplayName(LOCTEXT("ToolNameGlobal", "AutoUV"));
	GetToolManager()->DisplayMessage(
		LOCTEXT("OnStartTool_Global", "Automatically partition the selected Mesh into UV islands, flatten, and pack into a single UV chart"),
		EToolMessageLevel::UserNotification);
}

void UParameterizeMeshTool::OnPropertyModified(UObject* PropertySet, FProperty* Property)
{
	if (PropertySet != MaterialSettings)
	{
		Preview->InvalidateResult();
	}

	MaterialSettings->UpdateMaterials();
	Preview->OverrideMaterial = MaterialSettings->GetActiveOverrideMaterial();
}


void UParameterizeMeshTool::OnMethodTypeChanged()
{
	SetToolPropertySourceEnabled(UVAtlasProperties, Settings->Method == EParameterizeMeshUVMethod::UVAtlas);
	SetToolPropertySourceEnabled(XAtlasProperties, Settings->Method == EParameterizeMeshUVMethod::XAtlas);

	Preview->InvalidateResult();
}


void UParameterizeMeshTool::Shutdown(EToolShutdownType ShutdownType)
{
	UVChannelProperties->SaveProperties(this);
	Settings->SaveProperties(this);
	MaterialSettings->SaveProperties(this, TEXT("ModelingUVTools"));

	FDynamicMeshOpResult Result = Preview->Shutdown();
	
	// Restore (unhide) the source meshes
	UE::ToolTarget::ShowSourceObject(Target);

	if (ShutdownType == EToolShutdownType::Accept)
	{
		GetToolManager()->BeginUndoTransaction(LOCTEXT("ParameterizeMesh", "Auto UVs"));
		FDynamicMesh3* NewDynamicMesh = Result.Mesh.Get();
		if (ensure(NewDynamicMesh))
		{
			UE::ToolTarget::CommitDynamicMeshUVUpdate(Target, NewDynamicMesh);
		}
		GetToolManager()->EndUndoTransaction();
	}

}

void UParameterizeMeshTool::OnTick(float DeltaTime)
{
	Preview->Tick(DeltaTime);
}

bool UParameterizeMeshTool::CanAccept() const
{
	return Super::CanAccept() && Preview->HaveValidResult();
}

TUniquePtr<FDynamicMeshOperator> UParameterizeMeshTool::MakeNewOperator()
{
	FAxisAlignedBox3d MeshBounds = Preview->PreviewMesh->GetMesh()->GetBounds();
	TUniquePtr<FParameterizeMeshOp> ParameterizeMeshOp = MakeUnique<FParameterizeMeshOp>();

	ParameterizeMeshOp->InputMesh = InputMesh;
	ParameterizeMeshOp->UVLayer = UVChannelProperties->GetSelectedChannelIndex(true);
	ParameterizeMeshOp->Method = (EParamOpBackend)(int)Settings->Method;

	// uvatlas options
	ParameterizeMeshOp->Stretch   = UVAtlasProperties->ChartStretch;
	ParameterizeMeshOp->NumCharts = UVAtlasProperties->NumCharts;
	
	// xatlas options
	ParameterizeMeshOp->XAtlasMaxIterations = XAtlasProperties->MaxIterations;

	ParameterizeMeshOp->SetTransform(UE::ToolTarget::GetLocalToWorldTransform(Target));

	return ParameterizeMeshOp;
}



#undef LOCTEXT_NAMESPACE