// Copyright 1998-2017 Epic Games, Inc. All Rights Reserved.

#include "VREditorMotionControllerInteractor.h"
#include "GenericPlatform/GenericApplicationMessageHandler.h"
#include "Misc/App.h"
#include "Framework/Application/SlateApplication.h"
#include "Components/StaticMeshComponent.h"
#include "GenericPlatform/IInputInterface.h"
#include "Components/PointLightComponent.h"
#include "Engine/StaticMesh.h"
#include "Materials/MaterialInstance.h"
#include "Materials/MaterialInstanceDynamic.h"
#include "Engine/StaticMeshSocket.h"
#include "ViewportWorldInteraction.h"
#include "VREditorPlacement.h"
#include "VREditorMode.h"
#include "VREditorUISystem.h"
#include "VREditorFloatingText.h"
#include "VREditorDockableWindow.h"
#include "VREditorRadialFloatingUI.h"
#include "UObject/Package.h"
#include "Engine/Engine.h"
#include "EngineGlobals.h"
#include "IMotionController.h"
#include "IHeadMountedDisplay.h"
#include "MotionControllerComponent.h"
#include "Features/IModularFeatures.h"
#include "Engine/Selection.h"
#include "VREditorWidgetComponent.h"
#include "LevelEditorActions.h"
#include "Components/SplineComponent.h"
#include "Components/SplineMeshComponent.h"
#include "DrawDebugHelpers.h"
#include "VREditorActions.h"
#include "VREditorAssetContainer.h"
#include "VRModeSettings.h"

namespace VREd
{
	//Laser
	static FAutoConsoleVariable OculusLaserPointerRotationOffset( TEXT( "VI.OculusLaserPointerRotationOffset" ), 0.0f, TEXT( "How much to rotate the laser pointer (pitch) relative to the forward vector of the controller (Oculus)" ) );
	static FAutoConsoleVariable ViveLaserPointerRotationOffset( TEXT( "VI.ViveLaserPointerRotationOffset" ), /* -57.8f */ 0.0f, TEXT( "How much to rotate the laser pointer (pitch) relative to the forward vector of the controller (Vive)" ) );
	static FAutoConsoleVariable OculusLaserPointerStartOffset( TEXT( "VI.OculusLaserPointerStartOffset" ), 2.8f, TEXT( "How far to offset the start of the laser pointer to avoid overlapping the hand mesh geometry (Oculus)" ) );
	static FAutoConsoleVariable ViveLaserPointerStartOffset( TEXT( "VI.ViveLaserPointerStartOffset" ), 1.25f /* 8.5f */, TEXT( "How far to offset the start of the laser pointer to avoid overlapping the hand mesh geometry (Vive)" ) );

	// Laser visuals
	static FAutoConsoleVariable LaserPointerRadius( TEXT( "VREd.LaserPointerRadius" ), .5f, TEXT( "Radius of the laser pointer line" ) );
	static FAutoConsoleVariable LaserPointerHoverBallRadius( TEXT( "VREd.LaserPointerHoverBallRadius" ), 1.0f, TEXT( "Radius of the visual cue for a hovered object along the laser pointer ray" ) );
	static FAutoConsoleVariable LaserPointerLightPullBackDistance( TEXT( "VREd.LaserPointerLightPullBackDistance" ), 2.5f, TEXT( "How far to pull back our little hover light from the impact surface" ) );
	static FAutoConsoleVariable LaserPointerLightRadius( TEXT( "VREd.LaserPointLightRadius" ), 10.0f, TEXT( "How big our hover light is" ) );
	static FAutoConsoleVariable LaserRadiusScaleWhenOverUI( TEXT( "VREd.LaserRadiusScaleWhenOverUI" ), 0.25f, TEXT( "How much to scale down the size of the laser pointer radius when over UI" ) );
	static FAutoConsoleVariable HoverBallRadiusScaleWhenOverUI(TEXT("VREd.HoverBallRadiusScaleWhenOverUI"), 0.4f, TEXT("How much to scale down the size of the hover ball when over UI"));
	//Trigger
	static FAutoConsoleVariable TriggerDeadZone_Vive( TEXT( "VI.TriggerDeadZone_Vive" ), 0.01f, TEXT( "Trigger dead zone.  The trigger must be fully released before we'll trigger a new 'light press'" ) );
	static FAutoConsoleVariable TriggerDeadZone_Rift( TEXT( "VI.TriggerDeadZone_Rift" ), 0.15f, TEXT( "Trigger dead zone.  The trigger must be fully released before we'll trigger a new 'light press'" ) );
	static FAutoConsoleVariable TriggerFullyPressedThreshold_Vive( TEXT( "VI.TriggerFullyPressedThreshold_Vive" ), 0.90f, TEXT( "Minimum trigger threshold before we consider the trigger 'fully pressed'" ) );
	static FAutoConsoleVariable TriggerFullyPressedThreshold_Rift( TEXT( "VI.TriggerFullyPressedThreshold_Rift" ), 0.99f, TEXT( "Minimum trigger threshold before we consider the trigger 'fully pressed'" ) );

	static FAutoConsoleVariable TrackpadAbsoluteDragSpeed( TEXT( "VREd.TrackpadAbsoluteDragSpeed" ), 40.0f, TEXT( "How fast objects move toward or away when you drag on the touchpad while carrying them" ) );
	static FAutoConsoleVariable TrackpadRelativeDragSpeed( TEXT( "VREd.TrackpadRelativeDragSpeed" ), 8.0f, TEXT( "How fast objects move toward or away when you hold a direction on an analog stick while carrying them" ) );
	static FAutoConsoleVariable InvertTrackpadVertical( TEXT( "VREd.InvertTrackpadVertical" ), 1, TEXT( "Toggles inverting the touch pad vertical axis" ) );
	static FAutoConsoleVariable MinVelocityForInertia( TEXT( "VREd.MinVelocityForMotionControllerInertia" ), 1.0f, TEXT( "Minimum velocity (in cm/frame in unscaled room space) before inertia will kick in when releasing objects (or the world)" ) );
	static FAutoConsoleVariable MinTrackpadOffsetBeforeRadialMenu( TEXT( "VREd.MinTrackpadOffsetBeforeRadialMenu" ), 0.5f, TEXT( "How far you have to hold the trackpad upward before you can placing objects instantly by pulling the trigger" ) );

	static FAutoConsoleVariable ShowControllerHelpLabels( TEXT( "VREd.ShowControllerHelpLabels" ), 0, TEXT( "Enables help text overlay when controllers are near the viewer" ) );
	static FAutoConsoleVariable HelpLabelFadeDuration( TEXT( "VREd.HelpLabelFadeDuration" ), 0.4f, TEXT( "Duration to fade controller help labels in and out" ) );
	static FAutoConsoleVariable HelpLabelFadeDistance( TEXT( "VREd.HelpLabelFadeDistance" ), 30.0f, TEXT( "Distance at which controller help labels should appear (in cm)" ) );

	static FAutoConsoleVariable MinJoystickOffsetBeforeFlick(TEXT("VREd.MinJoystickOffsetBeforeFlick"), 0.4f, TEXT("Dead zone for flick actions on the motion controller"));
	
	static FAutoConsoleVariable SequencerScrubMax(TEXT("VREd.SequencerScrubMax"), 2.0f, TEXT("Max fast forward or fast reverse magnitude"));

}

const FName UVREditorMotionControllerInteractor::TrackpadPositionX = FName( "TrackpadPositionX" );
const FName UVREditorMotionControllerInteractor::TrackpadPositionY = FName( "TrackpadPositionY" );
const FName UVREditorMotionControllerInteractor::TriggerAxis = FName( "TriggerAxis" );
const FName UVREditorMotionControllerInteractor::MotionController_Left_PressedTriggerAxis = FName( "MotionController_Left_PressedTriggerAxis" );
const FName UVREditorMotionControllerInteractor::MotionController_Right_PressedTriggerAxis = FName( "MotionController_Right_PressedTriggerAxis" );
const FName UVREditorMotionControllerInteractor::MotionController_Left_FullyPressedTriggerAxis = FName( "MotionController_Left_FullyPressedTriggerAxis" );
const FName UVREditorMotionControllerInteractor::MotionController_Right_FullyPressedTriggerAxis = FName( "MotionController_Right_FullyPressedTriggerAxis" );

namespace VREditorKeyNames
{
	// @todo vreditor input: Ideally these would not be needed, but SteamVR fires off it's "trigger pressed" event
	// well before the trigger is fully down (*click*)
	static const FName MotionController_Left_PressedTriggerAxis( "MotionController_Left_PressedTriggerAxis" );
	static const FName MotionController_Right_PressedTriggerAxis( "MotionController_Right_PressedTriggerAxis" );
	static const FName MotionController_Left_FullyPressedTriggerAxis( "MotionController_Left_FullyPressedTriggerAxis" );
	static const FName MotionController_Right_FullyPressedTriggerAxis( "MotionController_Right_FullyPressedTriggerAxis" );
}

namespace SteamVRControllerKeyNames
{
	static const FGamepadKeyNames::Type Touch0( "Steam_Touch_0" );
	static const FGamepadKeyNames::Type Touch1( "Steam_Touch_1" );
}


#define LOCTEXT_NAMESPACE "VREditor"

UVREditorMotionControllerInteractor::UVREditorMotionControllerInteractor( const FObjectInitializer& Initializer ) :
	Super( Initializer ),
	MotionControllerComponent( nullptr ),
	HandMeshComponent( nullptr ),
	LaserPointerMID( nullptr ),
	TranslucentLaserPointerMID( nullptr ),
	HoverMeshComponent( nullptr ),
	HoverPointLightComponent( nullptr ),
	HandMeshMID( nullptr ),
	ControllerHandSide( EControllerHand::Pad ),
	bHaveMotionController( false ),
	bIsTriggerFullyPressed( false ),
	bIsTriggerPressed( false ),
	bHasTriggerBeenReleasedSinceLastPress( true ),
	bIsTouchingTrackpad( false ),
	bIsPressingTrackpad( false ),
	TrackpadPosition( FVector2D::ZeroVector ),
	LastTrackpadPosition( FVector2D::ZeroVector ),
	bIsTrackpadPositionValid { false, false },
	LastTrackpadPositionUpdateTime( FTimespan::MinValue() ),
	LastActiveTrackpadUpdateTime( FTimespan::MinValue() ), 
	bForceShowLaser(false),
	ForceLaserColor(),
	bIsScrubbingSequence(false),
	LastSwipe(ETouchSwipeDirection::None),
	InitialTouchPosition(FVector2D::ZeroVector)
{
}


UVREditorMotionControllerInteractor::~UVREditorMotionControllerInteractor()
{
	Shutdown();
}


void UVREditorMotionControllerInteractor::Init( class UVREditorMode* InVRMode )
{
	Super::Init( InVRMode );
	bHaveMotionController = true;

	const EHMDDeviceType::Type HMDDeviceType = GetVRMode().GetHMDDeviceType();
	// Setup keys
	if ( ControllerHandSide == EControllerHand::Left )
	{
		AddKeyAction( EKeys::MotionController_Left_Grip1, FViewportActionKeyInput( ViewportWorldActionTypes::WorldMovement ) );
		AddKeyAction( UVREditorMotionControllerInteractor::MotionController_Left_FullyPressedTriggerAxis, FViewportActionKeyInput( ViewportWorldActionTypes::SelectAndMove_FullyPressed ) );
		AddKeyAction( UVREditorMotionControllerInteractor::MotionController_Left_PressedTriggerAxis, FViewportActionKeyInput( ViewportWorldActionTypes::SelectAndMove ) );
		AddKeyAction( SteamVRControllerKeyNames::Touch0, FViewportActionKeyInput( VRActionTypes::Touch ) );
		AddKeyAction( EKeys::MotionController_Left_TriggerAxis, FViewportActionKeyInput( UVREditorMotionControllerInteractor::TriggerAxis ) );
		AddKeyAction( EKeys::MotionController_Left_Thumbstick_X, FViewportActionKeyInput( UVREditorMotionControllerInteractor::TrackpadPositionX ) );
		AddKeyAction( EKeys::MotionController_Left_Thumbstick_Y, FViewportActionKeyInput( UVREditorMotionControllerInteractor::TrackpadPositionY ) );
		AddKeyAction( EKeys::MotionController_Left_Thumbstick, FViewportActionKeyInput( VRActionTypes::ConfirmRadialSelection ) );

		if ( HMDDeviceType == EHMDDeviceType::DT_SteamVR )
		{
			AddKeyAction( EKeys::MotionController_Left_Shoulder, FViewportActionKeyInput( VRActionTypes::Modifier ) );
		}
		else if( HMDDeviceType == EHMDDeviceType::DT_OculusRift )
		{
			AddKeyAction( EKeys::MotionController_Left_FaceButton1, FViewportActionKeyInput( VRActionTypes::Modifier ) );
			AddKeyAction( EKeys::MotionController_Left_FaceButton2, FViewportActionKeyInput( VRActionTypes::Modifier2 ) );
		}
	}
	else if ( ControllerHandSide == EControllerHand::Right )
	{
		AddKeyAction( EKeys::MotionController_Right_Grip1, FViewportActionKeyInput( ViewportWorldActionTypes::WorldMovement ) );
		AddKeyAction( UVREditorMotionControllerInteractor::MotionController_Right_FullyPressedTriggerAxis, FViewportActionKeyInput( ViewportWorldActionTypes::SelectAndMove_FullyPressed ) );
		AddKeyAction( UVREditorMotionControllerInteractor::MotionController_Right_PressedTriggerAxis, FViewportActionKeyInput( ViewportWorldActionTypes::SelectAndMove ) );
		AddKeyAction( SteamVRControllerKeyNames::Touch1, FViewportActionKeyInput( VRActionTypes::Touch ) );
		AddKeyAction( EKeys::MotionController_Right_TriggerAxis, FViewportActionKeyInput( UVREditorMotionControllerInteractor::TriggerAxis ) );
		AddKeyAction( EKeys::MotionController_Right_Thumbstick_X, FViewportActionKeyInput( UVREditorMotionControllerInteractor::TrackpadPositionX ) );
		AddKeyAction( EKeys::MotionController_Right_Thumbstick_Y, FViewportActionKeyInput( UVREditorMotionControllerInteractor::TrackpadPositionY ) );
		AddKeyAction( EKeys::MotionController_Right_Thumbstick, FViewportActionKeyInput( VRActionTypes::ConfirmRadialSelection ) );

		if ( HMDDeviceType == EHMDDeviceType::DT_SteamVR )
		{
			AddKeyAction( EKeys::MotionController_Right_Shoulder, FViewportActionKeyInput( VRActionTypes::Modifier ) );
		}
		else if ( HMDDeviceType == EHMDDeviceType::DT_OculusRift )
		{
			AddKeyAction( EKeys::MotionController_Right_FaceButton1, FViewportActionKeyInput( VRActionTypes::Modifier ) );
			AddKeyAction( EKeys::MotionController_Right_FaceButton2, FViewportActionKeyInput( VRActionTypes::Modifier2 ) );
		}
	}
}


float UVREditorMotionControllerInteractor::GetSlideDelta()
{
	return GetTrackpadSlideDelta();
}


void UVREditorMotionControllerInteractor::SetupComponent( AActor* OwningActor )
{
	// Setup a motion controller component.  This allows us to take advantage of late frame updates, so
	// our motion controllers won't lag behind the HMD
	{
		MotionControllerComponent = NewObject<UMotionControllerComponent>( OwningActor );
		OwningActor->AddOwnedComponent( MotionControllerComponent );
		MotionControllerComponent->SetupAttachment( OwningActor->GetRootComponent() );
		MotionControllerComponent->RegisterComponent();

		MotionControllerComponent->SetMobility( EComponentMobility::Movable );
		MotionControllerComponent->SetCollisionEnabled( ECollisionEnabled::NoCollision );

		MotionControllerComponent->Hand = ControllerHandSide;

		// @todo vreditor: Reenable late frame updates after we've sorted out why they cause popping artifacts on Rift
		MotionControllerComponent->bDisableLowLatencyUpdate = true;
	}

	const UVREditorAssetContainer& AssetContainer = VRMode->GetAssetContainer();

	// Hand mesh
	{
		HandMeshComponent = VRMode->CreateMotionControllerMesh( OwningActor, MotionControllerComponent ); 
		check( HandMeshComponent != nullptr );
		HandMeshComponent->SetCastShadow(false);
		HandMeshComponent->SetCollisionEnabled(ECollisionEnabled::PhysicsOnly);
		HandMeshComponent->SetCollisionResponseToAllChannels(ECR_Block);

		UMaterialInterface* HandMeshMaterial = GetVRMode().GetHMDDeviceType() == EHMDDeviceType::DT_SteamVR ? AssetContainer.VivePreControllerMaterial : AssetContainer.OculusControllerMaterial;
		check( HandMeshMaterial != nullptr );
		HandMeshMID = UMaterialInstanceDynamic::Create( HandMeshMaterial, GetTransientPackage() );
		check( HandMeshMID != nullptr );
		HandMeshComponent->SetMaterial( 0, HandMeshMID );
	}

	{
		UMaterialInterface* LaserPointerMaterial = AssetContainer.LaserPointerMaterial;
		check(LaserPointerMaterial != nullptr);
		LaserPointerMID = UMaterialInstanceDynamic::Create(LaserPointerMaterial, GetTransientPackage());
		check(LaserPointerMID != nullptr);

		UMaterialInterface* TranslucentLaserPointerMaterial = AssetContainer.LaserPointerTranslucentMaterial;
		check(TranslucentLaserPointerMaterial != nullptr);
		TranslucentLaserPointerMID = UMaterialInstanceDynamic::Create(TranslucentLaserPointerMaterial, GetTransientPackage());
		check(TranslucentLaserPointerMID != nullptr);
	}

	// Hover cue for laser pointer
	{
		HoverMeshComponent = NewObject<UStaticMeshComponent>( OwningActor );
		OwningActor->AddOwnedComponent( HoverMeshComponent );
		HoverMeshComponent->SetupAttachment( OwningActor->GetRootComponent() );
		HoverMeshComponent->RegisterComponent();

		UStaticMesh* HoverMesh = AssetContainer.LaserPointerHoverMesh;
		check( HoverMesh != nullptr );
		HoverMeshComponent->SetStaticMesh( HoverMesh );
		HoverMeshComponent->SetMobility( EComponentMobility::Movable );
		HoverMeshComponent->SetCollisionEnabled( ECollisionEnabled::NoCollision );
		HoverMeshComponent->SetCastShadow(false);

		HoverMeshComponent->SetMaterial( 0, LaserPointerMID );
		HoverMeshComponent->SetMaterial( 1, TranslucentLaserPointerMID );

		// Add a light!
		{
			HoverPointLightComponent = NewObject<UPointLightComponent>( OwningActor );
			OwningActor->AddOwnedComponent( HoverPointLightComponent );
			HoverPointLightComponent->SetupAttachment( HoverMeshComponent );
			HoverPointLightComponent->RegisterComponent();

			HoverPointLightComponent->SetLightColor( FLinearColor::Red );
			//Hand.HoverPointLightComponent->SetLightColor( FLinearColor( 0.0f, 1.0f, 0.2f, 1.0f ) );
			HoverPointLightComponent->SetIntensity( 30.0f );	// @todo: VREditor tweak
			HoverPointLightComponent->SetMobility( EComponentMobility::Movable );
			HoverPointLightComponent->SetAttenuationRadius( VREd::LaserPointerLightRadius->GetFloat() );
			HoverPointLightComponent->bUseInverseSquaredFalloff = false;
			HoverPointLightComponent->SetCastShadows( false );
		}
	}

	{
		const int32 NumLaserSplinePoints = 12;

		UStaticMesh* MiddleSplineMesh = AssetContainer.LaserPointerMesh;
		check (MiddleSplineMesh != nullptr);
		UStaticMesh* StartSplineMesh = AssetContainer.LaserPointerStartMesh;
		check (StartSplineMesh != nullptr);
		UStaticMesh* EndSplineMesh = AssetContainer.LaserPointerEndMesh;
		check (EndSplineMesh != nullptr);

		LaserSplineComponent = NewObject<USplineComponent>(OwningActor);
		OwningActor->AddOwnedComponent(LaserSplineComponent);
		LaserSplineComponent->SetupAttachment(MotionControllerComponent);
		LaserSplineComponent->RegisterComponent();
		LaserSplineComponent->SetVisibility(false);

		for (int32 i = 0; i < NumLaserSplinePoints; i++)
		{
			USplineMeshComponent* SplineSegment = NewObject<USplineMeshComponent>(OwningActor);
			OwningActor->AddOwnedComponent(SplineSegment);
			SplineSegment->SetMobility(EComponentMobility::Movable);
			SplineSegment->SetCollisionEnabled(ECollisionEnabled::NoCollision);
			SplineSegment->PostPhysicsComponentTick.bCanEverTick = false;
			SplineSegment->SetupAttachment(MotionControllerComponent);

			UStaticMesh* StaticMesh = nullptr;
			if (i == 0)
			{
				StaticMesh = StartSplineMesh;
			}
			else if (i == NumLaserSplinePoints)
			{
				StaticMesh = EndSplineMesh;
			}
			else
			{
				StaticMesh = MiddleSplineMesh;
			}
			
			SplineSegment->SetStaticMesh(StaticMesh);
			SplineSegment->bTickInEditor = true;
			SplineSegment->bCastDynamicShadow = false;
			SplineSegment->CastShadow = false;
			SplineSegment->SetMaterial(0, LaserPointerMID);
			SplineSegment->SetMaterial(1, TranslucentLaserPointerMID);
			SplineSegment->SetVisibility(true);
			SplineSegment->RegisterComponent();

			LaserSplineMeshComponents.Add(SplineSegment);
		}
	}
}


void UVREditorMotionControllerInteractor::SetControllerHandSide( const EControllerHand InControllerHandSide )
{
	ControllerHandSide = InControllerHandSide;
}


void UVREditorMotionControllerInteractor::Shutdown()
{
	Super::Shutdown();

	MotionControllerComponent = nullptr;
	HandMeshComponent = nullptr;
	LaserPointerMID = nullptr;
	TranslucentLaserPointerMID = nullptr;
	HoverMeshComponent = nullptr;
	HoverPointLightComponent = nullptr;
	HandMeshComponent = nullptr;
}

void UVREditorMotionControllerInteractor::Tick( const float DeltaTime )
{
	Super::Tick( DeltaTime );
	
	{
		const float WorldScaleFactor = WorldInteraction->GetWorldScaleFactor();

		// @todo vreditor: Manually ticking motion controller components
		MotionControllerComponent->TickComponent( DeltaTime, ELevelTick::LEVELTICK_PauseTick, nullptr );

		// The hands need to stay the same size relative to our tracking space, so we inverse compensate for world to meters scale here
		// NOTE: We don't need to set the hand mesh location and rotation, as the MotionControllerComponent does that itself
		if ( ControllerHandSide == EControllerHand::Right &&
			GetHMDDeviceType() == EHMDDeviceType::DT_OculusRift )	// Oculus has asymmetrical controllers, so we mirror the mesh horizontally
		{
			HandMeshComponent->SetRelativeScale3D( FVector( WorldScaleFactor, -WorldScaleFactor, WorldScaleFactor ) );
		}
		else
		{
			HandMeshComponent->SetRelativeScale3D( FVector( WorldScaleFactor ) );
		}
	}

	UpdateRadialMenuInput(DeltaTime);

	{
		const float WorldScaleFactor = WorldInteraction->GetWorldScaleFactor();

		// Don't bother drawing hands if we're not currently tracking them.
		if ( bHaveMotionController )
		{
			HandMeshComponent->SetVisibility( true );
		}
		else
		{
			HandMeshComponent->SetVisibility( false );
		}

		// Offset the beginning of the laser pointer a bit, so that it doesn't overlap the hand mesh
		const float LaserPointerStartOffset =
			WorldScaleFactor *
			( GetVRMode().GetHMDDeviceType() == EHMDDeviceType::DT_OculusRift ? VREd::OculusLaserPointerStartOffset->GetFloat() : VREd::ViveLaserPointerStartOffset->GetFloat() );

		// The laser pointer needs to stay the same size relative to our tracking space, so we inverse compensate for world to meters scale here
		float LaserPointerRadius = VREd::LaserPointerRadius->GetFloat() * WorldScaleFactor;
		float HoverMeshRadius = VREd::LaserPointerHoverBallRadius->GetFloat() * WorldScaleFactor;

		// If we're hovering over something really close to the camera, go ahead and shrink the effect
		// @todo vreditor: Can we make this actually just sized based on distance automatically?  The beam and impact point are basically a cone.
		if( IsHoveringOverUI() )
		{
			LaserPointerRadius *= VREd::LaserRadiusScaleWhenOverUI->GetFloat();
			HoverMeshRadius *= VREd::HoverBallRadiusScaleWhenOverUI->GetFloat();
		}

		const bool bEvenIfBlocked = false;

		// If we're currently grabbing the world with this interactor
		const bool bDraggingWorld = (InteractorData.DraggingMode == EViewportInteractionDraggingMode::World || 
			(GetOtherInteractor() != nullptr && GetOtherInteractor()->GetInteractorData().DraggingMode == EViewportInteractionDraggingMode::World && InteractorData.DraggingMode == EViewportInteractionDraggingMode::AssistingDrag));

		FVector LaserPointerStart, LaserPointerEnd;
		const bool bHasLaser = GetLaserPointer(/* Out */ LaserPointerStart, /* Out */ LaserPointerEnd, bEvenIfBlocked);
		if (bForceShowLaser || (bHasLaser && !bDraggingWorld))
		{
			// Only show the laser if we're actually in VR
			SetLaserVisibility(GetVRMode().IsActuallyUsingVR());

			// NOTE: We don't need to set the laser pointer location and rotation, as the MotionControllerComponent will do
			// that later in the frame.  

			// If we're actively dragging something around, then we'll crop the laser length to the hover impact
			// point.  Otherwise, we always want the laser to protrude through hovered objects, so that you can
			// interact with translucent gizmo handles that are occluded by geometry
			if( IsHoveringOverGizmo() ||
				IsHoveringOverUI() || 
				IsHovering() )
			{
				LaserPointerEnd = GetHoverLocation();
			}

			if( IsHovering() && !GetIsLaserBlocked() )
			{
				const FVector DirectionTowardHoverLocation = (GetHoverLocation() - LaserPointerStart).GetSafeNormal();

				// The hover effect needs to stay the same size relative to our tracking space, so we inverse compensate for world to meters scale here
				HoverMeshComponent->SetRelativeScale3D( FVector( HoverMeshRadius * 2.0f ) * ( 0.25f + 1.0f - this->GetSelectAndMoveTriggerValue() * 0.75f ) );
				HoverMeshComponent->SetVisibility( true );
				HoverMeshComponent->SetWorldLocation( GetHoverLocation() );

				// Show the light too, unless it's on top of UI.  It looks too distracting on top of UI.
				HoverPointLightComponent->SetVisibility( !IsHoveringOverUI() );

				// Update radius for world scaling
				HoverPointLightComponent->SetAttenuationRadius( VREd::LaserPointerLightRadius->GetFloat() * WorldScaleFactor );

				// Pull hover light back a bit from the end of the ray
				const float PullBackAmount = VREd::LaserPointerLightPullBackDistance->GetFloat() * WorldInteraction->GetWorldScaleFactor();
				HoverPointLightComponent->SetWorldLocation( GetHoverLocation() - PullBackAmount * DirectionTowardHoverLocation );
			}
			else
			{
				HoverMeshComponent->SetVisibility( false );
				HoverPointLightComponent->SetVisibility( false );
			}
		}
		else
		{
			SetLaserVisibility(false);
			HoverMeshComponent->SetVisibility( false );
			HoverPointLightComponent->SetVisibility( false );
		}

		// Update the curved laser. No matter if we actually show the laser it needs to update, 
		// so if in the next frame it needs to be visible it won't interpolate from a previous location.
		{
			// Get the hand transform and forward vector.
			FTransform InteractorTransform;
			FVector InteractorForwardVector;
			GetTransformAndForwardVector( /* Out */ InteractorTransform, /* Out */ InteractorForwardVector);

			// Offset the start point of the laser.
			LaserPointerStart = InteractorTransform.GetLocation() + (InteractorForwardVector * FVector(LaserPointerStartOffset, 0.0f, 0.0f));

			UpdateSplineLaser(LaserPointerStart, LaserPointerEnd, InteractorForwardVector);
		}

		bForceShowLaser = false;
	}

	// Updating laser colors for both hands
	{
		FLinearColor ResultColor;
		float CrawlSpeed = 0.0f;
		float CrawlFade = 0.0f;

		if (ForceLaserColor.IsSet())
		{
			ResultColor = ForceLaserColor.GetValue();
			ForceLaserColor.Reset();
		}
		else
		{
			if (InteractorData.HoveringOverTransformGizmoComponent != nullptr)
			{
				ResultColor = WorldInteraction->GetColor(UViewportWorldInteraction::EColors::GizmoHover);
			}
			else
			{
				const EViewportInteractionDraggingMode DraggingMode = GetDraggingMode();
				if (DraggingMode == EViewportInteractionDraggingMode::World || 
					(DraggingMode == EViewportInteractionDraggingMode::AssistingDrag && GetOtherInteractor() != nullptr && GetOtherInteractor()->GetDraggingMode() == EViewportInteractionDraggingMode::World))
				{
					// We can teleport in this mode, so animate the laser a bit
					CrawlFade = 1.0f;
					CrawlSpeed = 5.0f;
					ResultColor = GetVRMode().GetColor(UVREditorMode::EColors::WorldDraggingColor);
				}
				else if (DraggingMode == EViewportInteractionDraggingMode::TransformablesAtLaserImpact ||
						 DraggingMode == EViewportInteractionDraggingMode::Material ||
						 DraggingMode == EViewportInteractionDraggingMode::TransformablesFreely ||
						 DraggingMode == EViewportInteractionDraggingMode::AssistingDrag)
				{
					ResultColor = GetVRMode().GetColor(UVREditorMode::EColors::SelectionColor);
				}
				else if (DraggingMode == EViewportInteractionDraggingMode::TransformablesWithGizmo)
				{
					ResultColor = WorldInteraction->GetColor(UViewportWorldInteraction::EColors::GizmoHover);
				}
				else if (DraggingMode == EViewportInteractionDraggingMode::Interactable ||
						(GetVRMode().GetUISystem().IsInteractorDraggingDockUI(this) && GetVRMode().GetUISystem().IsDraggingDockUI()))
				{
					ResultColor = GetVRMode().GetColor(UVREditorMode::EColors::UIColor);
				}
				else if (GetLastHoverComponent() != nullptr && GetLastHoverComponent()->GetOwner() != nullptr && GetLastHoverComponent()->GetOwner()->IsA(AVREditorDockableWindow::StaticClass()))
				{
					AVREditorDockableWindow* HoveredDockWindow = Cast<AVREditorDockableWindow>(GetLastHoverComponent()->GetOwner());
					if (HoveredDockWindow && HoveredDockWindow->GetSelectionBarMeshComponent() == GetLastHoverComponent())
					{
						ResultColor = GetVRMode().GetColor(UVREditorMode::EColors::UIColor);
					}
					else
					{
						ResultColor = GetVRMode().GetColor(UVREditorMode::EColors::DefaultColor);
					}
				}
				else if (ControllerType == EControllerType::UI)
				{
					ResultColor = GetVRMode().GetColor(UVREditorMode::EColors::UIColor);
				}
				else if (IsHoveringOverSelectedActor())
				{
					ResultColor = GetVRMode().GetColor(UVREditorMode::EColors::SelectionColor);
				}
				else
				{
					ResultColor = GetVRMode().GetColor(UVREditorMode::EColors::DefaultColor);
				}
			}
		}

		SetLaserVisuals(ResultColor, CrawlFade, CrawlSpeed);
	}

	UpdateHelpLabels();
}

void UVREditorMotionControllerInteractor::CalculateDragRay( float& InOutDragRayLength, float& InOutDragRayVelocity)
{
	const FTimespan CurrentTime = FTimespan::FromSeconds( FPlatformTime::Seconds() );
	const float WorldScaleFactor = WorldInteraction->GetWorldScaleFactor();

	// If we're dragging an object, go ahead and slide the object along the ray based on how far they slide their touch
	// Make sure they are touching the trackpad, otherwise we get bad data
	if ( bIsTrackpadPositionValid[ 1 ] )
	{
		const bool bIsAbsolute = ( GetVRMode().GetHMDDeviceType() == EHMDDeviceType::DT_SteamVR );
		float SlideDelta = GetTrackpadSlideDelta() * WorldScaleFactor;

		if ( !FMath::IsNearlyZero( SlideDelta ) )
		{
			InOutDragRayLength += SlideDelta;

			InOutDragRayVelocity = 0.0f;

			// Don't apply inertia unless the user dragged a decent amount this frame
			if ( bIsAbsolute && FMath::Abs( SlideDelta ) >= VREd::MinVelocityForInertia->GetFloat() * WorldScaleFactor )
			{
				// Don't apply inertia if our data is sort of old
				if ( CurrentTime - LastTrackpadPositionUpdateTime <= FTimespan::FromSeconds( 1.0f / 30.0f ) )
				{
					InOutDragRayVelocity = SlideDelta;
				}
			}

			// Don't go too far
			if ( InOutDragRayLength < 0.0f )
			{
				InOutDragRayLength = 0.0f;
				InOutDragRayVelocity = 0.0f;
			}
		}
	}
	else
	{
		if ( !FMath::IsNearlyZero( InOutDragRayVelocity ) )
		{
			// Apply drag ray length inertia
			InOutDragRayLength += InOutDragRayVelocity;

			// Don't go too far!
			if ( InOutDragRayLength < 0.0f )
			{
				InOutDragRayLength = 0.0f;
				InOutDragRayVelocity = 0.0f;
			}

			// Apply damping
			FVector RayVelocityVector( InOutDragRayVelocity, 0.0f, 0.0f );
			const bool bVelocitySensitive = true;
			WorldInteraction->ApplyVelocityDamping( RayVelocityVector, bVelocitySensitive );
			InOutDragRayVelocity = RayVelocityVector.X;
		}
		else
		{
			InOutDragRayVelocity = 0.0f;
		}
	}
}


EHMDDeviceType::Type UVREditorMotionControllerInteractor::GetHMDDeviceType() const
{
	return GEngine->HMDDevice.IsValid() ? GEngine->HMDDevice->GetHMDDeviceType() : EHMDDeviceType::DT_SteamVR; //@todo: ViewportInteraction, assumption that it's steamvr ??
}


void UVREditorMotionControllerInteractor::PreviewInputKey( FEditorViewportClient& ViewportClient, FViewportActionKeyInput& Action, const FKey Key, const EInputEvent Event, bool& bOutWasHandled )
{
	if (bIsScrubbingSequence && 
		GetControllerType() == EControllerType::UI && 
		Action.ActionType == ViewportWorldActionTypes::SelectAndMove &&
		Action.Event == IE_Pressed)
	{
		ToggleSequencerScrubbingMode();
		GetVRMode().GetUISystem().TryToSpawnRadialMenu(this, true);
	}

	// Update touch state
	if( Action.ActionType == VRActionTypes::Touch )
	{
		if( Event == IE_Pressed )
		{
			bIsTouchingTrackpad = true;

			// Set initial position when starting to touch the trackpad
			InitialTouchPosition = TrackpadPosition;
		}
		else if( Event == IE_Released )
		{
			bIsTouchingTrackpad = false;
			bIsTrackpadPositionValid[ 0 ] = false;
			bIsTrackpadPositionValid[ 1 ] = false;

			// Detect swipe on trackpad.
			const FVector2D SwipeDelta = LastTrackpadPosition - InitialTouchPosition;
			const float AbsSwipeDeltaX = FMath::Abs(SwipeDelta.X);
			const float AbsSwipeDeltaY = FMath::Abs(SwipeDelta.Y);
			if (!FMath::IsNearlyZero(SwipeDelta.X, 1.0f) && AbsSwipeDeltaX > AbsSwipeDeltaY)
			{
				if (SwipeDelta.X > 0)
				{
					LastSwipe = ETouchSwipeDirection::Right;
					UndoRedoFromSwipe(LastSwipe);
				}
				else if (SwipeDelta.X < 0)
				{
					LastSwipe = ETouchSwipeDirection::Left;
					UndoRedoFromSwipe(LastSwipe);
				}
			}
			else if (!FMath::IsNearlyZero(SwipeDelta.Y, 1.0f))
			{
				if (SwipeDelta.Y > 0)
				{
					LastSwipe = ETouchSwipeDirection::Up;
				}
				else if (SwipeDelta.Y < 0)
				{
					LastSwipe = ETouchSwipeDirection::Down;
				}
			}
		}
	}

	if( Action.ActionType == VRActionTypes::ConfirmRadialSelection )
	{
		bIsPressingTrackpad = Event == IE_Released ? false : true;
	}

	if( GetControllerType() == EControllerType::Laser )
	{
		// Are we holding "up" on the trackpad?
		const bool bIsHoldingUpOnTrackpad =
			bIsTrackpadPositionValid[0] && bIsTrackpadPositionValid[1] &&
			TrackpadPosition.Y >= VREd::MinTrackpadOffsetBeforeRadialMenu->GetFloat() &&
			( GetHMDDeviceType() == EHMDDeviceType::DT_OculusRift || bIsPressingTrackpad );

		if( bIsHoldingUpOnTrackpad && Action.ActionType == ViewportWorldActionTypes::SelectAndMove && Event == IE_Pressed )
		{
			bOutWasHandled = true;

			// Try to place the object currently selected
			TArray<UObject*> ObjectsToPlace;
			{
				FEditorDelegates::LoadSelectedAssetsIfNeeded.Broadcast();
				GEditor->GetSelectedObjects()->GetSelectedObjects( /* Out */ ObjectsToPlace );
			}

			if( ObjectsToPlace.Num() > 0 )
			{
				Action.bIsInputCaptured = true;

				const bool bShouldInterpolateFromDragLocation = false;
				UActorFactory* FactoryToUse = nullptr;	// Use default factory
				GetVRMode().GetPlacementSystem()->StartPlacingObjects( ObjectsToPlace, FactoryToUse, this, bShouldInterpolateFromDragLocation );
			}
		}
	}


	Super::PreviewInputKey( ViewportClient, Action, Key, Event, bOutWasHandled );
}


void UVREditorMotionControllerInteractor::HandleInputKey( FEditorViewportClient& ViewportClient, FViewportActionKeyInput& Action, const FKey Key, const EInputEvent Event, bool& bOutWasHandled )
{
	if( !bOutWasHandled && Action.ActionType == VRActionTypes::ConfirmRadialSelection )
	{
		bOutWasHandled = true;
		const EViewportInteractionDraggingMode DraggingMode = GetDraggingMode();

		if( Event == IE_Pressed )
		{ 
			// Start dragging at laser impact when already dragging actors freely
			if( DraggingMode == EViewportInteractionDraggingMode::TransformablesFreely )
			{
				FVector PlaceAt = GetHoverLocation();
				const bool bIsPlacingActors = true;
				const bool bAllowInterpolationWhenPlacing = true;
				const bool bStartTransaction = true;
				const bool bWithGrabberSphere = false;	// Never use the grabber sphere when dragging at laser impact
				WorldInteraction->StartDragging( this, WorldInteraction->GetTransformGizmoActor()->GetRootComponent(), PlaceAt, bIsPlacingActors, bAllowInterpolationWhenPlacing, bStartTransaction, bWithGrabberSphere );
			}
		}
		else if( Event == IE_Released )
		{
			// Disable dragging at laser impact when releasing
			if( DraggingMode == EViewportInteractionDraggingMode::TransformablesAtLaserImpact )
			{
				SetDraggingMode( EViewportInteractionDraggingMode::TransformablesFreely );
			}
		}
	}

	ApplyButtonPressColors( Action );
}

void UVREditorMotionControllerInteractor::HandleInputAxis( FEditorViewportClient& ViewportClient, FViewportActionKeyInput& Action, const FKey Key, const float Delta, const float DeltaTime, bool& bOutWasHandled )
{
	if ( Action.ActionType == TriggerAxis )
	{
		const float TriggerPressedThreshold = ( GetHMDDeviceType() == EHMDDeviceType::DT_OculusRift ) ? GetDefault<UVRModeSettings>()->TriggerPressedThreshold_Rift : GetDefault<UVRModeSettings>()->TriggerPressedThreshold_Vive;
		const float TriggerDeadZone = ( GetHMDDeviceType() == EHMDDeviceType::DT_OculusRift ) ? VREd::TriggerDeadZone_Rift->GetFloat() : VREd::TriggerDeadZone_Vive->GetFloat();

		// Synthesize "lightly pressed" events for the trigger
		{
			// Store latest trigger value amount
			SelectAndMoveTriggerValue = Delta;

			if( !bIsTriggerPressed &&			// Don't fire if we are already pressed
				bHasTriggerBeenReleasedSinceLastPress &&	// Only if we've been fully released since the last time we fired
				Delta >= TriggerPressedThreshold )
			{
				bIsTriggerPressed = true;
				bHasTriggerBeenReleasedSinceLastPress = false;

				// Synthesize an input key for this light press
				const EInputEvent InputEvent = IE_Pressed;
				const bool bWasLightPressHandled = UViewportInteractor::HandleInputKey( ViewportClient, ControllerHandSide == EControllerHand::Left ? MotionController_Left_PressedTriggerAxis : MotionController_Right_PressedTriggerAxis, InputEvent );
			}
			else if ( bIsTriggerPressed && Delta < TriggerPressedThreshold )
			{
				bIsTriggerPressed = false;

				// Synthesize an input key for this light press
				const EInputEvent InputEvent = IE_Released;
				const bool bWasLightReleaseHandled = UViewportInteractor::HandleInputKey( ViewportClient, ControllerHandSide == EControllerHand::Left ? MotionController_Left_PressedTriggerAxis : MotionController_Right_PressedTriggerAxis, InputEvent );
			}
		}

		if ( !bHasTriggerBeenReleasedSinceLastPress && Delta < TriggerDeadZone )
		{
			bHasTriggerBeenReleasedSinceLastPress = true;
		}

		// Synthesize "fully pressed" events for the trigger
		{
			const float TriggerFullyPressedThreshold = (GetHMDDeviceType() == EHMDDeviceType::DT_OculusRift) ? VREd::TriggerFullyPressedThreshold_Rift->GetFloat() : VREd::TriggerFullyPressedThreshold_Vive->GetFloat();

			if ( !bIsTriggerFullyPressed &&	// Don't fire if we are already pressed
				 Delta >= TriggerFullyPressedThreshold )
			{
				bIsTriggerFullyPressed = true;

				const EInputEvent InputEvent = IE_Pressed;
				UViewportInteractor::HandleInputKey( ViewportClient, ControllerHandSide == EControllerHand::Left ? MotionController_Left_FullyPressedTriggerAxis : MotionController_Right_FullyPressedTriggerAxis, InputEvent );
			}
			else if ( bIsTriggerFullyPressed && Delta < TriggerPressedThreshold )
			{
				bIsTriggerFullyPressed = false;

				const EInputEvent InputEvent = IE_Released;
				UViewportInteractor::HandleInputKey( ViewportClient, ControllerHandSide == EControllerHand::Left ? MotionController_Left_FullyPressedTriggerAxis : MotionController_Right_FullyPressedTriggerAxis, InputEvent );
			}
		}
	}

	if ( !bOutWasHandled )
	{
		if ( Action.ActionType == VRActionTypes::TrackpadPositionX )
		{
			LastTrackpadPosition.X = bIsTrackpadPositionValid[ 0 ] ? TrackpadPosition.X : Delta;
			LastTrackpadPositionUpdateTime = FTimespan::FromSeconds( FPlatformTime::Seconds() );
			TrackpadPosition.X = Delta;
			bIsTrackpadPositionValid[ 0 ] = true;
		}

		if ( Action.ActionType == VRActionTypes::TrackpadPositionY )
		{
			float DeltaAxis = Delta;
			if ( VREd::InvertTrackpadVertical->GetInt() != 0 )
			{
				DeltaAxis = -DeltaAxis;	// Y axis is inverted from HMD
			}

			LastTrackpadPosition.Y = bIsTrackpadPositionValid[ 1 ] ? TrackpadPosition.Y : DeltaAxis;
			LastTrackpadPositionUpdateTime = FTimespan::FromSeconds( FPlatformTime::Seconds() );
			TrackpadPosition.Y = DeltaAxis;
			bIsTrackpadPositionValid[ 1 ] = true;
		}
	}

	Super::HandleInputAxis( ViewportClient, Action, Key, Delta, DeltaTime, bOutWasHandled );
}

void UVREditorMotionControllerInteractor::PollInput()
{
	bHaveMotionController = false;
	InteractorData.LastTransform = InteractorData.Transform;
	InteractorData.LastRoomSpaceTransform = InteractorData.RoomSpaceTransform;

	// Generic motion controllers
	TArray<IMotionController*> MotionControllers = IModularFeatures::Get().GetModularFeatureImplementations<IMotionController>( IMotionController::GetModularFeatureName() );
	for ( auto MotionController : MotionControllers )	// @todo viewportinteraction: Needs support for multiple pairs of motion controllers
	{
		if ( MotionController != nullptr && !bHaveMotionController )
		{
			FVector Location = FVector::ZeroVector;
			FRotator Rotation = FRotator::ZeroRotator; 
			if ( MotionController->GetControllerOrientationAndPosition( WorldInteraction->GetMotionControllerID(), ControllerHandSide, /* Out */ Rotation, /* Out */ Location, GetVRMode().GetWorldScaleFactor() ) )
			{
				bHaveMotionController = true;
				InteractorData.RoomSpaceTransform = FTransform( Rotation.Quaternion(), Location, FVector( 1.0f ) );
				InteractorData.Transform = InteractorData.RoomSpaceTransform * WorldInteraction->GetRoomTransform();
			}
		}
	}
}

void UVREditorMotionControllerInteractor::PlayHapticEffect( const float Strength )
{
	IInputInterface* InputInterface = FSlateApplication::Get().GetInputInterface();
	if ( InputInterface )
	{
		const double CurrentTime = FPlatformTime::Seconds();

		//@todo viewportinteration
		FForceFeedbackValues ForceFeedbackValues;
		ForceFeedbackValues.LeftLarge = ControllerHandSide == EControllerHand::Left ? Strength : 0;
		ForceFeedbackValues.RightLarge = ControllerHandSide == EControllerHand::Right ? Strength : 0;

		// @todo vreditor: If an Xbox controller is plugged in, this causes both the motion controllers and the Xbox controller to vibrate!
		InputInterface->SetForceFeedbackChannelValues( WorldInteraction->GetMotionControllerID(), ForceFeedbackValues );
	}
}

bool UVREditorMotionControllerInteractor::GetTransformAndForwardVector( FTransform& OutHandTransform, FVector& OutForwardVector ) const
{
	if ( bHaveMotionController )
	{
		OutHandTransform = InteractorData.Transform;

		const float LaserPointerRotationOffset = GetHMDDeviceType() == EHMDDeviceType::DT_OculusRift ? VREd::OculusLaserPointerRotationOffset->GetFloat() : VREd::ViveLaserPointerRotationOffset->GetFloat();
		OutForwardVector = OutHandTransform.GetRotation().RotateVector( FRotator( LaserPointerRotationOffset, 0.0f, 0.0f ).RotateVector( FVector( 1.0f, 0.0f, 0.0f ) ) );

		return true;
	}

	return false;
}

float UVREditorMotionControllerInteractor::GetTrackpadSlideDelta( const bool Axis )
{
	const bool bIsAbsolute = ( GetVRMode().GetHMDDeviceType() == EHMDDeviceType::DT_SteamVR );
	float SlideDelta = 0.0f;
	if ( bIsTouchingTrackpad || !bIsAbsolute )
	{
		if ( bIsAbsolute )
		{
			SlideDelta = ( ( TrackpadPosition[Axis] - LastTrackpadPosition[Axis] ) * VREd::TrackpadAbsoluteDragSpeed->GetFloat() );
		}
		else
		{
			SlideDelta = ( TrackpadPosition[Axis] * VREd::TrackpadRelativeDragSpeed->GetFloat() );
		}
	}

	return SlideDelta;
}

EControllerHand UVREditorMotionControllerInteractor::GetControllerSide() const
{
	return ControllerHandSide;
}

UMotionControllerComponent* UVREditorMotionControllerInteractor::GetMotionControllerComponent() const
{
	return MotionControllerComponent;
}

void UVREditorMotionControllerInteractor::ResetTrackpad()
{
	TrackpadPosition = FVector2D::ZeroVector;
	bIsTouchingTrackpad = false;
	bIsTrackpadPositionValid[0] = false;
	bIsTrackpadPositionValid[1] = false;
}

bool UVREditorMotionControllerInteractor::IsTouchingTrackpad() const
{
	return bIsTouchingTrackpad;
}

FVector2D UVREditorMotionControllerInteractor::GetTrackpadPosition() const
{
	return TrackpadPosition;
}

FVector2D UVREditorMotionControllerInteractor::GetLastTrackpadPosition() const
{
	return LastTrackpadPosition;
}

bool UVREditorMotionControllerInteractor::IsTrackpadPositionValid( const int32 AxisIndex ) const
{
	return bIsTrackpadPositionValid[ AxisIndex ];
}

FTimespan& UVREditorMotionControllerInteractor::GetLastTrackpadPositionUpdateTime()
{
	return LastTrackpadPositionUpdateTime;
}

FTimespan& UVREditorMotionControllerInteractor::GetLastActiveTrackpadUpdateTime()
{
	return LastActiveTrackpadUpdateTime;
}

void UVREditorMotionControllerInteractor::SetForceShowLaser(const bool bInForceShow)
{
	bForceShowLaser = bInForceShow;
}

void UVREditorMotionControllerInteractor::SetForceLaserColor(const FLinearColor& InColor)
{
	ForceLaserColor = InColor;
}

/** Changes the color of the buttons on the handmesh */
void UVREditorMotionControllerInteractor::ApplyButtonPressColors( const FViewportActionKeyInput& Action )
{
	const float PressStrength = 10.0f;
	const FName ActionType = Action.ActionType;
	const EInputEvent Event = Action.Event;

	// Trigger
	if ( ActionType == ViewportWorldActionTypes::SelectAndMove )
	{
		static FName StaticTriggerParameter( "B1" );
		SetMotionControllerButtonPressedVisuals( Event, StaticTriggerParameter, PressStrength );
	}

	// Shoulder button
	if ( ActionType == ViewportWorldActionTypes::WorldMovement )
	{
		static FName StaticShoulderParameter( "B2" );
		SetMotionControllerButtonPressedVisuals( Event, StaticShoulderParameter, PressStrength );
	}

	// Trackpad
	if ( ActionType == VRActionTypes::ConfirmRadialSelection )
	{
		static FName StaticTrackpadParameter( "B3" );
		SetMotionControllerButtonPressedVisuals( Event, StaticTrackpadParameter, PressStrength );
	}

	// Modifier
	if( ActionType == VRActionTypes::Modifier )
	{
		static FName StaticModifierParameter( "B4" );
		SetMotionControllerButtonPressedVisuals( Event, StaticModifierParameter, PressStrength );
	}

	if( GetVRMode().GetHMDDeviceType() == EHMDDeviceType::DT_OculusRift && ActionType == VRActionTypes::Modifier2 )
	{
		static FName StaticModifierParameter( "B5" );
		SetMotionControllerButtonPressedVisuals( Event, StaticModifierParameter, PressStrength );
	}
}

void UVREditorMotionControllerInteractor::SetMotionControllerButtonPressedVisuals( const EInputEvent Event, const FName& ParameterName, const float PressStrength )
{
	if ( Event == IE_Pressed )
	{
		HandMeshMID->SetScalarParameterValue( ParameterName, PressStrength );
	}
	else if ( Event == IE_Released )
	{
		HandMeshMID->SetScalarParameterValue( ParameterName, 0.0f );
	}
}

void UVREditorMotionControllerInteractor::ShowHelpForHand( const bool bShowIt )
{
	if ( bShowIt != bWantHelpLabels )
	{
		bWantHelpLabels = bShowIt;

		const FTimespan CurrentTime = FTimespan::FromSeconds( FApp::GetCurrentTime() );
		const FTimespan TimeSinceStartedFadingOut = CurrentTime - HelpLabelShowOrHideStartTime;
		const FTimespan HelpLabelFadeDuration = FTimespan::FromSeconds( VREd::HelpLabelFadeDuration->GetFloat() );

		// If we were already fading, account for that here
		if ( TimeSinceStartedFadingOut < HelpLabelFadeDuration )
		{
			// We were already fading, so we'll reverse the time value so it feels continuous
			HelpLabelShowOrHideStartTime = CurrentTime - ( HelpLabelFadeDuration - TimeSinceStartedFadingOut );
		}
		else
		{
			HelpLabelShowOrHideStartTime = FTimespan::FromSeconds( FApp::GetCurrentTime() );
		}

		if ( bShowIt && HelpLabels.Num() == 0 )
		{
			for ( const auto& KeyToAction : KeyToActionMap )
			{
				const FKey Key = KeyToAction.Key;
				const FViewportActionKeyInput& Action = KeyToAction.Value;

				UStaticMeshSocket* Socket = FindMeshSocketForKey( HandMeshComponent->GetStaticMesh(), Key );
				if ( Socket != nullptr )
				{
					FText LabelText;
					FString ComponentName;

					if ( Action.ActionType == VRActionTypes::Modifier )
					{
						LabelText = LOCTEXT( "ModifierHelp", "Modifier" );
						ComponentName = TEXT( "ModifierHelp" );
					}
					else if ( Action.ActionType == ViewportWorldActionTypes::WorldMovement )
					{
						LabelText = LOCTEXT( "WorldMovementHelp", "Move World" );
						ComponentName = TEXT( "WorldMovementHelp" );
					}
					else if ( Action.ActionType == ViewportWorldActionTypes::SelectAndMove_FullyPressed )
					{
						LabelText = LOCTEXT( "SelectAndMove_FullyPressedHelp", "Select & Move" );
						ComponentName = TEXT( "SelectAndMove_FullyPressedHelp" );
					}
					else if ( Action.ActionType == ViewportWorldActionTypes::SelectAndMove )
					{
						LabelText = LOCTEXT( "SelectAndMove_Help", "Select & Move" );
						ComponentName = TEXT( "SelectAndMove_Help" );
					}
					else if ( Action.ActionType == VRActionTypes::Touch )
					{
						LabelText = LOCTEXT( "TouchHelp", "Slide" );
						ComponentName = TEXT( "TouchHelp" );
					}
					else if ( Action.ActionType == ViewportWorldActionTypes::Undo )
					{
						LabelText = LOCTEXT( "UndoHelp", "Undo" );
						ComponentName = TEXT( "UndoHelp" );
					}
					else if ( Action.ActionType == ViewportWorldActionTypes::Redo )
					{
						LabelText = LOCTEXT( "RedoHelp", "Redo" );
						ComponentName = TEXT( "RedoHelp" );
					}
					else if ( Action.ActionType == ViewportWorldActionTypes::Delete )
					{
						LabelText = LOCTEXT( "DeleteHelp", "Delete" );
						ComponentName = TEXT( "DeleteHelp" );
					}
					else if ( Action.ActionType == VRActionTypes::ConfirmRadialSelection )
					{
						LabelText = LOCTEXT( "ConfirmRadialSelectionHelp", "Radial Menu" );
						ComponentName = TEXT( "ConfirmRadialSelectionHelp" );
					}
					
					const bool bWithSceneComponent = false;	// Nope, we'll spawn our own inside AFloatingText
					check( VRMode );
					AFloatingText* FloatingText = GetVRMode().SpawnTransientSceneActor<AFloatingText>(ComponentName);
					FloatingText->SetText( LabelText );

					HelpLabels.Add( Key, FloatingText );
				}
			}
		}
	}
}


void UVREditorMotionControllerInteractor::UpdateHelpLabels()
{
	const FTimespan HelpLabelFadeDuration = FTimespan::FromSeconds( VREd::HelpLabelFadeDuration->GetFloat() );

	const FTransform HeadTransform = GetVRMode().GetHeadTransform();

	// Only show help labels if the hand is pretty close to the face
	const float DistanceToHead = ( GetTransform().GetLocation() - HeadTransform.GetLocation() ).Size();
	const float MinDistanceToHeadForHelp = VREd::HelpLabelFadeDistance->GetFloat() * GetVRMode().GetWorldScaleFactor();	// (in cm)
	bool bShowHelp = VREd::ShowControllerHelpLabels->GetInt() != 0 && DistanceToHead <= MinDistanceToHeadForHelp;

	// Don't show help if a UI is summoned on that hand
	if ( HasUIOnForearm() || GetVRMode().GetUISystem().IsShowingRadialMenu( this ) )
	{
		bShowHelp = false;
	}

	ShowHelpForHand( bShowHelp );

	// Have the labels finished fading out?  If so, we'll kill their actors!
	const FTimespan CurrentTime = FTimespan::FromSeconds( FApp::GetCurrentTime() );
	const FTimespan TimeSinceStartedFadingOut = CurrentTime - HelpLabelShowOrHideStartTime;
	if ( !bWantHelpLabels && ( TimeSinceStartedFadingOut > HelpLabelFadeDuration ) )
	{
		// Get rid of help text
		for ( auto& KeyAndValue : HelpLabels )
		{
			AFloatingText* FloatingText = KeyAndValue.Value;
			GetVRMode().DestroyTransientActor(FloatingText);
		}
		HelpLabels.Reset();
	}
	else
	{
		// Update fading state
		float FadeAlpha = FMath::Clamp( ( float ) TimeSinceStartedFadingOut.GetTotalSeconds() / ( float ) HelpLabelFadeDuration.GetTotalSeconds(), 0.0f, 1.0f );
		if ( !bWantHelpLabels )
		{
			FadeAlpha = 1.0f - FadeAlpha;
		}

		// Exponential falloff, so the fade is really obvious (gamma/HDR)
		FadeAlpha = FMath::Pow( FadeAlpha, 3.0f );

		for ( auto& KeyAndValue : HelpLabels )
		{
			const FKey Key = KeyAndValue.Key;
			AFloatingText* FloatingText = KeyAndValue.Value;

			UStaticMeshSocket* Socket = FindMeshSocketForKey( HandMeshComponent->GetStaticMesh(), Key );
			check( Socket != nullptr );
			FTransform SocketRelativeTransform( Socket->RelativeRotation, Socket->RelativeLocation, Socket->RelativeScale );

			// Oculus has asymmetrical controllers, so we the sock transform horizontally
			if ( ControllerHandSide == EControllerHand::Right &&
				GetVRMode().GetHMDDeviceType() == EHMDDeviceType::DT_OculusRift )
			{
				const FVector Scale3D = SocketRelativeTransform.GetLocation();
				SocketRelativeTransform.SetLocation( FVector( Scale3D.X, -Scale3D.Y, Scale3D.Z ) );
			}

			// Make sure the labels stay the same size even when the world is scaled
			FTransform HandTransformWithWorldToMetersScaling = GetTransform();
			HandTransformWithWorldToMetersScaling.SetScale3D( HandTransformWithWorldToMetersScaling.GetScale3D() * FVector( GetVRMode().GetWorldScaleFactor() ) );

			// Position right on top of the controller itself
			FTransform FloatingTextTransform = SocketRelativeTransform * HandTransformWithWorldToMetersScaling;
			FloatingText->SetActorTransform( FloatingTextTransform );

			// Orientate it toward the viewer
			FloatingText->Update( HeadTransform.GetLocation() );

			// Update fade state
			FloatingText->SetOpacity( FadeAlpha );
		}
	}
}


UStaticMeshSocket* UVREditorMotionControllerInteractor::FindMeshSocketForKey( UStaticMesh* StaticMesh, const FKey Key )
{
	// @todo vreditor: Hard coded mapping of socket names (e.g. "Shoulder") to expected names of sockets in the static mesh
	FName SocketName = NAME_None;
	if ( Key == EKeys::MotionController_Left_Shoulder || Key == EKeys::MotionController_Right_Shoulder )
	{
		static FName ShoulderSocketName( "Shoulder" );
		SocketName = ShoulderSocketName;
	}
	else if ( Key == EKeys::MotionController_Left_Trigger || Key == EKeys::MotionController_Right_Trigger ||
		Key == VREditorKeyNames::MotionController_Left_FullyPressedTriggerAxis || Key == VREditorKeyNames::MotionController_Right_FullyPressedTriggerAxis ||
		Key == VREditorKeyNames::MotionController_Left_PressedTriggerAxis || Key == VREditorKeyNames::MotionController_Right_PressedTriggerAxis )
	{
		static FName TriggerSocketName( "Trigger" );
		SocketName = TriggerSocketName;
	}
	else if ( Key == EKeys::MotionController_Left_Grip1 || Key == EKeys::MotionController_Right_Grip1 )
	{
		static FName GripSocketName( "Grip" );
		SocketName = GripSocketName;
	}
	else if ( Key == EKeys::MotionController_Left_Thumbstick || Key == EKeys::MotionController_Right_Thumbstick )
	{
		static FName ThumbstickSocketName( "Thumbstick" );
		SocketName = ThumbstickSocketName;
	}
	else if ( Key == SteamVRControllerKeyNames::Touch0 || Key == SteamVRControllerKeyNames::Touch1 )
	{
		static FName TouchSocketName( "Touch" );
		SocketName = TouchSocketName;
	}
	else if ( Key == EKeys::MotionController_Left_Thumbstick_Down || Key == EKeys::MotionController_Right_Thumbstick_Down )
	{
		static FName DownSocketName( "Down" );
		SocketName = DownSocketName;
	}
	else if ( Key == EKeys::MotionController_Left_Thumbstick_Up || Key == EKeys::MotionController_Right_Thumbstick_Up )
	{
		static FName UpSocketName( "Up" );
		SocketName = UpSocketName;
	}
	else if ( Key == EKeys::MotionController_Left_Thumbstick_Left || Key == EKeys::MotionController_Right_Thumbstick_Left )
	{
		static FName LeftSocketName( "Left" );
		SocketName = LeftSocketName;
	}
	else if ( Key == EKeys::MotionController_Left_Thumbstick_Right || Key == EKeys::MotionController_Right_Thumbstick_Right )
	{
		static FName RightSocketName( "Right" );
		SocketName = RightSocketName;
	}
	else if ( Key == EKeys::MotionController_Left_FaceButton1 || Key == EKeys::MotionController_Right_FaceButton1 )
	{
		static FName FaceButton1SocketName( "FaceButton1" );
		SocketName = FaceButton1SocketName;
	}
	else if ( Key == EKeys::MotionController_Left_FaceButton2 || Key == EKeys::MotionController_Right_FaceButton2 )
	{
		static FName FaceButton2SocketName( "FaceButton2" );
		SocketName = FaceButton2SocketName;
	}
	else if ( Key == EKeys::MotionController_Left_FaceButton3 || Key == EKeys::MotionController_Right_FaceButton3 )
	{
		static FName FaceButton3SocketName( "FaceButton3" );
		SocketName = FaceButton3SocketName;
	}
	else if ( Key == EKeys::MotionController_Left_FaceButton4 || Key == EKeys::MotionController_Right_FaceButton4 )
	{
		static FName FaceButton4SocketName( "FaceButton4" );
		SocketName = FaceButton4SocketName;
	}
	else
	{
		// Not a key that we care about
	}

	if ( SocketName != NAME_None )
	{
		UStaticMeshSocket* Socket = StaticMesh->FindSocket( SocketName );
		if ( Socket != nullptr )
		{
			return Socket;
		}
	}

	return nullptr;
};

void UVREditorMotionControllerInteractor::UpdateSplineLaser(const FVector& InStartLocation, const FVector& InEndLocation, const FVector& InForward)
{
	if (LaserSplineComponent)
	{
		// Clear the segments before updating it
		LaserSplineComponent->ClearSplinePoints(true);

		const FVector SmoothLaserDirection = InEndLocation - InStartLocation;
		float Distance = SmoothLaserDirection.Size();
		const FVector StraightLaserEndLocation = InStartLocation + (InForward * Distance);
		const int32 NumLaserSplinePoints = LaserSplineMeshComponents.Num();

		LaserSplineComponent->AddSplinePoint(InStartLocation, ESplineCoordinateSpace::World, false);
		for (int32 Index = 1; Index < NumLaserSplinePoints; Index++)
		{
			float Alpha = (float)Index / (float)NumLaserSplinePoints;
			Alpha = FMath::Sin(Alpha * PI * 0.5f);
			const FVector PointOnStraightLaser = FMath::Lerp(InStartLocation, StraightLaserEndLocation, Alpha);
			const FVector PointOnSmoothLaser = FMath::Lerp(InStartLocation, InEndLocation, Alpha);
			const FVector PointBetweenLasers = FMath::Lerp(PointOnStraightLaser, PointOnSmoothLaser, Alpha);
			LaserSplineComponent->AddSplinePoint(PointBetweenLasers, ESplineCoordinateSpace::World, false);
		}
		LaserSplineComponent->AddSplinePoint(InEndLocation, ESplineCoordinateSpace::World, false);

		// Update all the segments of the spline
		LaserSplineComponent->UpdateSpline();
		
		const float LaserPointerRadius = VREd::LaserPointerRadius->GetFloat() * VRMode->GetWorldScaleFactor();
		Distance *= 0.0001f;
		for (int32 Index = 0; Index < NumLaserSplinePoints; Index++)
		{
			USplineMeshComponent* SplineMeshComponent = LaserSplineMeshComponents[Index];
			check (SplineMeshComponent != nullptr);
			
			FVector StartLoc, StartTangent, EndLoc, EndTangent;
			LaserSplineComponent->GetLocationAndTangentAtSplinePoint(Index, StartLoc, StartTangent, ESplineCoordinateSpace::Local);
			LaserSplineComponent->GetLocationAndTangentAtSplinePoint(Index + 1, EndLoc, EndTangent, ESplineCoordinateSpace::Local);

			const float AlphaIndex = (float)Index / (float)NumLaserSplinePoints;
			const float AlphaDistance = Distance * AlphaIndex;
			float Radius = LaserPointerRadius * ((AlphaIndex * AlphaDistance) + 1);
			FVector2D LaserScale(Radius, Radius); 
			SplineMeshComponent->SetStartScale(LaserScale, false);
			
			const float NextAlphaIndex = (float)(Index + 1) / (float)NumLaserSplinePoints;
			const float NextAlphaDistance = Distance * NextAlphaIndex;
			Radius = LaserPointerRadius * ((NextAlphaIndex * NextAlphaDistance) + 1);
			LaserScale = FVector2D(Radius, Radius);
			SplineMeshComponent->SetEndScale(LaserScale, false);

			SplineMeshComponent->SetStartAndEnd(StartLoc, StartTangent, EndLoc, EndTangent, true);
		}
	}
}

void UVREditorMotionControllerInteractor::SetLaserVisibility(const bool bVisible)
{
	for (USplineMeshComponent* SplineMeshComponent : LaserSplineMeshComponents)
	{
		SplineMeshComponent->SetVisibility(bVisible);
	}
}

void UVREditorMotionControllerInteractor::SetLaserVisuals( const FLinearColor& NewColor, const float CrawlFade, const float CrawlSpeed )
{
	static FName StaticLaserColorParameterName( "LaserColor" );
	LaserPointerMID->SetVectorParameterValue( StaticLaserColorParameterName, NewColor );
	TranslucentLaserPointerMID->SetVectorParameterValue( StaticLaserColorParameterName, NewColor );

	static FName StaticCrawlParameterName( "Crawl" );
	LaserPointerMID->SetScalarParameterValue( StaticCrawlParameterName, CrawlFade );
	TranslucentLaserPointerMID->SetScalarParameterValue( StaticCrawlParameterName, CrawlFade );

	static FName StaticCrawlSpeedParameterName( "CrawlSpeed" );
	LaserPointerMID->SetScalarParameterValue( StaticCrawlSpeedParameterName, CrawlSpeed );
	TranslucentLaserPointerMID->SetScalarParameterValue( StaticCrawlSpeedParameterName, CrawlSpeed );

	static FName StaticHandTrimColorParameter( "TrimGlowColor" );
	HandMeshMID->SetVectorParameterValue( StaticHandTrimColorParameter, NewColor );

	HoverPointLightComponent->SetLightColor( NewColor );
}

void UVREditorMotionControllerInteractor::UpdateRadialMenuInput( const float DeltaTime )
{
	UVREditorUISystem& UISystem = GetVRMode().GetUISystem();
	const EHMDDeviceType::Type HMDDeviceType = GetVRMode().GetHMDDeviceType();
	//Update the radial menu
	EViewportInteractionDraggingMode DraggingMode = GetDraggingMode();
	if (ControllerType == EControllerType::UI)
	{
		if ((bIsTrackpadPositionValid[0] && bIsTrackpadPositionValid[1]) &&
			DraggingMode != EViewportInteractionDraggingMode::AssistingDrag)
		{
			if (bIsScrubbingSequence)
			{
				const FVector2D ReturnToCenter = FVector2D::ZeroVector;
				UISystem.GetRadialMenuFloatingUI()->HighlightSlot(ReturnToCenter);

				const float NewPlayRate = FMath::GetMappedRangeValueClamped(FVector2D(-1.0f, 1.0f), FVector2D(-1.0f*VREd::SequencerScrubMax->GetFloat(), VREd::SequencerScrubMax->GetFloat()), TrackpadPosition.X);
				FVREditorActionCallbacks::PlaySequenceAtRate(VRMode, NewPlayRate);
			}
			else
			{
				// Update the radial menu if we are already showing the radial menu
				if (UISystem.IsShowingRadialMenu(this))
				{
					if (UISystem.GetRadialMenuFloatingUI()->GetWidgetComponents().Num() > 0)
					{
						UISystem.GetRadialMenuFloatingUI()->HighlightSlot(TrackpadPosition);

						if (TrackpadPosition.GetAbsMax() > VREd::MinJoystickOffsetBeforeFlick->GetFloat())
						{
							LastActiveTrackpadUpdateTime = FTimespan::FromSeconds(FPlatformTime::Seconds());
						}
					}
				}
				else if (!UISystem.IsShowingRadialMenu(this) && 
					TrackpadPosition.GetAbsMax() > VREd::MinJoystickOffsetBeforeFlick->GetFloat())
				{
					const bool bForceRefresh = false;
					UISystem.TryToSpawnRadialMenu(this, bForceRefresh);
					LastActiveTrackpadUpdateTime = FTimespan::FromSeconds(FPlatformTime::Seconds());
				}
			}
		}
		// If we are not currently touching the Vive touchpad, reset the highlighted button
		else if (HMDDeviceType == EHMDDeviceType::DT_SteamVR && !bIsTouchingTrackpad)
		{
			if (UISystem.IsShowingRadialMenu(this))
			{
				const FVector2D ReturnToCenter = FVector2D::ZeroVector;
				UISystem.GetRadialMenuFloatingUI()->HighlightSlot(ReturnToCenter);
			}
		}
	}

	else if (ControllerType == EControllerType::Laser)
	{
		if (VRMode->GetHMDDeviceType() != EHMDDeviceType::DT_SteamVR &&
			(bIsTrackpadPositionValid[0] && bIsTrackpadPositionValid[1]) &&
			DraggingMode != EViewportInteractionDraggingMode::TransformablesWithGizmo &&
			DraggingMode != EViewportInteractionDraggingMode::TransformablesFreely &&
			DraggingMode != EViewportInteractionDraggingMode::TransformablesAtLaserImpact &&
			DraggingMode != EViewportInteractionDraggingMode::AssistingDrag &&
			!VRMode->IsAimingTeleport())
		{
			// Move thumbstick left to undo
			if (TrackpadPosition.X < -1 * VREd::MinJoystickOffsetBeforeFlick->GetFloat() && 
				bFlickActionExecuted == false && 
				!IsHoveringOverUI())
			{
				VRMode->GetWorldInteraction().Undo();
				bFlickActionExecuted = true;
			}
			// Move thumbstick right to redo
			if (TrackpadPosition.X > VREd::MinJoystickOffsetBeforeFlick->GetFloat() &&
				bFlickActionExecuted == false &&
				!IsHoveringOverUI())
			{
				VRMode->GetWorldInteraction().Redo();
				bFlickActionExecuted = true;
			}
			// Center to reset
			// TODO: Remove finger from touchpad to reset vive
			if (FMath::IsNearlyZero(TrackpadPosition.X) &&
				!IsHoveringOverUI())
			{
				bFlickActionExecuted = false;
			}
		}
	}
}

void UVREditorMotionControllerInteractor::UndoRedoFromSwipe(const ETouchSwipeDirection InSwipeDirection)
{
	EViewportInteractionDraggingMode DraggingMode = GetDraggingMode();
	if (ControllerType == EControllerType::Laser &&
		VRMode->GetHMDDeviceType() == EHMDDeviceType::DT_SteamVR && 
		DraggingMode != EViewportInteractionDraggingMode::TransformablesWithGizmo &&
		DraggingMode != EViewportInteractionDraggingMode::TransformablesFreely &&
		DraggingMode != EViewportInteractionDraggingMode::TransformablesAtLaserImpact &&
		DraggingMode != EViewportInteractionDraggingMode::AssistingDrag &&
		!VRMode->IsAimingTeleport())
	{
		if (InSwipeDirection == ETouchSwipeDirection::Left)
		{
			VRMode->GetWorldInteraction().Undo();
			bFlickActionExecuted = true;
		}
		else if (InSwipeDirection == ETouchSwipeDirection::Right)
		{
			VRMode->GetWorldInteraction().Redo();
			bFlickActionExecuted = true;
		}
	}
}

bool UVREditorMotionControllerInteractor::GetIsLaserBlocked() const
{
	return Super::GetIsLaserBlocked() || (ControllerType != EControllerType::Laser && ControllerType != EControllerType::AssistingLaser);
}

#undef LOCTEXT_NAMESPACE