#pragma once
#include "PixelShaderViewer.h"
#include "PeakFile/PeakFile.h"
#include "PluginHost/Sampler.h"

class FSamplePatternInstance;

class IWaveformHandle
{
public:
	virtual ~IWaveformHandle() = default;
	virtual TArrayView<const FSamplePeak> GetWaveform(int32 SizeX) = 0;
	virtual bool NeedUpdate() const { return false; }
	DECLARE_MULTICAST_DELEGATE(FRequestUpdate)
	FRequestUpdate OnRequestUpdate;
};

class ARONA_API SWaveformViewer : public SLeafWidget
{
public:
	SWaveformViewer();
	SLATE_BEGIN_ARGS(SWaveformViewer)
	{
	}
	SLATE_ARGUMENT(TSharedPtr<IWaveformHandle>, WaveformHandle)
	SLATE_END_ARGS()

	/** Constructs this widget with InArgs */
	void Construct(const FArguments& InArgs);

	virtual void Tick(const FGeometry& AllottedGeometry, const double InCurrentTime, const float InDeltaTime) override;
	virtual int32 OnPaint(const FPaintArgs& Args, const FGeometry& AllottedGeometry, const FSlateRect& MyCullingRect, FSlateWindowElementList& OutDrawElements, int32 LayerId, const FWidgetStyle& InWidgetStyle, bool bParentEnabled) const override;
	virtual FVector2D ComputeDesiredSize(float LayoutScaleMultiplier) const override { return RenderTarget->GetSize(); }
private:
	TSharedPtr<FSlateRenderTarget> RenderTarget;
	TSharedPtr<FSlateComputeShader> ComputeShader;
	TSharedPtr<FSlateShaderParam> Params;
	TSharedPtr<IComputeShaderSlateElement> ComputeElement;

	struct FCSParam
	{
		FLinearColor WaveColor;
		FLinearColor BgColor;
		float LineUV;
		float PeaksPerPixel;
	} mutable Param;
	TSharedPtr<IWaveformHandle> WaveformHandle;
};