#pragma once

#include "CoreMinimal.h"
#include "UI/DescentHudLayout.h"
#include "UI/NeuStyle.h"
#include "Widgets/DeclarativeSyntaxSupport.h"
#include "Widgets/SLeafWidget.h"

class UWorld;

/**
 * The HUD (DESIGN_UE.md section 8.5): one Slate widget that fills the viewport and paints every region of the layout
 * table from an FDescentHudModel. It never takes the mouse. The regions' rectangles come from FDescentHudLayout, the same
 * function the headless layout test and the `ui.widgets` state part use.
 */
class THEDESCENT_API SDescentHUD : public SLeafWidget
{
public:
	SLATE_BEGIN_ARGS(SDescentHUD) {}
		SLATE_ARGUMENT(TWeakObjectPtr<UWorld>, World)
		/** Returns the model to draw (null = draw nothing). Called every paint. */
		SLATE_ARGUMENT(TFunction<const FDescentHudModel*()>, Model)
	SLATE_END_ARGS()

	void Construct(const FArguments& InArgs);
	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) const override { return FVector2D::ZeroVector; }

	/** Paints a model with a layout, at the given time (seconds, for blinking). World may be null (no world markers then). */
	static void PaintModel(FNeuPainter& P, const FDescentHudModel& Model, const FDescentHudLayout& Layout, double TimeSeconds, UWorld* World);

private:
	TWeakObjectPtr<UWorld> World;
	TFunction<const FDescentHudModel*()> ModelFn;
};