// RadialSliceWidget.cpp

#include "RadialSliceWidget.h"
#include "Components/Image.h"
#include "Components/CanvasPanelSlot.h"
#include "Materials/MaterialInstanceDynamic.h"

void URadialSliceWidget::NativeConstruct()
{
    Super::NativeConstruct();
}

void URadialSliceWidget::Setup(UMaterialInterface* InSliceMaterial,
    float StartAngleDeg, float AngleSizeDeg, UTexture2D* Icon, bool bEnabled)
{
    bSliceEnabled = bEnabled;

    if (InSliceMaterial && WedgeImage)
    {
        WedgeMID = UMaterialInstanceDynamic::Create(InSliceMaterial, this);
        WedgeImage->SetBrushFromMaterial(WedgeMID);

        // Per-slice angular span (normalized 0..1). The material draws only the
        // arc between these two, so each slice is an independent wedge.
        WedgeMID->SetScalarParameterValue(TEXT("StartAngle"), StartAngleDeg / 360.f);
        WedgeMID->SetScalarParameterValue(TEXT("AngleSize"), AngleSizeDeg / 360.f);
        WedgeMID->SetScalarParameterValue(TEXT("Highlight"), 0.f);
        WedgeMID->SetScalarParameterValue(TEXT("Enabled"), bEnabled ? 1.f : 0.f);
    }

    if (IconImage)
    {
        if (Icon)
        {
            IconImage->SetBrushFromTexture(Icon);
        }
        IconImage->SetRenderOpacity(bEnabled ? 0.55f : 0.3f);

        // Push the icon out along this slice's centerline so it sits inside the
        // wedge rather than at the menu's center. Center angle is measured
        // clockwise from 12 o'clock, matching the wedge the material draws.
        const float CenterAngleDeg = StartAngleDeg + AngleSizeDeg * 0.5f;
        const float CenterAngleRad = FMath::DegreesToRadians(CenterAngleDeg);
        const float OffsetX = FMath::Sin(CenterAngleRad) * IconRadius;
        const float OffsetY = -FMath::Cos(CenterAngleRad) * IconRadius;

        if (UCanvasPanelSlot* IconSlot = Cast<UCanvasPanelSlot>(IconImage->Slot))
        {
            // Anchor + align to center so Position is relative to the menu's
            // middle; then offset out to the slice center.
            IconSlot->SetAnchors(FAnchors(0.5f, 0.5f));
            IconSlot->SetAlignment(FVector2D(0.5f, 0.5f));
            IconSlot->SetPosition(FVector2D(OffsetX, OffsetY));
        }
    }
}

void URadialSliceWidget::UpdateHighlight(bool bIsHovered, float UndilatedDelta)
{
    const float Target = (bIsHovered && bSliceEnabled) ? 1.f : 0.f;
    CurrentHighlight = FMath::FInterpTo(CurrentHighlight, Target,
        UndilatedDelta, HighlightInterpSpeed);

    if (WedgeMID)
    {
        WedgeMID->SetScalarParameterValue(TEXT("Highlight"), CurrentHighlight);
    }

    if (IconImage && bSliceEnabled)
    {
        // Icon brightens from its dim resting state up to full on hover.
        IconImage->SetRenderOpacity(FMath::Lerp(0.55f, 1.0f, CurrentHighlight));
    }
}