// Copyright IHY. Universal Bars plugin.
#include "UniversalBarWidget.h"
#include "Components/Image.h"
#include "Materials/MaterialInstanceDynamic.h"

UUniversalBarWidget::UUniversalBarWidget(const FObjectInitializer& ObjectInitializer)
	: Super(ObjectInitializer)
{
}

void UUniversalBarWidget::NativeConstruct()
{
	Super::NativeConstruct();
	EnsureMID();
	if (BarMID)
	{
		BarMID->SetScalarParameterValue(TEXT("FillPercent"), DisplayFill);
		BarMID->SetScalarParameterValue(TEXT("DelayedFillPercent"), DelayedFill);
	}
	PushZones(true);
}

UMaterialInstanceDynamic* UUniversalBarWidget::EnsureMID()
{
	if (BarMID || !BarImage)
	{
		return BarMID;
	}
	BarMID = BarImage->GetDynamicMaterial();
	return BarMID;
}

void UUniversalBarWidget::SetFillPercent(float NewValue, bool bAnimate)
{
	EnsureMID();
	NewValue = FMath::Clamp(NewValue, 0.f, 1.f);

	if (!bAnimate)
	{
		TargetFill = DisplayFill = DelayedFill = NewValue;
		if (BarMID)
		{
			BarMID->SetScalarParameterValue(TEXT("FillPercent"), DisplayFill);
			BarMID->SetScalarParameterValue(TEXT("DelayedFillPercent"), DelayedFill);
		}
		return;
	}

	const bool bDown = NewValue < TargetFill - KINDA_SMALL_NUMBER;
	const bool bUp   = NewValue > TargetFill + KINDA_SMALL_NUMBER;
	TargetFill = NewValue;

	if (bDown)
	{
		// instant bright drop; the lighter tail holds, then drains (damage lag)
		DisplayFill = NewValue;
		DelayTimer = DelayedDelay;
		if (BarMID)
		{
			BarMID->SetScalarParameterValue(TEXT("FillPercent"), DisplayFill);
		}
		if (bAutoFlashOnChange)
		{
			PlayDamageFlash();
		}
	}
	else if (bUp)
	{
		// show the incoming amount immediately as the lighter band; bright fill eases up into it
		DelayedFill = FMath::Max(DelayedFill, NewValue);
		if (BarMID)
		{
			BarMID->SetScalarParameterValue(TEXT("DelayedFillPercent"), DelayedFill);
		}
		if (bAutoFlashOnChange)
		{
			PlayHealFlash();
		}
	}
}

void UUniversalBarWidget::SetShieldPercent(float NewValue)
{
	EnsureMID();
	if (BarMID)
	{
		BarMID->SetScalarParameterValue(TEXT("ShieldPercent"), FMath::Clamp(NewValue, 0.f, 1.f));
	}
}

void UUniversalBarWidget::PlayDamageFlash()
{
	PlayFlash(DamageFlashColor);
}

void UUniversalBarWidget::PlayHealFlash()
{
	PlayFlash(HealFlashColor);
}

void UUniversalBarWidget::PlayFlash(FLinearColor Color)
{
	EnsureMID();
	PendingFlashColor = Color;
	if (BarMID)
	{
		BarMID->SetVectorParameterValue(TEXT("FlashColor"), Color);
	}
	FlashAmount = 1.f;
	bFlashing = true;
}

void UUniversalBarWidget::SetBarColors(FLinearColor Fill, FLinearColor Empty, FLinearColor Border, FLinearColor Delayed)
{
	EnsureMID();
	if (!BarMID)
	{
		return;
	}
	BarMID->SetVectorParameterValue(TEXT("FillColor"), Fill);
	BarMID->SetVectorParameterValue(TEXT("EmptyColor"), Empty);
	BarMID->SetVectorParameterValue(TEXT("BorderColor"), Border);
	BarMID->SetVectorParameterValue(TEXT("DelayedFillColor"), Delayed);
}

void UUniversalBarWidget::SetSegmentCount(int32 Count)
{
	EnsureMID();
	if (!BarMID)
	{
		return;
	}
	BarMID->SetScalarParameterValue(TEXT("SegmentCount"), static_cast<float>(FMath::Max(0, Count)));
	BarMID->SetScalarParameterValue(TEXT("SegmentDividerOpacity"), Count > 0 ? 0.85f : 0.f);
}

void UUniversalBarWidget::SetPenaltyZone(FName Id, float Width, FLinearColor Color)
{
	Width = FMath::Clamp(Width, 0.f, 1.f);
	for (FBarZone& Zone : PenaltyZones)
	{
		if (Zone.Id == Id)
		{
			Zone.Width = Width;
			Zone.Color = Color;
			return; // tick eases DisplayWidth toward the new Width
		}
	}
	FBarZone& NewZone = PenaltyZones[PenaltyZones.AddDefaulted()];
	NewZone.Id = Id;
	NewZone.Width = Width;
	NewZone.Color = Color;
}

void UUniversalBarWidget::SetPenaltyZoneWidth(FName Id, float Width)
{
	Width = FMath::Clamp(Width, 0.f, 1.f);
	for (FBarZone& Zone : PenaltyZones)
	{
		if (Zone.Id == Id)
		{
			Zone.Width = Width;
			return;
		}
	}
}

void UUniversalBarWidget::RemovePenaltyZone(FName Id)
{
	// Ease to zero, then drop on next tick when fully collapsed.
	for (FBarZone& Zone : PenaltyZones)
	{
		if (Zone.Id == Id)
		{
			Zone.Width = 0.f;
			return;
		}
	}
}

void UUniversalBarWidget::ClearPenaltyZones()
{
	for (FBarZone& Zone : PenaltyZones)
	{
		Zone.Width = 0.f;
	}
}

void UUniversalBarWidget::PushZones(bool bImmediate)
{
	EnsureMID();
	if (!BarMID)
	{
		return;
	}

	const int32 Count = FMath::Min(PenaltyZones.Num(), MaxMaterialZones);
	float Total = 0.f;
	for (int32 i = 0; i < Count; ++i)
	{
		if (bImmediate)
		{
			PenaltyZones[i].DisplayWidth = PenaltyZones[i].Width;
		}
		Total += FMath::Clamp(PenaltyZones[i].DisplayWidth, 0.f, 1.f);
	}
	Total = FMath::Clamp(Total, 0.f, 1.f);

	const float MaxFill = 1.f - Total;
	BarMID->SetScalarParameterValue(TEXT("MaxFillPercent"), MaxFill);
	BarMID->SetScalarParameterValue(TEXT("PenaltyCount"), static_cast<float>(Count));

	float Bound = MaxFill;
	static const TCHAR* EndNames[MaxMaterialZones]   = { TEXT("PenaltyEnd1"), TEXT("PenaltyEnd2"), TEXT("PenaltyEnd3"), TEXT("PenaltyEnd4") };
	static const TCHAR* ColorNames[MaxMaterialZones] = { TEXT("PenaltyColor1"), TEXT("PenaltyColor2"), TEXT("PenaltyColor3"), TEXT("PenaltyColor4") };
	for (int32 i = 0; i < MaxMaterialZones; ++i)
	{
		if (i < Count)
		{
			Bound = FMath::Min(1.f, Bound + FMath::Clamp(PenaltyZones[i].DisplayWidth, 0.f, 1.f));
			BarMID->SetScalarParameterValue(EndNames[i], Bound);
			BarMID->SetVectorParameterValue(ColorNames[i], PenaltyZones[i].Color);
		}
		else
		{
			BarMID->SetScalarParameterValue(EndNames[i], 1.f);
		}
	}
}

float UUniversalBarWidget::GetUsableEnd() const
{
	float Total = 0.f;
	const int32 N = FMath::Min(PenaltyZones.Num(), MaxMaterialZones);
	for (int32 i = 0; i < N; ++i)
	{
		Total += FMath::Clamp(PenaltyZones[i].DisplayWidth, 0.f, 1.f);
	}
	return FMath::Clamp(1.f - Total, 0.f, 1.f);
}

float UUniversalBarWidget::GetZoneCenter(FName Id) const
{
	float Edge = GetUsableEnd();
	const int32 N = FMath::Min(PenaltyZones.Num(), MaxMaterialZones);
	for (int32 i = 0; i < N; ++i)
	{
		const float W = FMath::Clamp(PenaltyZones[i].DisplayWidth, 0.f, 1.f);
		if (PenaltyZones[i].Id == Id)
		{
			return Edge + W * 0.5f;
		}
		Edge += W;
	}
	return -1.f;
}

void UUniversalBarWidget::SetScalar(FName Param, float Value)
{
	EnsureMID();
	if (BarMID) { BarMID->SetScalarParameterValue(Param, Value); }
}

void UUniversalBarWidget::SetVector(FName Param, FLinearColor Value)
{
	EnsureMID();
	if (BarMID) { BarMID->SetVectorParameterValue(Param, Value); }
}

void UUniversalBarWidget::NativeTick(const FGeometry& MyGeometry, float InDeltaTime)
{
	Super::NativeTick(MyGeometry, InDeltaTime);
	if (!BarMID)
	{
		return;
	}

	// bright fill eases toward target (smooth rise on heal; already snapped on damage)
	if (!FMath::IsNearlyEqual(DisplayFill, TargetFill, 1e-3f))
	{
		DisplayFill = FMath::FInterpTo(DisplayFill, TargetFill, InDeltaTime, FillRiseSpeed);
		BarMID->SetScalarParameterValue(TEXT("FillPercent"), DisplayFill);
	}

	// lighter "lag" tail: holds, then drains toward target (damage). Never below the bright fill.
	const float DelayedTarget = FMath::Max(TargetFill, DisplayFill);
	if (!FMath::IsNearlyEqual(DelayedFill, DelayedTarget, 1e-3f))
	{
		if (DelayTimer > 0.f)
		{
			DelayTimer -= InDeltaTime;
		}
		else
		{
			DelayedFill = FMath::FInterpTo(DelayedFill, DelayedTarget, InDeltaTime, DelayedFallSpeed);
			BarMID->SetScalarParameterValue(TEXT("DelayedFillPercent"), DelayedFill);
		}
	}

	// flash decay
	if (bFlashing)
	{
		FlashAmount = FMath::FInterpTo(FlashAmount, 0.f, InDeltaTime, FlashSpeed);
		BarMID->SetScalarParameterValue(TEXT("FlashAmount"), FlashAmount);
		if (FlashAmount < 0.01f)
		{
			FlashAmount = 0.f;
			bFlashing = false;
			BarMID->SetScalarParameterValue(TEXT("FlashAmount"), 0.f);
		}
	}

	// low-value pulse
	const float PulseTarget = (TargetFill < LowThreshold) ? 1.f : 0.f;
	if (!FMath::IsNearlyEqual(PulseAmount, PulseTarget, 1e-3f))
	{
		PulseAmount = FMath::FInterpTo(PulseAmount, PulseTarget, InDeltaTime, 6.f);
		BarMID->SetScalarParameterValue(TEXT("LowHPPulseAmount"), PulseAmount);
	}

	// penalty zone widths ease toward target; drop fully-collapsed removed zones
	bool bZonesDirty = false;
	bool bNeedCompact = false;
	for (FBarZone& Zone : PenaltyZones)
	{
		if (!FMath::IsNearlyEqual(Zone.DisplayWidth, Zone.Width, 1e-4f))
		{
			Zone.DisplayWidth = FMath::FInterpTo(Zone.DisplayWidth, Zone.Width, InDeltaTime, ZoneInterpSpeed);
			bZonesDirty = true;
		}
		if (Zone.Width <= 0.f && Zone.DisplayWidth <= 1e-3f)
		{
			bNeedCompact = true;
		}
	}
	if (bZonesDirty)
	{
		PushZones(false);
	}
	if (bNeedCompact)
	{
		PenaltyZones.RemoveAll([](const FBarZone& Z) { return Z.Width <= 0.f && Z.DisplayWidth <= 1e-3f; });
		PushZones(false);
	}
}