#pragma once

#include "CoreMinimal.h"
#include "GameFramework/Actor.h"
#include "Core/DescentHandle.h"
#include "Core/DescentWorldSubsystem.h"
#include "UI/ViewModels/DashViewModel.h"
#include "Vehicles/CarrierHelm.h"
#include "DescentCarrier.generated.h"

class UCarrierBlockoutComponent;
class UCameraComponent;
class UDescentDashComponent;
class UCarrierCarouselComponent;
class ADescentCarrier;

/** Finds the one carrier of a world (set by the carrier's BeginPlay). */
UCLASS()
class THEDESCENT_API UDescentCarrierSubsystem : public UDescentWorldSubsystem
{
	GENERATED_BODY()

public:
	static ADescentCarrier* GetCarrier(const UWorld* World);
	TWeakObjectPtr<ADescentCarrier> Carrier;
};

/**
 * A kinematic motion for tests (R2, DESIGN_UE.md section 11): the carrier translates along its own axes, yaws at a constant rate and
 * pitches as a sine, in sim step 2. The real helm (M6) replaces it; the base-following it exercises is the same.
 */
struct FCarrierDebugMotion
{
	bool bActive = false;
	FVector VelocityLocalMps = FVector::ZeroVector;   // along the carrier's own axes (x = forward)
	double YawRateDps = 0.0;
	double PitchAmplitudeDeg = 0.0;
	double PitchPeriodSec = 10.0;
	double RemainingSec = 0.0;
	double ElapsedSec = 0.0;
};

/**
 * CANTICLE (DESIGN_UE.md section 3). At M2 it is the procedural blockout (UCarrierBlockoutComponent), the dry volume (U5, U6), the
 * stream focus, fixtures, the `carrier` state section and the debug motion; the helm physics, carousel and systems arrive later.
 */
UCLASS()
class THEDESCENT_API ADescentCarrier : public AActor
{
	GENERATED_BODY()

public:
	ADescentCarrier();

	virtual void BeginPlay() override;
	virtual void EndPlay(const EEndPlayReason::Type Reason) override;
	virtual void Tick(float DeltaSeconds) override;

	UPROPERTY(VisibleAnywhere) TObjectPtr<UCarrierBlockoutComponent> Blockout;
	/** Section 3.5: sub bay carousel, hoist and the three Tenders (M3). */
	UPROPERTY(VisibleAnywhere) TObjectPtr<UCarrierCarouselComponent> Carousel;

	/** Section 3.3: the single dry/wet answer; the environment, fauna and the temperature readouts all key off it. */
	bool IsDry(const FVector& LocalM) const;
	FVector ToLocalM(const FVector& WorldUU) const { return GetActorTransform().InverseTransformPosition(WorldUU) / 100.0; }
	FVector ToWorldUU(const FVector& LocalM) const { return GetActorTransform().TransformPosition(LocalM * 100.0); }

	/** Debug motion (Descent.Carrier.Motion): stops itself after Seconds. */
	void SetDebugMotion(const FCarrierDebugMotion& Motion);
	void ClearDebugMotion();
	const FCarrierDebugMotion& GetDebugMotion() const { return DebugMotion; }

	// ---- the helm (section 3.6; M6: U4, U9, V12) ----
	FCarrierHelmState Helm;
	FCarrierAutopilot Autopilot;
	/** Somebody (the player in mode Helm, or Descent.Carrier.Helm 1) holds the helm. Released, the carrier comes to an all stop. */
	void SetHelmHeld(bool bHeld);
	bool IsHelmHeld() const { return bHelmHeld; }
	/** 0 BRIDGE, 1 CHASE, 2 TOP-DOWN, 3 BOW CAM, 4 KEEL CAM. */
	void SetHelmView(int32 View);
	int32 GetHelmView() const { return HelmView; }
	/** Moves the carrier and everything attached to it (debug). */
	void TeleportCarrier(const FVector& PosM, double YawDeg);
	/** The helm dash: the Tender's widget fed with the carrier's numbers (V6). */
	FTenderDashModel MakeDashModel() const;
	struct FProximityRow { FString Label; double DistanceM = 0.0; };
	TArray<FProximityRow> Proximity;
	UPROPERTY(VisibleAnywhere) TObjectPtr<UCameraComponent> HelmCamera;
	UPROPERTY(Transient) TObjectPtr<UDescentDashComponent> HelmDash;

	FVector VelocityMps() const { return VelMps; }
	double YawRateDps() const { return YawRateDpsMeasured; }

private:
	void SimStep(double Dt);

	FDescentHandle DryHandle;
	FDescentHandle StepHandle;
	FCarrierDebugMotion DebugMotion;
	double BaseYawDeg = 0.0;
	FVector VelMps = FVector::ZeroVector;
	double YawRateDpsMeasured = 0.0;
	bool bHelmHeld = false;
	int32 HelmView = 0;
	double ProximityTimer = 0.0;
	FDescentHandle DashHandle;
	void UpdateProximity();
};