#pragma once

#include "CoreMinimal.h"
#include "GameFramework/Actor.h"
#include "Core/DescentHandle.h"
#include "Core/DescentWorldSubsystem.h"
#include "Player/DescentInteraction.h"
#include "KazahTender.generated.h"

class UBoxComponent;
class UCameraComponent;
class UDescentDashComponent;
class UMaterialInstanceDynamic;
class UPointLightComponent;
class UStaticMeshComponent;
class USpotLightComponent;
class UTenderFlightComponent;
class AKazahTender;

/** One exported part of the Tender. The table of these is generated by Tools/blender/export_kazah.py. */
struct FKazahPartDef
{
	/** Component name and Blender object name: "Rotor_Port", "Canopy_Glass", ... */
	const TCHAR* Name;
	/** Asset under /Game/Vehicles/Kazah/, e.g. "SM_Kazah_Rotor_Port". */
	const TCHAR* MeshAsset;
	/** Where the part's pivot sits in the vehicle, cm, Unreal axes (+X forward, +Y right, +Z up). */
	FVector PivotCm;
	/** Bounds of the part's mesh around its pivot, cm. Used by tests to catch a bad re-export. */
	FVector LocalBoundsMinCm;
	FVector LocalBoundsMaxCm;
};

/**
 * The fleet (DESIGN_UE.md section 1.4, sim step 4): steps every Tender that belongs to the game (flight of the piloted one, drift of
 * abandoned ones, recharge in a cradle) and feeds the cockpit dashboards in the Dashboards late step. Tenders that are only looked at
 * (the showcase rig) are not in it.
 */
UCLASS()
class THEDESCENT_API UDescentTenderFleet : public UDescentWorldSubsystem
{
	GENERATED_BODY()

public:
	static UDescentTenderFleet* Get(const UWorld* World);

	virtual void OnWorldBeginPlay(UWorld& InWorld) override;
	virtual void Deinitialize() override;

	void Add(AKazahTender* T);
	const TArray<TWeakObjectPtr<AKazahTender>>& All() const { return Tenders; }
	AKazahTender* At(int32 Index) const { return Tenders.IsValidIndex(Index) ? Tenders[Index].Get() : nullptr; }

	/** The Tender the player flies right now (state Piloted), or null. Set by the player controller. */
	TWeakObjectPtr<AKazahTender> Piloted;
	/** The speed penalty of hunger (section 5.8); 1 until nutrition exists (M8). */
	double HungerMul = 1.0;

private:
	TArray<TWeakObjectPtr<AKazahTender>> Tenders;
	FDescentHandle StepHandle, DashHandle, ToolHandle;
};

/**
 * The small submarine ("Subtub", the Kazah Tender), DESIGN_UE.md section 4. It assembles the imported parts as components and, when it
 * belongs to the fleet (InitFleet), flies: flight component, collision boxes against the player, headlamp, cockpit camera and
 * dashboards, lids, beacon, paint.
 *
 * Frame: +X forward (the nose), +Y starboard (right), +Z up. The origin is the Blender file's world origin:
 * 3.73 m behind the tip of the nose, 3.26 m ahead of the tail, 0.97 m above the keel and 1.55 m below the top of
 * the hatch collar. 6.99 m long, 3.27 m wide, 2.51 m tall.
 *
 * Each moving part is its own component whose origin is on its axis of motion:
 *   Rotor_Port / Rotor_Stbd   spin about the X axis (roll) through the hub; they counter-rotate
 *   Canopy_Lid, Canopy_Glass  share one hinge line (lateral, Y axis) at the rear-bottom edge of the lid
 *   Hatch_Lid                 hinge line at the aft edge of the roof hatch
 *   Tool_Housing, Nose_Lens, Chin_Sensor   pivot at their centres
 * The meshes come from /Game/Vehicles/Kazah/ (created by Tools/import_assets.ps1); a missing mesh is logged
 * once and the part is simply absent.
 */
UCLASS()
class THEDESCENT_API AKazahTender : public AActor, public IDescentInteractable
{
	GENERATED_BODY()

public:
	AKazahTender();

	virtual void OnConstruction(const FTransform& Transform) override;
	virtual void Tick(float DeltaSeconds) override;
	virtual void EndPlay(const EEndPlayReason::Type Reason) override;

	/** Revolutions per minute of the rotors (the port one turns the opposite way). 0 stops them. A fleet Tender sets it from its thrust. */
	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Tender|Propulsion", meta = (ClampMin = "-3000", ClampMax = "3000"))
	float RotorRPM = 420.f;

	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Tender|Headlight")
	bool bHeadlightOn = true;

	/** Multiplies the start intensity of the Tender headlamp of DESIGN 7.5 (3.2, set up by Descent::Look::ConfigureSpot); the horror flicker uses it. */
	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Tender|Headlight", meta = (ClampMin = "0"))
	float HeadlightIntensityScale = 1.f;

	UFUNCTION(BlueprintCallable, Category = "Tender|Headlight")
	void SetHeadlight(bool bOn);

	UFUNCTION(BlueprintPure, Category = "Tender|Propulsion")
	float GetRotorAngleDeg() const { return RotorAngleDeg; }

	/** Degrees the rotors have turned in total since spawn (not wrapped); a scenario can assert it grew. */
	UFUNCTION(BlueprintPure, Category = "Tender|Propulsion")
	double GetRotorTotalDeg() const { return RotorTotalDeg; }

	/** Advances the rotor pose by DeltaSeconds as Tick would. Public so tests can drive it without a world. */
	void AdvanceRotors(float DeltaSeconds);

	UStaticMeshComponent* GetPart(FName PartName) const;

	/** The generated part table. */
	static TConstArrayView<FKazahPartDef> GetPartDefs();
	static FVector GetModelBoundsMinCm();
	static FVector GetModelBoundsMaxCm();

	// ---- the flying Tender (M3) ----------------------------------------------------------------------------------
	UPROPERTY(VisibleAnywhere) TObjectPtr<UTenderFlightComponent> Flight;
	UPROPERTY(VisibleAnywhere) TObjectPtr<UCameraComponent> CockpitCamera;

	/** Makes this Tender number Index of the fleet: spec, paint, dashboards, interaction, rotors driven by thrust. */
	void InitFleet(int32 Index);
	int32 GetFleetIndex() const { return FleetIndex; }

	/** In the bay: lit by the bay lamps (channel 1) and "dry" for the water post-process (stencil 1). At sea: channel 0, no stencil. */
	void SetInBay(bool bIn);
	bool IsInBay() const { return bInBay; }

	void SetCanopyOpen(bool bOpen) { bCanopyTarget = bOpen; }
	void SetHatchOpen(bool bOpen) { bHatchTarget = bOpen; }
	double GetCanopyOpen01() const { return Canopy01; }
	double GetHatchOpen01() const { return Hatch01; }
	/** Docked: the pilot looks around the cockpit (degrees, clamped to section 4.6). Zero looks along the nose. */
	void SetCockpitLook(double YawDeg, double PitchDeg);
	FVector2D GetCockpitLook() const { return CockpitLook; }
	/** Writes the dashboards from the flight component's model (Dashboards late step). */
	void UpdateDashboards();
	UDescentDashComponent* GetDashMain() const { return DashMain; }
	UDescentDashComponent* GetDashCargo() const { return DashCargo; }

	FVector ToWorldUU(const FVector& LocalM) const { return GetActorTransform().TransformPosition(LocalM * 100.0); }

	// ---- IDescentInteractable: E on foot boards the Tender that hangs at BOARD ----
	virtual FString GetPrompt() const override;
	virtual FVector GetFocusPointUU() const override;
	virtual double GetRangeM() const override;
	virtual double GetMinDot() const override { return 0.3; }
	virtual void Use(ADescentCharacter* User) override;

private:
	void ApplyRotorPose();
	void ApplyHeadlight();
	void ApplyLids();
	void ApplyRenderChannels();

	UPROPERTY()
	TObjectPtr<USceneComponent> Root;

	UPROPERTY()
	TMap<FName, TObjectPtr<UStaticMeshComponent>> Parts;

	UPROPERTY()
	TObjectPtr<USpotLightComponent> Headlight;

	UPROPERTY() TObjectPtr<UPointLightComponent> CockpitGlow;
	/** The glow at the point the drill bites (section 4.5): colour (1.0, 0.8, 0.55), radius 9 m; white on dense basalt. */
	UPROPERTY() TObjectPtr<UPointLightComponent> DrillGlow;
	UPROPERTY() TObjectPtr<UStaticMeshComponent> Beacon;
	UPROPERTY() TArray<TObjectPtr<UBoxComponent>> CollisionBoxes;
	UPROPERTY(Transient) TObjectPtr<UDescentDashComponent> DashMain;
	UPROPERTY(Transient) TObjectPtr<UDescentDashComponent> DashCargo;
	UPROPERTY(Transient) TObjectPtr<UMaterialInstanceDynamic> LensMID;
	UPROPERTY(Transient) TObjectPtr<UMaterialInstanceDynamic> BeaconMID;

	float RotorAngleDeg = 0.f;
	double RotorTotalDeg = 0.0;
	bool bLoggedMissingMesh = false;

	int32 FleetIndex = -1;
	bool bInBay = false;
	bool bCanopyTarget = false, bHatchTarget = false;
	double Canopy01 = 0.0, Hatch01 = 0.0;
	FVector2D CockpitLook = FVector2D::ZeroVector;
	double BeaconClock = 0.0;
	bool bLensOn = true;
};