#pragma once

#include "CoreMinimal.h"
#include "Player/Arm/DescentArmPose.h"

/** The phases of the wall-plug sequence (DESIGN_UE.md 6.9; timing in Core/Tuning/DescentTune_Arm.h). */
enum class EDescentArmJackPhase : uint8
{
	Inactive,
	Raise,      // the arm comes up from where it was to the ready position
	Reach,      // the fingertips travel to the standoff point on the port's axis, the hand closes into the plug shape
	Plug,       // straight in along the port's axis until the plug seats
	Feed,       // the plug is seated; hold still while nutrition flows
	Withdraw,   // straight back out along the port's axis
	Lower,      // the arm goes back down to the pose it ends in
	Done,
};

/** What the sequence needs to know, all in ARM SPACE (origin = shoulder, +X along the arm, cm). */
struct FDescentArmJackInput
{
	/** The pose when the sequence began (the raise starts from it). */
	FDescentArmPose Start;
	/** The pose the arm lowers to at the end. */
	FDescentArmPose End;
	/** Where the middle fingertip must be when the plug is seated: the port's socket. */
	FVector PortCm = FVector::ZeroVector;
	/** Unit vector: the way the hand moves into the port (the port's outward normal, reversed). */
	FVector PlugDirection = FVector::ForwardVector;
};

struct FDescentArmJackFrame
{
	FDescentArmPose Pose;
	EDescentArmJackPhase Phase = EDescentArmJackPhase::Inactive;
	/** 0..1 inside the current phase. */
	double PhaseProgress = 0.0;
	/** True from the moment the plug seats until it is pulled (the nutrition flows during this window). */
	bool bFeeding = false;
	/** The reach solver's result for this frame: position error (cm), whether it is inside the stated accuracy, and how far the
	 *  hand is from the wanted direction (degrees). In Feed these are the jack-in's accuracy. */
	double ReachErrorCm = 0.0;
	bool bReachable = true;
	double HandDirErrorDeg = 0.0;
};

namespace Descent::Arm
{
	THEDESCENT_API const TCHAR* JackPhaseName(EDescentArmJackPhase Phase);
	/** The phase at time T (seconds from the start) for the timing in the tuning header. */
	THEDESCENT_API EDescentArmJackPhase JackPhaseAt(double T);
	/**
	 * The arm at time T of the sequence. A pure function of (T, input): the same call always gives the same answer, so
	 * the component can re-evaluate it every frame against a port that moves with the camera.
	 */
	THEDESCENT_API FDescentArmJackFrame EvaluateJack(double T, const FDescentArmJackInput& Input);
}