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#pragma once

#include "../../HealthAndArmingChecks/HealthAndArmingChecks.hpp"
#include <drivers/drv_hrt.h>
#include <px4_platform_common/events.h>
#include <uORB/topics/actuator_armed.h>
#include <uORB/topics/vehicle_control_mode.h>
#include <uORB/topics/vehicle_status.h>

typedef enum {
	TRANSITION_DENIED = -1,
	TRANSITION_NOT_CHANGED = 0,
	TRANSITION_CHANGED
} transition_result_t;

using arm_disarm_reason_t = events::px4::enums::arm_disarm_reason_t;

class ArmStateMachine
{
public:
	ArmStateMachine() = default;
	~ArmStateMachine() = default;

	void forceArmState(uint8_t new_arm_state) { _arm_state = new_arm_state; }

	transition_result_t
	arming_state_transition(vehicle_status_s &status, const arming_state_t new_arming_state,
				actuator_armed_s &armed, HealthAndArmingChecks &checks, const bool fRunPreArmChecks,
				orb_advert_t *mavlink_log_pub, arm_disarm_reason_t calling_reason);

	// Getters
	uint8_t getArmState() const { return _arm_state; }

	bool isInit() const { return (_arm_state == vehicle_status_s::ARMING_STATE_INIT); }
	bool isStandby() const { return (_arm_state == vehicle_status_s::ARMING_STATE_STANDBY); }
	bool isArmed() const { return (_arm_state == vehicle_status_s::ARMING_STATE_ARMED); }
	bool isShutdown() const { return (_arm_state == vehicle_status_s::ARMING_STATE_SHUTDOWN); }

	static const char *getArmStateName(uint8_t arming_state);
	const char *getArmStateName() const { return getArmStateName(_arm_state); }

private:
	static inline events::px4::enums::arming_state_t getArmStateEvent(uint8_t arming_state);

	uint8_t _arm_state{vehicle_status_s::ARMING_STATE_INIT};

	// This array defines the arming state transitions. The rows are the new state, and the columns
	// are the current state. Using new state and current state you can index into the array which
	// will be true for a valid transition or false for a invalid transition. In some cases even
	// though the transition is marked as true additional checks must be made. See arming_state_transition
	// code for those checks.
	static constexpr bool arming_transitions[vehicle_status_s::ARMING_STATE_MAX][vehicle_status_s::ARMING_STATE_MAX]
	= {
		//                                                    INIT,  STANDBY, ARMED, STANDBY_ERROR, SHUTDOWN, IN_AIR_RESTORE
		{ /* vehicle_status_s::ARMING_STATE_INIT */           true,  true,    false, true,          false,    false },
		{ /* vehicle_status_s::ARMING_STATE_STANDBY */        true,  true,    true,  false,         false,    false },
		{ /* vehicle_status_s::ARMING_STATE_ARMED */          false, true,    true,  false,         false,    true },
		{ /* vehicle_status_s::ARMING_STATE_STANDBY_ERROR */  true,  true,    true,  true,          false,    false },
		{ /* vehicle_status_s::ARMING_STATE_SHUTDOWN */       true,  true,    false, true,          true,     true },
		{ /* vehicle_status_s::ARMING_STATE_IN_AIR_RESTORE */ false, false,   false, false,         false,    false }, // NYI
	};
};