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   *
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   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
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   *    used to endorse or promote products derived from this software
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   ****************************************************************************/
  
  /**
   * @file rc_update.cpp
   *
   * @author Beat Kueng <beat-kueng@gmx.net>
   */
  
  #include "rc_update.h"
  
  using namespace time_literals;
  
  namespace RCUpdate
  {
  
  // TODO: find a better home for this
  static bool operator ==(const manual_control_switches_s &a, const manual_control_switches_s &b)
  {
  	return (a.mode_slot == b.mode_slot &&
  		a.mode_switch == b.mode_switch &&
  		a.return_switch == b.return_switch &&
  		a.posctl_switch == b.posctl_switch &&
  		a.loiter_switch == b.loiter_switch &&
  		a.acro_switch == b.acro_switch &&
  		a.offboard_switch == b.offboard_switch &&
  		a.kill_switch == b.kill_switch &&
  		a.arm_switch == b.arm_switch &&
  		a.transition_switch == b.transition_switch &&
  		a.gear_switch == b.gear_switch &&
  		a.stab_switch == b.stab_switch &&
  		a.man_switch == b.man_switch);
  }
  
  static bool operator !=(const manual_control_switches_s &a, const manual_control_switches_s &b) { return !(a == b); }
  
  
  RCUpdate::RCUpdate() :
  	ModuleParams(nullptr),
  	WorkItem(MODULE_NAME, px4::wq_configurations::hp_default)
  {
  	// initialize parameter handles
  	for (unsigned i = 0; i < RC_MAX_CHAN_COUNT; i++) {
  		char nbuf[16];
  
  		/* min values */
  		sprintf(nbuf, "RC%d_MIN", i + 1);
  		_parameter_handles.min[i] = param_find(nbuf);
  
  		/* trim values */
  		sprintf(nbuf, "RC%d_TRIM", i + 1);
  		_parameter_handles.trim[i] = param_find(nbuf);
  
  		/* max values */
  		sprintf(nbuf, "RC%d_MAX", i + 1);
  		_parameter_handles.max[i] = param_find(nbuf);
  
  		/* channel reverse */
  		sprintf(nbuf, "RC%d_REV", i + 1);
  		_parameter_handles.rev[i] = param_find(nbuf);
  
  		/* channel deadzone */
  		sprintf(nbuf, "RC%d_DZ", i + 1);
  		_parameter_handles.dz[i] = param_find(nbuf);
  	}
  
  	// RC to parameter mapping for changing parameters with RC
  	for (int i = 0; i < rc_parameter_map_s::RC_PARAM_MAP_NCHAN; i++) {
  		// shifted by 1 because param name starts at 1
  		char name[rc_parameter_map_s::PARAM_ID_LEN];
  		snprintf(name, rc_parameter_map_s::PARAM_ID_LEN, "RC_MAP_PARAM%d", i + 1);
  		_parameter_handles.rc_map_param[i] = param_find(name);
  	}
  
  	rc_parameter_map_poll(true /* forced */);
  
  	parameters_updated();
  }
  
  RCUpdate::~RCUpdate()
  {
  	perf_free(_loop_perf);
  	perf_free(_loop_interval_perf);
  	perf_free(_valid_data_interval_perf);
  }
  
  bool RCUpdate::init()
  {
  	if (!_input_rc_sub.registerCallback()) {
  		PX4_ERR("input_rc callback registration failed!");
  		return false;
  	}
  
  	return true;
  }
  
  void RCUpdate::parameters_updated()
  {
  	// rc values
  	for (unsigned int i = 0; i < RC_MAX_CHAN_COUNT; i++) {
  
  		float min = 0.f;
  		param_get(_parameter_handles.min[i], &min);
  		_parameters.min[i] = min;
  
  		float trim = 0.f;
  		param_get(_parameter_handles.trim[i], &trim);
  		_parameters.trim[i] = trim;
  
  		float max = 0.f;
  		param_get(_parameter_handles.max[i], &max);
  		_parameters.max[i] = max;
  
  		float rev = 0.f;
  		param_get(_parameter_handles.rev[i], &rev);
  		_parameters.rev[i] = (rev < 0.f);
  
  		float dz = 0.f;
  		param_get(_parameter_handles.dz[i], &dz);
  		_parameters.dz[i] = dz;
  	}
  
  	for (int i = 0; i < rc_parameter_map_s::RC_PARAM_MAP_NCHAN; i++) {
  		param_get(_parameter_handles.rc_map_param[i], &(_parameters.rc_map_param[i]));
  	}
  
  	update_rc_functions();
  }
  
  void RCUpdate::update_rc_functions()
  {
  	/* update RC function mappings */
  	_rc.function[rc_channels_s::FUNCTION_THROTTLE] = _param_rc_map_throttle.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_ROLL] = _param_rc_map_roll.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_PITCH] = _param_rc_map_pitch.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_YAW] = _param_rc_map_yaw.get() - 1;
  
  	_rc.function[rc_channels_s::FUNCTION_MODE] = _param_rc_map_mode_sw.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_RETURN] = _param_rc_map_return_sw.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_POSCTL] = _param_rc_map_posctl_sw.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_LOITER] = _param_rc_map_loiter_sw.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_ACRO] = _param_rc_map_acro_sw.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_OFFBOARD] = _param_rc_map_offb_sw.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_KILLSWITCH] = _param_rc_map_kill_sw.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_ARMSWITCH] = _param_rc_map_arm_sw.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_TRANSITION] = _param_rc_map_trans_sw.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_GEAR] = _param_rc_map_gear_sw.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_STAB] = _param_rc_map_stab_sw.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_MAN] = _param_rc_map_man_sw.get() - 1;
  
  	_rc.function[rc_channels_s::FUNCTION_FLAPS] = _param_rc_map_flaps.get() - 1;
  
  	_rc.function[rc_channels_s::FUNCTION_AUX_1] = _param_rc_map_aux1.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_AUX_2] = _param_rc_map_aux2.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_AUX_3] = _param_rc_map_aux3.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_AUX_4] = _param_rc_map_aux4.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_AUX_5] = _param_rc_map_aux5.get() - 1;
  	_rc.function[rc_channels_s::FUNCTION_AUX_6] = _param_rc_map_aux6.get() - 1;
  
  	for (int i = 0; i < rc_parameter_map_s::RC_PARAM_MAP_NCHAN; i++) {
  		_rc.function[rc_channels_s::FUNCTION_PARAM_1 + i] = _parameters.rc_map_param[i] - 1;
  	}
  }
  
  void RCUpdate::rc_parameter_map_poll(bool forced)
  {
  	if (_rc_parameter_map_sub.updated() || forced) {
  		_rc_parameter_map_sub.copy(&_rc_parameter_map);
  
  		/* update parameter handles to which the RC channels are mapped */
  		for (int i = 0; i < rc_parameter_map_s::RC_PARAM_MAP_NCHAN; i++) {
  			if (_rc.function[rc_channels_s::FUNCTION_PARAM_1 + i] < 0 || !_rc_parameter_map.valid[i]) {
  				/* This RC channel is not mapped to a RC-Parameter Channel (e.g. RC_MAP_PARAM1 == 0)
  				 * or no request to map this channel to a param has been sent via mavlink
  				 */
  				continue;
  			}
  
  			/* Set the handle by index if the index is set, otherwise use the id */
  			if (_rc_parameter_map.param_index[i] >= 0) {
  				_parameter_handles.rc_param[i] = param_for_used_index((unsigned)_rc_parameter_map.param_index[i]);
  
  			} else {
  				_parameter_handles.rc_param[i] = param_find(&_rc_parameter_map.param_id[i * (rc_parameter_map_s::PARAM_ID_LEN + 1)]);
  			}
  		}
  
  		PX4_DEBUG("rc to parameter map updated");
  
  		for (int i = 0; i < rc_parameter_map_s::RC_PARAM_MAP_NCHAN; i++) {
  			PX4_DEBUG("\ti %d param_id %s scale %.3f value0 %.3f, min %.3f, max %.3f",
  				  i,
  				  &_rc_parameter_map.param_id[i * (rc_parameter_map_s::PARAM_ID_LEN + 1)],
  				  (double)_rc_parameter_map.scale[i],
  				  (double)_rc_parameter_map.value0[i],
  				  (double)_rc_parameter_map.value_min[i],
  				  (double)_rc_parameter_map.value_max[i]
  				 );
  		}
  	}
  }
  
  float RCUpdate::get_rc_value(uint8_t func, float min_value, float max_value) const
  {
  	if (_rc.function[func] >= 0) {
  		return math::constrain(_rc.channels[_rc.function[func]], min_value, max_value);
  	}
  
  	return 0.f;
  }
  
  void RCUpdate::set_params_from_rc()
  {
  	for (int i = 0; i < rc_parameter_map_s::RC_PARAM_MAP_NCHAN; i++) {
  		if (_rc.function[rc_channels_s::FUNCTION_PARAM_1 + i] < 0 || !_rc_parameter_map.valid[i]) {
  			/* This RC channel is not mapped to a RC-Parameter Channel (e.g. RC_MAP_PARAM1 == 0)
  			 * or no request to map this channel to a param has been sent via mavlink
  			 */
  			continue;
  		}
  
  		float rc_val = get_rc_value((rc_channels_s::FUNCTION_PARAM_1 + i), -1.f, 1.f);
  
  		/* Check if the value has changed,
  		 * maybe we need to introduce a more aggressive limit here */
  		if (rc_val > _param_rc_values[i] + FLT_EPSILON || rc_val < _param_rc_values[i] - FLT_EPSILON) {
  			_param_rc_values[i] = rc_val;
  			float param_val = math::constrain(
  						  _rc_parameter_map.value0[i] + _rc_parameter_map.scale[i] * rc_val,
  						  _rc_parameter_map.value_min[i], _rc_parameter_map.value_max[i]);
  
  			param_set(_parameter_handles.rc_param[i], &param_val);
  		}
  	}
  }
  
  void RCUpdate::Run()
  {
  	if (should_exit()) {
  		_input_rc_sub.unregisterCallback();
  		exit_and_cleanup();
  		return;
  	}
  
  	perf_begin(_loop_perf);
  	perf_count(_loop_interval_perf);
  
  	// check for parameter updates
  	if (_parameter_update_sub.updated()) {
  		// clear update
  		parameter_update_s pupdate;
  		_parameter_update_sub.copy(&pupdate);
  
  		// update parameters from storage
  		updateParams();
  		parameters_updated();
  	}
  
  	rc_parameter_map_poll();
  
  	/* read low-level values from FMU or IO RC inputs (PPM, Spektrum, S.Bus) */
  	input_rc_s input_rc;
  
  	if (_input_rc_sub.update(&input_rc)) {
  
  		// warn if the channel count is changing (possibly indication of error)
  		if (!input_rc.rc_lost) {
  			if ((_channel_count_previous != input_rc.channel_count)
  			    && (_channel_count_previous > 0)) {
  				PX4_WARN("channel count changed %d -> %d", _channel_count_previous, input_rc.channel_count);
  			}
  
  			if ((_input_source_previous != input_rc.input_source)
  			    && (_input_source_previous != input_rc_s::RC_INPUT_SOURCE_UNKNOWN)) {
  				PX4_WARN("input source changed %d -> %d", _input_source_previous, input_rc.input_source);
  			}
  		}
  
  		const bool input_source_stable = (input_rc.input_source == _input_source_previous);
  		const bool channel_count_stable = (input_rc.channel_count == _channel_count_previous);
  
  		_input_source_previous = input_rc.input_source;
  		_channel_count_previous = input_rc.channel_count;
  
  		const uint8_t channel_count_limited = math::min(input_rc.channel_count, RC_MAX_CHAN_COUNT);
  
  		if (channel_count_limited > _channel_count_max) {
  			_channel_count_max = channel_count_limited;
  		}
  
  		/* detect RC signal loss */
  		bool signal_lost = true;
  
  		/* check flags and require at least four channels to consider the signal valid */
  		if (input_rc.rc_lost || input_rc.rc_failsafe || input_rc.channel_count < 4) {
  			/* signal is lost or no enough channels */
  			signal_lost = true;
  
  		} else if ((input_rc.input_source == input_rc_s::RC_INPUT_SOURCE_PX4FMU_PPM ||
  			    input_rc.input_source == input_rc_s::RC_INPUT_SOURCE_PX4IO_PPM)
  			   && input_rc.channel_count == 16) {
  
  			// This is a specific RC lost check for RFD 868+/900 Modems on PPM.
  			// The observation was that when RC is lost, 16 channels are active and the first 12 are 1000
  			// and the remaining ones are 0.
  			for (unsigned int i = 0; i < 16; i++) {
  				if (i < 12 && input_rc.values[i] > 999 && input_rc.values[i] < 1005) {
  					signal_lost = true;
  
  				} else if (input_rc.values[i] == 0) {
  					signal_lost = true;
  
  				} else {
  					signal_lost = false;
  					break;
  				}
  			}
  
  		} else {
  			/* signal looks good */
  			signal_lost = false;
  
  			/* check failsafe */
  			int8_t fs_ch = _rc.function[_param_rc_map_failsafe.get()]; // get channel mapped to throttle
  
  			if (_param_rc_map_failsafe.get() > 0) { // if not 0, use channel number instead of rc.function mapping
  				fs_ch = _param_rc_map_failsafe.get() - 1;
  			}
  
  			if (_param_rc_fails_thr.get() > 0 && fs_ch >= 0) {
  				/* failsafe configured */
  				if ((_param_rc_fails_thr.get() < _parameters.min[fs_ch] && input_rc.values[fs_ch] < _param_rc_fails_thr.get()) ||
  				    (_param_rc_fails_thr.get() > _parameters.max[fs_ch] && input_rc.values[fs_ch] > _param_rc_fails_thr.get())) {
  					/* failsafe triggered, signal is lost by receiver */
  					signal_lost = true;
  				}
  			}
  		}
  
  		/* read out and scale values from raw message even if signal is invalid */
  		for (unsigned int i = 0; i < channel_count_limited; i++) {
  
  			/*
  			 * 1) Constrain to min/max values, as later processing depends on bounds.
  			 */
  			input_rc.values[i] = math::constrain(input_rc.values[i], _parameters.min[i], _parameters.max[i]);
  
  			/*
  			 * 2) Scale around the mid point differently for lower and upper range.
  			 *
  			 * This is necessary as they don't share the same endpoints and slope.
  			 *
  			 * First normalize to 0..1 range with correct sign (below or above center),
  			 * the total range is 2 (-1..1).
  			 * If center (trim) == min, scale to 0..1, if center (trim) == max,
  			 * scale to -1..0.
  			 *
  			 * As the min and max bounds were enforced in step 1), division by zero
  			 * cannot occur, as for the case of center == min or center == max the if
  			 * statement is mutually exclusive with the arithmetic NaN case.
  			 *
  			 * DO NOT REMOVE OR ALTER STEP 1!
  			 */
  			if (input_rc.values[i] > (_parameters.trim[i] + _parameters.dz[i])) {
  				_rc.channels[i] = (input_rc.values[i] - _parameters.trim[i] - _parameters.dz[i]) / (float)(
  							  _parameters.max[i] - _parameters.trim[i] - _parameters.dz[i]);
  
  			} else if (input_rc.values[i] < (_parameters.trim[i] - _parameters.dz[i])) {
  				_rc.channels[i] = (input_rc.values[i] - _parameters.trim[i] + _parameters.dz[i]) / (float)(
  							  _parameters.trim[i] - _parameters.min[i] - _parameters.dz[i]);
  
  			} else {
  				/* in the configured dead zone, output zero */
  				_rc.channels[i] = 0.f;
  			}
  
  			if (_parameters.rev[i]) {
  				_rc.channels[i] = -_rc.channels[i];
  			}
  
  
  			/* handle any parameter-induced blowups */
  			if (!PX4_ISFINITE(_rc.channels[i])) {
  				_rc.channels[i] = 0.f;
  			}
  		}
  
  		_rc.channel_count = input_rc.channel_count;
  		_rc.rssi = input_rc.rssi;
  		_rc.signal_lost = signal_lost;
  		_rc.timestamp = input_rc.timestamp_last_signal;
  		_rc.frame_drop_count = input_rc.rc_lost_frame_count;
  
  		/* publish rc_channels topic even if signal is invalid, for debug */
  		_rc_channels_pub.publish(_rc);
  
  		// only publish manual control if the signal is present and regularly updating
  		if (input_source_stable && channel_count_stable && !signal_lost) {
  
  			if ((input_rc.timestamp_last_signal > _last_timestamp_signal)
  			    && (input_rc.timestamp_last_signal - _last_timestamp_signal < 1_s)) {
  
  				perf_count(_valid_data_interval_perf);
  
  				// check if channels actually updated
  				bool rc_updated = false;
  
  				for (unsigned i = 0; i < channel_count_limited; i++) {
  					if (_rc_values_previous[i] != input_rc.values[i]) {
  						rc_updated = true;
  						break;
  					}
  				}
  
  				// limit processing if there's no update
  				if (rc_updated || (hrt_elapsed_time(&_last_manual_control_setpoint_publish) > 300_ms)) {
  					UpdateManualSetpoint(input_rc.timestamp_last_signal);
  				}
  
  				UpdateManualSwitches(input_rc.timestamp_last_signal);
  
  				/* Update parameters from RC Channels (tuning with RC) if activated */
  				if (hrt_elapsed_time(&_last_rc_to_param_map_time) > 1_s) {
  					set_params_from_rc();
  					_last_rc_to_param_map_time = hrt_absolute_time();
  				}
  			}
  
  			_last_timestamp_signal = input_rc.timestamp_last_signal;
  		}
  
  		memcpy(_rc_values_previous, input_rc.values, sizeof(input_rc.values[0]) * channel_count_limited);
  		static_assert(sizeof(_rc_values_previous) == sizeof(input_rc.values), "check sizeof(_rc_values_previous)");
  	}
  
  	perf_end(_loop_perf);
  }
  
  switch_pos_t RCUpdate::get_rc_sw3pos_position(uint8_t func, float on_th, float mid_th) const
  {
  	if (_rc.function[func] >= 0) {
  		const bool on_inv = (on_th < 0.f);
  		const bool mid_inv = (mid_th < 0.f);
  
  		const float value = 0.5f * _rc.channels[_rc.function[func]] + 0.5f;
  
  		if (on_inv ? value < on_th : value > on_th) {
  			return manual_control_switches_s::SWITCH_POS_ON;
  
  		} else if (mid_inv ? value < mid_th : value > mid_th) {
  			return manual_control_switches_s::SWITCH_POS_MIDDLE;
  
  		} else {
  			return manual_control_switches_s::SWITCH_POS_OFF;
  		}
  	}
  
  	return manual_control_switches_s::SWITCH_POS_NONE;
  }
  
  switch_pos_t RCUpdate::get_rc_sw2pos_position(uint8_t func, float on_th) const
  {
  	if (_rc.function[func] >= 0) {
  		const bool on_inv = (on_th < 0.f);
  
  		const float value = 0.5f * _rc.channels[_rc.function[func]] + 0.5f;
  
  		if (on_inv ? value < on_th : value > on_th) {
  			return manual_control_switches_s::SWITCH_POS_ON;
  
  		} else {
  			return manual_control_switches_s::SWITCH_POS_OFF;
  		}
  	}
  
  	return manual_control_switches_s::SWITCH_POS_NONE;
  }
  
  void RCUpdate::UpdateManualSwitches(const hrt_abstime &timestamp_sample)
  {
  	manual_control_switches_s switches{};
  	switches.timestamp_sample = timestamp_sample;
  
  	// check mode slot (RC_MAP_FLTMODE) or legacy mode switch (RC_MAP_MODE_SW), but not both
  	if (_param_rc_map_fltmode.get() > 0) {
  		// number of valid slots
  		static constexpr int num_slots = manual_control_switches_s::MODE_SLOT_NUM;
  
  		// the half width of the range of a slot is the total range
  		// divided by the number of slots, again divided by two
  		static constexpr float slot_width_half = 1.f / num_slots;
  
  		// min is -1, max is +1, range is 2. We offset below min and max
  		static constexpr float slot_min = -1.f - 0.05f;
  		static constexpr float slot_max =  1.f + 0.05f;
  
  		// the slot gets mapped by first normalizing into a 0..1 interval using min
  		// and max. Then the right slot is obtained by multiplying with the number of
  		// slots. And finally we add half a slot width to ensure that integer rounding
  		// will take us to the correct final index.
  		const float value = _rc.channels[_param_rc_map_fltmode.get() - 1];
  		switches.mode_slot = (((((value - slot_min) * num_slots) + slot_width_half) / (slot_max - slot_min)) +
  				      slot_width_half) + 1;
  
  		if (switches.mode_slot > num_slots) {
  			switches.mode_slot = num_slots;
  		}
  
  	} else if (_param_rc_map_mode_sw.get() > 0) {
  		switches.mode_switch = get_rc_sw3pos_position(rc_channels_s::FUNCTION_MODE,
  				       _param_rc_auto_th.get(), _param_rc_assist_th.get());
  
  		// only used with legacy mode switch
  		switches.man_switch       = get_rc_sw2pos_position(rc_channels_s::FUNCTION_MAN,       _param_rc_man_th.get());
  		switches.acro_switch      = get_rc_sw2pos_position(rc_channels_s::FUNCTION_ACRO,      _param_rc_acro_th.get());
  		switches.stab_switch      = get_rc_sw2pos_position(rc_channels_s::FUNCTION_STAB,      _param_rc_stab_th.get());
  		switches.posctl_switch    = get_rc_sw2pos_position(rc_channels_s::FUNCTION_POSCTL,    _param_rc_posctl_th.get());
  	}
  
  	switches.return_switch     = get_rc_sw2pos_position(rc_channels_s::FUNCTION_RETURN,     _param_rc_return_th.get());
  	switches.loiter_switch     = get_rc_sw2pos_position(rc_channels_s::FUNCTION_LOITER,     _param_rc_loiter_th.get());
  	switches.offboard_switch   = get_rc_sw2pos_position(rc_channels_s::FUNCTION_OFFBOARD,   _param_rc_offb_th.get());
  	switches.kill_switch       = get_rc_sw2pos_position(rc_channels_s::FUNCTION_KILLSWITCH, _param_rc_killswitch_th.get());
  	switches.arm_switch        = get_rc_sw2pos_position(rc_channels_s::FUNCTION_ARMSWITCH,  _param_rc_armswitch_th.get());
  	switches.transition_switch = get_rc_sw2pos_position(rc_channels_s::FUNCTION_TRANSITION, _param_rc_trans_th.get());
  	switches.gear_switch       = get_rc_sw2pos_position(rc_channels_s::FUNCTION_GEAR,       _param_rc_gear_th.get());
  
  	// last 2 switch updates identical (simple protection from bad RC data)
  	if (switches == _manual_switches_previous) {
  		const bool switches_changed = (switches != _manual_switches_last_publish);
  
  		// publish immediately on change or at ~1 Hz
  		if (switches_changed || (hrt_elapsed_time(&_manual_switches_last_publish.timestamp) >= 1_s)) {
  			uint32_t switch_changes = _manual_switches_last_publish.switch_changes;
  
  			if (switches_changed) {
  				switch_changes++;
  			}
  
  			_manual_switches_last_publish = switches;
  			_manual_switches_last_publish.switch_changes = switch_changes;
  			_manual_switches_last_publish.timestamp_sample = _manual_switches_previous.timestamp_sample;
  			_manual_switches_last_publish.timestamp = hrt_absolute_time();
  			_manual_control_switches_pub.publish(_manual_switches_last_publish);
  		}
  	}
  
  	_manual_switches_previous = switches;
  }
  
  void RCUpdate::UpdateManualSetpoint(const hrt_abstime &timestamp_sample)
  {
  	manual_control_setpoint_s manual_control_setpoint{};
  	manual_control_setpoint.timestamp_sample = timestamp_sample;
  	manual_control_setpoint.data_source = manual_control_setpoint_s::SOURCE_RC;
  
  	// limit controls
  	manual_control_setpoint.y     = get_rc_value(rc_channels_s::FUNCTION_ROLL,    -1.f, 1.f);
  	manual_control_setpoint.x     = get_rc_value(rc_channels_s::FUNCTION_PITCH,   -1.f, 1.f);
  	manual_control_setpoint.r     = get_rc_value(rc_channels_s::FUNCTION_YAW,     -1.f, 1.f);
  	manual_control_setpoint.z     = get_rc_value(rc_channels_s::FUNCTION_THROTTLE, -1.f, 1.f);
  	manual_control_setpoint.flaps = get_rc_value(rc_channels_s::FUNCTION_FLAPS,   -1.f, 1.f);
  	manual_control_setpoint.aux1  = get_rc_value(rc_channels_s::FUNCTION_AUX_1,   -1.f, 1.f);
  	manual_control_setpoint.aux2  = get_rc_value(rc_channels_s::FUNCTION_AUX_2,   -1.f, 1.f);
  	manual_control_setpoint.aux3  = get_rc_value(rc_channels_s::FUNCTION_AUX_3,   -1.f, 1.f);
  	manual_control_setpoint.aux4  = get_rc_value(rc_channels_s::FUNCTION_AUX_4,   -1.f, 1.f);
  	manual_control_setpoint.aux5  = get_rc_value(rc_channels_s::FUNCTION_AUX_5,   -1.f, 1.f);
  	manual_control_setpoint.aux6  = get_rc_value(rc_channels_s::FUNCTION_AUX_6,   -1.f, 1.f);
  
  	// publish manual_control_setpoint topic
  	manual_control_setpoint.timestamp = hrt_absolute_time();
  	_manual_control_setpoint_pub.publish(manual_control_setpoint);
  	_last_manual_control_setpoint_publish = manual_control_setpoint.timestamp;
  
  
  	actuator_controls_s actuator_group_3{};
  	// copy in previous actuator control setpoint in case aux{1, 2, 3} isn't changed
  	_actuator_controls_3_sub.update(&actuator_group_3);
  	// populate and publish actuator_controls_3 copied from mapped manual_control_setpoint
  	actuator_group_3.control[0] = manual_control_setpoint.y;
  	actuator_group_3.control[1] = manual_control_setpoint.x;
  	actuator_group_3.control[2] = manual_control_setpoint.r;
  	actuator_group_3.control[3] = manual_control_setpoint.z;
  	actuator_group_3.control[4] = manual_control_setpoint.flaps;
  
  	float new_aux_values[3];
  	new_aux_values[0] = manual_control_setpoint.aux1;
  	new_aux_values[1] = manual_control_setpoint.aux2;
  	new_aux_values[2] = manual_control_setpoint.aux3;
  
  	// if AUX RC was already active, we update. otherwise, we check
  	// if there is a major stick movement to re-activate RC mode
  	bool major_movement[3] = {false, false, false};
  
  	// detect a big stick movement
  	for (int i = 0; i < 3; i++) {
  		if (fabsf(_last_manual_control_setpoint[i] - new_aux_values[i]) > 0.1f) {
  			major_movement[i] = true;
  		}
  	}
  
  	for (int i = 0; i < 3; i++) {
  		// if someone else (DO_SET_ACTUATOR) updated the actuator control
  		// and we haven't had a major movement, switch back to automatic control
  		if ((fabsf(_last_manual_control_setpoint[i] - actuator_group_3.control[5 + i])
  		     > 0.0001f) && (!major_movement[i])) {
  			_aux_already_active[i] = false;
  		}
  
  		if (_aux_already_active[i] || major_movement[i]) {
  			_aux_already_active[i] = true;
  			_last_manual_control_setpoint[i] = new_aux_values[i];
  
  			actuator_group_3.control[5 + i] = new_aux_values[i];
  		}
  	}
  
  	actuator_group_3.timestamp = hrt_absolute_time();
  	_actuator_group_3_pub.publish(actuator_group_3);
  }
  
  int RCUpdate::task_spawn(int argc, char *argv[])
  {
  	RCUpdate *instance = new RCUpdate();
  
  	if (instance) {
  		_object.store(instance);
  		_task_id = task_id_is_work_queue;
  
  		if (instance->init()) {
  			return PX4_OK;
  		}
  
  	} else {
  		PX4_ERR("alloc failed");
  	}
  
  	delete instance;
  	_object.store(nullptr);
  	_task_id = -1;
  
  	return PX4_ERROR;
  }
  
  int RCUpdate::print_status()
  {
  	PX4_INFO_RAW("Running\n");
  
  	if (_channel_count_max > 0) {
  		PX4_INFO_RAW(" #  MIN  MAX TRIM  DZ REV\n");
  
  		for (int i = 0; i < _channel_count_max; i++) {
  			PX4_INFO_RAW("%2d %4d %4d %4d %3d %3d\n", i, _parameters.min[i], _parameters.max[i], _parameters.trim[i],
  				     _parameters.dz[i], _parameters.rev[i]);
  		}
  	}
  
  	perf_print_counter(_loop_perf);
  	perf_print_counter(_loop_interval_perf);
  	perf_print_counter(_valid_data_interval_perf);
  
  	return 0;
  }
  
  int RCUpdate::custom_command(int argc, char *argv[])
  {
  	return print_usage("unknown command");
  }
  
  int RCUpdate::print_usage(const char *reason)
  {
  	if (reason) {
  		PX4_WARN("%s\n", reason);
  	}
  
  	PRINT_MODULE_DESCRIPTION(
  		R"DESCR_STR(
  ### Description
  The rc_update module handles RC channel mapping: read the raw input channels (`input_rc`),
  then apply the calibration, map the RC channels to the configured channels & mode switches
  and then publish as `rc_channels` and `manual_control_setpoint`.
  
  ### Implementation
  To reduce control latency, the module is scheduled on input_rc publications.
  
  )DESCR_STR");
  
  	PRINT_MODULE_USAGE_NAME("rc_update", "system");
  	PRINT_MODULE_USAGE_COMMAND("start");
  	PRINT_MODULE_USAGE_DEFAULT_COMMANDS();
  
  	return 0;
  }
  
  } // namespace RCUpdate
  
  extern "C" __EXPORT int rc_update_main(int argc, char *argv[])
  {
  	return RCUpdate::RCUpdate::main(argc, argv);
  }
  