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#include "ManualControlSelector.hpp"

void ManualControlSelector::updateValidityOfChosenInput(uint64_t now)
{
	if (!isInputValid(_setpoint, now)) {
		_setpoint.valid = false;
		_instance = -1;
	}
}

void ManualControlSelector::updateWithNewInputSample(uint64_t now, const manual_control_setpoint_s &input, int instance)
{
	// First check if the chosen input got invalid, so it can get replaced
	updateValidityOfChosenInput(now);

	const bool update_existing_input = _setpoint.valid && (input.data_source == _setpoint.data_source);
	const bool start_using_new_input = !_setpoint.valid;

	// Switch to new input if it's valid and we don't already have a valid one
	if (isInputValid(input, now) && (update_existing_input || start_using_new_input)) {
		_setpoint = input;
		_setpoint.valid = true;
		_setpoint.timestamp = now; // timestamp_sample is preserved
		_instance = instance;

		if (_first_valid_source == manual_control_setpoint_s::SOURCE_UNKNOWN) {
			// initialize first valid source once
			_first_valid_source = _setpoint.data_source;
		}
	}
}

bool ManualControlSelector::isInputValid(const manual_control_setpoint_s &input, uint64_t now) const
{
	// Check for timeout
	const bool sample_from_the_past = now >= input.timestamp_sample;
	const bool sample_newer_than_timeout = now - input.timestamp_sample < _timeout;

	// Check if source matches the configuration
	const bool source_rc_matched = (_rc_in_mode == 0) && (input.data_source == manual_control_setpoint_s::SOURCE_RC);
	const bool source_mavlink_matched = (_rc_in_mode == 1) &&
					    (input.data_source == manual_control_setpoint_s::SOURCE_MAVLINK_0
					     || input.data_source == manual_control_setpoint_s::SOURCE_MAVLINK_1
					     || input.data_source == manual_control_setpoint_s::SOURCE_MAVLINK_2
					     || input.data_source == manual_control_setpoint_s::SOURCE_MAVLINK_3
					     || input.data_source == manual_control_setpoint_s::SOURCE_MAVLINK_4
					     || input.data_source == manual_control_setpoint_s::SOURCE_MAVLINK_5);
	const bool source_any_matched = (_rc_in_mode == 2);
	const bool source_first_matched = (_rc_in_mode == 3) &&
					  (input.data_source == _first_valid_source
					   || _first_valid_source == manual_control_setpoint_s::SOURCE_UNKNOWN);

	return sample_from_the_past && sample_newer_than_timeout && input.valid
	       && (source_rc_matched || source_mavlink_matched || source_any_matched || source_first_matched);
}

manual_control_setpoint_s &ManualControlSelector::setpoint()
{
	return _setpoint;
}