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/**
 * @file ev_control.cpp
 * Control functions for ekf external vision control
 */

#include "ekf.h"

void Ekf::controlExternalVisionFusion()
{
	_ev_pos_b_est.predict(_dt_ekf_avg);

	// Check for new external vision data
	extVisionSample ev_sample;

	if (_ext_vision_buffer && _ext_vision_buffer->pop_first_older_than(_time_delayed_us, &ev_sample)) {

		bool ev_reset = (ev_sample.reset_counter != _ev_sample_prev.reset_counter);

		// determine if we should use the horizontal position observations
		bool quality_sufficient = (_params.ev_quality_minimum <= 0) || (ev_sample.quality >= _params.ev_quality_minimum);

		const bool starting_conditions_passing = quality_sufficient
				&& ((ev_sample.time_us - _ev_sample_prev.time_us) < EV_MAX_INTERVAL)
				&& ((_params.ev_quality_minimum <= 0) || (_ev_sample_prev.quality >= _params.ev_quality_minimum)) // previous quality sufficient
				&& ((_params.ev_quality_minimum <= 0) || (_ext_vision_buffer->get_newest().quality >= _params.ev_quality_minimum)) // newest quality sufficient
				&& isNewestSampleRecent(_time_last_ext_vision_buffer_push, EV_MAX_INTERVAL);

		updateEvAttitudeErrorFilter(ev_sample, ev_reset);
		controlEvYawFusion(ev_sample, starting_conditions_passing, ev_reset, quality_sufficient, _aid_src_ev_yaw);
		controlEvVelFusion(ev_sample, starting_conditions_passing, ev_reset, quality_sufficient, _aid_src_ev_vel);
		controlEvPosFusion(ev_sample, starting_conditions_passing, ev_reset, quality_sufficient, _aid_src_ev_pos);
		controlEvHeightFusion(ev_sample, starting_conditions_passing, ev_reset, quality_sufficient, _aid_src_ev_hgt);

		if (quality_sufficient) {
			_ev_sample_prev = ev_sample;
		}

		// record corresponding yaw state for future EV delta heading innovation (logging only)
		_ev_yaw_pred_prev = getEulerYaw(_state.quat_nominal);

	} else if ((_control_status.flags.ev_pos || _control_status.flags.ev_vel || _control_status.flags.ev_yaw
		    || _control_status.flags.ev_hgt)
		   && isTimedOut(_ev_sample_prev.time_us, 2 * EV_MAX_INTERVAL)) {

		// Turn off EV fusion mode if no data has been received
		stopEvPosFusion();
		stopEvVelFusion();
		stopEvYawFusion();
		stopEvHgtFusion();

		_ev_q_error_initialized = false;

		_warning_events.flags.vision_data_stopped = true;
		ECL_WARN("vision data stopped");
	}
}

void Ekf::updateEvAttitudeErrorFilter(extVisionSample &ev_sample, bool ev_reset)
{
	const Quatf q_error((_state.quat_nominal * ev_sample.quat.inversed()).normalized());

	if (!q_error.isAllFinite()) {
		return;
	}

	if (!_ev_q_error_initialized || ev_reset) {
		_ev_q_error_filt.reset(q_error);
		_ev_q_error_initialized = true;

	} else {
		_ev_q_error_filt.update(q_error);
	}
}