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#include <gtest/gtest.h>
#include <math.h>
#include <memory>
#include "EKF/ekf.h"
#include "sensor_simulator/sensor_simulator.h"
#include "sensor_simulator/ekf_wrapper.h"

class EkfBasicsTest : public ::testing::Test {
 public:
	EkfBasicsTest(): ::testing::Test(),
	_ekf{std::make_shared<Ekf>()},
	_sensor_simulator(_ekf),
	_ekf_wrapper(_ekf) {};

	std::shared_ptr<Ekf> _ekf;
	SensorSimulator _sensor_simulator;
	EkfWrapper _ekf_wrapper;


	// Duration of initalization with only providing baro,mag and IMU
	const uint32_t _init_duration_s{2};

	// Setup the Ekf with synthetic measurements
	void SetUp() override
	{
		_ekf->init(0);
		_sensor_simulator.runSeconds(_init_duration_s);
	}

	// Use this method to clean up any memory, network etc. after each test
	void TearDown() override
	{
	}
};


TEST_F(EkfBasicsTest, tiltAlign)
{
	// GIVEN: reasonable static sensor data for some duration
	// THEN: EKF should tilt align
	EXPECT_TRUE(_ekf->attitude_valid());
}

TEST_F(EkfBasicsTest, initialControlMode)
{
	// GIVEN: reasonable static sensor data for some duration
	// THEN: EKF control status should be reasonable
	filter_control_status_u control_status;
	_ekf->get_control_mode(&control_status.value);

	EXPECT_EQ(1, (int) control_status.flags.tilt_align);
	EXPECT_EQ(1, (int) control_status.flags.yaw_align);
	EXPECT_EQ(0, (int) control_status.flags.gps);
	EXPECT_EQ(0, (int) control_status.flags.opt_flow);
	EXPECT_EQ(1, (int) control_status.flags.mag_hdg);
	EXPECT_EQ(0, (int) control_status.flags.mag_3D);
	EXPECT_EQ(0, (int) control_status.flags.mag_dec);
	EXPECT_EQ(0, (int) control_status.flags.in_air);
	EXPECT_EQ(0, (int) control_status.flags.wind);
	EXPECT_EQ(1, (int) control_status.flags.baro_hgt);
	EXPECT_EQ(0, (int) control_status.flags.rng_hgt);
	EXPECT_EQ(0, (int) control_status.flags.gps_hgt);
	EXPECT_EQ(0, (int) control_status.flags.ev_pos);
	EXPECT_EQ(0, (int) control_status.flags.ev_yaw);
	EXPECT_EQ(0, (int) control_status.flags.ev_hgt);
	EXPECT_EQ(0, (int) control_status.flags.fuse_beta);
	EXPECT_EQ(0, (int) control_status.flags.mag_field_disturbed);
	EXPECT_EQ(0, (int) control_status.flags.fixed_wing);
	EXPECT_EQ(0, (int) control_status.flags.mag_fault);
	EXPECT_EQ(0, (int) control_status.flags.gnd_effect);
	EXPECT_EQ(0, (int) control_status.flags.rng_stuck);
	EXPECT_EQ(0, (int) control_status.flags.gps_yaw);
	EXPECT_EQ(0, (int) control_status.flags.mag_aligned_in_flight);
	EXPECT_EQ(0, (int) control_status.flags.ev_vel);
	EXPECT_EQ(0, (int) control_status.flags.synthetic_mag_z);
}

TEST_F(EkfBasicsTest, convergesToZero)
{
	// GIVEN: initialized EKF with default IMU, baro and mag input
	_sensor_simulator.runSeconds(4);

	Vector3f pos = _ekf_wrapper.getPosition();
	Vector3f vel = _ekf_wrapper.getVelocity();
	Vector3f accel_bias = _ekf_wrapper.getAccelBias();
	Vector3f gyro_bias = _ekf_wrapper.getGyroBias();
	Vector3f ref{0.0f, 0.0f, 0.0f};

	// THEN: EKF should stay or converge to zero
	EXPECT_TRUE(matrix::isEqual(pos, ref, 0.001f));
	EXPECT_TRUE(matrix::isEqual(vel, ref, 0.001f));
	EXPECT_TRUE(matrix::isEqual(accel_bias, ref, 0.001f));
	EXPECT_TRUE(matrix::isEqual(gyro_bias, ref, 0.001f));
}

TEST_F(EkfBasicsTest, gpsFusion)
{
	// GIVEN: initialized EKF with default IMU, baro and mag input for
	// WHEN: setting GPS measurements for 11s, minimum GPS health time is set to 10 sec

	_sensor_simulator.startGps();
	_sensor_simulator.runSeconds(11);

	// THEN: EKF should fuse GPS, but no other position sensor
	filter_control_status_u control_status;
	_ekf->get_control_mode(&control_status.value);
	EXPECT_EQ(1, (int) control_status.flags.tilt_align);
	EXPECT_EQ(1, (int) control_status.flags.yaw_align);
	EXPECT_EQ(1, (int) control_status.flags.gps);
	EXPECT_EQ(0, (int) control_status.flags.opt_flow);
	EXPECT_EQ(1, (int) control_status.flags.mag_hdg);
	EXPECT_EQ(0, (int) control_status.flags.mag_3D);
	EXPECT_EQ(0, (int) control_status.flags.mag_dec);
	EXPECT_EQ(0, (int) control_status.flags.in_air);
	EXPECT_EQ(0, (int) control_status.flags.wind);
	EXPECT_EQ(1, (int) control_status.flags.baro_hgt);
	EXPECT_EQ(0, (int) control_status.flags.rng_hgt);
	EXPECT_EQ(0, (int) control_status.flags.gps_hgt);
	EXPECT_EQ(0, (int) control_status.flags.ev_pos);
	EXPECT_EQ(0, (int) control_status.flags.ev_yaw);
	EXPECT_EQ(0, (int) control_status.flags.ev_hgt);
	EXPECT_EQ(0, (int) control_status.flags.fuse_beta);
	EXPECT_EQ(0, (int) control_status.flags.mag_field_disturbed);
	EXPECT_EQ(0, (int) control_status.flags.fixed_wing);
	EXPECT_EQ(0, (int) control_status.flags.mag_fault);
	EXPECT_EQ(0, (int) control_status.flags.gnd_effect);
	EXPECT_EQ(0, (int) control_status.flags.rng_stuck);
	EXPECT_EQ(0, (int) control_status.flags.gps_yaw);
	EXPECT_EQ(0, (int) control_status.flags.mag_aligned_in_flight);
	EXPECT_EQ(0, (int) control_status.flags.ev_vel);
	EXPECT_EQ(0, (int) control_status.flags.synthetic_mag_z);
}

TEST_F(EkfBasicsTest, accleBiasEstimation)
{
	// GIVEN: initialized EKF with default IMU, baro and mag input for 2s
	// WHEN: Added more sensor measurements with accel bias and gps measurements
	Vector3f accel_bias_sim = {0.0f,0.0f,0.1f};

	_sensor_simulator.startGps();
	_sensor_simulator.setImuBias(accel_bias_sim, Vector3f{0.0f,0.0f,0.0f});
	_sensor_simulator.runSeconds(10);

	Vector3f pos = _ekf_wrapper.getPosition();
	Vector3f vel = _ekf_wrapper.getVelocity();
	Vector3f accel_bias = _ekf_wrapper.getAccelBias();
	Vector3f gyro_bias = _ekf_wrapper.getGyroBias();
	Vector3f zero{0.0f, 0.0f, 0.0f};

	// THEN: EKF should stay or converge to zero
	EXPECT_TRUE(matrix::isEqual(pos, zero, 0.001f));
	EXPECT_TRUE(matrix::isEqual(vel, zero, 0.001f));
	EXPECT_TRUE(matrix::isEqual(accel_bias, accel_bias_sim, 0.001f));
	EXPECT_TRUE(matrix::isEqual(gyro_bias, zero, 0.001f));
}

// TODO: Add sampling tests