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


class EkfInitializationTest : public ::testing::Test {
 public:

	std::shared_ptr<Ekf> _ekf;
	SensorSimulator* _sensor_simulator;

	// Duration of initalization with only providing baro,mag and IMU
	const uint32_t _init_duration_us{2000000};	// 2s

	// Setup the Ekf with synthetic measurements
	void SetUp() override
	{
		_ekf = std::make_shared<Ekf>();
		_ekf->init(0);
		_sensor_simulator = new SensorSimulator(_ekf);

		_sensor_simulator->run(_init_duration_us);
	}

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


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

TEST_F(EkfInitializationTest, 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(EkfInitializationTest, convergesToZero)
{
	// GIVEN: initialized EKF with default IMU, baro and mag input for 2s
	// WHEN: Added more defautl sensor measurements
	_sensor_simulator->run(4000000); // for further 4s

	float converged_pos[3];
	float converged_vel[3];
	float converged_accel_bias[3];
	float converged_gyro_bias[3];
	_ekf->get_position(converged_pos);
	_ekf->get_velocity(converged_vel);
	_ekf->get_accel_bias(converged_accel_bias);
	_ekf->get_gyro_bias(converged_gyro_bias);

	// THEN: EKF should stay or converge to zero
	for(int i=0; i<3; ++i)
	{
		EXPECT_NEAR(0.0f,converged_pos[i],0.001f);
		EXPECT_NEAR(0.0f,converged_vel[i],0.001f);
		EXPECT_NEAR(0.0f,converged_accel_bias[i],0.001f);
		EXPECT_NEAR(0.0f,converged_gyro_bias[i],0.001f);
	}
}

TEST_F(EkfInitializationTest, gpsFusion)
{
	// GIVEN: initialized EKF with default IMU, baro and mag input for 2s
	// WHEN: setting GPS measurements for 11s, minimum GPS health time is set to 10 sec

	_sensor_simulator->startGps();
	_sensor_simulator->run(11000000); // for further 3s

	// 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(EkfInitializationTest, 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 = {0.0f,0.0f,0.1f};

	_sensor_simulator->startGps();
	_sensor_simulator->setImuBias(accel_bias, Vector3f{0.0f,0.0f,0.0f});
	_sensor_simulator->run(10000000);

	float converged_pos[3];
	float converged_vel[3];
	float converged_accel_bias[3];
	float converged_gyro_bias[3];
	_ekf->get_position(converged_pos);
	_ekf->get_velocity(converged_vel);
	_ekf->get_accel_bias(converged_accel_bias);
	_ekf->get_gyro_bias(converged_gyro_bias);

	// THEN: EKF should estimate bias correctelly
	for(int i=0; i<3; ++i)
	{
		EXPECT_NEAR(0.0f,converged_pos[i],0.001f) << "i: " << i;
		EXPECT_NEAR(0.0f,converged_vel[i],0.001f) << "i: " << i;
		EXPECT_NEAR(accel_bias(i),converged_accel_bias[i],0.001f) << "i: " << i;
		EXPECT_NEAR(0.0f,converged_gyro_bias[i],0.001f) << "i: " << i;
	}
}

// TODO: Add sampling tests