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/**
 * Test code for the Heading Smoothing library
 * Run exclusively this test with the command "make tests TESTFILTER=HeadingSmoothing"
 */

#include "mathlib/math/Limits.hpp"
#include <gtest/gtest.h>

#include <motion_planning/HeadingSmoothing.hpp>

using namespace matrix;

class HeadingSmoothingTest : public ::testing::Test
{
public:
	HeadingSmoothingTest()
	{
		_smoothing.setMaxHeadingRate(15.f);
		_smoothing.setMaxHeadingAccel(1.f);
	}

	HeadingSmoothing _smoothing;
	float _dt{.1f};
};

TEST_F(HeadingSmoothingTest, convergence)
{
	const float heading_current = math::radians(0.f);
	const float heading_target = math::radians(5.f);
	_smoothing.reset(heading_current, 0.f);

	const int nb_steps = ceilf(1.f / _dt);

	for (int i = 0; i < nb_steps; i++) {
		_smoothing.update(heading_target, _dt);
	}

	const float heading = _smoothing.getSmoothedHeading();
	const float heading_rate = _smoothing.getSmoothedHeadingRate();
	EXPECT_EQ(heading, heading_target) << "heading (deg): " << math::degrees(heading);
	EXPECT_EQ(heading_rate, 0.f);
}

TEST_F(HeadingSmoothingTest, zero_crossing)
{
	const float heading_current = math::radians(-95.f);
	const float heading_target = math::radians(5.f);
	_smoothing.reset(heading_current, 0.f);

	const int nb_steps = ceilf(4.f / _dt);

	for (int i = 0; i < nb_steps; i++) {
		_smoothing.update(heading_target, _dt);
	}

	const float heading = _smoothing.getSmoothedHeading();
	const float heading_rate = _smoothing.getSmoothedHeadingRate();
	EXPECT_EQ(heading, heading_target) << "heading (deg): " << math::degrees(heading);
	EXPECT_EQ(heading_rate, 0.f);
}

TEST_F(HeadingSmoothingTest, wrap_pi)
{
	const float heading_current = math::radians(-170.f);
	const float heading_target = math::radians(170.f);
	_smoothing.reset(heading_current, 0.f);

	const int nb_steps = ceilf(2.f / _dt);

	for (int i = 0; i < nb_steps; i++) {
		_smoothing.update(heading_target, _dt);
	}

	const float heading = _smoothing.getSmoothedHeading();
	const float heading_rate = _smoothing.getSmoothedHeadingRate();
	EXPECT_EQ(heading, heading_target) << "heading (deg): " << math::degrees(heading);
	EXPECT_EQ(heading_rate, 0.f);
}

TEST_F(HeadingSmoothingTest, positive_rate)
{
	const float max_heading_rate = .15f;
	_smoothing.setMaxHeadingRate(max_heading_rate);
	const float heading_current = math::radians(-170.f);
	const float heading_target = math::radians(-20.f);
	_smoothing.reset(heading_current, 0.f);

	const int nb_steps = ceilf(2.f / _dt);

	for (int i = 0; i < nb_steps; i++) {
		_smoothing.update(heading_target, _dt);
	}

	const float heading_rate = _smoothing.getSmoothedHeadingRate();
	EXPECT_EQ(heading_rate, max_heading_rate);
}

TEST_F(HeadingSmoothingTest, negative_rate)
{
	const float max_heading_rate = 0.15;
	_smoothing.setMaxHeadingRate(max_heading_rate);
	const float heading_current = math::radians(-20.f);
	const float heading_target = math::radians(-140.f);
	_smoothing.reset(heading_current, 0.f);

	const int nb_steps = ceilf(2.f / _dt);

	for (int i = 0; i < nb_steps; i++) {
		_smoothing.update(heading_target, _dt);
	}

	const float heading_rate = _smoothing.getSmoothedHeadingRate();
	EXPECT_EQ(heading_rate, -max_heading_rate);
}