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/*  test_interpolator.h                                                  */
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#ifndef TEST_INTERPOLATOR_H
#define TEST_INTERPOLATOR_H

#include "modules/network_synchronizer/interpolator.h"

#include "tests/test_macros.h"

namespace TestInterpolator {

template <class T>
T generate_value(real_t value) {
	if constexpr (std::is_same_v<T, Vector2> || std::is_same_v<T, Vector2i>) {
		return T(value, value);
	} else if constexpr (std::is_same_v<T, Vector3> || std::is_same_v<T, Vector3i>) {
		return T(value, value, value);
	} else {
		return static_cast<T>(value);
	}
}

// TODO: Add other types
TEST_CASE_TEMPLATE("[Modules][Interpolator] Interpolation", T, int, real_t, Vector2, Vector2i, Vector3) {
	LocalVector<real_t> fractions;
	fractions.reserve(7);
	fractions.push_back(0.0);
	fractions.push_back(1.0);
	fractions.push_back(0.5);
	fractions.push_back(0.001);
	fractions.push_back(0.999);
	fractions.push_back(0.25);
	fractions.push_back(0.75);

	RBMap<real_t, real_t> values;
	values.insert(0.0, 1.0);
	values.insert(-1.0, 1.0);
	values.insert(0.0, -1.0);
	values.insert(10, 15);

	Interpolator interpolator;
	for (const RBMap<real_t, real_t>::Element *E = values.front(); E; E = E->next()) {
		for (uint32_t j = 0; j < fractions.size(); ++j) {
			// Skip custom interpolator for now
			for (int k = Interpolator::FALLBACK_INTERPOLATE; k < Interpolator::FALLBACK_CUSTOM_INTERPOLATOR; ++k) {
				const T first_value = generate_value<T>(E->key());
				const T second_value = generate_value<T>(E->value());

				interpolator.reset();
				const int variable_id = interpolator.register_variable(T(), static_cast<Interpolator::Fallback>(k));
				interpolator.terminate_init();
				interpolator.begin_write(0);
				interpolator.epoch_insert(variable_id, first_value);
				interpolator.end_write();

				interpolator.begin_write(1);
				interpolator.epoch_insert(variable_id, second_value);
				interpolator.end_write();

				CAPTURE(k);
				CAPTURE(fractions[j]);
				CAPTURE(first_value);
				CAPTURE(second_value);
				const T result = interpolator.pop_epoch(0, fractions[j])[0];
				switch (k) {
					case Interpolator::FALLBACK_INTERPOLATE: {
						CHECK(result == Interpolator::interpolate(first_value, second_value, fractions[j]).operator T());
					} break;
					case Interpolator::FALLBACK_DEFAULT: {
						if (fractions[j] == 0.0) {
							CHECK(result == first_value);
						} else if (fractions[j] == 1.0) {
							CHECK(result == second_value);
						} else {
							CHECK(result == T());
						}
					} break;
					case Interpolator::FALLBACK_OLD_OR_NEAREST: {
						if (fractions[j] == 0.0) {
							CHECK(result == first_value);
						} else if (fractions[j] == 1.0) {
							CHECK(result == second_value);
						} else {
							CHECK(result == first_value);
						}
					} break;
					case Interpolator::FALLBACK_NEW_OR_NEAREST: {
						if (fractions[j] == 0.0) {
							CHECK(result == first_value);
						} else if (fractions[j] == 1.0) {
							CHECK(result == second_value);
						} else {
							CHECK(result == second_value);
						}
					} break;
				}
			}
		}
	}
}
} // namespace TestInterpolator

#endif // TEST_INTERPOLATOR_H