/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * Copyright (C) 2026, Ideas on Board
 *
 * Dual Type and Quantizer tests
 */

#include "../src/ipa/libipa/quantized.h"

#include <algorithm>
#include <cmath>
#include <iostream>
#include <stdint.h>

#include "test.h"

using namespace std;
using namespace libcamera;
using namespace ipa;

struct BrightnessHueTraits {
	using QuantizedType = uint8_t;
	static QuantizedType fromFloat(float v)
	{
		int quantized = std::lround(v * 128.0f);
		return std::clamp<int>(quantized, -128, 127);
	}
	static constexpr float toFloat(QuantizedType v)
	{
		return static_cast<float>(v) / 128.0f;
	}
};

using BrightnessHueQuantizer = Quantized<BrightnessHueTraits>;

struct ContrastSaturationTraits {
	using QuantizedType = uint8_t;
	static QuantizedType fromFloat(float v)
	{
		int quantized = std::lround(v * 128.0f);
		return std::clamp<int>(quantized, 0, 255);
	}
	static constexpr float toFloat(QuantizedType v)
	{
		return static_cast<float>(v) / 128.0f;
	}
};

using ContrastSaturationQuantizer = Quantized<ContrastSaturationTraits>;

using BrightnessQ = BrightnessHueQuantizer;
using HueQ = BrightnessHueQuantizer;
using ContrastQ = ContrastSaturationQuantizer;
using SaturationQ = ContrastSaturationQuantizer;

class QuantizedTest : public Test
{
protected:
	int run()
	{
		/* Test construction from float */
		{
			BrightnessQ b(0.5f);
			if (b.quantized() != 64 || std::abs(b.value() - 0.5f) > 0.01f)
				return TestFail;
		}

		/* Test construction from T */
		{
			ContrastQ c(uint8_t(128));
			if (c.quantized() != 128 || std::abs(c.value() - 1.0f) > 0.01f)
				return TestFail;
		}

		/*
		 * Only construction from the exact storage type or a float
		 * is permitted.
		 */
		static_assert(!std::is_constructible_v<BrightnessQ, unsigned int>);
		static_assert(!std::is_constructible_v<BrightnessQ, int8_t>);
		static_assert(!std::is_constructible_v<BrightnessQ, double>);
		static_assert(!std::is_constructible_v<ContrastQ, int>);
		static_assert(!std::is_constructible_v<ContrastQ, int8_t>);
		static_assert(!std::is_constructible_v<ContrastQ, unsigned int>);

		/* Test equality */
		{
			BrightnessQ b1(0.5f), b2(uint8_t(64));
			if (!(b1 == b2))
				return TestFail;
		}

		/* Test inequality */
		{
			BrightnessQ b1(0.5f), b2(-0.5f);
			if (!(b1 != b2))
				return TestFail;
		}

		/* Test copying */
		{
			BrightnessQ b1(0.25f);
			BrightnessQ b2 = b1;
			if (!(b1 == b2))
				return TestFail;
		}

		/* Test assignment */
		{
			ContrastQ c1(1.5f);
			ContrastQ c2(0.0f);
			c2 = c1;
			if (!(c1 == c2))
				return TestFail;
		}

		/*
		 * Test construction from different floats mapping to same
		 * quantized value
		 */
		{
			/* Two floats that have the same quantized value. */
			const float f1 = 1.007f;
			const float f2 = 1.008f;

			ContrastQ c1(f1);
			ContrastQ c2(f2);

			/* Quantized values must match */
			if (!(c1.quantized() == c2.quantized()))
				return TestFail;

			/* Float values must now match */
			if (!(c1.value() == c2.value()))
				return TestFail;

			if (!(c1 == c2))
				return TestFail;
		}

		/* Test constexpr operation */
		{
			constexpr BrightnessQ b1(uint8_t(1));
			constexpr BrightnessQ b2(uint8_t(2));

			static_assert(b1.quantized() == 1);
			static_assert(b2.quantized() == 2);
			static_assert(b1 != b2);
			static_assert(!(b1 == b2));
		}

		return TestPass;
	}
};

TEST_REGISTER(QuantizedTest)