// SPDX-License-Identifier: GPL-2.0+

#include <kunit/test.h>

#include <drm/drm_fixed.h>
#include <drm/drm_fourcc.h>

#include "../../drm_crtc_internal.h"

#include "../vkms_formats.h"

#define TEST_BUFF_SIZE 50

MODULE_IMPORT_NS("EXPORTED_FOR_KUNIT_TESTING");

/**
 * struct pixel_yuv_u16 - Internal representation of a pixel color.
 * @y: Luma value, stored in 16 bits, without padding, using
 *     machine endianness
 * @u: Blue difference chroma value, stored in 16 bits, without padding, using
 *     machine endianness
 * @v: Red difference chroma value, stored in 16 bits, without padding, using
 *     machine endianness
 */
struct pixel_yuv_u16 {
        u16 y, u, v;
};

/*
 * struct yuv_u16_to_argb_u16_case - Reference values to test the color
 * conversions in VKMS between YUV to ARGB
 *
 * @encoding: Encoding used to convert RGB to YUV
 * @range: Range used to convert RGB to YUV
 * @n_colors: Count of test colors in this case
 * @format_pair.name: Name used for this color conversion, used to
 *                    clarify the test results
 * @format_pair.rgb: RGB color tested
 * @format_pair.yuv: Same color as @format_pair.rgb, but converted to
 *                   YUV using @encoding and @range.
 */
struct yuv_u16_to_argb_u16_case {
        enum drm_color_encoding encoding;
        enum drm_color_range range;
        size_t n_colors;
        struct format_pair {
                char *name;
                struct pixel_yuv_u16 yuv;
                struct pixel_argb_u16 argb;
        } colors[TEST_BUFF_SIZE];
};

/*
 * The YUV color representation were acquired via the colour python framework.
 * Below are the function calls used for generating each case.
 *
 * For more information got to the docs:
 * https://colour.readthedocs.io/en/master/generated/colour.RGB_to_YCbCr.html
 */
static struct yuv_u16_to_argb_u16_case yuv_u16_to_argb_u16_cases[] = {
        /*
         * colour.RGB_to_YCbCr(<rgb color in 16 bit form>,
         *                     K=colour.WEIGHTS_YCBCR["ITU-R BT.601"],
         *                     in_bits = 16,
         *                     in_legal = False,
         *                     in_int = True,
         *                     out_bits = 16,
         *                     out_legal = False,
         *                     out_int = True)
         *
         * Tests cases for color conversion generated by converting RGB
         * values to YUV BT601 full range using the ITU-R BT.601 weights.
         */
        {
                .encoding = DRM_COLOR_YCBCR_BT601,
                .range = DRM_COLOR_YCBCR_FULL_RANGE,
                .n_colors = 6,
                .colors = {
                        { "white", { 0xffff, 0x8000, 0x8000 }, { 0xffff, 0xffff, 0xffff, 0xffff }},
                        { "gray",  { 0x8080, 0x8000, 0x8000 }, { 0xffff, 0x8080, 0x8080, 0x8080 }},
                        { "black", { 0x0000, 0x8000, 0x8000 }, { 0xffff, 0x0000, 0x0000, 0x0000 }},
                        { "red",   { 0x4c8b, 0x54ce, 0xffff }, { 0xffff, 0xffff, 0x0000, 0x0000 }},
                        { "green", { 0x9645, 0x2b33, 0x14d1 }, { 0xffff, 0x0000, 0xffff, 0x0000 }},
                        { "blue",  { 0x1d2f, 0xffff, 0x6b2f }, { 0xffff, 0x0000, 0x0000, 0xffff }},
                }
        },
        /*
         * colour.RGB_to_YCbCr(<rgb color in 16 bit form>,
         *                     K=colour.WEIGHTS_YCBCR["ITU-R BT.601"],
         *                     in_bits = 16,
         *                     in_legal = False,
         *                     in_int = True,
         *                     out_bits = 16,
         *                     out_legal = True,
         *                     out_int = True)
         * Tests cases for color conversion generated by converting RGB
         * values to YUV BT601 limited range using the ITU-R BT.601 weights.
         */
        {
                .encoding = DRM_COLOR_YCBCR_BT601,
                .range = DRM_COLOR_YCBCR_LIMITED_RANGE,
                .n_colors = 6,
                .colors = {
                        { "white", { 0xeb00, 0x8000, 0x8000 }, { 0xffff, 0xffff, 0xffff, 0xffff }},
                        { "gray",  { 0x7dee, 0x8000, 0x8000 }, { 0xffff, 0x8080, 0x8080, 0x8080 }},
                        { "black", { 0x1000, 0x8000, 0x8000 }, { 0xffff, 0x0000, 0x0000, 0x0000 }},
                        { "red",   { 0x517b, 0x5a34, 0xf000 }, { 0xffff, 0xffff, 0x0000, 0x0000 }},
                        { "green", { 0x908e, 0x35cc, 0x2237 }, { 0xffff, 0x0000, 0xffff, 0x0000 }},
                        { "blue",  { 0x28f7, 0xf000, 0x6dc9 }, { 0xffff, 0x0000, 0x0000, 0xffff }},
                }
        },
        /*
         * colour.RGB_to_YCbCr(<rgb color in 16 bit form>,
         *                     K=colour.WEIGHTS_YCBCR["ITU-R BT.709"],
         *                     in_bits = 16,
         *                     in_legal = False,
         *                     in_int = True,
         *                     out_bits = 16,
         *                     out_legal = False,
         *                     out_int = True)
         * Tests cases for color conversion generated by converting RGB
         * values to YUV BT709 full range using the ITU-R BT.709 weights.
         */
        {
                .encoding = DRM_COLOR_YCBCR_BT709,
                .range = DRM_COLOR_YCBCR_FULL_RANGE,
                .n_colors = 6,
                .colors = {
                        { "white", { 0xffff, 0x8000, 0x8000 }, { 0xffff, 0xffff, 0xffff, 0xffff }},
                        { "gray",  { 0x8080, 0x8000, 0x8000 }, { 0xffff, 0x8080, 0x8080, 0x8080 }},
                        { "black", { 0x0000, 0x8000, 0x8000 }, { 0xffff, 0x0000, 0x0000, 0x0000 }},
                        { "red",   { 0x366d, 0x62ac, 0xffff }, { 0xffff, 0xffff, 0x0000, 0x0000 }},
                        { "green", { 0xb717, 0x1d55, 0x0bbd }, { 0xffff, 0x0000, 0xffff, 0x0000 }},
                        { "blue",  { 0x127c, 0xffff, 0x7443 }, { 0xffff, 0x0000, 0x0000, 0xffff }},
                }
        },
        /*
         * colour.RGB_to_YCbCr(<rgb color in 16 bit form>,
         *                     K=colour.WEIGHTS_YCBCR["ITU-R BT.709"],
         *                     in_bits = 16,
         *                     in_legal = False,
         *                     in_int = True,
         *                     out_bits = 16,
         *                     out_legal = True,
         *                     out_int = True)
         * Tests cases for color conversion generated by converting RGB
         * values to YUV BT709 limited range using the ITU-R BT.709 weights.
         */
        {
                .encoding = DRM_COLOR_YCBCR_BT709,
                .range = DRM_COLOR_YCBCR_LIMITED_RANGE,
                .n_colors = 6,
                .colors = {
                        { "white", { 0xeb00, 0x8000, 0x8000 }, { 0xffff, 0xffff, 0xffff, 0xffff }},
                        { "gray",  { 0x7dee, 0x8000, 0x8000 }, { 0xffff, 0x8080, 0x8080, 0x8080 }},
                        { "black", { 0x1000, 0x8000, 0x8000 }, { 0xffff, 0x0000, 0x0000, 0x0000 }},
                        { "red",   { 0x3e8f, 0x6656, 0xf000 }, { 0xffff, 0xffff, 0x0000, 0x0000 }},
                        { "green", { 0xaca1, 0x29aa, 0x1a45 }, { 0xffff, 0x0000, 0xffff, 0x0000 }},
                        { "blue",  { 0x1fd0, 0xf000, 0x75bb }, { 0xffff, 0x0000, 0x0000, 0xffff }},
                }
        },
        /*
         * colour.RGB_to_YCbCr(<rgb color in 16 bit form>,
         *                     K=colour.WEIGHTS_YCBCR["ITU-R BT.2020"],
         *                     in_bits = 16,
         *                     in_legal = False,
         *                     in_int = True,
         *                     out_bits = 16,
         *                     out_legal = False,
         *                     out_int = True)
         * Tests cases for color conversion generated by converting RGB
         * values to YUV BT2020 full range using the ITU-R BT.2020 weights.
         */
        {
                .encoding = DRM_COLOR_YCBCR_BT2020,
                .range = DRM_COLOR_YCBCR_FULL_RANGE,
                .n_colors = 6,
                .colors = {
                        { "white", { 0xffff, 0x8000, 0x8000 }, { 0xffff, 0xffff, 0xffff, 0xffff }},
                        { "gray",  { 0x8080, 0x8000, 0x8000 }, { 0xffff, 0x8080, 0x8080, 0x8080 }},
                        { "black", { 0x0000, 0x8000, 0x8000 }, { 0xffff, 0x0000, 0x0000, 0x0000 }},
                        { "red",   { 0x4340, 0x5c41, 0xffff }, { 0xffff, 0xffff, 0x0000, 0x0000 }},
                        { "green", { 0xad91, 0x23bf, 0x0a4c }, { 0xffff, 0x0000, 0xffff, 0x0000 }},
                        { "blue",  { 0x0f2e, 0xffff, 0x75b5 }, { 0xffff, 0x0000, 0x0000, 0xffff }},
                }
        },
        /*
         * colour.RGB_to_YCbCr(<rgb color in 16 bit form>,
         *                     K=colour.WEIGHTS_YCBCR["ITU-R BT.2020"],
         *                     in_bits = 16,
         *                     in_legal = False,
         *                     in_int = True,
         *                     out_bits = 16,
         *                     out_legal = True,
         *                     out_int = True)
         * Tests cases for color conversion generated by converting RGB
         * values to YUV BT2020 limited range using the ITU-R BT.2020 weights.
         */
        {
                .encoding = DRM_COLOR_YCBCR_BT2020,
                .range = DRM_COLOR_YCBCR_LIMITED_RANGE,
                .n_colors = 6,
                .colors = {
                        { "white", { 0xeb00, 0x8000, 0x8000 }, { 0xffff, 0xffff, 0xffff, 0xffff }},
                        { "gray",  { 0x7dee, 0x8000, 0x8000 }, { 0xffff, 0x8080, 0x8080, 0x8080 }},
                        { "black", { 0x1000, 0x8000, 0x8000 }, { 0xffff, 0x0000, 0x0000, 0x0000 }},
                        { "red",   { 0x4988, 0x60b9, 0xf000 }, { 0xffff, 0xffff, 0x0000, 0x0000 }},
                        { "green", { 0xa47b, 0x2f47, 0x1902 }, { 0xffff, 0x0000, 0xffff, 0x0000 }},
                        { "blue",  { 0x1cfd, 0xf000, 0x76fe }, { 0xffff, 0x0000, 0x0000, 0xffff }},
                }
        },
};

/*
 * vkms_format_test_yuv_u16_to_argb_u16 - Testing the conversion between YUV
 * colors to ARGB colors in VKMS
 *
 * This test will use the functions get_conversion_matrix_to_argb_u16 and
 * argb_u16_from_yuv161616 to convert YUV colors (stored in
 * yuv_u16_to_argb_u16_cases) into ARGB colors.
 *
 * The conversion between YUV and RGB is not totally reversible, so there may be
 * some difference between the expected value and the result.
 */
static void vkms_format_test_yuv_u16_to_argb_u16(struct kunit *test)
{
        const struct yuv_u16_to_argb_u16_case *param = test->param_value;
        struct pixel_argb_u16 argb;

        for (size_t i = 0; i < param->n_colors; i++) {
                const struct format_pair *color = &param->colors[i];
                struct conversion_matrix matrix;

                get_conversion_matrix_to_argb_u16
                        (DRM_FORMAT_NV12, param->encoding, param->range, &matrix);

                argb = argb_u16_from_yuv161616(&matrix, color->yuv.y, color->yuv.u,
                                               color->yuv.v);

                KUNIT_EXPECT_LE_MSG(test, abs_diff(argb.a, color->argb.a), 0x1ff,
                                    "On the A channel of the color %s expected 0x%04x, got 0x%04x",
                                    color->name, color->argb.a, argb.a);
                KUNIT_EXPECT_LE_MSG(test, abs_diff(argb.r, color->argb.r), 0x1ff,
                                    "On the R channel of the color %s expected 0x%04x, got 0x%04x",
                                    color->name, color->argb.r, argb.r);
                KUNIT_EXPECT_LE_MSG(test, abs_diff(argb.g, color->argb.g), 0x1ff,
                                    "On the G channel of the color %s expected 0x%04x, got 0x%04x",
                                    color->name, color->argb.g, argb.g);
                KUNIT_EXPECT_LE_MSG(test, abs_diff(argb.b, color->argb.b), 0x1ff,
                                    "On the B channel of the color %s expected 0x%04x, got 0x%04x",
                                    color->name, color->argb.b, argb.b);
        }
}

static void vkms_format_test_yuv_u16_to_argb_u16_case_desc(struct yuv_u16_to_argb_u16_case *t,
                                                           char *desc)
{
        snprintf(desc, KUNIT_PARAM_DESC_SIZE, "%s - %s",
                 drm_get_color_encoding_name(t->encoding), drm_get_color_range_name(t->range));
}

KUNIT_ARRAY_PARAM(yuv_u16_to_argb_u16, yuv_u16_to_argb_u16_cases,
                  vkms_format_test_yuv_u16_to_argb_u16_case_desc
);

static struct kunit_case vkms_format_test_cases[] = {
        KUNIT_CASE_PARAM(vkms_format_test_yuv_u16_to_argb_u16, yuv_u16_to_argb_u16_gen_params),
        {}
};

static struct kunit_suite vkms_format_test_suite = {
        .name = "vkms-format",
        .test_cases = vkms_format_test_cases,
};

kunit_test_suite(vkms_format_test_suite);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Kunit test for vkms format conversion");