// Generated by Sichem at 12/24/2021 8:28:15 PM

using Misaki.HighPerformance.Image.Runtime;
// Generated by Sichem at 12/24/2021 8:28:15 PM


namespace Misaki.HighPerformance.Image
{
    public unsafe partial class StbImage
    {
        public static int stbi__tga_test(stbi__context s)
        {
            var res = 0;
            var sz = 0;
            var tga_color_type = 0;
            stbi__get8(s);
            tga_color_type = stbi__get8(s);
            if (tga_color_type > 1)
            {
                goto errorEnd;
            }

            sz = stbi__get8(s);
            if (tga_color_type == 1)
            {
                if (sz != 1 && sz != 9)
                {
                    goto errorEnd;
                }

                stbi__skip(s, 4);
                sz = stbi__get8(s);
                if (sz != 8 && sz != 15 && sz != 16 && sz != 24 && sz != 32)
                {
                    goto errorEnd;
                }

                stbi__skip(s, 4);
            }
            else
            {
                if (sz != 2 && sz != 3 && sz != 10 && sz != 11)
                {
                    goto errorEnd;
                }

                stbi__skip(s, 9);
            }

            if (stbi__get16le(s) < 1)
            {
                goto errorEnd;
            }

            if (stbi__get16le(s) < 1)
            {
                goto errorEnd;
            }

            sz = stbi__get8(s);
            if (tga_color_type == 1 && sz != 8 && sz != 16)
            {
                goto errorEnd;
            }

            if (sz != 8 && sz != 15 && sz != 16 && sz != 24 && sz != 32)
            {
                goto errorEnd;
            }

            res = 1;
        errorEnd:
            ;
            stbi__rewind(s);
            return res;
        }

        public static void* stbi__tga_load(stbi__context s, int* x, int* y, int* comp, int req_comp,
            stbi__result_info* ri)
        {
            int tga_offset = stbi__get8(s);
            int tga_indexed = stbi__get8(s);
            int tga_image_type = stbi__get8(s);
            var tga_is_RLE = 0;
            var tga_palette_start = stbi__get16le(s);
            var tga_palette_len = stbi__get16le(s);
            int tga_palette_bits = stbi__get8(s);
            var tga_x_origin = stbi__get16le(s);
            var tga_y_origin = stbi__get16le(s);
            var tga_width = stbi__get16le(s);
            var tga_height = stbi__get16le(s);
            int tga_bits_per_pixel = stbi__get8(s);
            var tga_comp = 0;
            var tga_rgb16 = 0;
            int tga_inverted = stbi__get8(s);
            byte* tga_data;
            byte* tga_palette = null;
            var i = 0;
            var j = 0;
            var raw_data = stackalloc byte[4];
            raw_data[0] = 0;
            raw_data[1] = 0;
            raw_data[2] = 0;
            raw_data[3] = 0;
            var RLE_count = 0;
            var RLE_repeating = 0;
            var read_next_pixel = 1;
            if (tga_height > 1 << 24)
            {
                return (byte*)(ulong)(stbi__err("too large") != 0 ? 0 : 0);
            }

            if (tga_width > 1 << 24)
            {
                return (byte*)(ulong)(stbi__err("too large") != 0 ? 0 : 0);
            }

            if (tga_image_type >= 8)
            {
                tga_image_type -= 8;
                tga_is_RLE = 1;
            }

            tga_inverted = 1 - ((tga_inverted >> 5) & 1);
            if (tga_indexed != 0)
            {
                tga_comp = stbi__tga_get_comp(tga_palette_bits, 0, &tga_rgb16);
            }
            else
            {
                tga_comp = stbi__tga_get_comp(tga_bits_per_pixel, tga_image_type == 3 ? 1 : 0, &tga_rgb16);
            }

            if (tga_comp == 0)
            {
                return (byte*)(ulong)(stbi__err("bad format") != 0 ? 0 : 0);
            }

            *x = tga_width;
            *y = tga_height;
            if (comp != null)
            {
                *comp = tga_comp;
            }

            if (stbi__mad3sizes_valid(tga_width, tga_height, tga_comp, 0) == 0)
            {
                return (byte*)(ulong)(stbi__err("too large") != 0 ? 0 : 0);
            }

            tga_data = (byte*)stbi__malloc_mad3(tga_width, tga_height, tga_comp, 0);
            if (tga_data == null)
            {
                return (byte*)(ulong)(stbi__err("outofmem") != 0 ? 0 : 0);
            }

            stbi__skip(s, tga_offset);
            if (tga_indexed == 0 && tga_is_RLE == 0 && tga_rgb16 == 0)
            {
                for (i = 0; i < tga_height; ++i)
                {
                    var row = tga_inverted != 0 ? tga_height - i - 1 : i;
                    var tga_row = tga_data + row * tga_width * tga_comp;
                    stbi__getn(s, tga_row, tga_width * tga_comp);
                }
            }
            else
            {
                if (tga_indexed != 0)
                {
                    if (tga_palette_len == 0)
                    {
                        CRuntime.free(tga_data);
                        return (byte*)(ulong)(stbi__err("bad palette") != 0 ? 0 : 0);
                    }

                    stbi__skip(s, tga_palette_start);
                    tga_palette = (byte*)stbi__malloc_mad2(tga_palette_len, tga_comp, 0);
                    if (tga_palette == null)
                    {
                        CRuntime.free(tga_data);
                        return (byte*)(ulong)(stbi__err("outofmem") != 0 ? 0 : 0);
                    }

                    if (tga_rgb16 != 0)
                    {
                        var pal_entry = tga_palette;
                        for (i = 0; i < tga_palette_len; ++i)
                        {
                            stbi__tga_read_rgb16(s, pal_entry);
                            pal_entry += tga_comp;
                        }
                    }
                    else if (stbi__getn(s, tga_palette, tga_palette_len * tga_comp) == 0)
                    {
                        CRuntime.free(tga_data);
                        CRuntime.free(tga_palette);
                        return (byte*)(ulong)(stbi__err("bad palette") != 0 ? 0 : 0);
                    }
                }

                for (i = 0; i < tga_width * tga_height; ++i)
                {
                    if (tga_is_RLE != 0)
                    {
                        if (RLE_count == 0)
                        {
                            int RLE_cmd = stbi__get8(s);
                            RLE_count = 1 + (RLE_cmd & 127);
                            RLE_repeating = RLE_cmd >> 7;
                            read_next_pixel = 1;
                        }
                        else if (RLE_repeating == 0)
                        {
                            read_next_pixel = 1;
                        }
                    }
                    else
                    {
                        read_next_pixel = 1;
                    }

                    if (read_next_pixel != 0)
                    {
                        if (tga_indexed != 0)
                        {
                            var pal_idx = tga_bits_per_pixel == 8 ? stbi__get8(s) : stbi__get16le(s);
                            if (pal_idx >= tga_palette_len)
                            {
                                pal_idx = 0;
                            }

                            pal_idx *= tga_comp;
                            for (j = 0; j < tga_comp; ++j)
                            {
                                raw_data[j] = tga_palette[pal_idx + j];
                            }
                        }
                        else if (tga_rgb16 != 0)
                        {
                            stbi__tga_read_rgb16(s, raw_data);
                        }
                        else
                        {
                            for (j = 0; j < tga_comp; ++j)
                            {
                                raw_data[j] = stbi__get8(s);
                            }
                        }

                        read_next_pixel = 0;
                    }

                    for (j = 0; j < tga_comp; ++j)
                    {
                        tga_data[i * tga_comp + j] = raw_data[j];
                    }

                    --RLE_count;
                }

                if (tga_inverted != 0)
                {
                    for (j = 0; j * 2 < tga_height; ++j)
                    {
                        var index1 = j * tga_width * tga_comp;
                        var index2 = (tga_height - 1 - j) * tga_width * tga_comp;
                        for (i = tga_width * tga_comp; i > 0; --i)
                        {
                            var temp = tga_data[index1];
                            tga_data[index1] = tga_data[index2];
                            tga_data[index2] = temp;
                            ++index1;
                            ++index2;
                        }
                    }
                }

                if (tga_palette != null)
                {
                    CRuntime.free(tga_palette);
                }
            }

            if (tga_comp >= 3 && tga_rgb16 == 0)
            {
                var tga_pixel = tga_data;
                for (i = 0; i < tga_width * tga_height; ++i)
                {
                    var temp = tga_pixel[0];
                    tga_pixel[0] = tga_pixel[2];
                    tga_pixel[2] = temp;
                    tga_pixel += tga_comp;
                }
            }

            if (req_comp != 0 && req_comp != tga_comp)
            {
                tga_data = stbi__convert_format(tga_data, tga_comp, req_comp, (uint)tga_width, (uint)tga_height);
            }

            tga_palette_start = tga_palette_len = tga_palette_bits = tga_x_origin = tga_y_origin = 0;
            return tga_data;
        }

        public static int stbi__tga_info(stbi__context s, int* x, int* y, int* comp)
        {
            var tga_w = 0;
            var tga_h = 0;
            var tga_comp = 0;
            var tga_image_type = 0;
            var tga_bits_per_pixel = 0;
            var tga_colormap_bpp = 0;
            var sz = 0;
            var tga_colormap_type = 0;
            stbi__get8(s);
            tga_colormap_type = stbi__get8(s);
            if (tga_colormap_type > 1)
            {
                stbi__rewind(s);
                return 0;
            }

            tga_image_type = stbi__get8(s);
            if (tga_colormap_type == 1)
            {
                if (tga_image_type != 1 && tga_image_type != 9)
                {
                    stbi__rewind(s);
                    return 0;
                }

                stbi__skip(s, 4);
                sz = stbi__get8(s);
                if (sz != 8 && sz != 15 && sz != 16 && sz != 24 && sz != 32)
                {
                    stbi__rewind(s);
                    return 0;
                }

                stbi__skip(s, 4);
                tga_colormap_bpp = sz;
            }
            else
            {
                if (tga_image_type != 2 && tga_image_type != 3 && tga_image_type != 10 && tga_image_type != 11)
                {
                    stbi__rewind(s);
                    return 0;
                }

                stbi__skip(s, 9);
                tga_colormap_bpp = 0;
            }

            tga_w = stbi__get16le(s);
            if (tga_w < 1)
            {
                stbi__rewind(s);
                return 0;
            }

            tga_h = stbi__get16le(s);
            if (tga_h < 1)
            {
                stbi__rewind(s);
                return 0;
            }

            tga_bits_per_pixel = stbi__get8(s);
            stbi__get8(s);
            if (tga_colormap_bpp != 0)
            {
                if (tga_bits_per_pixel != 8 && tga_bits_per_pixel != 16)
                {
                    stbi__rewind(s);
                    return 0;
                }

                tga_comp = stbi__tga_get_comp(tga_colormap_bpp, 0, null);
            }
            else
            {
                tga_comp = stbi__tga_get_comp(tga_bits_per_pixel, tga_image_type == 3 || tga_image_type == 11 ? 1 : 0,
                    null);
            }

            if (tga_comp == 0)
            {
                stbi__rewind(s);
                return 0;
            }

            if (x != null)
            {
                *x = tga_w;
            }

            if (y != null)
            {
                *y = tga_h;
            }

            if (comp != null)
            {
                *comp = tga_comp;
            }

            return 1;
        }

        public static int stbi__tga_get_comp(int bits_per_pixel, int is_grey, int* is_rgb16)
        {
            if (is_rgb16 != null)
            {
                *is_rgb16 = 0;
            }

            switch (bits_per_pixel)
            {
                case 8:
                    return STBI_grey;
                case 16:
                case 15:
                    if (bits_per_pixel == 16 && is_grey != 0)
                    {
                        return STBI_grey_alpha;
                    }

                    if (is_rgb16 != null)
                    {
                        *is_rgb16 = 1;
                    }

                    return STBI_rgb;
                case 24:
                case 32:
                    return bits_per_pixel / 8;
                default:
                    return 0;
            }
        }

        public static void stbi__tga_read_rgb16(stbi__context s, byte* _out_)
        {
            var px = (ushort)stbi__get16le(s);
            ushort fiveBitMask = 31;
            var r = (px >> 10) & fiveBitMask;
            var g = (px >> 5) & fiveBitMask;
            var b = px & fiveBitMask;
            _out_[0] = (byte)(r * 255 / 31);
            _out_[1] = (byte)(g * 255 / 31);
            _out_[2] = (byte)(b * 255 / 31);
        }
    }
}