// 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__psd_test(stbi__context s)
        {
            var r = stbi__get32be(s) == 0x38425053 ? 1 : 0;
            stbi__rewind(s);
            return r;
        }

        public static void* stbi__psd_load(stbi__context s, int* x, int* y, int* comp, int req_comp,
            stbi__result_info* ri, int bpc)
        {
            var pixelCount = 0;
            var channelCount = 0;
            var compression = 0;
            var channel = 0;
            var i = 0;
            var bitdepth = 0;
            var w = 0;
            var h = 0;
            byte* _out_;
            if (stbi__get32be(s) != 0x38425053)
            {
                return (byte*)(ulong)(stbi__err("not PSD") != 0 ? 0 : 0);
            }

            if (stbi__get16be(s) != 1)
            {
                return (byte*)(ulong)(stbi__err("wrong version") != 0 ? 0 : 0);
            }

            stbi__skip(s, 6);
            channelCount = stbi__get16be(s);
            if (channelCount < 0 || channelCount > 16)
            {
                return (byte*)(ulong)(stbi__err("wrong channel count") != 0 ? 0 : 0);
            }

            h = (int)stbi__get32be(s);
            w = (int)stbi__get32be(s);
            if (h > 1 << 24)
            {
                return (byte*)(ulong)(stbi__err("too large") != 0 ? 0 : 0);
            }

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

            bitdepth = stbi__get16be(s);
            if (bitdepth != 8 && bitdepth != 16)
            {
                return (byte*)(ulong)(stbi__err("unsupported bit depth") != 0 ? 0 : 0);
            }

            if (stbi__get16be(s) != 3)
            {
                return (byte*)(ulong)(stbi__err("wrong color format") != 0 ? 0 : 0);
            }

            stbi__skip(s, (int)stbi__get32be(s));
            stbi__skip(s, (int)stbi__get32be(s));
            stbi__skip(s, (int)stbi__get32be(s));
            compression = stbi__get16be(s);
            if (compression > 1)
            {
                return (byte*)(ulong)(stbi__err("bad compression") != 0 ? 0 : 0);
            }

            if (stbi__mad3sizes_valid(4, w, h, 0) == 0)
            {
                return (byte*)(ulong)(stbi__err("too large") != 0 ? 0 : 0);
            }

            if (compression == 0 && bitdepth == 16 && bpc == 16)
            {
                _out_ = (byte*)stbi__malloc_mad3(8, w, h, 0);
                ri->bits_per_channel = 16;
            }
            else
            {
                _out_ = (byte*)stbi__malloc((ulong)(4 * w * h));
            }

            if (_out_ == null)
            {
                return (byte*)(ulong)(stbi__err("outofmem") != 0 ? 0 : 0);
            }

            pixelCount = w * h;
            if (compression != 0)
            {
                stbi__skip(s, h * channelCount * 2);
                for (channel = 0; channel < 4; channel++)
                {
                    byte* p;
                    p = _out_ + channel;
                    if (channel >= channelCount)
                    {
                        for (i = 0; i < pixelCount; i++, p += 4)
                        {
                            *p = (byte)(channel == 3 ? 255 : 0);
                        }
                    }
                    else
                    {
                        if (stbi__psd_decode_rle(s, p, pixelCount) == 0)
                        {
                            CRuntime.free(_out_);
                            return (byte*)(ulong)(stbi__err("corrupt") != 0 ? 0 : 0);
                        }
                    }
                }
            }
            else
            {
                for (channel = 0; channel < 4; channel++)
                {
                    if (channel >= channelCount)
                    {
                        if (bitdepth == 16 && bpc == 16)
                        {
                            var q = (ushort*)_out_ + channel;
                            var val = (ushort)(channel == 3 ? 65535 : 0);
                            for (i = 0; i < pixelCount; i++, q += 4)
                            {
                                *q = val;
                            }
                        }
                        else
                        {
                            var p = _out_ + channel;
                            var val = (byte)(channel == 3 ? 255 : 0);
                            for (i = 0; i < pixelCount; i++, p += 4)
                            {
                                *p = val;
                            }
                        }
                    }
                    else
                    {
                        if (ri->bits_per_channel == 16)
                        {
                            var q = (ushort*)_out_ + channel;
                            for (i = 0; i < pixelCount; i++, q += 4)
                            {
                                *q = (ushort)stbi__get16be(s);
                            }
                        }
                        else
                        {
                            var p = _out_ + channel;
                            if (bitdepth == 16)
                            {
                                for (i = 0; i < pixelCount; i++, p += 4)
                                {
                                    *p = (byte)(stbi__get16be(s) >> 8);
                                }
                            }
                            else
                            {
                                for (i = 0; i < pixelCount; i++, p += 4)
                                {
                                    *p = stbi__get8(s);
                                }
                            }
                        }
                    }
                }
            }

            if (channelCount >= 4)
            {
                if (ri->bits_per_channel == 16)
                {
                    for (i = 0; i < w * h; ++i)
                    {
                        var pixel = (ushort*)_out_ + 4 * i;
                        if (pixel[3] != 0 && pixel[3] != 65535)
                        {
                            var a = pixel[3] / 65535.0f;
                            var ra = 1.0f / a;
                            var inv_a = 65535.0f * (1 - ra);
                            pixel[0] = (ushort)(pixel[0] * ra + inv_a);
                            pixel[1] = (ushort)(pixel[1] * ra + inv_a);
                            pixel[2] = (ushort)(pixel[2] * ra + inv_a);
                        }
                    }
                }
                else
                {
                    for (i = 0; i < w * h; ++i)
                    {
                        var pixel = _out_ + 4 * i;
                        if (pixel[3] != 0 && pixel[3] != 255)
                        {
                            var a = pixel[3] / 255.0f;
                            var ra = 1.0f / a;
                            var inv_a = 255.0f * (1 - ra);
                            pixel[0] = (byte)(pixel[0] * ra + inv_a);
                            pixel[1] = (byte)(pixel[1] * ra + inv_a);
                            pixel[2] = (byte)(pixel[2] * ra + inv_a);
                        }
                    }
                }
            }

            if (req_comp != 0 && req_comp != 4)
            {
                if (ri->bits_per_channel == 16)
                {
                    _out_ = (byte*)stbi__convert_format16((ushort*)_out_, 4, req_comp, (uint)w, (uint)h);
                }
                else
                {
                    _out_ = stbi__convert_format(_out_, 4, req_comp, (uint)w, (uint)h);
                }

                if (_out_ == null)
                {
                    return _out_;
                }
            }

            if (comp != null)
            {
                *comp = 4;
            }

            *y = h;
            *x = w;
            return _out_;
        }

        public static int stbi__psd_info(stbi__context s, int* x, int* y, int* comp)
        {
            var channelCount = 0;
            var dummy = 0;
            var depth = 0;
            if (x == null)
            {
                x = &dummy;
            }

            if (y == null)
            {
                y = &dummy;
            }

            if (comp == null)
            {
                comp = &dummy;
            }

            if (stbi__get32be(s) != 0x38425053)
            {
                stbi__rewind(s);
                return 0;
            }

            if (stbi__get16be(s) != 1)
            {
                stbi__rewind(s);
                return 0;
            }

            stbi__skip(s, 6);
            channelCount = stbi__get16be(s);
            if (channelCount < 0 || channelCount > 16)
            {
                stbi__rewind(s);
                return 0;
            }

            *y = (int)stbi__get32be(s);
            *x = (int)stbi__get32be(s);
            depth = stbi__get16be(s);
            if (depth != 8 && depth != 16)
            {
                stbi__rewind(s);
                return 0;
            }

            if (stbi__get16be(s) != 3)
            {
                stbi__rewind(s);
                return 0;
            }

            *comp = 4;
            return 1;
        }

        public static int stbi__psd_is16(stbi__context s)
        {
            var channelCount = 0;
            var depth = 0;
            if (stbi__get32be(s) != 0x38425053)
            {
                stbi__rewind(s);
                return 0;
            }

            if (stbi__get16be(s) != 1)
            {
                stbi__rewind(s);
                return 0;
            }

            stbi__skip(s, 6);
            channelCount = stbi__get16be(s);
            if (channelCount < 0 || channelCount > 16)
            {
                stbi__rewind(s);
                return 0;
            }

            depth = stbi__get16be(s);
            if (depth != 16)
            {
                stbi__rewind(s);
                return 0;
            }

            return 1;
        }

        public static int stbi__psd_decode_rle(stbi__context s, byte* p, int pixelCount)
        {
            var count = 0;
            var nleft = 0;
            var len = 0;
            count = 0;
            while ((nleft = pixelCount - count) > 0)
            {
                len = stbi__get8(s);
                if (len == 128)
                {
                }
                else if (len < 128)
                {
                    len++;
                    if (len > nleft)
                    {
                        return 0;
                    }

                    count += len;
                    while (len != 0)
                    {
                        *p = stbi__get8(s);
                        p += 4;
                        len--;
                    }
                }
                else if (len > 128)
                {
                    byte val = 0;
                    len = 257 - len;
                    if (len > nleft)
                    {
                        return 0;
                    }

                    val = stbi__get8(s);
                    count += len;
                    while (len != 0)
                    {
                        *p = val;
                        p += 4;
                        len--;
                    }
                }
            }

            return 1;
        }
    }
}