HawkeyeVision/Hawkeye.VisionBuilder.Workflow/Operations/Simple/Blobs/FindManyBlobsOperation.cs

using Hawkeye.VisionBuilder.Workflow.Datatypes.Elements.Origin;
using Hawkeye.VisionBuilder.Workflow.Datatypes.Elements.Poly;
using Hawkeye.VisionBuilder.Workflow.Datatypes.Elements.Rectangle;
using Hawkeye.VisionBuilder.Workflow.Operations.Attributes;

using OpenCvSharp;
using Point = OpenCvSharp.Point;

namespace Hawkeye.VisionBuilder.Workflow.Operations;

[Category("Simple/Blobs")]
public class FindManyBlobsOperation:BaseOperation
{
    private readonly WorkflowList _workflowList;

    public int MinArea { get; set; } = 100;

    public int MaxArea { get; set; } = 99999;

    public int MinRadius { get; set; } = 0;

    public int MaxRadius { get; set; } = 99999;

    



    public Guid ReferenceId { get; set; } = new Guid();

    public RectangleElement SearchArea { get; set; }

    //processing result of current element
    

    public FindManyBlobsOperation(WorkflowList workflowList)
    {
        _workflowList = workflowList;
        SearchArea = new RectangleElement()
        {
            Editable = true,
            Location = Vector2.One * 100,
            Size = Vector2.One * 100,
            IsGood = true
        };
    }


    public record ContourMatch(Point[] c, int area, int radius)
    {
        

        public override string ToString()
        {
            return $"{{area={area}, radius={radius}}}";
        }
    }

    protected override void InterpretInternal(Context context)
    {
        Result = true;
        if (!CheckImageExists(context)) return;
        if (!CheckGrayscale(context)) return;

        if (SearchArea==null)
        {
            SearchArea = new RectangleElement()
            {
                Editable = true,
                Location = Vector2.Zero,
                Size = new Vector2(context.ActiveImage.ImageData.Width, context.ActiveImage.ImageData.Height),
                IsGood = true
            };
        }

        SearchArea.MovePivot(_workflowList.GetOriginById(ReferenceId).Origin.Location);

        var img = context.ActiveImage.ImageData;
        var mat = new Mat(img.Size(), img.Type(), Scalar.Black);

        SearchArea.FillMat(mat);

        var contoursMat = img.BitwiseAnd(mat).ToMat();


        var contours = contoursMat.Threshold(128, 255, ThresholdTypes.Binary)
            .FindContoursAsArray(RetrievalModes.List, ContourApproximationModes.ApproxSimple);
        context.GraphicsElements.Add(SearchArea);
        //case: no blobs found
        if (contours.Length == 0)
        {
            Status = "No blobs found";
            SearchArea.IsGood = true;
            
            return;
        }

        int GetContourRadius(Point[] contour)
        {
            Cv2.MinEnclosingCircle(contour, out var center, out var radius);
            return (int)radius;
        }
        //case: blobs found but not matching criteria
        var contour = contours.Select(x => new ContourMatch(x, (int)Cv2.ContourArea(x), GetContourRadius(x)))
            .OrderBy(x => Math.Min(Math.Abs(x.area - MinArea), Math.Abs(x.area - MaxArea))).ToList();
        var match = contour.Where(x => x.c.Length > 1)
            .Where(x => x.area >= MinArea && x.area <= MaxArea)
            .Where(x => x.radius >= MinRadius && x.radius <= MaxRadius).ToList();



        int badCount = 0;
        foreach (ContourMatch contourMatch in match)
        {
            PolyElement poly = new PolyElement() { IsGood = false };

            poly.Points = contourMatch.c.Select(x => new Vector2(x.X, x.Y)).ToArray();

            context.GraphicsElements.Add(poly);
            badCount++;
        }



        if (badCount > 0)
        {
            Status = $"Found: {badCount} First: {match.First().ToString()}";
            Result = false;
            SearchArea.IsGood = false;
            return;
        }

        SearchArea.IsGood = true;
        Status = $"Best: {contour.First().ToString()}";
        Result = true;



    }

    public override void SetParameters(Dictionary<string, object> parameters)
    {
        base.SetParameters(parameters);

        SearchArea.SetPivot(_workflowList.GetOriginById(ReferenceId).Origin.Location);
    }


    public override void Save(BinaryWriter bw)
    {
        bw.Write(Id.ToString());
        bw.Write(Label);
        bw.Write(MinArea);
        bw.Write(MaxArea);
        bw.Write(MinRadius);
        bw.Write(MaxRadius);
        bw.Write(ReferenceId.ToString());

        SearchArea.Save(bw);


    }

    public override void Load(BinaryReader br)
    {
        Id = new Guid(br.ReadString());
        Label = br.ReadString();
        MinArea = br.ReadInt32();
        MaxArea = br.ReadInt32();
        MinRadius = br.ReadInt32();
        MaxRadius = br.ReadInt32();
        ReferenceId = new Guid(br.ReadString());

        SearchArea.Load(br);
    }
}