NetworkTest/Client/FrameAssembler.cs

using System;
using System.Collections.Generic;
using System.Linq;
using Domain;

namespace Client;

public class FrameAssembler
{
    private readonly Action<List<Data>> _frameCallback;
    private readonly Dictionary<long, Dictionary<string, Data>> _frames = new();
    private const int FrameSize = 9;

    public FrameAssembler(Action<List<Data>> frameCallback)
    {
        _frameCallback = frameCallback ?? throw new ArgumentNullException(nameof(frameCallback));
    }

    public void AddData(Data data)
    {
        long frameIndex = data.FrameIndex;
        string overlayPoint = data.OverlayPoint;

        if (!_frames.ContainsKey(frameIndex))
        {
            _frames[frameIndex] = new Dictionary<string, Data>();
        }

        _frames[frameIndex][overlayPoint] = data; // Overwrite if duplicate

        if (_frames[frameIndex].Count == FrameSize)
        {
            List<Data> frameData = _frames[frameIndex].Values
                .OrderBy(d => d.OverlayPoint)
                .ToList();
            _frameCallback(frameData);
            _frames.Remove(frameIndex);
        }
    }
}