Adaptor

using System;
using DynamicData.Cache.Internal;

namespace DynamicData.Binding
{
    public class MyObservableCollectionAdaptor<TObject, TKey> : IObservableCollectionAdaptor<TObject, TKey>
        where TKey : notnull
    {
        private readonly Cache<TObject, TKey> _cache = new();

        private readonly int _refreshThreshold;

        private bool _loaded;

        public MyObservableCollectionAdaptor(int refreshThreshold = 25) => _refreshThreshold = refreshThreshold;

        public void Adapt(IChangeSet<TObject, TKey> changes, IObservableCollection<TObject> collection)
        {
            if (changes is null)
            {
                throw new ArgumentNullException(nameof(changes));
            }

            if (collection is null)
            {
                throw new ArgumentNullException(nameof(collection));
            }

            _cache.Clone(changes);

            if (changes.Count - changes.Refreshes > _refreshThreshold || !_loaded)
            {
                _loaded = true;
                using (collection.SuspendNotifications())
                {
                    collection.Load(_cache.Items);
                }
            }
            else
            {
                using (collection.SuspendCount())
                {
                    DoUpdate(changes, collection);
                }
            }
        }

        private static void DoUpdate(IChangeSet<TObject, TKey> updates, IObservableCollection<TObject> list)
        {
            foreach (var update in updates)
            {
                switch (update.Reason)
                {
                    case ChangeReason.Add:
                        list.Add(update.Current);
                        break;

                    case ChangeReason.Remove:
                        list.Remove(update.Current);
                        break;

                    //This was changed in a PR 1 year ago and my be the problem. 
                    case ChangeReason.Update:
                        list.Replace(update.Previous.Value, update.Current);
                        break;
                }
            }
        }
    }
}