using System.Collections;
using System.Collections.ObjectModel;
using System.Collections.Specialized;
using System.ComponentModel;

namespace FruitBank.Common
{
    public interface IMgFastObservableCollection
    {
        public void AddRange(IEnumerable other);
        public void Replace(IEnumerable other);
        public void RemoveRange(IEnumerable other);
        public void Synchronize(NotifyCollectionChangedEventArgs args);
    }

    public interface IMgFastObservableCollection<T> : IMgFastObservableCollection
    {
        public void Replace(IEnumerable<T> other);
        public void Sort(IComparer<T> comparer);
        public void SortAndReplace(IEnumerable<T> other, IComparer<T> comparer);
    }

    public class MgObservableCollection<T> : ObservableCollection<T>, IMgFastObservableCollection<T>
    {
        private bool _suppressChangedEvent;

        public void Replace(IEnumerable<T> other)
        {
            _suppressChangedEvent = true;

            Clear();
            AddRange(other);
        }

        public void Replace(IEnumerable other)
        {
            _suppressChangedEvent = true;

            Clear();
            foreach (T item in other) Add(item);

            _suppressChangedEvent = false;

            OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
            OnPropertyChanged(new PropertyChangedEventArgs(nameof(Count)));
        }

        public void AddRange(IEnumerable other)
        {
            _suppressChangedEvent = true;

            foreach (var item in other)
            {
                if (item is T tItem) Add(tItem);
            }

            _suppressChangedEvent = false;

            OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
            OnPropertyChanged(new PropertyChangedEventArgs(nameof(Count)));
        }

        public void RemoveRange(IEnumerable other)
        {
            _suppressChangedEvent = true;

            foreach (var item in other)
            {
                if (item is T tItem) Remove(tItem);
            }

            _suppressChangedEvent = false;

            OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
            OnPropertyChanged(new PropertyChangedEventArgs(nameof(Count)));
        }

        public void SortAndReplace(IEnumerable<T> other, IComparer<T> comparer)
        {
            List<T> values = new(other);

            values.Sort(comparer);
            Replace(values);
        }

        public void Sort(IComparer<T> comparer)
        {
            List<T> values = new(this);

            values.Sort(comparer);
            Replace(values);
        }

        public void Synchronize(NotifyCollectionChangedEventArgs args)
        {
            switch (args.Action)
            {
                case NotifyCollectionChangedAction.Add when args.NewItems != null:
                    AddRange(args.NewItems);
                    break;
                case NotifyCollectionChangedAction.Remove when args.OldItems != null:
                    RemoveRange(args.OldItems);
                    break;
                case NotifyCollectionChangedAction.Reset:
                    Clear();
                    break;
                case NotifyCollectionChangedAction.Replace:
                case NotifyCollectionChangedAction.Move:
                    break;
                default:
                    throw new ArgumentOutOfRangeException();
            }
        }

        protected override void OnPropertyChanged(PropertyChangedEventArgs e)
        {
            if (_suppressChangedEvent)
                return;

            base.OnPropertyChanged(e);
        }

        protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
        {
            if (_suppressChangedEvent)
                return;

            base.OnCollectionChanged(e);
        }

        //protected override void ClearItems()
        //{
        //    base.ClearItems();
        //}

        //protected override void InsertItem(int index, T item)
        //{
        //    base.InsertItem(index, item);
        //}

        //protected override void MoveItem(int oldIndex, int newIndex)
        //{
        //    base.MoveItem(oldIndex, newIndex);
        //}

        //public override event NotifyCollectionChangedEventHandler? CollectionChanged
        //{
        //    add => base.CollectionChanged += value;
        //    remove => base.CollectionChanged -= value;
        //}
    }
}