using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace LibationWinForms
{
    class SortableBindingList2<T> : BindingList<T> where T : IObjectMemberComparable
    {
        private ObjectMemberComparer<T> Comparer = new();

        private bool isSorted;
        private ListSortDirection listSortDirection;
        private PropertyDescriptor propertyDescriptor;

        public SortableBindingList2() : base(new List<T>()) { }

        public SortableBindingList2(IEnumerable<T> enumeration) : base(new List<T>(enumeration)) { }

        protected override bool SupportsSortingCore => true;

        protected override bool IsSortedCore => isSorted;

        protected override PropertyDescriptor SortPropertyCore => propertyDescriptor;

        protected override ListSortDirection SortDirectionCore => listSortDirection;

        protected override void ApplySortCore(PropertyDescriptor property, ListSortDirection direction)
        {
            List<T> itemsList = (List<T>)Items;

            Comparer.PropertyName = property.Name;
            Comparer.Direction = direction;

            //Array.Sort and Liat<T>.Sort are unstable sorts. OrderBy is stable.
            var sortedItems = itemsList.OrderBy((ge) => ge, Comparer).ToArray();

            itemsList.Clear();
            itemsList.AddRange(sortedItems);

            propertyDescriptor = property;
            listSortDirection = direction;
            isSorted = true;

            OnListChanged(new ListChangedEventArgs(ListChangedType.Reset, -1));
        }

        protected override void RemoveSortCore()
        {
            isSorted = false;
            propertyDescriptor = base.SortPropertyCore;
            listSortDirection = base.SortDirectionCore;

            OnListChanged(new ListChangedEventArgs(ListChangedType.Reset, -1));
        }
    }
}