#nullable disable
using System;
using System.Collections.Generic;
using System.Text;
using Foundation;
using Microsoft.Maui.Handlers;
using ObjCRuntime;
using UIKit;
 
namespace Microsoft.Maui.Controls.Handlers.Items
{
	public partial class GroupableItemsViewHandler<TItemsView> : SelectableItemsViewHandler<TItemsView> where TItemsView : GroupableItemsView
	{
		protected override ItemsViewController<TItemsView> CreateController(TItemsView itemsView, ItemsViewLayout layout)
			 => new GroupableItemsViewController<TItemsView>(itemsView, layout);
 
		protected override void ScrollToRequested(object sender, ScrollToRequestEventArgs args)
		{
			if (WillNeedScrollAdjustment(args))
			{
				if (args.IsAnimated)
				{
					(Controller as GroupableItemsViewController<TItemsView>).SetScrollAnimationEndedCallback(() => base.ScrollToRequested(sender, args));
				}
				else
				{
					base.ScrollToRequested(sender, args);
				}
			}
 
			base.ScrollToRequested(sender, args);
		}
 
		public static void MapIsGrouped(GroupableItemsViewHandler<TItemsView> handler, GroupableItemsView itemsView)
		{
			handler.Controller?.UpdateItemsSource();
		}
 
		bool WillNeedScrollAdjustment(ScrollToRequestEventArgs args)
		{
			return ItemsView.ItemSizingStrategy == ItemSizingStrategy.MeasureAllItems
				&& ItemsView.IsGrouped
				&& (args.ScrollToPosition == ScrollToPosition.End || args.ScrollToPosition == ScrollToPosition.MakeVisible);
		}
	}
}