using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Collections.Specialized;

using Microsoft.Research.DynamicDataDisplay.Charts;



namespace Microsoft.Research.DynamicDataDisplay.Common.Auxiliary

{

	public static class NotifyCollectionChangedEventArgsExtensions

	{

		public static int GetLastAddedIndex(this NotifyCollectionChangedEventArgs args)

		{

			if (args.NewItems == null)

				throw new InvalidOperationException("Cannot get last added index when NewItems are null.");



			int lastIndex = args.NewStartingIndex + args.NewItems.Count;



			return lastIndex;

		}



		public static Range<int> GetAddedRange(this NotifyCollectionChangedEventArgs args)

		{

			int lastIndex = GetLastAddedIndex(args);



			return new Range<int>(args.NewStartingIndex, lastIndex);

		}

	}

}