using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Collections.ObjectModel;

using System.Collections;

using System.Collections.Specialized;



namespace Microsoft.Research.DynamicDataDisplay.Common

{

	public class RingArray<T> : INotifyCollectionChanged, IList<T>

	{

		public RingArray(int capacity)

		{

			this.capacity = capacity;

			array = new T[capacity];

		}



		public void Add(T item)

		{

			int index = (startIndex + count) % capacity;

			if (startIndex + count >= capacity)

			{

				startIndex++;

			}

			else

			{

				count++;

			}



			array[index] = item;



			CollectionChanged.Raise(this);

		}



		public T this[int index]

		{

			get { return array[(startIndex + index) % capacity]; }

			set

			{

				array[(startIndex + index) % capacity] = value;

				CollectionChanged.Raise(this);

			}

		}



		public void Clear()

		{

			count = 0;

			startIndex = 0;

			array = new T[capacity];

		}



		public IEnumerator<T> GetEnumerator()

		{

			for (int i = 0; i < count; i++)

			{

				yield return this[i];

			}

		}



		private int count;

		public int Count

		{

			get { return count; }

		}



		private T[] array;



		private int capacity;

		public int Capacity

		{

			get { return capacity; }

		}



		private int startIndex = 0;



		#region INotifyCollectionChanged Members



		public event NotifyCollectionChangedEventHandler CollectionChanged;



		#endregion



		#region IList<T> Members



		public int IndexOf(T item)

		{

			int index = Array.IndexOf(array, item);



			if (index == -1)

				return -1;



			return (index - startIndex + count) % capacity;

		}



		public void Insert(int index, T item)

		{

			throw new NotImplementedException();

		}



		public void RemoveAt(int index)

		{

			throw new NotImplementedException();

		}



		#endregion



		#region ICollection<T> Members



		public bool Contains(T item)

		{

			return Array.IndexOf(array, item) > -1;

		}



		public void CopyTo(T[] array, int arrayIndex)

		{

			throw new NotImplementedException();

		}



		public bool IsReadOnly

		{

			get { throw new NotImplementedException(); }

		}



		public bool Remove(T item)

		{

			throw new NotImplementedException();

		}



		#endregion



		#region IEnumerable Members



		IEnumerator IEnumerable.GetEnumerator()

		{

			return GetEnumerator();

		}



		#endregion

	}

}