//---------------------------------------------------------------------------
//
// Copyright (c) Microsoft Corporation.  All rights reserved.
// 
//
// Description: A class that implements ICollection<ushort> for a sequence of numbers [0..n-1].
// 
//
// History:  
//  03/21/2005 : MLeonov - Created it.
//
//---------------------------------------------------------------------------
 
using System;
using System.Windows;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using System.Text;
using System.Runtime.InteropServices;
 
using SR=MS.Internal.PresentationCore.SR;
using SRID=MS.Internal.PresentationCore.SRID;
 
namespace MS.Internal
{
    internal class SequentialUshortCollection : ICollection<ushort>
    {
        public SequentialUshortCollection(ushort count)
        {
            _count = count;
        }
 
        #region ICollection<ushort> Members
 
        public void Add(ushort item)
        {
            throw new NotSupportedException();
        }
 
        public void Clear()
        {
            throw new NotSupportedException();
        }
 
        public bool Contains(ushort item)
        {
            return item < _count;
        }
 
        public void CopyTo(ushort[] array, int arrayIndex)
        {
            if (array == null)
            {
                throw new ArgumentNullException("array");
            }
 
            if (array.Rank != 1)
            {
                throw new ArgumentException(SR.Get(SRID.Collection_BadRank));
            }
 
            // The extra "arrayIndex >= array.Length" check in because even if _collection.Count
            // is 0 the index is not allowed to be equal or greater than the length
            // (from the MSDN ICollection docs)
            if (arrayIndex < 0 || arrayIndex >= array.Length || (arrayIndex + Count) > array.Length)
            {
                throw new ArgumentOutOfRangeException("arrayIndex");
            }
 
            for (ushort i = 0; i < _count; ++i)
                array[arrayIndex + i] = i;
        }
 
        public int Count
        {
            get { return _count; }
        }
 
        public bool IsReadOnly
        {
            get { return true; }
        }
 
        public bool Remove(ushort item)
        {
            throw new NotSupportedException();
        }
 
        #endregion
 
        #region IEnumerable<ushort> Members
 
        public IEnumerator<ushort> GetEnumerator()
        {
            for (ushort i = 0; i < _count; ++i)
                yield return i;
        }
 
        #endregion
 
        #region IEnumerable Members
 
        IEnumerator IEnumerable.GetEnumerator()
        {
            return ((IEnumerable<ushort>)this).GetEnumerator();
        }
 
        #endregion
 
        private ushort _count;
    }
}