/******************************************************************************

 *  Project:		Neddle Community Edition

 *  Filename:		IteratorIsolate.cs

 *	Created By:     Kristopher Cargile <kristopher@neddle.org>

 *  Date Created:	March 29, 2011

 * ****************************************************************************

 * IMPORTANT GNU LICENSE INFORMATION. DO NOT REMOVE THIS SECTION!

 * 

 * Neddle :: Copyright (c) 2010-2012, Cargile Technology Group, LLC

 * 

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 * 

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 * 

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

 ******************************************************************************/



using System;

using System.Collections;



namespace Neddle 

{

    /// <summary>

    /// Allows you to modify the collection

    /// while within a for each loop.

    /// </summary>

    public class IteratorIsolate : IEnumerable

    {

        /// <summary>

        /// IteratorIsolateEnumerator

        /// </summary>

        internal class IteratorIsolateEnumerator : IEnumerator

        {

            protected ArrayList items = new ArrayList();

            protected int currentItem;



            /// <summary>

            /// Initializes a new instance of the <see cref="IteratorIsolateEnumerator"/> class.

            /// </summary>

            /// <param name="enumerator">The enumerator.</param>

            internal IteratorIsolateEnumerator( IEnumerator enumerator )

            {

                while(enumerator.MoveNext() != false)

                {

                    items.Add( enumerator.Current );

                }

                IDisposable disposable = enumerator as IDisposable;

                if(disposable != null)

                {

                    disposable.Dispose();

                }

                currentItem = -1;

            }



            /// <summary>

            /// Sets the enumerator to its initial position, which is before the first element in the collection.

            /// </summary>

            /// <exception cref="T:System.InvalidOperationException">The collection was modified after the enumerator was created. </exception>

            public void Reset()

            {

                currentItem = -1;

            }



            /// <summary>

            /// Advances the enumerator to the next element of the collection.

            /// </summary>

            /// <returns>

            /// true if the enumerator was successfully advanced to the next element; false if the enumerator has passed the end of the collection.

            /// </returns>

            /// <exception cref="T:System.InvalidOperationException">The collection was modified after the enumerator was created. </exception>

            public bool MoveNext()

            {

                currentItem++;

                if(currentItem == items.Count)

                    return false;



                return true;

            }



            /// <summary>

            /// Gets the current element in the collection.

            /// </summary>

            /// <value></value>

            /// <returns>The current element in the collection.</returns>

            /// <exception cref="T:System.InvalidOperationException">The enumerator is positioned before the first element of the collection or after the last element. </exception>

            public object Current

            {

                get

                {

                    return items[currentItem];

                }

            }

        }



        /// <summary>

        /// Initializes a new instance of the <see cref="IteratorIsolate"/> class.

        /// </summary>

        /// <param name="enumerable">The enumerable.</param>

        public IteratorIsolate( IEnumerable enumerable )

        {

            this.enumerable = enumerable;

        }



        /// <summary>

        /// Returns an enumerator that iterates through a collection.

        /// </summary>

        /// <returns>

        /// An <see cref="T:System.Collections.IEnumerator"></see> object that can be used to iterate through the collection.

        /// </returns>

        public IEnumerator GetEnumerator()

        {

            return new IteratorIsolateEnumerator( enumerable.GetEnumerator() );

        }

        /// <summary>

        /// 

        /// </summary>

        protected IEnumerable enumerable;

    }

}