/// <summary>
		/// Retrieve all Freedb servers from the main server site
		/// </summary>
		/// <param name="sites">SiteCollection that is populated with the site information</param>
		/// <returns>Response Code</returns>
		public string GetSites(out SiteCollection sites)
		{
			return GetSites(Site.PROTOCOLS.ALL, out sites);
		}
		/// <summary>
		/// Get the Freedb sites
		/// </summary>
		/// <param name="protocol"></param>
		/// <param name="sites">SiteCollection that is populated with the site information</param>
		/// <returns>Response Code</returns>
		/// 
		public string GetSites(string protocol, out SiteCollection sites)
		{
			if (protocol != Site.PROTOCOLS.CDDBP && protocol != Site.PROTOCOLS.HTTP)
				protocol = Site.PROTOCOLS.ALL;

			StringCollection coll;

			try
			{
				coll = Call(Commands.CMD_SITES, m_mainSite.GetUrl());
			}

			catch (Exception ex)
			{
				Debug.WriteLine("Error retrieving Sites." + ex.Message);
				Exception newEx = new Exception("FreedbHelper.GetSites: Error retrieving Sites.", ex);
				throw newEx;
			}

			sites = null;

			// check if results came back
			if (coll.Count < 0)
			{
				string msg = "No results returned from sites request.";
				Exception ex = new Exception(msg, null);
				throw ex;
			}

			string code = GetCode(coll[0]);
			if (code == ResponseCodes.CODE_INVALID)
			{
				string msg = "Unable to process results Sites Request. Returned Data: " + coll[0];
				Exception ex = new Exception(msg, null);
				throw ex;
			}

			switch (code)
			{
				case ResponseCodes.CODE_500:
					return ResponseCodes.CODE_500;

				case ResponseCodes.CODE_401:
					return ResponseCodes.CODE_401;

				case ResponseCodes.CODE_210:
					{
						coll.RemoveAt(0);
						sites = new SiteCollection();
						foreach (String line in coll)
						{
							Debug.WriteLine("line: " + line);
							Site site = new Site(line);
							if (protocol == Site.PROTOCOLS.ALL)
								sites.Add(new Site(line));
							else if (site.Protocol == protocol)
								sites.Add(new Site(line));
						}

						return ResponseCodes.CODE_210;
					}

				default:
					return ResponseCodes.CODE_500;
			}

		}
		/// <overloads>
		/// Adds a range of elements to the end of the <see cref="SiteCollection"/>.
		/// </overloads>
		/// <summary>
		/// Adds the elements of another collection to the end of the <see cref="SiteCollection"/>.
		/// </summary>
		/// <param name="collection">The <see cref="SiteCollection"/> whose elements
		/// should be added to the end of the current collection.</param>
		/// <exception cref="ArgumentNullException">
		/// <paramref name="collection"/> is a null reference.</exception>
		/// <exception cref="NotSupportedException">
		/// <para>The <see cref="SiteCollection"/> is read-only.</para>
		/// <para>-or-</para>
		/// <para>The <b>SiteCollection</b> has a fixed size.</para>
		/// <para>-or-</para>
		/// <para>The <b>SiteCollection</b> already contains one or more elements
		/// in the specified <paramref name="collection"/>, and the <b>SiteCollection</b>
		/// ensures that all elements are unique.</para></exception>
		/// <remarks>Please refer to <see cref="ArrayList.AddRange"/> for details.</remarks>

		public virtual void AddRange(SiteCollection collection)
		{
			if (collection == null)
				throw new ArgumentNullException("collection");

			if (collection.Count == 0) return;
			if (this._count + collection.Count > this._array.Length)
				EnsureCapacity(this._count + collection.Count);

			++this._version;
			Array.Copy(collection.InnerArray, 0,
				this._array, this._count, collection.Count);
			this._count += collection.Count;
		}
		/// <summary>
		/// Creates a shallow copy of the <see cref="SiteCollection"/>.
		/// </summary>
		/// <returns>A shallow copy of the <see cref="SiteCollection"/>.</returns>
		/// <remarks>Please refer to <see cref="ArrayList.Clone"/> for details.</remarks>

		public virtual object Clone()
		{
			SiteCollection collection = new SiteCollection(this._count);

			Array.Copy(this._array, 0, collection._array, 0, this._count);
			collection._count = this._count;
			collection._version = this._version;

			return collection;
		}
			public override void AddRange(SiteCollection collection)
			{
				foreach (Site value in collection)
					CheckUnique(value);

				this._collection.AddRange(collection);
			}
		/// <summary>
		/// Initializes a new instance of the <see cref="SiteCollection"/> class
		/// that contains elements copied from the specified collection and
		/// that has the same initial capacity as the number of elements copied.
		/// </summary>
		/// <param name="collection">The <see cref="SiteCollection"/>
		/// whose elements are copied to the new collection.</param>
		/// <exception cref="ArgumentNullException">
		/// <paramref name="collection"/> is a null reference.</exception>
		/// <remarks>Please refer to <see cref="ArrayList(ICollection)"/> for details.</remarks>

		public SiteCollection(SiteCollection collection)
		{
			if (collection == null)
				throw new ArgumentNullException("collection");

			this._array = new Site[collection.Count];
			AddRange(collection);
		}
			public override void AddRange(SiteCollection collection)
			{
				lock (this._root) this._collection.AddRange(collection);
			}
			internal UniqueList(SiteCollection collection)
				:
				base(Tag.Default)
			{
				this._collection = collection;
			}
			public override void AddRange(SiteCollection collection)
			{
				throw new NotSupportedException(
					"Read-only collections cannot be modified.");
			}
			internal SyncList(SiteCollection collection)
				:
				base(Tag.Default)
			{

				this._root = collection.SyncRoot;
				this._collection = collection;
			}
			internal ReadOnlyList(SiteCollection collection)
				:
				base(Tag.Default)
			{
				this._collection = collection;
			}
			internal Enumerator(SiteCollection collection)
			{
				this._collection = collection;
				this._version = collection._version;
				this._index = -1;
			}
		/// <summary>
		/// Returns a wrapper for the specified <see cref="SiteCollection"/>
		/// ensuring that all elements are unique.
		/// </summary>
		/// <param name="collection">The <see cref="SiteCollection"/> to wrap.</param>    
		/// <returns>
		/// A wrapper around <paramref name="collection"/> ensuring that all elements are unique.
		/// </returns>
		/// <exception cref="ArgumentException">
		/// <paramref name="collection"/> contains duplicate elements.</exception>
		/// <exception cref="ArgumentNullException">
		/// <paramref name="collection"/> is a null reference.</exception>
		/// <remarks><para>
		/// The <b>Unique</b> wrapper provides a set-like collection by ensuring
		/// that all elements in the <see cref="SiteCollection"/> are unique.
		/// </para><para>
		/// <b>Unique</b> raises an <see cref="ArgumentException"/> if the specified 
		/// <paramref name="collection"/> contains any duplicate elements. The returned
		/// wrapper raises a <see cref="NotSupportedException"/> whenever the user attempts 
		/// to add an element that is already contained in the <b>SiteCollection</b>.
		/// </para><para>
		/// <strong>Note:</strong> The <b>Unique</b> wrapper reflects any changes made
		/// to the underlying <paramref name="collection"/>, including the possible
		/// creation of duplicate elements. The uniqueness of all elements is therefore
		/// no longer assured if the underlying collection is manipulated directly.
		/// </para></remarks>

		public static SiteCollection Unique(SiteCollection collection)
		{
			if (collection == null)
				throw new ArgumentNullException("collection");

			for (int i = collection.Count - 1; i > 0; i--)
				if (collection.IndexOf(collection[i]) < i)
					throw new ArgumentException("collection",
						"Argument cannot contain duplicate elements.");

			return new UniqueList(collection);
		}
		/// <summary>
		/// Returns a synchronized (thread-safe) wrapper
		/// for the specified <see cref="SiteCollection"/>.
		/// </summary>
		/// <param name="collection">The <see cref="SiteCollection"/> to synchronize.</param>
		/// <returns>
		/// A synchronized (thread-safe) wrapper around <paramref name="collection"/>.
		/// </returns>
		/// <exception cref="ArgumentNullException">
		/// <paramref name="collection"/> is a null reference.</exception>
		/// <remarks>Please refer to <see cref="ArrayList.Synchronized"/> for details.</remarks>

		public static SiteCollection Synchronized(SiteCollection collection)
		{
			if (collection == null)
				throw new ArgumentNullException("collection");

			return new SyncList(collection);
		}
		/// <summary>
		/// Returns a read-only wrapper for the specified <see cref="SiteCollection"/>.
		/// </summary>
		/// <param name="collection">The <see cref="SiteCollection"/> to wrap.</param>
		/// <returns>A read-only wrapper around <paramref name="collection"/>.</returns>
		/// <exception cref="ArgumentNullException">
		/// <paramref name="collection"/> is a null reference.</exception>
		/// <remarks>Please refer to <see cref="ArrayList.ReadOnly"/> for details.</remarks>

		public static SiteCollection ReadOnly(SiteCollection collection)
		{
			if (collection == null)
				throw new ArgumentNullException("collection");

			return new ReadOnlyList(collection);
		}