//
// EndPointManager.cs
//	Copied from System.Net.EndPointManager.cs
//
// Author:
//	Gonzalo Paniagua Javier (gonzalo@ximian.com)
//
// Copyright (c) 2005 Novell, Inc. (http://www.novell.com)
// Copyright (c) 2012-2013 sta.blockhead
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
// 
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

using System;
using System.Collections;
using System.Collections.Generic;
using System.Net;

namespace WebSocketSharp.Net
{
	internal sealed class EndPointManager
	{
		#region Private Fields

		private static Dictionary<IPAddress, Dictionary<int, EndPointListener>> _ipToEndpoints = new Dictionary<IPAddress, Dictionary<int, EndPointListener>> ();

		#endregion

		#region Private Constructors

		private EndPointManager ()
		{
		}

		#endregion

		#region Private Methods

		private static void addPrefix (string uriPrefix, HttpListener httpListener)
		{
			var prefix = new ListenerPrefix (uriPrefix);
			if (prefix.Path.IndexOf ('%') != -1)
				throw new HttpListenerException (400, "Invalid path.");

			if (prefix.Path.IndexOf ("//", StringComparison.Ordinal) != -1) // TODO: Code?
				throw new HttpListenerException (400, "Invalid path.");

			// Always listens on all the interfaces, no matter the host name/ip used.
			var epListener = getEndPointListener (IPAddress.Any, prefix.Port, httpListener, prefix.Secure);
			epListener.AddPrefix (prefix, httpListener);
		}

		private static EndPointListener getEndPointListener (
			IPAddress address, int port, HttpListener httpListener, bool secure)
		{
			Dictionary<int, EndPointListener> endpoints = null;
			if (_ipToEndpoints.ContainsKey (address))
			{
				endpoints = _ipToEndpoints [address];
			}
			else
			{
				endpoints = new Dictionary<int, EndPointListener> ();
				_ipToEndpoints [address] = endpoints;
			}

			EndPointListener epListener = null;
			if (endpoints.ContainsKey (port))
			{
				epListener = endpoints [port];
			}
			else
			{
				epListener = new EndPointListener (
					address, port, secure, httpListener.CertificateFolderPath, httpListener.DefaultCertificate);
				endpoints [port] = epListener;
			}

			return epListener;
		}

		private static void removePrefix (string uriPrefix, HttpListener httpListener)
		{
			var prefix = new ListenerPrefix (uriPrefix);
			if (prefix.Path.IndexOf ('%') != -1)
				return;

			if (prefix.Path.IndexOf ("//", StringComparison.Ordinal) != -1)
				return;

			var epListener = getEndPointListener (IPAddress.Any, prefix.Port, httpListener, prefix.Secure);
			epListener.RemovePrefix (prefix, httpListener);
		}

		#endregion

		#region Public Methods

		public static void AddListener (HttpListener httpListener)
		{
			var added = new List<string> ();
			lock (((ICollection) _ipToEndpoints).SyncRoot)
			{
				try {
					foreach (var prefix in httpListener.Prefixes)
					{
						addPrefix (prefix, httpListener);
						added.Add (prefix);
					}
				}
				catch {
					foreach (var prefix in added)
						removePrefix (prefix, httpListener);

					throw;
				}
			}
		}

		public static void AddPrefix (string uriPrefix, HttpListener httpListener)
		{
			lock (((ICollection) _ipToEndpoints).SyncRoot)
			{
				addPrefix (uriPrefix, httpListener);
			}
		}

		public static void RemoveEndPoint (EndPointListener epListener, IPEndPoint endpoint)
		{
			lock (((ICollection) _ipToEndpoints).SyncRoot)
			{
				var endpoints = _ipToEndpoints [endpoint.Address];
				endpoints.Remove (endpoint.Port);
				if (endpoints.Count == 0)
					_ipToEndpoints.Remove (endpoint.Address);

				epListener.Close ();
			}
		}

		public static void RemoveListener (HttpListener httpListener)
		{
			lock (((ICollection) _ipToEndpoints).SyncRoot)
			{
				foreach (var prefix in httpListener.Prefixes)
					removePrefix (prefix, httpListener);
			}
		}

		public static void RemovePrefix (string uriPrefix, HttpListener httpListener)
		{
			lock (((ICollection) _ipToEndpoints).SyncRoot)
			{
				removePrefix (uriPrefix, httpListener);
			}
		}

		#endregion
	}
}