/*
 * Copyright (c) Contributors, http://opensimulator.org/
 * See CONTRIBUTORS.TXT for a full list of copyright holders.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the OpenSimulator Project nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

using System.Collections.Generic;
using System.Net;
using OpenSim.Framework;
using OpenSim.Region.Framework.Scenes;

namespace OpenSim.Region.CoreModules.Agent.IPBan
{
    internal class SceneBanner
    {
        private static readonly log4net.ILog m_log
                    = log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);

        private List<string> bans;
        // private SceneBase m_scene;
        public SceneBanner(SceneBase scene, List<string> banList)
        {
            scene.EventManager.OnNewClient += EventManager_OnClientConnect;

            bans = banList;
            // m_scene = scene;
        }

        void EventManager_OnClientConnect(IClientAPI client)
        {
            // Only need to run through all this if there are entries in the ban list
            if (bans.Count > 0)
            {
                IPAddress end = client.RemoteEndPoint.Address;
                string endstr = end.ToString();
                string hostName = null;
                try
                {
                    IPHostEntry rDNS = Dns.GetHostEntry(end);
                    hostName = rDNS.HostName;
                }
                catch (System.Net.Sockets.SocketException)
                {
                    //m_log.WarnFormat("[IPBAN] IP address \"{0}\" cannot be resolved via DNS", end);
                    hostName = null;
                }

                if(string.IsNullOrEmpty(hostName))
                {
                    // just try possible ip match
                    foreach (string ban in bans)
                    {
                        if (endstr.StartsWith(ban))
                        {
                            client.Disconnect("Banned - network \"" + ban + "\" is not allowed to connect to this server.");
                            m_log.Warn("[IPBAN] Disconnected '" + end + "' due to '" + ban + "' ban.");
                            return;
                        }
                    }
                }
                else
                {
                    foreach (string ban in bans)
                    {
                        if (hostName.Contains(ban) || end.ToString().StartsWith(ban))
                        {
                            client.Disconnect("Banned - network \"" + ban + "\" is not allowed to connect to this server.");
                            m_log.Warn("[IPBAN] Disconnected '" + end + "' due to '" + ban + "' ban.");
                            return;
                        }
                    }
                }
            }
            // m_log.DebugFormat("[IPBAN] User \"{0}\" not in any ban lists. Allowing connection.", end);
        }
    }
}
