using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Text.RegularExpressions;
using System.Text;
using System.Threading;
using System.Diagnostics;
using System;
using System.Xml;

namespace RavelNetworking
{
    static public class Upnp
    {
        static string xmlURL = "";
        static string RouterIP = "";
        static string insertIP ="";
        static string Port = "";
        static string productName = "";
        static bool Gateway;
        static List<string> maplayout;
        static List<string> ServiceTypes = new List<string>();
        static List<string> ControlTypes = new List<string>();

        public static void Discover(int port, NetSocket socket)
        {
            insertIP = GetIP();
            Port = port.ToString();

            Thread thd = new Thread(Response);
            thd.Start();
        }

        static string GetIP()
        {
            var host = Dns.GetHostEntry(Dns.GetHostName());
            foreach (var ip in host.AddressList)
            {
                if (ip.AddressFamily == AddressFamily.InterNetwork)
                {
                    return ip.ToString();
                }
                throw new Exception("No network adapters with an IPv4 address in the system!");
            }

            return "";
        }

        static void Response()
        {
            bool finished = false;

            Stopwatch sw = new Stopwatch ();
            sw.Start ();
            string[] foundDevices = new string[200];
            int deviceCount = 0;

            var ssdpMsg = "M-SEARCH * HTTP/1.1\r\nHOST:239.255.255.250:1900\r\nMAN:\"ssdp:discover\"\r\nST:ssdp:all\r\nMX:5\r\n\r\n";
            var ssdpPacket = Encoding.ASCII.GetBytes(ssdpMsg);
            IPAddress multicastAddress = IPAddress.Parse ("239.255.255.250");
            var socket = new Socket (AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);

            socket.Bind(new IPEndPoint(IPAddress.Any, 0));
            socket.SetSocketOption(SocketOptionLevel.IP, SocketOptionName.AddMembership, new MulticastOption(multicastAddress, IPAddress.Any));
            socket.SendTo(ssdpPacket,SocketFlags.None, new IPEndPoint(multicastAddress, 1900));
            var response = new byte[8000];
            EndPoint ep = new IPEndPoint(IPAddress.Any, 0);
            socket.Blocking = false;

            while (!finished)
            {
                try
                {
                    socket.ReceiveFrom(response, ref ep);
                    var str = Encoding.UTF8.GetString(response);
                    var aSTR = str.Split ('\n');
                    foreach (string i in aSTR)
                    {

                        if(i.IndexOf (("SERVER: "),StringComparison.CurrentCultureIgnoreCase) != -1)
                        {
                            string newDev = i.Replace ("Server: ","");
                            if(!foundDevices.Contains (newDev))
                            {
                                foundDevices[deviceCount] = newDev;
                                deviceCount++;
                            }
                        }

                        if(i.IndexOf (("LOCATION: "),StringComparison.CurrentCultureIgnoreCase) != -1)
                        {
                            xmlURL = Regex.Replace(i, "Location: ", "", RegexOptions.IgnoreCase);
                            RouterIP = GetBetween (i,"http://","/");
                        }

                        if(i.IndexOf (("InternetGatewayDevice"),StringComparison.CurrentCultureIgnoreCase) != -1)
                        {
                            Gateway = true;
                        }


                        if(Gateway)
                        {
                            WebClient webClient = new WebClient();
                            string routerXML = webClient.DownloadString(xmlURL);

                            if(routerXML.Contains ("urn:schemas-upnp-org:service:WANIPConnection:0"))
                                ServiceTypes.Add ("urn:schemas-upnp-org:service:WANIPConnection:0");

                            if(routerXML.Contains ("urn:schemas-upnp-org:service:WANIPConnection:1"))
                                ServiceTypes.Add ("urn:schemas-upnp-org:service:WANIPConnection:1");

                            if(routerXML.Contains ("urn:schemas-upnp-org:service:WANPPPConnection:0"))
                                ServiceTypes.Add ("urn:schemas-upnp-org:service:WANPPPConnection:0");

                            if(routerXML.Contains ("urn:schemas-upnp-org:service:WANPPPConnection:1"))
                                ServiceTypes.Add ("urn:schemas-upnp-org:service:WANPPPConnection:1");

                            if(ServiceTypes.Count == 0)
                            {
                                socket.Close();
                                finished = true;
                            }

                            foreach(string svcType in ServiceTypes)
                            {
                                int strIndex = routerXML.IndexOf (svcType);
                                string ctrlType = GetBetween(routerXML.Substring (strIndex),"<controlURL>","</controlURL>");
                                ControlTypes.Add (ctrlType);
                            }

                            webClient.Dispose ();
                            socket.Shutdown(SocketShutdown.Both);
                            GetMappings();
                            finished = true;
                        }
                    }
                }catch{}
            }
        }

        static void GetMappings()
        {
            for(int s = 0; s < ServiceTypes.Count; s++)
            {
                maplayout = new List<string> ();
                string xmlresponse = "";
                int i = 0;
                int dex = 0;
                switch (i)
                {

                case 0:
                    var soapBody =
                        "<s:Envelope xmlns:s=\"http://schemas.xmlsoap.org/soap/envelope/\" s:encodingStyle=\"http://schemas.xmlsoap.org/soap/encoding/\"><s:Body><u:"
                            + "GetGenericPortMappingEntry"
                            + "xmlns:u=\"" + ServiceTypes[s] + "\">"
                            + "<NewPortMappingIndex>"+dex.ToString ()+"</NewPortMappingIndex>"
                            + "<NewRemoteHost></NewRemoteHost>"
                            + "<NewExternalPort></NewExternalPort>"
                            + "<NewProtocol></NewProtocol>"
                            + "<NewInternalPort></NewInternalPort>"
                            + "<NewInternalClient></NewInternalClient>"
                            + "<NewEnabled>1</NewEnabled>"
                            + "<NewPortMappingDescription></NewPortMappingDescription>"
                            + "<NewLeaseDuration></NewLeaseDuration>"
                            + "</u:GetGenericPortMappingEntry></s:Body></s:Body></s:Envelope>\r\n\r\n";

                    byte[] body = System.Text.UTF8Encoding.ASCII.GetBytes (soapBody);
                    var url = "http://" + RouterIP + ControlTypes[s];

                    try
                    {
                        var wr = HttpWebRequest.Create (url);
                        wr.Method = "POST";
                        wr.Headers.Add ("SOAPAction", "\"" + ServiceTypes[s] + "#GetGenericPortMappingEntry" + "\"");
                        wr.ContentType = "text/xml;charset=\"utf-8\"";
                        wr.ContentLength = body.Length;
                        var stream = wr.GetRequestStream ();
                        stream.Write (body, 0, body.Length);
                        stream.Flush ();
                        stream.Close ();

                        using (HttpWebResponse response = (HttpWebResponse)wr.GetResponse()) {
                            Stream receiveStream = response.GetResponseStream ();
                            StreamReader readStream = new StreamReader (receiveStream, Encoding.UTF8);
                            xmlresponse = readStream.ReadToEnd ();
                            response.Close ();
                            readStream.Close ();
                        }
                    } catch{
                        goto case 2;
                    }
                    goto case 1;

                case 1:
                    string thisip = GetBetween (xmlresponse, "<NewInternalClient>", "</NewInternalClient>");
                    string thisport = GetBetween (xmlresponse,"<NewInternalPort>", "</NewInternalPort>");
                    string thisprod = GetBetween (xmlresponse,"<NewPortMappingDescription>","</NewPortMappingDescription>");

                    if(thisip == insertIP && thisprod == productName)
                        break;

                    dex++;
                    maplayout.Add (thisport);
                    goto case 0;

                case 2:
                    for(int p = int.Parse (Port); p < ushort.MaxValue;p++)
                    {
                        if(!maplayout.Contains (p.ToString ()))
                        {
                            Port = p.ToString ();
                            SetPort (s);
                            break;
                        }
                    }
                    break;
                }
            }
        }

        static void SetPort(int count)
        {
            string portType = "UDP";

            var soapBody =
            "<s:Envelope xmlns:s=\"http://schemas.xmlsoap.org/soap/envelope/\" s:encodingStyle=\"http://schemas.xmlsoap.org/soap/encoding/\"><s:Body><u:"
                    + "AddPortMapping"
                    + " xmlns:u=\"" + ServiceTypes[count] + "\">"
                    + "<NewRemoteHost></NewRemoteHost>"
                    + "<NewExternalPort>" + Port + "</NewExternalPort>"
                    + "<NewProtocol>"+portType+"</NewProtocol>"
                    + "<NewInternalPort>" + Port + "</NewInternalPort>"
                    + "<NewInternalClient>" + insertIP + "</NewInternalClient>"
                    + "<NewEnabled>1</NewEnabled>"
                    + "<NewPortMappingDescription>" + productName + "</NewPortMappingDescription>"
                    + "<NewLeaseDuration>0</NewLeaseDuration>"
                    + "</u:AddPortMapping></s:Body></s:Body></s:Envelope>\r\n\r\n";

            byte[] body = System.Text.UTF8Encoding.ASCII.GetBytes(soapBody);
            var url = "http://" + RouterIP+ControlTypes[count];
            var wr = HttpWebRequest.Create(url);
            wr.Method = "POST";
            wr.Headers.Add("SOAPAction","\""+ServiceTypes[count]+"#"+"AddPortMapping"+"\"");
            wr.ContentType = "text/xml;charset=\"utf-8\"";
            wr.ContentLength = body.Length;
            var stream = wr.GetRequestStream();
            stream.Write(body, 0, body.Length);
            stream.Flush();
            stream.Close();
        }

        static string GetBetween(string strSource, string strStart, string strEnd)
        {
            int Start, End;
            Start = strSource.IndexOf(strStart, 0) + strStart.Length;
            End = strSource.IndexOf(strEnd, Start);
            return strSource.Substring(Start, End - Start);
        }
    }
}