using System;
using System.Collections.Generic;
using System.Text;
using System.Net.Sockets;
using System.Threading;

using Rebex.Net;
using Rebex.Security;
using Rebex.Security.Certificates;

namespace TlsTestApp
{
    class Program
    {
        public class MyCertVerifier : ICertificateVerifier
        {
            public TlsCertificateAcceptance Verify(TlsSocket socket, string commonName, CertificateChain certificateChain)
            {
                Console.WriteLine("---------------------- CERT VERIFIER ----------------------");
                Console.WriteLine("CN: " + commonName);
                Console.WriteLine("Chain cnt: " + certificateChain.Count);
                Console.WriteLine("VALIDATION RESULT: " + certificateChain.Validate(commonName, ValidationOptions.AllowUnknownCa).Valid);
                Console.WriteLine("VALIDATION STATUS: " + certificateChain.Validate(commonName, ValidationOptions.AllowUnknownCa).Status);

                for(int i = 0; i < certificateChain.Count; i++)
                    Console.WriteLine("* Chain " + i + ": " + certificateChain[i].GetCommonName());
                Console.WriteLine("---------------------- END VERIFIER ----------------------");

                return TlsCertificateAcceptance.Accept;
            }
        }

        private static byte[] recvBuffer = new byte[4096];

        static void AsyncRecv(IAsyncResult ar)
        {
            Console.Write("RECV:");

            try
            {
                TlsSocket s = (TlsSocket)ar.AsyncState;
                int bytesRecv = s.EndReceive(ar);

                if (bytesRecv == 0)
                    throw new Exception("end of stream");

                Console.Write(Encoding.ASCII.GetString(recvBuffer, 0, bytesRecv));

                // Receive more
                s.BeginReceive(recvBuffer, 0, recvBuffer.Length, SocketFlags.None, new AsyncCallback(AsyncRecv), s);
            }
            catch (Exception ex)
            {
                Console.Error.WriteLine("Error AsyncRecv: " + ex.Message);
            }
        }

        static void Main(string[] args)
        {
            try
            {
                String hostName = "www.digicert.com";

                TlsParameters tlsPar = new TlsParameters();
                tlsPar.AllowedSuites = TlsCipherSuite.Secure; // Only secure encryption allowed
                tlsPar.CertificateVerifier = new MyCertVerifier();
                tlsPar.Entity = TlsConnectionEnd.Client;
                tlsPar.Version = TlsVersion.TLS10;
                tlsPar.CommonName = hostName;

                Console.WriteLine("* Connecting to https://" + hostName);
                TlsSocket secureSocket = new TlsSocket(AddressFamily.InterNetwork);
                secureSocket.Parameters = tlsPar;
                secureSocket.Connect(hostName, 443);
                secureSocket.Negotiate(); // Enable SSL/TLS

                Console.WriteLine("* Connected successfully at " + DateTime.Now);

                Console.WriteLine("CipherAlgorithm: " + secureSocket.Cipher.CipherAlgorithm);
                Console.WriteLine("EffectiveKeySize: " + secureSocket.Cipher.EffectiveKeySize);
                Console.WriteLine("KeyExchangeAlgorithm: " + secureSocket.Cipher.KeyExchangeAlgorithm);
                Console.WriteLine("KeySize: " + secureSocket.Cipher.KeySize);
                Console.WriteLine("Protocol: " + secureSocket.Cipher.Protocol);
                Console.WriteLine("Suite ID: " + secureSocket.Cipher.Suite);

                // HTTP req
                string request = "GET / HTTP/1.0\r\n" +
                    "Accept: */*\r\n" +
                    "User-Agent: SecureSocket Component\r\n" +
                    "Host: " + hostName + "\r\n" +
                    "\r\n";

                byte[] b = Encoding.ASCII.GetBytes(request);
                secureSocket.Send(b);

                Console.WriteLine("--------------- WAITING FOR RESPONSE ---------------");

                //////// Async
                secureSocket.BeginReceive(recvBuffer, 0, recvBuffer.Length, SocketFlags.None,
                    new AsyncCallback(AsyncRecv), secureSocket);

                Thread.Sleep(10000);
                //////// END async

                //////// Synchronous - works!
                //Console.Write("RECV:");
                //int bytesReceived;
                //do
                //{
                //    bytesReceived = secureSocket.Receive(recvBuffer, SocketFlags.None);
                //    Console.Write(Encoding.ASCII.GetString(recvBuffer, 0, bytesReceived));
                //} while (bytesReceived > 0);
                //////// END synchronous

                try
                {
                    Console.WriteLine("\nShutting down after 10 sec");
                    secureSocket.Shutdown(SocketShutdown.Both);
                }
                catch (Exception)
                {
                }

                secureSocket.Close();
            }
            catch (Exception ex)
            {
                Console.WriteLine("ERROR: " + ex.Message);
                Console.WriteLine(ex.StackTrace);
            }
        }
    }
}