namespace Server
{
    public partial class Service1 : ServiceBase
    {
        private readonly log4net.ILog log = log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);
        string flagFile = @"D:FlagFile\flag.txt";
        byte[] b1;// Buffer for reading data
        int bytesNum = 20;//Number of byts to readwrite since it's a flag.txt file we don't need too much byts
        TcpListener server;
        TcpClient client;
        const int PORT = 8100; //Set the selected port
        IPAddress localAddr = IPAddress.Parse("127.0.0.1");
        Thread incomingConnection, fileCheck;

        public Service1()
        {
            InitializeComponent();
        }

        protected override void OnStart(string[] args)
        {
            server = new TcpListener(localAddr, PORT);
            // Start listening for client requests.
            server.Start();
            log.Info("Server logged in");
            //This thread should go every X time to check if flag.txt and to delete it if exists
            fileCheck = new Thread(fileChecker);
            fileCheck.Start();
            incomingConnection = new Thread(inConnection);
            incomingConnection.Start();
        }

        private void inConnection()
        {
            //Always listen for client
            while (true)
            {
                client = server.AcceptTcpClient();
                Stream s = client.GetStream();
                b1 = new byte[bytesNum];
                s.Read(b1, 0, b1.Length);
                log.Info("Server received file: ");
                File.WriteAllBytes(flagFile, b1);                                                                                                                //server.Stop();                                                                                                                                 // client.Close();
            }
        }

        //Sparete thread, his job is to alaways check the target folder
        public void fileChecker()
        {
            while (true)
            {
                Thread.Sleep(20000);
                if (File.Exists(flagFile))
                {
                    File.Delete(flagFile);
                    log.Info("Server deleted the flag file: ");
                }
                else
                {
                    log.Warn("The file hasn't reached for a while!!!: ");
                    //Send email and report the problem
                    sendMail();
                    break;
                }
            }
        }

        private void sendMail()
        {
            SmtpClient client = new SmtpClient("smtp.gmail.com", 587);
            client.EnableSsl = true;
            client.Timeout = 10000;
            client.DeliveryMethod = SmtpDeliveryMethod.Network;
            client.UseDefaultCredentials = false;
            client.Credentials = new NetworkCredential("examplename20@gmail.com", "examplename2099");
            MailMessage msg = new MailMessage();
            msg.To.Add("nehoraielbaz@gmail.com");
            msg.From = new MailAddress("examplename20@gmail.com");
            msg.Subject = "Flag file error";
            msg.Body = "Flag file hasn't reached for a while.";
            client.Send(msg);
            log.Info("Email sent to report the problem");
        }

        protected override void OnStop()
        {
            log.Info("Server logged out");
            if (client != null)
            {
                client.GetStream().Close();
                client.Close();
                server.Stop();
            }
            incomingConnection.Abort();
            fileCheck.Abort();
            Environment.Exit(0);
        }
    }
}