//
//  Class:			TelnetDataHandler
//	Current CLR:	4.0.30319.296
//	System:			Microsoft Visual Studio 10.0
//	Author:			dani
// 	Created:		3/16/2013 2:12:35 PM
//
//	Copyright (c) 2013 Informatikbüro Daniel Schick. All rights reserved.

using System;
using System.Collections.Generic;
using System.Threading;
using System.Diagnostics;

using log4net;

namespace bsmd.AISService.AIS
{
    public class TelnetDataHandler
    {
        AIS_Telnet aisTelnet;
        AIS_Decoder decoder;
        Thread readerThread;
        bool requestStop;

        internal static ILog _log = LogManager.GetLogger(typeof(TelnetDataHandler));

        public TelnetDataHandler(AIS_Telnet telnetConnection, AIS_Decoder aisDecoder)
        {
            this.aisTelnet = telnetConnection;
            this.decoder = aisDecoder;
        }

        public AIS_Decoder AIS_Decoder
        {
            get { return this.decoder; }
        }

        public override string ToString()
        {
            return string.Format("Telnet AIS Receiver {0}:{1}",
                this.aisTelnet.Hostname,
                this.aisTelnet.Port);
        }

        public bool Start(ref string message)
        {
            if (readerThread != null) return true; // already running
            try
            {
                this.readerThread = new Thread(new ThreadStart(this.ReaderThread));
                readerThread.Start();
                this.requestStop = false;
                message = "reader thread started";
                return true;
            }
            catch (Exception ex)
            {
                message = ex.Message;
                return false;
            }
        }

        public void Stop()
        {
            if (readerThread.IsAlive)
            {
                this.requestStop = true;
                readerThread.Join();
            }
            this.readerThread = null;
        }

        private void ReaderThread()
        {
            NMEA.Status nmea_Status = NMEA.Status.OK;
            _log.Info("starting telnet reader thread");
            while (!requestStop)
            {
                try
                {

                    string data = this.aisTelnet.ReadLine();
                    // Trace.WriteLine(data);
                    if (data != null && data.Length > 0)
                    {
                        NMEA decodedSentence = NMEA.Decode(data, ref nmea_Status);
                        if (decodedSentence != null)
                        {
                            if (decodedSentence is NMEA_AIS_Sentence)
                            {
                                NMEA_AIS_Sentence aisSentence = decodedSentence as NMEA_AIS_Sentence;
                                this.decoder.Decode(aisSentence.AIS_Message, aisSentence.Msg_Sentence_Nr,
                                    aisSentence.Total_Sentence_Nr, aisSentence.Seq_Message_Ident, this.aisTelnet.StationName);
                            }
                        }
                        else
                        {
                            _log.Info("Serial data handler: NMEA decoder returned null/empty sentence");
                        }
                    }
                }
                catch (Exception ex)
                {
                    var st = new StackTrace(ex, true);
                    var frame = st.GetFrame(0);
                    var line = frame.GetFileLineNumber();
                    _log.WarnFormat("Exception in telnet reader thread: {0}, top frame ln {1}", ex.Message, line);                    
                }
                // Thread.Sleep(100);
            }
            aisTelnet.Close();
        }
    }
}