HexapiBackground.GpsExtensions.ParseNmea C# (CSharp) Method

        internal static LatLon ParseNmea(this string data)
        {
            try
            {
                var tokens = data.Split(',');
                var type = tokens[0];

                switch (type)
                {
                    case "GPGGA": //Global Positioning System Fix Data
                        if (tokens.Length < 10)
                            return null;

                        var st = tokens[1];

                        _dateTime = new DateTime(DateTime.Now.Year, DateTime.Now.Month, DateTime.Now.Day,
                            Convert.ToInt32(st.Substring(0, 2)), Convert.ToInt32(st.Substring(2, 2)),
                            Convert.ToInt32(st.Substring(4, 2)), DateTimeKind.Local);

                        _lat = Latitude2Double(tokens[2], tokens[3]);
                        _lon = Longitude2Double(tokens[4], tokens[5]);

                        int quality;
                        if (int.TryParse(tokens[6], out quality))
                            _quality = (GpsFixQuality)quality;

                        if (float.TryParse(tokens[9], out _altitude))
                            _altitude = _altitude * 3.28084f;

                        double.TryParse(tokens[8], out _hdop);

                        break;
                    case "GPGLL": //Global Positioning System Fix Data
                        if (tokens.Length < 8)
                            return null;

                        _lat = Latitude2Double(tokens[1], tokens[2]);
                        _lon = Longitude2Double(tokens[3], tokens[4]);

                        break;
                    case "GPRMC": //Recommended minimum specific GPS/Transit data

                        if (tokens.Length < 9)
                            return null;

                        _lat = Latitude2Double(tokens[3], tokens[4]);
                        _lon = Longitude2Double(tokens[5], tokens[6]);

                        double fps = 0;
                        if (double.TryParse(tokens[7], out fps))
                            _feetPerSecond = Math.Round(fps * 1.68781, 2); //Convert knots to feet per second or "Speed over ground"

                        double dir = 0;
                        if (double.TryParse(tokens[8], out dir))
                            _heading = dir; //angle from true north that you are traveling or "Course made good"

                        break;
                    case "GPGSV": //Satellites in View

                        if (tokens.Length < 8)
                            return null;

                        int satellitesInView;
                        if (int.TryParse(tokens[3], out satellitesInView))
                            _satellitesInView = satellitesInView;

                        int signalToNoiseRatio;
                        if (int.TryParse(tokens[7], out signalToNoiseRatio))
                            _signalToNoiseRatio = signalToNoiseRatio;

                        break;
                    case "PSTI":
                        if (!tokens[1].Equals("030") || tokens.Length < 15)
                            break;

                        //tokens[12] 
                        //                        Mode indicator
                        //‘N’ = Data not valid 
                        //‘A’ = Autonomous mode
                        //‘D’ = Differential mode
                        //‘E’ = Estimated(dead reckoning) mode
                        //‘M’ = Manual input mode 
                        //‘S’ = Simulator mode
                        //‘F’ = Float RTK.Satellite syst
                        //em used in RTK mode, floating
                        //integers
                        //‘R’ = Real Time Kinematic. System used in RTK mode with fixed
                        //integers

                        double.TryParse(tokens[13], out _rtkAge);
                        double.TryParse(tokens[14], out _rtkRatio);

                        break;
                    default:
                        return null;
                }

                if (Math.Abs(_lat) < .1 || Math.Abs(_lon) < .1)
                    return null;
            }
            catch (ArgumentOutOfRangeException)
            {
                //No fix yet
            }
            catch (IndexOutOfRangeException)
            {
                //No fix yet
            }
            catch (Exception e)
            {
                if (_quality != GpsFixQuality.NoFix)
                {
                    Debug.WriteLine(e);
                    Debug.WriteLine(data);
                }
            }

            var latLon = new LatLon
            {
                Lat = _lat,
                Lon = _lon,
                Altitude = _altitude,
                FeetPerSecond = _feetPerSecond,
                Quality = _quality,
                SatellitesInView = _satellitesInView,
                SignalToNoiseRatio = _signalToNoiseRatio,
                Heading = _heading,
                DateTime = _dateTime,
                RtkAge = _rtkAge,
                RtkRatio = _rtkRatio,
                Hdop = _hdop
            };

            //if (_quality > GpsFixQuality.NoFix)
            //    Debug.WriteLine($"Lat, Lon : {_lat}, {_lon}, {_quality}, Heading {_heading}, Alt {_altitude}, Sats {_satellitesInView}, SignalToNoise {_signalToNoiseRatio}");

            return latLon;
        }
    }