//parses the lat and long to a decimal format from DDMM.MMM format
//conversion method in the Mapping class
private GPSPacket latLongConvertToDbl(GPSPacket updatedGpsDataForLatLong)
{
Mapping mapObjectTemp = new Mapping(); //used just for the lat/long parsing method
mapObjectTemp.parseLatLong(updatedGpsDataForLatLong.latitude, updatedGpsDataForLatLong.longitude, false);
updatedGpsDataForLatLong.latitude = mapObjectTemp.latitudeD.ToString();
updatedGpsDataForLatLong.longitude = mapObjectTemp.longitudeD.ToString();
return(updatedGpsDataForLatLong);
}
//-------------------END NEW PARSING METHODS-------------------------
//Make sure the checksum is correct by generating a checksum from the string and comparing
public GPSPacket getChecksum(string sentence, GPSPacket updatedGpsData, int sentenceType)
{
string checksum = "", checksumStr = "";
//Start with first Item
int checksumCalc = Convert.ToByte(sentence[sentence.IndexOf('$') + 1]);
// Loop through all chars to get a checksum
for (int i = sentence.IndexOf('$') + 2; i < sentence.IndexOf('*'); i++)
{
// No. XOR the checksum with this character's value
checksumCalc ^= Convert.ToByte(sentence[i]);
}
//convert the integer value to a 2-digit hex (in string representation)
checksumStr = checksumCalc.ToString("X2");
switch (sentenceType)
{
//case 0 = GPRMC
case 0: checksum = checksumGNRMC; break;
case 1: checksum = checksumGNGGA; break;
case 2: checksum = checksumGNVTG; break;
default:
break;
}
// Check what was parsed from the NMEA string and compare to the raw calculation
if (checksumStr == checksum)
{
//checksum passed, return object
return(updatedGpsData);
}
else
{
//the checksum has failed, note that in the field
switch (sentenceType)
{
//case 0 = GPRMC
case 0: checksumGNRMC = "FAIL"; break;
//case 1 = GPGGA
case 1: checksumGNGGA = "FAIL"; break;
//case 2 = GTVTG
case 2: checksumGNVTG = "FAIL"; break;
default:
break;
}
return(updatedGpsData);
}
}
private GPSPacket trackToCardinal(GPSPacket updatedGpsData)
{
//each degree direction corresponds to some cardinal direction
//first convert trkangle to a double to evaluate it
double trkAngle_double;
bool result = Double.TryParse(updatedGpsData.trkangle, System.Globalization.NumberStyles.Any, System.Globalization.CultureInfo.InvariantCulture, out trkAngle_double);
if (result == true)
{
if ((348.75 >= trkAngle_double && trkAngle_double <= 360) || ((0 >= trkAngle_double && trkAngle_double <= 33.75)))
{
updatedGpsData.cardAngle = "N";
}
else if ((33.75 > trkAngle_double && trkAngle_double <= 78.75))
{
updatedGpsData.cardAngle = "NE";
}
else if ((78.75 > trkAngle_double && trkAngle_double <= 101.25))
{
updatedGpsData.cardAngle = "E";
}
else if ((101.25 > trkAngle_double && trkAngle_double <= 168.75))
{
updatedGpsData.cardAngle = "SE";
}
else if ((168.75 > trkAngle_double && trkAngle_double <= 213.75))
{
updatedGpsData.cardAngle = "S";
}
else if ((213.75 > trkAngle_double && trkAngle_double <= 258.75))
{
updatedGpsData.cardAngle = "SW";
}
else if ((258.75 > trkAngle_double && trkAngle_double <= 303.75))
{
updatedGpsData.cardAngle = "W";
}
else if ((303.75 > trkAngle_double && trkAngle_double < 348.75))
{
updatedGpsData.cardAngle = "NW";
}
}
return(updatedGpsData);
}
public void populateDbFields(GPSPacket gpsDataForDB)
{
//create a document fragment that will be appended to the existing XML
XmlWriter addToDb = createXmlDbStructure();
addToDb.WriteStartElement("Packet"); //start packet
addToDb.WriteAttributeString("ID", gpsDataForDB.packetID.ToString());
addToDb.WriteElementString("Date", gpsDataForDB.date);
addToDb.WriteElementString("Time", gpsDataForDB.time);
addToDb.WriteElementString("Latitude", gpsDataForDB.latitude);
addToDb.WriteElementString("Longitude", gpsDataForDB.longitude);
addToDb.WriteStartElement("GroundSpeed");
addToDb.WriteAttributeString("Type", "knots");
addToDb.WriteValue(gpsDataForDB.grspd_k);
addToDb.WriteEndElement();
addToDb.WriteStartElement("GroundSpeed");
addToDb.WriteAttributeString("Type", "kph");
addToDb.WriteValue(gpsDataForDB.grspd_kph);
addToDb.WriteEndElement();
addToDb.WriteElementString("Altitude", gpsDataForDB.altitude);
addToDb.WriteStartElement("Angle");
addToDb.WriteAttributeString("Type", "Cardinal");
addToDb.WriteValue(gpsDataForDB.cardAngle);
addToDb.WriteEndElement();
addToDb.WriteStartElement("Angle");
addToDb.WriteAttributeString("Type", "Degrees");
addToDb.WriteValue(gpsDataForDB.trkangle);
addToDb.WriteEndElement();
addToDb.WriteElementString("Accuracy", gpsDataForDB.accuracy);
addToDb.WriteElementString("FixType", gpsDataForDB.fixtype_f);
addToDb.WriteElementString("FixQuality", gpsDataForDB.fixqual_f);
addToDb.WriteElementString("NumSats", gpsDataForDB.numsats);
addToDb.WriteElementString("ChecksumResult", gpsDataForDB.checksumResultStatusForDisplay);
addToDb.WriteEndElement(); //end Packet
addToDb.Flush();
}
//insert the data into the table
public void populateDbFieldsGPS(GPSPacket gpsDataForDB)
{
try
{
//check where to append from - if table data already exists
sql = "SELECT MAX(packetID) FROM gpsData";
cmd = new MySqlCommand(sql, conn);
result = cmd.ExecuteScalar();
if (result != null)
{
r = Convert.ToInt32(result);
}
else
{
r = 1;
}
//append to the table if already existing
result = null;
//test writing new tables
sql = @"insert into gpsData values("
+ (r + 1) + "," //this is the overall DB ID
+ gpsDataForDB.gpsSessionID + ",'" //note this ID is the packet per session
+ gpsDataForDB.date + "','"
+ gpsDataForDB.time + "','"
+ gpsDataForDB.latitude + "','"
+ gpsDataForDB.longitude + "','"
+ gpsDataForDB.grspd_k + "','"
+ gpsDataForDB.grspd_kph + "','"
+ gpsDataForDB.altitude
+ "');";
cmd = new MySqlCommand(sql, conn);
result = cmd.ExecuteScalar();
}
catch (Exception ex)
{
throw ex;
}
}
public void populateDbFieldsVideo(GPSPacket gpsDataDb, VideoOutputWindow voForDb, string logReason)
{
try
{
//check where to append from - if table data already exists
sql = "SELECT MAX(eventID) FROM videoLog";
cmd = new MySqlCommand(sql, conn);
result = cmd.ExecuteScalar();
if (result != null)
{
r = Convert.ToInt32(result);
}
else
{
r = 2;
}
//append to the table if already existing
result = null;
//test writing new tables
sql = @"insert into videoLog values("
+ (r + 1) + ",'" //this is the overall DB ID
+ gpsDataDb.date + "','"
+ DateTime.Now.ToString("HH:mm:ss") + "','" //use the PC time since if GPS is stuck it'll report the same time!
+ gpsDataDb.latitude + "','"
+ gpsDataDb.longitude + "','"
+ voForDb.currentlyActiveCamera + "','"
+ voForDb.videoLogFilename + "','"
+ logReason + "','" //event descriptions
+ "27760934353" + //sms number
"');";
cmd = new MySqlCommand(sql, conn);
result = cmd.ExecuteScalar();
}
catch (Exception ex)
{
throw ex;
}
}
/*----------------Time and Date Parsing Method
* Input: GPSData object
* Output: Time and date parsed correctly
* Objective: parse time and date from raw numbers and letters to a nice format & to computable values. Assumed time HHMMSS.SSS and date DD/MM/YY
*/
private void timeNiceDisplay(GPSPacket updatedGpsData)
{
string newDateTime; //immutable string so make a new one to copy into
string fixTime; //new temp string for date
string format = "dd/MM/yyyy HH:mm:ss.fff"; //set date time format
System.Globalization.CultureInfo provider = System.Globalization.CultureInfo.InvariantCulture; //provider for display of date and time SA style
newDateTime = updatedGpsData.date.Insert(6, "20"); //assume 2 digit date >2000
//---for UI
updatedGpsData.date = newDateTime;
fixTime = updatedGpsData.time.Insert(2, ":").Insert(5, ":");
updatedGpsData.time = fixTime;
//--end UI formatting
//now format to a DateTime object for later calc
newDateTime += " " + fixTime;
updatedGpsData.dt = DateTime.ParseExact(newDateTime, format, provider); //this will be used for computation
}
private GPSPacket parseGNVTG(string sentenceBuffer, GPSPacket gpsData)
{
int sectionCount = 0;
string subField = "";
foreach (var item in sentenceBuffer)
{
if (item.ToString() != "*") //the asterisk specifies the end of line
{
if (item.ToString() == ",") //increment counter for next segment
{
sectionCount++;
subField = "";
}
switch (sectionCount) //store the fields based on the expected section
{
//GPVTG section 7 is speed in KPH; we need the speed in KPH
case 7:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.grspd_kph = subField; //parse double to a string for display
}
break;
default: break;
}
}
else
{
break;
}
}
//after the asterisk there's a few chars of checksum
//checksum is the first char after the asterisk to the end
checksumGNVTG = sentenceBuffer.Substring(sentenceBuffer.IndexOf('*') + 1);
return(gpsData);
}
private GPSPacket parseGNRMC(string sentenceBuffer, GPSPacket gpsData)
{
int sectionCount = 0; //count for subsections of the GPRMC string
int dateCtr = 0; //for formatting the date nicely
gpsData.date = "";
string subField = "";
foreach (var item in sentenceBuffer)
{
if (item.ToString() != "*") //the asterisk specifies the end of line
{
if (item.ToString() == ",") //increment counter for next segment
{
sectionCount++;
subField = "";
}
switch (sectionCount) //store the fields based on the expected section
{
case 0: break;
//GPRMC section 1 = time in HHMMSS
case 1:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.time = subField;
}
break;
//GPRMC section 2 = fix, A or V
case 2:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.fixtype = subField; //pick the 2nd char ",A" for example
gpsData.friendlyFlagString(gpsData.fixtype, gpsData.fixqual); //get the friendly string for the fix
}
break;
//GPRMC section 3 = Latitude DDMMSS.SSS
case 3:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.latitude = subField; //parse double to a string for display
}
break;
//GPRMC section 4 = Latitude Cardinal Heading
case 4:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.latitude += subField; //add the cardinal heading to the latitude
}
break;
//GPRMC section 5 = Longitude DDMMSS.SSS
case 5:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.longitude = subField; //parse double to a string for display
}
break;
//GPRMC section 6 = Longitude Cardinal Heading
case 6:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.longitude += subField; //add the cardinal heading to the longitude
}
break;
//GPRMC section 7 = Ground speed in Knots
case 7:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.grspd_k = subField;
}
break;
//GPRMC section 8 = Track angle in degrees true
case 8:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.trkangle = subField;
}
break;
//GPRMC section 9 = Date ,DD/MM/YY
case 9:
if (item.ToString() != ",") //make sure the comma isn't included
{
dateCtr++;
if (dateCtr % 2 == 0)
{
subField = item.ToString();
gpsData.date += subField;
gpsData.date += "/"; //format the date nicely
}
else
{
subField = item.ToString();
gpsData.date += subField;
}
}
break;
default:
break;
}
}
else
{
break;
}
}
//after the asterisk there's a few chars of checksum
//checksum is the first char after the asterisk to the end
checksumGNRMC = sentenceBuffer.Substring(sentenceBuffer.IndexOf('*') + 1);
//return completed packet
return(gpsData);
}
private GPSPacket parseGNGGA(string sentenceBuffer, GPSPacket gpsData)
{
int sectionCount = 0;
string subField = "";
foreach (var item in sentenceBuffer)
{
if (item.ToString() != "*") //the asterisk specifies the end of line
{
if (item.ToString() == ",") //increment counter for next segment
{
sectionCount++;
subField = "";
}
switch (sectionCount) //store the fields based on the expected section
{
//GPGGA section 1 = time in HHMMSS
case 1:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.time = subField;
}
break;
//GPGGA section 3 = Latitude DDMMSS.SSS
case 2:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.latitude = subField; //parse double to a string for display
}
break;
//GPGGA section 4 = Latitude Cardinal Heading
case 3:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.latitude += subField; //add the cardinal heading to the latitude
}
break;
//GPGGA section 5 = Longitude DDMMSS.SSS
case 4:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.longitude = subField; //parse double to a string for display
}
break;
//GPGGA section 6 = Longitude Cardinal Heading
case 5:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.longitude += subField; //add the cardinal heading to the longitude
}
break;
//GPGGA section 5 is is the fix quality
case 6:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.fixqual = subField; //add the cardinal heading to the latitude
gpsData.friendlyFlagString(gpsData.fixtype, gpsData.fixqual); //get the friendly name of the fix quality
}
break;
//GGA section 7 is the number of satellites in view
case 7:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.numsats = subField;
}
break;
//section 8 is the accuracy of the GPS fix
case 8:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.accuracy = subField;
}
break;
//section 9 is the altitude ASL
case 9:
if (item.ToString() != ",") //make sure the comma isn't included
{
subField += item;
gpsData.altitude = subField;
}
break;
default: break;
}
}
else
{
break;
}
}
//after the asterisk there's a few chars of checksum
//checksum is the first char after the asterisk to the end
checksumGNGGA = sentenceBuffer.Substring(sentenceBuffer.IndexOf('*') + 1);
return(gpsData);
}
//-------------------------PARSING MEMBER METHODS----------------------------
public GPSPacket parseSelection(string sentenceBuffer, GPSPacket gpsDataForParsing, bool usingWebLogging, int refPackID)
{
GPSPacket updatedGpsData = new GPSPacket(); //sets up a new object which methods return with updated values
if (usingWebLogging == true) //we've got the webserver response OR a failed packet
{
if (!sentenceBuffer.Contains(";"))
{
return(updatedGpsData); //the sentence is invalid
}
else
{
updatedGpsData = newParsingMethod(sentenceBuffer, gpsDataForParsing); //parse the incoming string
if (updatedGpsData.packetID > refPackID || gpsDataForParsing.packetID == 0)
{
updatedGpsData.globalID = updatedGpsData.globalID + 1;
return(updatedGpsData);
}
return(updatedGpsData);
}
}
//-----------------original NMEA parsing-------------------
else //this is a NMEA string and so it starts with a '$"
{
if (!(sentenceBuffer.StartsWith("$"))) //we've got the webserver response OR a failed packet
{
return(updatedGpsData);
}
if (sentenceBuffer.Contains("GNRMC")) //We assume that each "packet" of sentences begins with a GPRMC hence update the packet ID each time a GPRMC is found!
{
packetID++;
updatedGpsData.packetID = packetID;
updatedGpsData = parseGNRMC(sentenceBuffer, gpsDataForParsing);
updatedGpsData = getChecksum(sentenceBuffer, updatedGpsData, 0); //checksum compute with GPRMC
//do some last-minute formatting to the fields based on known issues
updatedGpsData.date = updatedGpsData.date.TrimEnd('/'); //remove trailing "/"
if (updatedGpsData.time.StartsWith("0") || updatedGpsData.longitude.StartsWith("0") || updatedGpsData.latitude.StartsWith("0"))
{
//updatedGpsData.time = updatedGpsData.time.TrimStart('0'); //remove leading zeroes
// updatedGpsData.latitude = updatedGpsData.latitude.TrimStart('0');
// updatedGpsData.longitude = updatedGpsData.longitude.TrimStart('0');
}
//convert the track angle in degrees true to a cardinal heading
trackToCardinal(updatedGpsData);
//convert the time from a horrible string to something nice
timeNiceDisplay(updatedGpsData);
//convert the latitude and longitude from DDMM.MMM(H) to decimal (for Maps and calculations)
///updatedGpsData = latLongConvertToDbl(updatedGpsData);
return(updatedGpsData);
}
else if (sentenceBuffer.Contains("GPGGA"))
{
updatedGpsData = parseGNGGA(sentenceBuffer, gpsDataForParsing);
updatedGpsData = getChecksum(sentenceBuffer, updatedGpsData, 1); //checksum compute with GPGGA
return(updatedGpsData);
}
else if (sentenceBuffer.Contains("GPVTG"))
{
updatedGpsData = parseGNVTG(sentenceBuffer, gpsDataForParsing);
updatedGpsData = getChecksum(sentenceBuffer, updatedGpsData, 2); //checksum compute with GPVTG
//trim off leading zeroes from the speed
if (updatedGpsData.grspd_kph.StartsWith("0"))
{
updatedGpsData.grspd_kph = updatedGpsData.grspd_kph.TrimStart('0');
}
return(updatedGpsData);
}
else
{
return(updatedGpsData); //we don't consider all the other NMEA strings
}
}
}
//-------------------NEW PARSING METHOD------------------------------
public GPSPacket newParsingMethod(string incomingBuffer, GPSPacket gpsData)
{
//incoming format
//PID ; SID ; Date ; Time; Lat; Long Spd; Alt
//7711; 1483; 2016 - 10 - 29; 17:20:21; -29.868922; 30.979895; 0.02; 152.2069
int sectionCount = 0;
string subField = "";
//strip out incoming buffer spaces
incomingBuffer = incomingBuffer.Replace(" ", "");
foreach (var item in incomingBuffer)
{
if (item.ToString() != "*") //the asterisk specifies the end of line
{
if (item.ToString() == ";") //increment counter for next segment
{
sectionCount++;
subField = "";
}
switch (sectionCount) //store the fields based on the expected section
{
//Section 1 is the global packet ID
case 0:
if (item.ToString() != ";") //make sure the comma isn't included
{
subField += item;
gpsData.packetID = Convert.ToInt32(subField); //parse string to a string for display
}
break;
//Section 2 is the GPS session packet ID
case 1:
if (item.ToString() != ";") //make sure the comma isn't included
{
subField += item;
gpsData.gpsSessionID = Convert.ToInt32(subField); //parse string to a string for display
}
break;
//Section 3 is the date
case 2:
if (item.ToString() != ";") //make sure the comma isn't included
{
subField += item;
gpsData.date = subField; //parse string to a string for display
}
break;
//Section 4 is the time
case 3:
if (item.ToString() != ";") //make sure the comma isn't included
{
subField += item;
gpsData.time = subField; //parse string to a string for display
}
break;
//Section 5 is the lat
case 4:
if (item.ToString() != ";") //make sure the comma isn't included
{
subField += item;
gpsData.latitude = subField; //parse string to a string for display
}
break;
//Section 6 is the long
case 5:
if (item.ToString() != ";") //make sure the comma isn't included
{
subField += item;
gpsData.longitude = subField; //parse string to a string for display
}
break;
case 6:
if (item.ToString() != ";") //make sure the comma isn't included
{
subField += item;
gpsData.grspd_kph = subField; //parse string to a string for display
}
break;
case 7:
if (item.ToString() != ";") //make sure the comma isn't included
{
subField += item;
gpsData.altitude = subField; //parse string to a string for display
}
break;
default: break;
}
}
else
{
break;
}
}
return(gpsData);
}
