sprintf(slat, "%f", Lat);
sprintf(slon, "%f", Lon);

#pragma config(Sensor, S1,     DGPS,                sensorI2CCustom)
#include "drivers/dexterind-gps.h"

// This program is based off of work done by Xander.  Visit his website at http://mightor.wordpress.com/
// Read the Dexter Industries GPS sensor for positional data.  For more on the Dexter Industries GPS Sensor
// vist http://www.dexterindustries.com
// This code is an example of reading the GPS sensor for positional data.
//
// This program datalogs a journey, and saves the coordinates in KML style format for display on google earth.
// It first generates a header.
// Then it adds lat/long data into the file.
// When the program is stopped with the red button, the footer is inserted.
// The file can be saved to the computer.  Use notepad (or equivalent) to "Save As" *.kml
// You should be able to pull the file up and see on Google Earth.

// Note that the default filename in this program is "Path.txt".  You can
// rename it anything you like, as long as it's *.txt.

// Give a file name.
// Will have to rename this as a .kml file after downloading to desktop.


//*****************************************************************************************************************

string slat = "";
string slon = "";
int mode_continous=0;
int mode_datapoint=0;
int mode_exit=0;
int interval=10; //continous mode writes data every 10 seconds
int maxtime;
int recordtime;
long valTime10;
const string sFileName = "Path.txt";  // Our destination KML File
[color=#4000FF][/color]
TFileIOResult nIoResult;
TFileHandle hFileHandle;
// NOTE ON FILESIZE:  Note that the header that's inserted by default is about 800 bytes.
// NOTE ON FILESIZE:  Every data point added is about 30 bytes in size.
int nFileSize = 30000; //about 162 min datalogging with an interval of 10s

void write_header()
{

   WriteString(hFileHandle, nIoResult, "<?xml version=\'1.0\'");
   WriteString(hFileHandle, nIoResult, " encoding= \'UTF-8\'");
   WriteString(hFileHandle, nIoResult, "?>");
   WriteText(hFileHandle, nIoResult, "\r\n");

   WriteString(hFileHandle, nIoResult, "<kml xmlns=");
   WriteText(hFileHandle, nIoResult, "\'http://www.opengis");
   WriteText(hFileHandle, nIoResult, ".net/kml/2.2\'");
   WriteText(hFileHandle, nIoResult, ">");
   WriteText(hFileHandle, nIoResult, "\r\n");
   WriteText(hFileHandle, nIoResult, "  <Document>\r\n");
   WriteText(hFileHandle, nIoResult, "    ");
   WriteText(hFileHandle, nIoResult, "<name>Paths</name>");
   WriteText(hFileHandle, nIoResult, "\r\n");

   WriteText(hFileHandle, nIoResult, "    <description>");
   WriteText(hFileHandle, nIoResult, "</description>\r\n");
   WriteText(hFileHandle, nIoResult, "    <Style id=\'yel");
   WriteText(hFileHandle, nIoResult, "lowLineGreenPoly\'>");
   WriteText(hFileHandle, nIoResult, "\r\n");

   WriteText(hFileHandle, nIoResult, "      <LineStyle>");
   WriteText(hFileHandle, nIoResult, "\r\n");
   WriteText(hFileHandle, nIoResult, "        <color>7f0");
   WriteText(hFileHandle, nIoResult, "0ffff</color>");
   WriteText(hFileHandle, nIoResult, "\r\n");

   WriteText(hFileHandle, nIoResult, "        <width>4</");
   WriteText(hFileHandle, nIoResult, "width>\r\n");
   WriteText(hFileHandle, nIoResult, "      </LineStyle>");
   WriteText(hFileHandle, nIoResult, "\r\n");

   WriteText(hFileHandle, nIoResult, "      <PolyStyle>");
   WriteText(hFileHandle, nIoResult, "\r\n");
   WriteText(hFileHandle, nIoResult, "        <color>7f0");
   WriteText(hFileHandle, nIoResult, "0ff00</color>");
   WriteText(hFileHandle, nIoResult, "\r\n");

   WriteText(hFileHandle, nIoResult, "      </PolyStyle>");
   WriteText(hFileHandle, nIoResult, "\r\n");
   WriteText(hFileHandle, nIoResult, "    </Style>");
   WriteText(hFileHandle, nIoResult, "\r\n");

   WriteText(hFileHandle, nIoResult, "    <Placemark>");
   WriteText(hFileHandle, nIoResult, "\r\n");
   WriteText(hFileHandle, nIoResult, "      <name>Absol");
   WriteText(hFileHandle, nIoResult, "ute Extruded</name>");
   WriteText(hFileHandle, nIoResult, "\r\n");
   WriteText(hFileHandle, nIoResult, "      <description>");
   WriteText(hFileHandle, nIoResult, "</description>\r\n");
   WriteText(hFileHandle, nIoResult, "      <styleUrl>#");
   WriteText(hFileHandle, nIoResult, "yellowLineGreenPoly");
   WriteText(hFileHandle, nIoResult, "</styleUrl>\r\n");
   WriteText(hFileHandle, nIoResult, "      <LineString>");
   WriteText(hFileHandle, nIoResult, "\r\n");
   WriteText(hFileHandle, nIoResult, "        <extrude>");
   WriteText(hFileHandle, nIoResult, "10</extrude>\r\n");
   WriteText(hFileHandle, nIoResult, "        <tessellate");
   WriteText(hFileHandle, nIoResult, ">10</tessellate>\r\n");
   WriteText(hFileHandle, nIoResult, "        <altit");
   WriteText(hFileHandle, nIoResult, "udeMode>clampToG");
   WriteText(hFileHandle, nIoResult, "round");
   WriteText(hFileHandle, nIoResult, "</altitudeMode>\r\n");
   WriteText(hFileHandle, nIoResult, "        ");
   WriteText(hFileHandle, nIoResult, "<coordinates> ");
   //Phew!
}

void write_footer()
{

   WriteText(hFileHandle, nIoResult, "\r\n");
   WriteText(hFileHandle, nIoResult, "\r\n");
   WriteText(hFileHandle, nIoResult, "        ");
   WriteText(hFileHandle, nIoResult, "</coordinates>");
   WriteText(hFileHandle, nIoResult, "\r\n");
   WriteText(hFileHandle, nIoResult, "      </LineString>");
   WriteText(hFileHandle, nIoResult, "\r\n");
   WriteText(hFileHandle, nIoResult, "    </Placemark>");
   WriteText(hFileHandle, nIoResult, "\r\n");
   WriteText(hFileHandle, nIoResult, "  </Document>");
   WriteText(hFileHandle, nIoResult, "\r\n");
   WriteText(hFileHandle, nIoResult, "</kml>");
   WriteText(hFileHandle, nIoResult, "\r\n");
}

void write_GPS_coords()
{
   // Function reads coordinates from GPS, converts to decimal degrees.
   // Writes coordinates to file.

   float Lat = (float)DGPSreadLatitude(S1)/1000000;     // Lat will be in decimal degrees
   float Lon = (float)DGPSreadLongitude(S1)/1000000;    // Lon will be in decimal degrees

   nxtDisplayStringAt(0, 20, "Lat:");
   nxtDisplayStringAt(0, 10, "Lon:");

   nxtDisplayStringAt(30, 20, "%3.6f", Lat);
   nxtDisplayStringAt(30, 10, "%3.6f", Lon);

   StringFormat(slat, "%3.6f", Lat);
   StringFormat(slon, "%3.6f", Lon);

   WriteText(hFileHandle, nIoResult, "\r\n");
   WriteText(hFileHandle, nIoResult, "   ");
   WriteText(hFileHandle, nIoResult, slon);
   WriteText(hFileHandle, nIoResult, ",");
   WriteText(hFileHandle, nIoResult, slat);
   WriteText(hFileHandle, nIoResult, ",");
   WriteText(hFileHandle, nIoResult, "0");

}

void startscreen()
{
   nxtDisplayStringAt(0, 60, "GPS Datalogger");
   nxtDisplayStringAt(0, 50, "Waiting!");
   nxtDisplayStringAt(0, 40, "Left: single point");
   nxtDisplayStringAt(0, 30, "Right: continuous");
   nxtDisplayStringAt(0, 20, "Center: stop");
}

task checkbutton()
{
   while (true)
   {
      wait1Msec(800);// make sure, that button is pressed for 800 ms, because to avoid unintentionally pressing
      switch(nNxtButtonPressed)
      {
      case 1:
         mode_continous=1;
         ClearTimer(T1);
         recordtime=recordtime*60;
         break;

      case 2:
         mode_datapoint=1;
         break;

      case 3:
         mode_exit=1;
      }
      if (mode_continous==1 && mode_datapoint==1) //pause of continous mode
      {
         eraseDisplay();
         startscreen();
         mode_continous=0;
         mode_datapoint=0;
      }
      if (mode_exit==1)
      {
         //end of datalogging
         wait1Msec(500);
         write_footer();
         Close(hFileHandle, nIoResult);
         StopAllTasks();
      }
   }
}


task main()
{
   hFileHandle = 0;
   Delete(sFileName, nIoResult);
   OpenWrite(hFileHandle, nIoResult, sFileName, nFileSize);
   write_header(); //  Writes the header of the kml file.

   eraseDisplay();
   nxtDisplayTextLine(0,"Eingabe des Daten");
   nxtDisplayTextLine(1,"intervalls[s]");

   while (nNxtButtonPressed!=3)
   {
      if (nNxtButtonPressed==1)
      interval++;
      wait1Msec(150);
      if (nNxtButtonPressed==2)
      interval--;
      wait1Msec(150);
      maxtime=(long)(nFileSize-800)*interval/(60*30);//in minutes
      nxtDisplayTextLine(3,"Intervall[s]:%d",interval);
      nxtDisplayTextLine(5,"max.Zeit[min]:%d",maxtime );
   }
   eraseDisplay();
   StartTask(checkbutton);

   while (mode_exit !=1)
   {
      if(mode_datapoint==1)
      {
         nxtDisplayStringAt(0, 60, "GPS Datalogger");
         nxtDisplayStringAt(0, 30, "Writing Point");
         write_GPS_coords();
         wait1Msec(1000);
         eraseDisplay();
         mode_datapoint=0;
      }
      if (mode_continous==1)
      {
         eraseDisplay();
         valTime10 = time10[T1];
         recordtime=(recordtime+valTime10/100)/60;
         nxtDisplayStringAt(0, 60,"Recordtime: %d",recordtime);
         nxtDisplayStringAt(0, 50,"Max.time: %d",maxtime);
         write_GPS_coords();
         wait10Msec(interval*100);//write data according interval!

         if (recordtime==maxtime-1)
         {
            wait1Msec(500);
            write_footer();
            Close(hFileHandle, nIoResult);
            StopAllTasks();
            mode_exit=1;//when reaching the max. recordtime, exit with closing file
            eraseDisplay();
         }

      }

      startscreen();
   }


}

//modified by Sigtrygg, April 2013