#!/usr/bin/perl

use Data::Dumper;

use Getopt::Std;

my %opts;

getopts('hf:a:o:', \%opts);

$inBiking = 0;
$inLap = 0;
$inTrack = 0;
$inTrackpoint = 0;

sub usage() {
    printf "Usage\n";
    printf "\t-f hst file: historic file from Garmin Training Center\n";
    printf "\t-h         : this help\n";
    printf "\t-a +lat    : latitude offset\n";
    printf "\t-o +lon    : longitude offset\n";
}

if (!defined $opts{f}) {
    usage();
    exit;
}

if (defined $opts{h}) {
    usage();
    exit;
}

$lat_offset = 0.0;
$lon_offset = 0.0;

if (defined $opts{o}) {
    $lon_offset = $opts{o};
}

if (defined $opts{a}) {
    $lat_offset = $opts{a};
}

# how many points in the path
$points = 0;
$outFileName = "";

open INFILE, $opts{f};

while (<INFILE>) {
    chomp();

    if ($inBiking) {
	if ($inLap) {
	    if (/<\/Lap>/) {
		$inLap = 0;
		$lapName = "unknown";

		print(FD "</coordinates>\n</LineString>\n</Placemark>\n</Document>\n</kml>\n");
		close FD;

		if ($points == 0) {
		    unlink $outFileName or die "rm";
		}
		next;
	    }

	    if ($inTrack) {
		if ($inTrackpoint) {
		    if (/<\/Trackpoint>/) {
			$inTrackpoint = 0;
			if ($lat > 0.0
			    && $lon > 0.0) {
			    printf(FD "%f,%f,%f\n", 
				   $lon + $lon_offset,
				   $lat + $lat_offset,
				   $alt);
			    $points++;
			}
			next;
		    }

		    if (/<LatitudeDegrees>(.*)<\/LatitudeDegrees>/) {
			$lat = $1;
			next;
		    }

		    if (/<LongitudeDegrees>(.*)<\/LongitudeDegrees>/) {
			$lon = $1;
			next;
		    }

		    if (/<AltitudeMeters>(.*)<\/AltitudeMeters>/) {
			$alt = $1;
			next;
		    }
		} else {
		    if (/<\/Track/) {
			$inTrack = 0;
			next;
		    }

		    if (/<Trackpoint>/) {
			$inTrackpoint = 1;
			$lat = 0;
			$lon = 0;
			$alt = 0;
			next;
		    }
		}
	    } else {
		if (/<Track/) {
		    $inTrack = 1;
		    next;
		}
	    }
	} else {
	    if (/<Lap StartTime="(.*)"/) {
		$inLap = 1;
		$lapName = $1;

		$lapName =~ s/:/-/g;
		printf("lap = %s\n", $lapName);

		$outFileName = "export-KML-$lapName.kml";
		open FD, "> $outFileName" or die "create $outFileName";
		$points = 0;

		print FD <<EOF;
<?xml version="1.0" encoding="UTF-8"?>
<kml xmlns="http://earth.google.com/kml/2.1">
  <Document>
    <name>Paths exported from Garmin 305</name>
    <description>from Garmin hst file</description>
    <Style id="yellowLineGreenPoly">
      <LineStyle>
        <color>7f00ffff</color>
        <width>4</width>
      </LineStyle>
      <PolyStyle>
        <color>7f00ff00</color>
      </PolyStyle>
    </Style>

    <Placemark>
EOF
;

		printf FD "<name>%s</name>\n", $lapName;
		if ($lat_offset != 0.0 ||
		    $lon_offset != 0.0) {
		    printf FD "<description>Offset lat=%f, lon=%f</description>", $lat_offset, $lon_offset;
	    }

		print FD <<EOF;
      <styleUrl>#yellowLineGreenPoly</styleUrl>
      <LineString>
        <extrude>1</extrude>
        <tessellate>1</tessellate>
        <altitudeMode>clampToGround</altitudeMode>
        <coordinates>
EOF
;

		next;
	    }
	}
    } else {
	if (/<Biking Name=/) {
	    $inBiking = 1;
	}
    }
}

close INFILE;