#!/usr/bin/perl

    # calculates km and miles from a path
    # in a google earth kml file.
    # Idea and formula by Heiko Braak,
    # programming by Jochen Puchalla (c) 2007
    # mail at puchalla dash online dot de
    # License: GPL V2

    # The input record separator is defined by Perl global
    # variable $/.  It can be anything, including multiple
    # characters.  Normally it is "\n", newline.  Here, we
    # say there is no record separator, so the whole file
    # is read as one long record, newlines included.
#    undef $/;

# if (!$ARGS[1])
# {
# 	print STDOUT "usage: kml2length.pl file1.kml [file2.kml ...]\n";
# 	exit(0);
# }

foreach $file (@ARGV)
{
	if (! open(INPUT,"<$file") )
	{
		print STDERR "Can't open input file $file\n";
		next;
	}

	print STDOUT "$file:";

	$filecore=$file;
	$filecore =~ s/.kml$//g;

	if ($file eq $filecore)
	{
		print STDERR "$file is not a kml file\n";
		next;
	}

	$sum=0;
	$n=0;
	$convert="";
	$pi=3.141592;

	while ($line=<INPUT>)
	{
		if ($line =~ /coordinates/)
		{
			$line=<INPUT>;
			$line =~ s/,/\ /g;
			$line =~ s/\ <\/coordinates>\n//g;
			#handle first data line:
			@values = split(/\ /, $line);
			$n=0;
			for ( ; $values[$n+1]!=$values[-2] ; $n=$n+3)
			{
				$sum = $sum + sqrt((($values[$n+4]-$values[$n+1])*$pi*6371/180)*(($values[$n+4]-$values[$n+1])*$pi*6371/180)+(6371*cos($pi/180*$values[$n+4])*$pi*($values[$n+3]-$values[$n])/180)*(6371*cos($pi/180*$values[$n+4])*$pi*($values[$n+3]-$values[$n])/180));
			}
  			print $convert = sprintf "  %5.2f km  %5.2f miles  (%i waypoints)\n" , $sum, $sum*0.62137, $n+2;
		}
	}
	close INPUT;
#	close OUTPUT;
}
exit(0);