#!/usr/bin/perl

use LWP::Simple;
use XML::Simple; # I'm just a simple guy.
use Data::Dumper;

# set a path to the gpsbabel program
my $gpsbabel_cmd = 'gpsbabel'; 

# $ARGV could be 'sfo to oak to den' or 'myfile.gpx'
# or myfile1.gpx to sfo to myfile2.gpx to den
my $st = join " ", @ARGV;
my @to_list= split / to /i, $st;

# each location is delimited with the word 'to'
# if a location is a file that exists and ends with gpx
# the file is parsed with gpsbabel and the lat, longs 
# added to our list of locations
my @locations;
# human readable names
my @names;;
foreach my $row (@to_list) {
    $row =~ s/(^\s+)|(\s+$)//g;
    if ($row =~ /gpx$/i) {
        if (! -e $row) {
            warn "Sorry but gpx file $row doesn't exit\n";
            next;
        }
        my @list = `gpsbabel -i gpx -f $row -o csv -F -`;
        foreach my $row (@list) {
            my ($lat, $long, $name) = split (/,/, $row);
            $lat =~ s/\s+//g;
            $long =~ s/\s+//g;
            push @locations, "$lat, $long";;
            push @names, $name;
        }
    } else {
        push @locations, $row;
        push @names, $row;
    }
}

# we have a series of locations that should be google maps parseable
my $route_list = []; # this will be an array of hashrefs of the segments
my $last_location = '';

my $cnt=0;
foreach my $location (@locations) {
    if ($last_location) {
        my $data = get_one_route($last_location, $location);
        my $route =  parse_google_js($$data);
        push @$route_list, $route; 
        print "=" x 65 . "\n";
        print "new route segment $last_location to $location\n";
        print $names[$cnt-1] . ' to ' . $names[$cnt] . "\n";
        output_route($route);
    }
    $last_location = $location;
    $cnt++;
}
exit;

sub get_one_route {
    my ($from, $to) = @_;
    # get the js page
    my $data = get "http://maps.google.com/maps?q=$from+to+$to&output=js";
    return \$data;
}

sub parse_google_js {
    my $st = shift;

    # get rid of everything before the opening <segments> tag
    $st =~ s/^.+\<segments/<segments/s;

    # get rid of everything after the closing </segments>
    $st =~ s/(\<\/segments).+/$1>/s;

    my $xml = XML::Simple->new(
           ForceArray => [ 'segment' ],
           KeyAttr    => [],
           NormaliseSpace => 2
    );
    return $xml-> XMLin($st);
}

sub output_route {
    my $ref = shift;
    foreach my $seg (@{$ref->{segment}}){
        print "-" x 65 . "\n";
        my $cnt=0;
        #print " all of seq is: " . Dumper($seg);
        if (ref($seg->{content})) {
            foreach my $c (@{$seg->{content}}) {
                print " $c\t";
                print $seg->{b}->[$cnt] . "\n";
                $cnt++;
            }
        } else {
                print $seg->{content} . "\t";
                print $seg->{b} . "\n";
        }
        print "$seg->{distance} ($seg->{meters} meters) for $seg->{time}\n";
    }
}