use Chart::Gnuplot;
use strict;
use warnings;

sub createDs {
    my ($dsX, $dsY, $name) = @_;
    
    my $dataSet = Chart::Gnuplot::DataSet->new(
        xdata => [@$dsX],
        ydata => [@$dsY],
        title => $name,
        style => "linespoints");
    return $dataSet;
}

sub readDatasets {
    my $filename = shift;
    my $name = "unnamed";
    my @result;
    my (@dataX, @dataY);
    open my $fh, '<', $filename;
    while (my $line = <$fh>) {
        if ($line =~ /^\*\*/) {
            if (@dataX) {
                push @result, createDs(\@dataX, \@dataY, $name);
                @dataX = ();
                @dataY = ();
            }
            next;
        }
        if ($line =~ /^\*/) {
            if ($line =~ /NAME=(.+)/) {
                $name = $1;
            }
            next;
            
        }
        if ($line =~ /(.+), (.+?)$/) {
            push @dataX, $1;
            push @dataY, $2;
        }
    }
    if (@dataX) {
        push @result, createDs(\@dataX, \@dataY, $name);
    }
    return @result;
}

# Create chart object and specify the properties of the chart
my $chart = Chart::Gnuplot->new(
    output => "/tmp/koer.png",
    title  => "Simple testing",
    xlabel => "My x-axis label",
    ylabel => "My y-axis label",
);

my @ds = readDatasets("koer.dat");

# Plot the data set on the chart
$chart->plot2d(@ds);