sub timespan2seconds {
    my $ts = shift;
    my $sc = 0;
    if ($ts =~ m/(?:(\d+)\s+)?(\d+):(\d+)(?::(\d+))?/) {
        $sc += $1 || 0;
        $sc *= 24;
        $sc += $2;
        $sc *= 60;
        $sc += $3;
        $sc *= 60;
        $sc += $4 || 0;
    }
    else {
        my @pt = $ts =~ m/(\d+)([dhms])/g;
        my %sf = (
            'd' => 24 * 60 * 60,
            'h' => 60 * 60,
            'm' => 60,
            's' => 1
            );
        $sc += shift(@pt) * $sf{shift(@pt)} while (@pt);
    }
    return $sc;
}