use 5.010;
use strict;
use warnings;

use Mojo::UserAgent;
use Mojo::IOLoop;
use Mojo::URL;

# FIFO queue
my @names = qw(zezima fred bill john jack);

# User agent following up to 5 redirects
my $ua = Mojo::UserAgent->new( inactivity_timeout => 1 );

sub url_for_name {
    my $name = shift;
    return "http://rscript.org/lookup.php?type=track&time=62899200&user=$name&skill=all";
}

# Crawler
my $crawl;
$crawl = sub {
    my $id = shift;

    return unless my $name = shift @names;
    say "Looking for $name";

    # Fetch non-blocking just by adding a callback
    $ua->get(
        url_for_name($name) => sub {
            my ( $ua, $tx ) = @_;

            my $body = $tx->res->body;
            if ( $body =~ m/gain:Overall:\d+:(\d+)/i ) {
                say "$name $1";
            }
            elsif ( $body =~ m/(ERROR)/i ) {
                say "$name doesn't exist";
            }
            else {
                say "$name 0";
            }

            # Next
            $crawl->($id);
        }
    );
};

# Start a bunch of parallel crawlers sharing the same user agent
$crawl->($_) for 1 .. 4;

# Start reactor
Mojo::IOLoop->start;