#!/usr/bin/perl
use strict;
use warnings;

use LWP::RobotUA;
use HTML::LinkExtor;
use HTML::TokeParser;
use URI::URL;

use Data::Dumper; # for show and troubleshooting

my $ua = LWP::RobotUA->new();

foreach my $forum_id (17, 3) {
	my $url = "http://www.nukeforums.com/forums/viewforum.php?f=$forum_id";
	my $links = get_threads($url);
	foreach my $page (@$links) {
		...
	}
}

sub get_thread {
	...
}

sub get_threads {
	my $page = shift;

	my @links;
	my $lp = HTML::LinkExtor->new(sub {
		my($tag, %attr) = @_;
		return unless exists $attr{'href'};
		return if $attr{'href'} !~ /^viewtopic\.php\?t=/;
		push @links, values %attr;
	});

	my $request = HTTP::Request->new(GET => $url);
	my $response = $ua->request($request, sub {$lp->parse($_[0])});

	# Expand URLs to absolute ones
	my $base = $response->base;
	return [ map { url($_, $base)->abs } @links ];
}