#!/usr/bin/perl

use HTML::LinkExtor;
use Getopt::Std ;
getopts('b:t:');

@ARGV = '-' unless @ARGV;
for my $file (@ARGV) {
  extract($file);
}

sub extract {
  my $file = shift;
  unless (open F, "< $file") {
    warn "Couldn't open file $file: $!; skipping\n";
    return;
  }
  my $p = HTML::LinkExtor->new(undef, $opt_b);
  while (read F, my $buf, 8192) {
    $p->parse($buf);
  }
  for my $ln ($p->links) {
    my @ln = @$ln;
    my $tag = shift @ln;
    next if $opt_t && lc($opt_t) ne lc($tag);
    while (@ln) {
      shift @ln;
      my $url = shift @ln;
      print $url, "\n" unless $seen{$url}++;
    }
  }
}