$input = q|http://abc.org,http://de,f.org,https://ghi.org|;

##</code><code>##

    @captures = (
        'http://abc.org',
        'http://de,f.org',
        'https://ghi.org',
    );

##</code><code>##

    @captures = (
        'http://abc.org',
        'http://de,f.org',
    );

##</code><code>##

use strict;
use warnings;
use 5.010_001;
use Test::More;

my @raw_inputs = (
    'http://abc.org',
    'http://de,f.org',
    'https://ghi.org',
    'http://jkl.org',
);
my @inputs = ( $raw_inputs[0] );
for my $q (1..3) {
    push @inputs, join(',' => @raw_inputs[0..$q]);
}

is_deeply(
    _recognize_limited_urls($inputs[0], 3),
    [ $raw_inputs[0] ],
    "1 URL",
);

is_deeply(
    _recognize_limited_urls($inputs[1], 3),
    [ @raw_inputs[0..1] ],
    "2 URLs (one containing a comma)",
);

is_deeply(
    _recognize_limited_urls($inputs[2], 3),
    [ @raw_inputs[0..2] ],
    "3 URLs (one containing a comma)",
);

is_deeply(
    _recognize_limited_urls($inputs[3], 3),
    [ @raw_inputs[0..2] ],
    "Still only 3 URLs (one containing a comma); reject those over max",
);

done_testing();

sub _recognize_limited_urls {
  my ($input, $max) = @_;
  my $str = $input;
  my $pattern = qr/^(http.*?)(?:,(http.*?))?$/;
  my $count = 0;
  my @captures = ();
  LOOP: while ($count < $max) {
    my ($capture, $balance);
    if ($str and $str =~ m/$pattern/) {
      ($capture, $balance) = ($1, $2);
      push @captures, $capture;
      $str = $balance;
      $count++;
    }
    else {
      last LOOP;
    }
  }
  return \@captures;
}