My first thought was Text::CSV as well, but I'm not sure it'll help you here. You don't have true 'comma separated values' format. CSV does not use parens to group items - it uses a single character. Parens work in pairs.

If you have any control over the format, you might consider changing it to match the CSV spec - something standard. Then Text::CSV will help you. The example below is only slightly modified from the examples in the POD

#!/usr/bin/perl -w
use strict;
use Text::CSV_XS;

while( <DATA> ){
  my $line = $_;
  my @input;
  my $csv = Text::CSV_XS->new({  # defaults are: ["]["][,][0]
      quote_char  => '"',
      escape_char => '"',
      sep_char    => ',',
      binary      => 0
  });
  if( $csv->parse( $line ) ){
    @input = $csv->fields;
  } else {
    my $err = $csv->error_input;
    warn "Text::CSV_XS->parse() failed in line $. on argument '"
      , $err, "'\n";
  }
  foreach my $item (@input){
    print "$item\n";
  }
  print "\n";
}

# first line parses 'correctly' - second does not.
__DATA__
this,that,those,"these (not enough, nope, never)",there
this, that, those, these (not enough, nope, never), there
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