flac2mp3

use strict;
use warnings;
use File::Find::Rule;

my %id_names = (
  artist      => 'ta',
  year        => 'ty',
  date        => 'ty', # alias
  comment     => 'tc',
  album       => 'tl',
  title       => 'tt',
  tracknumber => 'tn',
  genre       => 'tg',
);

my $target_dir = 'mp3';

my @files = File::Find::Rule
    ->name('*.flac')
    ->file()
    ->in('.');

exit 0 unless @files;

mkdir $target_dir unless -d $target_dir;

for my $file (@files) {
  my $q_file = quotemeta($file);
  (my $mp3_file = $q_file) =~ s/flac/mp3/;
  my @data = qx(metaflac --export-tags-to=- $q_file);

  my %id;
  foreach (@data) {
    chomp;

    my ($key, $value) = split('=', $_, 2);
    $id{$key} = $value;
  }
  $id{tracknumber} .= '/' . scalar(@files) if (exists $id{tracknumber});

  my $ids = '';

  foreach(keys %id) {
    $ids .= ' --' . $id_names{$_} . qq! "$id{$_}"!;
  }

  my $cmd = "flac -c -d $q_file | lame -V 0 $ids - $target_dir/$mp3_file";

  qx($cmd);
}