################################################################################
#                                                                              #
# ############################################################################ #
# # Title       : CRC & Number Generating Namer (lol?)                       # #
# # Description : A quick hack for generating a file name with a CRC and     # #
# #               number in it based on some simple input.                   # #
# # Coded by    : Justin "HEYO--!" Lee                                       # #
# # Version     : 1.0                                                        # #
# # Date        : 2008-11-23                                                 # #
# # License     : GNU General Public License v.2                             # #
# #               Copyright (C) 2008  Justin Lee  <kool.name at gmail.com>   # #
# ############################################################################ #
#                                                                              #
# ############################################################################ #
# # This program is free software; you can redistribute it and/or            # #
# # modify it under the terms of the GNU General Public License version 2    # #
# # as published by the Free Software Foundation.                            # #
# #                                                                          # #
# # This program is distributed in the hope that it will be useful,          # #
# # but WITHOUT ANY WARRANTY; without even the implied warranty of           # #
# # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the            # #
# # GNU General Public License for more details.                             # #
# #                                                                          # #
# # You should have received a copy of the GNU General Public License        # #
# # along with this program; if not, write to the Free Software              # #
# # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA            # #
# # 02110-1301, USA.  Or, see: <http://www.gnu.org/licenses/>                # #
# ############################################################################ #
#                                                                              #
################################################################################

use strict;
use String::CRC32;
use Getopt::Std;

my %opt;
getopts('d:s:e:r:E', \%opt) or die "Unable to parse opts: $!\n";
unless (defined $opt{'d'} and defined $opt{'s'} and ($opt{'E'} or defined($opt{'e'}))) {
  print "Usage: @{[ basename($0) ]} -d < /path/to a/directory >" .
        " -s \"Title String\" -e \"ext\"\n" .
        "Use -r < regex > for a custom number finding regex,\n" .
        "default is '[^v](\d+)`.\nUse -E instead of -e \"ext\"" .
        "if you'd like to auto-find extensions.";
  exit 1;
}

my $gex = defined $opt{'r'} ? $opt{'r'} : '[^v](\d+)';

opendir(THERE, $opt{'d'}) or die "Unable to open working directory: $!\n";
my @files = readdir(THERE);
closedir(THERE);

chdir $opt{'d'} or die "Unable to enter working directory: $!\n";
foreach my $file (sort @files) {
  next if -d $file;
  next if $file =~ /^\.\.?$/o;
  my ($num,$ext);
  $file =~ /$gex/oi;
  $num = $1;
  if ($opt{'E'}) {
    $file =~ /(\w+)$/oi;
    $ext = $1;
  }

  open(CRCFILE,$file) or warn("Unable to open file: $!"), next;
  binmode(CRCFILE);
  my $nfile = sprintf(
    "%s - %02d [\U%x\E].%s",
    $opt{'s'},
    $num,
    crc32(*CRCFILE),
    $opt{'E'} ? $ext : $opt{'e'}
  );
  close(CRCFILE);
  rename($file,$nfile) or die "Unable to rename: $!\n";
  print $nfile, "\n";
}