#!/usr/bin/perl -w

# tolower converts a list of given filenames to lowercase.  Optionally
# converts spaces and "%20" to underscores and removes punctuation
# characters such as periods, commas, and question marks.
#
# Copyright (C) 2005-2006 Jason Blevins <jrblevin@sdf.lonestar.org>
#
# Created: Durham, August 2, 2005
# Last Modified: March 13, 2008 16:09 EDT
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or (at
# your option) any later version.
#
# 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.

use strict;
use Getopt::Std;

our($opt_h, $opt_v, $opt_s, $opt_p, $opt_e);

getopts('esphv');

if ($opt_h) {
    print_usage();
    exit();
}

if (defined $opt_p & defined $opt_e) {
    print "Warning: Both -p and -e were given, assuming -p.\n"
}

foreach (@ARGV) {
    my($extension, $original_filename, $new_filename);

    $original_filename = $_;

    # Print filename if verbosity requested
    if ($opt_v) { print "$_ -> " };

    # Convert to lower case
    s/(\w)/\L$1/g;

    if ($opt_s) {
        s/ /_/g;
        s/%20/_/g;
    }
    # Store the extension if -p is given
    if ($opt_p) {
        s#^(.*)\.(\w+)$#$1#;
        $extension = $2;
    }
    if (defined $opt_p | defined $opt_e) {
        s#[^\w -]+##g;
    }

    $new_filename = $_;
    if (defined $opt_p & defined $extension) { $new_filename .= ".$extension"; }
    if ($opt_v) { print "$new_filename\n"; }

    # Rename the file
    rename $original_filename, $new_filename;
}


sub print_usage {
    my $usage = "usage: tolower [options] file_1 [file_2 ...]\n\n" .
      "options:\n\t-h\tdisplay help\n\t-v\tbe verbose\n" .
      "\t-s\tconvert space and \"%20\" to underscore\n" .
      "\t-p\tremove punctuation (preserves extensions)\n" .
      "\t-e\tremove punction (no extensions)\n\n" .
      "note: -p and -e remove all characters except letters, numbers, \"-\", and \"_\".\n";
    print $usage;
}