#!/usr/bin/perl

# batch processor for removing track numbers from filenames of mp3s and making
# m3u files out of them

#$Id: denumerate 143 2005-09-12 16:08:08Z steve $
#$Log$
#Revision 1.4  2005/09/12 16:08:08  steve
#slightly better regex
#
#Revision 1.3  2003/03/05 07:27:03  steve
#deals with a . after the number
#
#Revision 1.2  2003/01/25 23:11:41  steve
#adds comments where missing files should be
#
#Revision 1.1  2002/12/13 21:07:21  steve
#Initial revision
#
###############################

use strict; #cracks the whip
use Getopt::Std;

getopts("hm:");
our( $opt_h, $opt_m );

my @files = @ARGV;

usage() if ($opt_h || !@files);

# the default m3u filename is the current directory's name with .m3u added
my ($def_m3u) = $ENV{'PWD'} =~ /.+\/(.+?)$/;
$def_m3u     .= ".m3u";

my $m3u_file = $def_m3u;
$m3u_file = $opt_m if defined $opt_m;

my @playlist = ();
foreach my $file (sort @files){
  # try to pull out the track number if it's there
  if(my ( $tracknum, $filename ) = $file =~ /^\s*(\d{1,2})\.?\s*(?:\-{1,8}\s*)?(.+)$/){

    my $new_filename = $file;

    if( rename $file, $filename ){
	print "renamed \"$file\" to \"$filename\"\n";
	$new_filename = $filename;
    }else{
	warn "could not rename \"$file\" to \"$filename\": $!\n";
    }

    $playlist[$tracknum] = $new_filename;

  }else{
    warn "cannot extract a track number from $file\n";
  }

}

if( @playlist ){
    
    print "Writing track list to $m3u_file\n";
    open M3U,  ">$m3u_file" or die "cannot open m3u file (\"$m3u_file\") ".
	"for writing: $!\n"; 

    for(my $i = 1; $i < @playlist; $i++){

	if( $playlist[$i] ){
	    print M3U $playlist[$i], "\n";
	}else{
	    print M3U "# track $i goes here\n";
	}
    }
    close M3U;
}


sub usage{
  die<<USAGE;
usage: $0 [-m m3u file] files

takes a bunch of mp3 or whatever files that start with numbers and some 
delimeters, renames them without the track numbers and puts them in order
in an m3u file. (defaults to current_directory's_name.m3u)

Copyright(C) 2002 Steve Pomeroy <steve\@staticfree.info>

USAGE
}