#!/usr/bin/perl
use strict;
###############################################3
#
#  THIS SCRIPT MAY REMOVE FILES FROM YOUR SYSTEM, MAKE A BACKUP FIRST.  USE AT YOUR OWN RISK
#
#  Simple digital music m3u-producing perl/shell script
#
#  REQUIRES: Perl, GNU find, GNU xargs  (most Linux systems have these by default)
#
#  I use this to help organize my flac collection and make m3u files.  
#  (Free lossless audio codec:  http://flac.sf.net/)
#  It should work for ogg, mp3 or any other files you can wrangle into a m3u
#
#  You may feel free to use it for personal use only under the terms of the GNU GPL 
#  a copy of which can be found at http://gnu.org/copyleft/gpl.html
#
#  SUGGESTED USAGE: -------------------------------------------------------------------------------
#
#  Place this script in the directory below your music files.  Here's how I lay mine out:
# 
#  All
#  Blues
#  Classical
#  Compilations
#  Guitar
#  Jazz
#  Rock
#
#  Example path:  tunes/All/Zappa, Frank/Weasels Ripped My Flesh/the_mothers_of_invention-09_oh_no.flac
#
#  Only "All" has the actual files under it, and the others contain relative links to the
#  other files under All based on the genre of the group.  I find this to alllow the most
#  flexibility in making playlists.  You should do the same if you want to use this script
#  in unmodified form.
#
#  Set the parameters below and run 'perl mkm3us.pl' in the directory just below your 'All' 
#  folder to set up all your m3u files automatically.
#
#  Any deviations from this setup will require modifications, but hopefully it's not too 
#  hard to understand.
#
#  Copyright 2005 Matthew Steven http://www.matts.org/
#
###############################################3
# Config.  0 means no and 1 means yes

# Tell us everything you can about what you are doing, script
my $verbose=1;

# Remove all existing m3u's before starting
my $cleanrun=1;

# Make all m3us from the files in the directories below
my $makeall=1;

# List of folders containing your music and links to your music folders.  Do not include folder 'All' here.
my @genres=('Blues','Classical','Compilations','Guitar','Jazz','Rock');

# The name of the folder containing actual music files.
my $allfolder='All';

# The extention your files all have.  They need to be the same, or you need to get hacking
my $ext = 'flac';

# The rest you can change only if you really know what you're doing...  
################################################3

my $startdir=`pwd`;
chomp $startdir;

chdir "$startdir/$allfolder";
print "Getting started in ".`pwd`;


if($cleanrun){
	print "Flushing any existing m3u's under $startdir in 10 seconds.... \nCTRL-C to interrupt if you're not sure...";
	`sleep 10s`;
	`find $startdir -name '*.m3u' -print0|xargs -0 rm -f `;
}
if(! -f "$startdir/$allfolder/All-All.m3u"){
	print "No all-music file found, building it...\n";
	`find . -name "*.$ext" | perl -pe "s:^\.\/::g" > $startdir/$allfolder/All-All.m3u`;
}


if($makeall){

	print "Making m3u files based on the contents of $startdir/$allfolder/All-All.m3u\n";

	open(F,"<$startdir/$allfolder/All-All.m3u") or die $!;
	while(<F>){
		chomp;
		/^(.*)\/([^\/]+$ext)$/;
		my $albumname = $1;
		my $song = $2;
		my $on=$albumname;
		$albumname =~ s/[^\-_0-9a-zA-Z]/_/g;
		`echo "$on/$song" >> "$startdir/$allfolder/$albumname.m3u"`;
		print "$song added to $albumname\n" if $verbose;
		foreach my $g (@genres){
			if(-e "../$g/$on" && ! -f "../$g/$albumname.m3u"){
				`cd ../$g && ln -s ../$allfolder/$albumname.m3u && cd ../$allfolder`;
				print "Linked $albumname to $g\n" if $verbose;
			}
		}
	}
	close(F);
}

print "Making overall m3u files for each subfolder...\n";

push @genres, $allfolder;
foreach my $g (@genres){
	`rm -f $startdir/$g/All-$g.m3u $startdir/All-$g.m3u`;
	`cd $startdir/$g && cat *.m3u > All-$g.m3u`;
	open(F,"<$startdir/$g/All-$g.m3u") or die $!;
	while(<F>){
		chomp;
		`echo "$g/$_" >> $startdir/All-$g.m3u`;
	}
	close(F);
}

print "All done.";
exit;