#!/usr/bin/perl
#
# $Id: mp3shell,v 0.24 2000/02/21 20:20:41 toffi Exp $
#
#
# mp3shell	Shell like interface for managing and playing mp3s
#
# Author:	Christoph Hellwig <schch@pe.tu-clausthal.de>
#
#
# $Log: mp3shell,v $
# Revision 0.24  2000/02/21 20:20:41  toffi
#  - fixed small bug in ' Playing MPEG stream' line
#
# Revision 0.23  2000/02/20 20:10:06  toffi
#  - fixed rcfile parsing
#
# Revision 0.22  2000/02/20 19:37:31  toffi
#  - added clear command
#  - wrote manpage
#  - added Makefile and README
#
# Revision 0.21  2000/02/20 16:58:51  toffi
#  - readded support for skipping one song
#  - added sighandlers
#
# Revision 0.2  2000/02/20 16:16:16  toffi
# - added support for rcfile
# - implemented statusbar
#
# Revision 0.13  2000/02/14 21:24:20  toffi
# - even more bugfixes
#
# Revision 0.12  2000/02/14 17:29:25  toffi
#  - some misc bugfixes
#  - added some new useless features :)
#
# Revision 0.11  2000/02/13 14:07:53  toffi
#  - first simple patch
#

use DB_File;
use Fcntl;
use Getopt::Std;
use Term::ReadKey;
use Term::ReadLine;
require "find.pl";

getopts('c:');

# config

$VERSION = "v0.12";
$ext = $$;
$fifo = "/tmp/fifo.$ext";
$maxlen = 30;
$prompt = "mp3 shell> ";
$mpg123opts = "";

$cf_file = "$ENV{'HOME'}/.mp3shellrc";
$ba_file = "$ENV{'HOME'}/.mp3shell.by_artist";
$bn_file = "$ENV{'HOME'}/.mp3shell.by_name";

#$SIG{__DIE__} = $SIG{INT} = \&quit;
#if ( -f $cf_file ) {
#	open (CFG, "<$cf_file");
#	while(<CFG>) { 
#		eval $_;
#	}
#	close CFG;
#}

$term = new Term::ReadLine 'Perl mp3 shell';
$OUT = $term->OUT || STDOUT;

#if($opt_c) {
#	unlink $ba_file;
#	unlink $bn_file;
#}

$DB_BTREE->{'flags'} = R_DUP;

$ba_h = tie %playlist_ba, "DB_File", $ba_file, O_RDWR|O_CREAT, 0640, $DB_BTREE;
$bn_h = tie %playlist_bn, "DB_File", $bn_file, O_RDWR|O_CREAT, 0640, $DB_BTREE;

if($opt_c) {
	print $OUT "Recreating mp3 database using $opt_c as base directory\n"
	&find($opt_c);
}

if (system "mkfifo $fifo || mknod -p $fifo") {
	die "mk{nod,fifo} $fifo failed";
}

sub wanted {
	s/^(.*)\.mp3$/\1/ or return;
	
	open (MP3, "<$name");
	seek MP3, -128, 2;
	read MP3, $tag, 3;

	if($tag eq "TAG") {
		my ($title, $artist);
		read MP3, $title, 30;
		$title =~ s/\s*$//;
		$playlist_bn{$title} = $name;

		read MP3, $artist, 30;
		$artist =~ s/\s*$//;
		$playlist_ba{$artist} = $name;
	} elsif(/(.+?)\s-\s(.*)/) {
		$playlist_ba{$1} = $name;
		$playlist_bn{$2} = $name;
	} else {
		$playlist_ba{'Unknown'} = $name;
		$playlist_bn{$_} = $name;
	}
	
	close (MP3);
}

sub help {
	print $OUT "mp3 engine $VERSION\n\n";
	print $OUT "The following commands are aviable:\n";
	print $OUT "\n\tlist /expr/\n";
	print $OUT "\t\tlist all mp3 files matching expr\n";
	print $OUT "\n\tplay /expr/\n";
	print $OUT "\t\tplay all mp3 files matching expr\n";
	print $OUT "\n\tquit\n";
	print $OUT "\t\tquit mp3 engine\n";
	print $OUT "\n\thelp\n";
	print $OUT "\t\tgive this help screen\n";
}

sub id3 {
	my ($file, $what) = @_;
	my ($tag, %id3);
	
	open (MP3, "<$file");
	
	seek MP3, -128, 2;
	read MP3, $tag, 3;
	
	if($tag eq "TAG") {
		read MP3, $id3{'title'}, 30;
		read MP3, $id3{'artist'}, 30;
		read MP3, $id3{'album'}, 30;
		read MP3, $id3{'year'}, 4;
		read MP3, $id3{'comment'}, 30;
	} else {
		$id3{'title'} = $what." (???)";
	}
	
	close (MP3);
	return %id3;
}

sub step {
	my ($what, $exec) = @_;
	my ($i, $k, $v, $s);

	$what =~ s/^\/([^\/]+)\/$/\1/;

	$s = $bn_h->seq ($k, $v, R_FIRST);

	until ($s) {
		&$exec("Title", $k ,$v, ++$i) if ($k =~ /$what/i);
		$s = $bn_h->seq ($k, $v, R_NEXT);
	}

	$s = $ba_h->seq ($k, $v, R_FIRST);

	until ($s) {
		&$exec("Artist", $k ,$v, ++$i) if ($k =~ /$what/i);
		$s = $ba_h->seq ($k, $v, R_NEXT);
	}
}

$list = sub {
	my ($string, $what, $where, $count) = @_;

	print $OUT "\t\t$string: $what\n";
	print $OUT "\t\tFile: $where\n\n";
};

$play = sub {
	my ($string, $what, $where, $count) = @_;
	my (%id, $percent, $barlen, $pid, $name, $sh, $i, $x, $y);

	%id = id3($where, $what);

	$what =~ s/^\s//;
	$what =~ s/\s$//;
	
	$name = $where;
	$name =~ s/.*\/(.*)/\1/;

	print $OUT "\tPlaying MPEG stream from $name ...\n";
	print $OUT "\t\tTitle:\t$id{'title'}\n";
	print $OUT "\t\tArtist:\t$id{'artist'}\n\n";

	local $/ = "
";

	my ($sh) = "exec mpg123 -v $MPG123OPTS \"$where\" > $fifo 2>&1";

	my $mypid = fork();

	if ($mypid == 0) {
		system($sh);
		exit 0;
	}

	open (FIFO, "<$fifo");

	ReadMode 4; # Turn off controls keys

	while (<FIFO>) {
		if ($key = ReadKey(-1)) {
			last if ($key eq "n");
			&quit if ($key eq "q");
		}

		# Frame#   129 [19515], Time: 00:03.36 [08:29.77],
		next unless (/Frame.*Time:\s(\S\S):(\S\S)\.(\S\S)\s\[(\S\S):(\S\S)\.(\S\S)\].*/);

		unless (defined $i) {
			$y = $4.$5.$6;
			$i = 1;
		}

		$x = $1.$2.$3;
		
		$percent = 100.0 * $x / $y ;
		$barlen = $percent / 100.0 * $maxlen;

		printf "
\t\tDone:\t[%-".$maxlen."s] (%d%%)  ", "=" x $barlen, $percent;
	}

	ReadMode 0; # Reset tty mode before exiting

	kill 15, $mypid;
	wait;

	close (FIFO);
	print "\n\n";
};

$info = sub {
	my ($string, $what, $where, $count) = @_;

	$where =~ s/^\s//;
	$where =~ s/\s$//;

	my %id = id3($where, $what);

	print "\tTitle:\t $id{'title'}\n";
	print "\tArtist:\t $id{'artist'}\n";
	print "\tAlbum:\t $id{'album'}\n";
	print "\tYear:\t $id{'year'}\n";
	print "\tComment: $id{'comment'}\n";
	print "\tFile:\t $where\n\n";
};

while ( defined ($_ = $term->readline($prompt)) ) {
	$term->addhistory($_) if /\S/;
	if (/^q(?:uit)?/ or /^e(?:xit)?/) {
		print "Bye !\n";
		exit 0;
	} elsif (/^h(?:elp)?/) {
		help

	} elsif (/^c(?:lear)?/) {
		system("clear");

	} elsif (/^p(?:lay)?\s(.*)/) {
		step $1, $play;
		
	} elsif (/^l(?:list)?\s(.*)/) {
		step $1, $list;
		
	} elsif (/^i(?:nfo)?\s(.*)/) {
		step $1, $info;

	} elsif (/^a(?:dd)?\s(.*)/) {
		print $OUT "Adding directory $1 to index\n";
		&find($1);

	} elsif (/^d(?:rop)?/) {
		print $OUT "Dropping index\n";
		untie %playlist_ba;
		untie %playlist_bn;
		unlink $ba_file;
		unlink $bn_file;
		$ba_h = tie %playlist_ba, "DB_File", $ba_file, O_RDWR|O_CREAT, 0640, $DB_BTREE;
		$bn_h = tie %playlist_bn, "DB_File", $bn_file, O_RDWR|O_CREAT, 0640, $DB_BTREE;
	}
}


sub quit {
	ReadMode 0;
	untie %playlist_ba;
	untie %playlist_bn;

	unlink $fifo;

	system ("rm -f /tmp/*.$ext");
	system ("clear");
	exit;
}

__END__

=head1 NAME

mp3shell - A shell like interface to mpg123 and id3 tags

=head1 SYNOPSIS

B<mp3shell> C<[ -c F<directory> ]>

=head1 DESCRIPTION

B<mp3shell> allows you to manage and hear your mp3s comfortably
using a shell like interface.

The first time you use B<mp3shell>, you should invoke it with the
C<-c> switch.

B<mp3shell> gives you a shell prompt, where you can type in the following commands:

=over 4

=item C<list /expr/>

Lists all mp3s, whiches filename and/or author and group id3 tag
contains perl regular expression C</expr/>.


=item C<info /expr/>

Shows infos (id3 tags and filename) about files matching C</expr/>.


=item C<play /expr/>

Plays all files matching C</expr/>.
If you press 'n' while playing a mp3, B<mp3shell> makes you jump to the next file.
Pressing 'p' will exit mp3shell.


=item C<add /dir/>

Adds the directory beetween the two slashes to your index.


=item C<drop>

Drops your index.


=item C<clear>

Clears your screen.


=item C<help>

Gives you an useless help screen.


=item C<quit>

Exits mp3shell.


=item C<exit>

Same as quit.


=back

You can shorten all command to their first character.
You can leave away the slashes surrounding C<expr>.
These are not bugs, but features ;)

=head1 OPTIONS

=over 4

=item C<-c F<directory>>

Create an index by searching for mp3s in F<directory> and its subdirs.

=back

=head1 AUTHOR

Christoph Hellwig I<schch@pe.tu-clausthal.de>

=head1 THANKS

=over 4

=item 'Optonic' aka Kristof Korwisi I<kk@harry.quarzen.de>

For beta testing C<mp3shell> and setting up the
website (http://www.quarzen.de/mp3shell/).

=item Michael Hipp I<hippm@informatik.uni-tuebingen.de>

For coding mpg123, the best mp3 player on earth.


=back

=head1 TODO

=over 4

=item http streaming 

=item napster support ?

=item automatic ftp downloads ?

=back