convflac

#!/usr/bin/perl
# Usage: convflac <filename.flac> [fileout.m4a] [faac options]

#use common::sense;

# This is for meta data. Sometimes flac and m4a don't match up - e.g. tracknumber in flac
# and track in m4a. Specify them here. I don't really know all of them, so add as I go!
#
# One constraint: keep them lower case.
#our %mutation_map = (
#	#flac			#m4a
#	'tracknumber',		'track',
#	'notes',		'comment',
#	'date',			'year', # comment this line out if it's breaking stuff!
#);

# Some global variables:
our $infile, our $outfile, our $faac_options = ' ', our %mutation_map, our %settings;

# Check we have required programs
checkfaacflac();

# Read settings:
read_settings();

# If we have no arguments, show usage
noinfileerror() if ($#ARGV) == -1;

# grab input file from stdin
our $infile = $ARGV[0];
# basic error checking (if it's empty somehow or if it doesn't exist)
noinfileerror() if ($infile eq '');
filenotexisterror() if (!-e $infile);

# Just one argument, so derive the name of the output file
if ($#ARGV == 0) {
	$outfile = $infile;
	$outfile =~ s/\.flac$/.m4a/i;
	if ($outfile !~ /\.m4a$/) {
		$outfile .= '.m4a';
		print 'Warning - input file does not end in .flac, outputting to '.$outfile."\n";
	}
}
elsif ($#ARGV >= 1) {
	$outfile = $ARGV[1];

	if ($#ARGV > 1) {
		for (my $i = 2; $i <= $#ARGV; $i++) {
			$faac_options .= $ARGV[$i].' ';
		}
	}
}

convert();

sub convert {
	print 'Converting "'.$infile.'" to "'.$outfile.'"'."\n";
	#Get meta data
	my $meta = metadata();
	# Construct command:
	# Default:
	my $cmd = 'flac ';
	if ($settings{'codec_flac'} ne '') {
		$cmd .= $settings{'codec_flac'};
	}
	else {
		$cmd .= '-cd';
	}

	$cmd .= ' "'.$infile.'" | faac ';

	if ($settings{'codec_faac'} ne '') {
		$cmd .= $settings{'codec_faac'};	
	}
	else {
		$cmd .= '-q 300 -w -s '.$faac_options;
	}
	$cmd .= ' '.$meta.' -o "'.$outfile.'" -';

	print "\n".'Executing: '.$cmd."\n";
	my $output = `$cmd >/dev/null`;
	print 'done'."\n";
}

sub metadata {
	print 'Obtaining meta data...'."\n";
	my $metaout = '';
	# Tags supported by faac as far as I know
	my $unsupported = '';
	my @supported = (
		'artist',
		'writer',
		'title',
		'genre',
		'album',
		'track',
		'disc',
		'year',
		'comment',
	);
	#Use metaflac to grab file info
	my $metadata = `metaflac --export-tags-to=- "$infile"`;
	my @metatable = split(/\n/, $metadata);
	foreach (@metatable) {
		chomp;
		my $found = 0;
		my ($key, $value) = split(/=/);
		# Lower case key
		$key =~ tr/[A-Z]/[a-z]/;
		if ($mutation_map{$key} ne '') {
			print $key.' => ';
			$key = $mutation_map{$key};
		}
		foreach (@supported) {
			if ($_ eq $key) {
				$metaout .= '--'.$key.' "'.$value.'" ';
				print $key."\t=\t".$value."\n";
				$found = 1;
			}
		}
		if ($found == 0) {
			$unsupported .= $key.', ';
		}
	}
	if ($unsupported ne '') {
		print 'Unsupported tags: '.$unsupported."\n";
	}
	return $metaout;
}

sub noinfileerror {
	print 'No input flac file'."\n\n";
	showusage();
}

sub filenotexisterror {
	print 'Input file '.$infile.' not found'."\n\n";
	showusage();
}

sub showusage {
	print 'Usage: convflac <filein.flac> [fileout.m4a]'."\n";
	print 'If no fileout is specified, then filein.m4a will be created'."\n";
	exit;
}

sub checkfaacflac {
	my @apps = (
		'flac',
		'metaflac',
		'faac',
	);
	foreach (@apps) {
		if (checkapp($_) == 0) {
			print 'Error: Cannot find "'.$_.'" in your path. Please install it and try again.'."\n";
			exit(-1);
		}
	}
	return;
}
sub checkapp {
	my $app = shift;
	my @path = split(/:/, $ENV{'PATH'});
	foreach (@path) {
		return 1 if (-e $_.'/'.$app);
	}
	return 0;
}

sub read_settings {
	my $home = $ENV{'HOME'};
	my $settings = $home.'/.convflac';
	if (!-e $settings) {
		return if (create_settings() == -1);
	}
	open(FHANDLE, $settings) or return -1;
	foreach (<FHANDLE>) {
		if ((!/^#/) and (/=/)) {
			my @args = split(/=/), my $key, my $value = $_;
			$key = $args[0];
			$value =~ s/^$key=(.*?)/\1/i;
			$value =~ s/^\s(.*?)/\1/i;
			$key =~ tr/[A-Z]/[a-z]/;
			$key =~ s/\s$//;
			chomp($key);
			chomp($value);
			if ($key !~ /^mutation_/) {
				$settings{$key} = $value;
			}
			else {
				$key =~ s/^mutation_(.*?)/\1/i;
				$mutation_map{$key} = $value;
			}
		}
	}
	close(FHANDLE);
	
}

sub create_settings {
	open(FHANDLE, '>'.$ENV{'HOME'}.'/.convflac') or return -1;
	print FHANDLE '# convflac config file'."\n";
	print FHANDLE '# lines starting with # are comments, everything else is key=value'."\n\n";
	print FHANDLE '# Codec options - uncomment to make changes to quality settings'."\n";
	print FHANDLE '# Default is -q 300 -w -s for faac, it\'s recommended you leave flac alone'."\n";
	print FHANDLE '# See man flac and man faac for more info'."\n";
	print FHANDLE '#codec_faac = -q 300 -w -s'."\n";
	print FHANDLE '#codec_flac = -cd'."\n\n";
	print FHANDLE '# Mutation options (for tags):'."\n";
	print FHANDLE '#mutation_flacname = faacname'."\n";
	print FHANDLE 'mutation_tracknumber = track'."\n";
	print FHANDLE 'mutation_notes = comment'."\n";
	print FHANDLE 'mutation_date = year'."\n\n";
	close(FH);
}