#!/usr/bin/perl

use Audio::Wav;

($cfg{file}) = @ARGV;

my ($right,$left) = $cfg{file} =~ m!tape([^-]+)-([^\.]+)\.wav!;

die "couldn't figure out left and right\n" unless ($left && $right);

my $wav = Audio::Wav->new;
my $in = $wav->read($cfg{file});

$cfg{details} = {
	channels	=> 1,
	bits_sample	=> 16,
	sample_rate	=> 44100,
};

my $l = $wav->write("tape".$left.".wav",$cfg{details});
my $r = $wav->write("tape".$right.".wav",$cfg{details});

my $sub;
for (my $x = 0;$x <= 4800;$x+=4) {
	$sub .= qq(\$ld .= substr(\$d,$x,2);\$rd .= substr(\$d,$x+2,2););
}

my $sref = eval "sub { my \$d = shift; my (\$ld,\$rd); $sub return (\$ld,\$rd);}";
warn "eval error: $@\n" if ($@);

while (my $d = $in->read_raw(4800)) {

	my ($ld,$rd) = &$sref($d);

#	my ($ld,$rd);
#	for (my $x = 0;$x <= 1200;$x+=12) {
#		$ld .= substr($d,$x,2);
#		$rd .= substr($d,$x+2,2);
#		$ld .= substr($d,$x+4,2);
#		$rd .= substr($d,$x+6,2);
#		$ld .= substr($d,$x+8,2);
#		$rd .= substr($d,$x+10,2);
#	}

	$l->write_raw($ld);
	$r->write_raw($rd);
}

$l->finish;
$r->finish;