#!/usr/bin/perl

use strict;
use warnings;
use IO::File;

sub usage() {
	print STDERR "Usage: unscramble SileadTouch.fw gsl_ts.fw\n";
	print STDERR "Converts a scrambled Silead Windows driver firmware image into legacy binary format.\n";
	-1;
}

my $scrfile = $ARGV[0] or exit usage;
my $fwfile = $ARGV[1] or exit usage;

my $scrambled = '';
do {
	my $in = IO::File->new($scrfile, 'r') or die "Can't open $scrfile: $!";
	$in->binmode();
	local $/;
	$scrambled = <$in>;
	defined $scrambled or die "Can't read firmware: $!";
	$in->close();
};

my $unscrambled = '';
for my $char (split //, $scrambled) {
	$unscrambled .= chr(ord($char) ^ 0x88);
}

my $out = IO::File->new($fwfile, 'w') or die "Can't open $fwfile: $!";

my $cfg = 0;
for my $line (split /\n/, $unscrambled) {
	if ($cfg and $line =~ /};/) {
		$cfg = 0;
	}
	if ($line =~ /TS_CFG_DATA/) {
		$cfg = 1;
	}
	if ($cfg) {
		$line =~ s/\s//g;
		$line = lc($line);
		if ($line =~ /{0x([0-9a-f]+),0x([0-9a-f]+)},/) {
			my $address = hex($1);
			my $data = hex($2);
			print $out pack('(LL)<', $address, $data) or die "Can't write to output: $!";;
		}
	}
}

$out->close();