#!/usr/bin/env ruby

# Nasty little Core OS pkg unpacker
# By Anomaly, NYE 2010/2011

if (ARGV[0] == "") || (ARGV[0] == nil)
  puts "usage: #{$0} "
  exit
end

fd = open(ARGV[0],'r')
hdr = fd.read(4)
itemcount = fd.read(4).unpack('N')[0]
dummy = fd.read(4)
pkglen = fd.read(4).unpack('N')[0]

puts "pkg length:\t%d bytes" % pkglen
puts "items:\t\t%d\n\n" % itemcount

files = {}
for x in (1..itemcount)
  fd.read(4)
  offset = fd.read(4).unpack('N')[0]
  fd.read(4)
  len = fd.read(4).unpack('N')[0]
  fname = fd.read(32).strip
  files.update fname => [offset,len]
end

for file in files.keys
  puts "Filename: %s" % file
  puts "Offset: %d" % files[file][0]
  puts "Length: %d" % files[file][1]
  begin
    fd.seek(files[file][0],0)
    tmpfd = open(file,'w')
    tmpfd.write(fd.read(files[file][1]))
    tmpfd.flush()
    tmpfd.close()
    puts "write succeeded\n\n"
  rescue
    puts "write failed:"
    puts "#{$!}\n\n"
  end
end

fd.close()