Decryption program for the game Twisty Destiny.

dec.py

import os, sys
import StringIO
import time
import pdb

### init some paths
ScriptPath = os.path.abspath(__file__)
ScriptDir = os.path.dirname(ScriptPath)
InputDir = os.path.join(ScriptDir, "data")
OutputDir = os.path.join(ScriptDir, "decrypted")

def decodes(data):
    c = 0
    for i in xrange(len(data)):
        byte = ord(data[i])
        if i % 2:
            yield byte ^ 0x39
        else:
            yield byte ^ 0x5B

def decode_stream(ins, outs):
    ss = StringIO.StringIO()
    [ss.write(chr(i)) for i in decodes(ins.read())]
    outs.write(ss.getvalue())

def mkdir(path):
    if not os.path.isdir(path):
        mkdir(os.path.dirname(path))
        os.mkdir(path)

def decrypt_file(infile):
    print "Processing %s..." % infile

    segs = infile.split('\\')[0:-1]
    segs[2] = 'decrypted'
    outpath = '\\'.join(segs)

    if not os.path.isdir(outpath):
        mkdir(outpath)
    outfile = os.path.join(outpath, os.path.basename(infile))

    t1 = time.time()
    with open(infile, "rb") as inf:
        with open(outfile, "wb") as outf:
            decode_stream(inf, outf)
    t2 = time.time()
    elapsed = t2 - t1

    print "\tOK. Time elapsed: %.3f secs" % elapsed

def decrypt_dir(dir):
    dir = os.path.abspath(dir)
    if not os.path.isdir(dir):
        return

    print "Enter directory %s..." % dir
    for ent in os.listdir(dir):
        ent_path = os.path.join(dir, ent)
        if os.path.isfile(ent_path):
            decrypt_file(ent_path)
        elif os.path.isdir(ent_path):
            decrypt_dir(ent_path)
        else:
            print "ERROR: " + ent_path

def main():
    decrypt_dir(InputDir)

if __name__ == '__main__':
    main()