# -*- coding: UTF-8 -*-

"""Keyboard-Shift Codec - keyboard line shifting content encoding.

This codec:

- en/decodes strings from str to str

- en/decodes strings from bytes to bytes

- decodes file content to str (read)

- encodes file content from str to bytes (write)

"""

from ..__common__ import *

LAYOUTS = {

'ansi': "~!@#$%^&*()_+\n`1234567890-=\nqwertyuiop{}|\n[]\\\nasdfghjkl:\"\n;'\nzxcvbnm<>\n,./",

'azerty': "azertyuiop\nqsdfghjklm\nwxcvbn",

'azerty-be': "³1234567890°_\n²&é\"'(§è!çà)-\n|@#^{}\nazertyuiop$\n€[]\n¨*\nqsdfghjklm%£\nùµ\n´`\n>wxcvbn?./+\n<,;:=\n\\~",

'azerty-fr': "1234567890°+\n²&é\"'(-è_çà)=\n~#{[|`\\^@]}\nazertyuiop¨£\nqsdfghjklm%µ\nù*\n>wxcvbn?./§\n<,;:!",

'dvorak': "~!@#$%^&*(){}\n`1234567890[]\n\"<>pyfgcrl?+|\n',./=\\\naoeuidhtns_\n-\n:qjkxbmwvz\n;",

'qwerty': "qwertyuiop\nasdfghjkl\nzxcvbnm",

'qwerty-us': "~!@#$%^&*()_+\n`1234567890-=\nqwertyuiop{}|\n[]\\\nasdfghjkl:\"\n;,\nzxcvbnm<>?\n./",

}

__per_len = {}

for k, s in LAYOUTS.items():

i = max(map(len, s.split("\n")))

__per_len.setdefault(i, [])

__per_len[i].append(k)

__examples__ = {"enc-dec(kbshift_%s_%d)" % (kb, n): ["@irandom{256,512}"] for n in range(10) for kb in LAYOUTS.keys()}

__guess__ = []

for mlen, kbs in __per_len.items():

for k in kbs:

__guess__.extend(["kbshift-%s-%d" % (k, i+1) for i in range(mlen)])

def _kbshift(text, keyboard="azerty", n=1, decode=False):

r = ""

for c in text:

nc = None

for l in LAYOUTS[keyboard].splitlines():

if c.lower() in l:

nc = l[(l.index(c.lower()) + [-1, 1][decode] * n) % len(l)]

break

r += c if nc is None else nc

return r

def kbshift_encode(scheme):

kb, shift = re.match(r"^(.*?)[-_]?(\d+)$", scheme or "azerty-1").groups()

def encode(text, errors="strict"):

r = _kbshift(ensure_str(text), kb, int(shift))

return r, len(r)

return encode

def kbshift_decode(scheme):

kb, shift = re.match(r"^(.*?)[-_]?(\d+)$", scheme or "azerty-1").groups()

def decode(text, errors="strict"):

r = _kbshift(ensure_str(text), kb, int(shift), True)

return r, len(r)

return decode

add("kbshift", kbshift_encode, kbshift_decode, entropy=lambda e: e,printables_rate=lambda pr: pr, transitive=True,

pattern=r"^kbshift(?:|[-_]((?:az|qw)erty[-_]?[1-9]|(?:ansi|azerty-(?:be|fr)|dvorak|qwerty-us)[-_]?(?:[1-9]|1[0-2])))$")