# coding=utf-8
from random import *
import qwerty
from math import *
import time


def gcd(a, b):
    """returns the Greatest Common Divisor of a and b"""
    a = abs(a)
    b = abs(b)
    if a < b:
        a, b = b, a
    while b != 0:
        a, b = b, a % b
    return a


def int_base_two(x):
    """x is a positive integer. Convert it to base two as a list of integers
    in reverse order as a list."""
    # repeating x >>= 1 and x & 1 will do the trick
    bit_inverse = []
    while x != 0:
        bit_inverse.append(x & 1)
        x >>= 1
    return bit_inverse


def mod_exp(a, d, n):
    """returns a ** d (mod n)"""
    base_two_d = int_base_two(d)
    base_two_d__len = len(base_two_d)
    mod_array = []
    result = 1
    for i in range(1, base_two_d__len + 1):
        if i == 1:
            mod_array.append(a % n)
        else:
            mod_array.append((mod_array[i - 2] ** 2) % n)
    for i in range(0, base_two_d__len):
        if base_two_d[i] == 1:
            result *= base_two_d[i] * mod_array[i]
    return result % n


def to_bin(x):
    return bin(x)[2:]


def to_bin_8(x):
    return bin(x)[2:].zfill(8)


def data_to_bin_str(data_file):
    bin_str = ''
    for i in data_file:
        bin_str += (to_bin_8(ord(i)))
    return bin_str


def encrypt(file, e_file, open_key, N):

    f = open(file, 'rb')
    f.seek(0)
    data_file = f.read()
    fi = open(e_file, 'wb')
    #print data_file
    for i in range(0, len(data_file), 64):
        part_of_data_file = data_file[i:i+64]

        bin_str = data_to_bin_str(part_of_data_file)

        num_str = int(bin_str, 2)
        #print num_str

        secret_num = str(mod_exp(num_str, int(open_key), int(N)))
        fi.write(str(secret_num + '\n'))

    fi.close()
    f.close()


def decrypt(d_file_en, d_file_dec, secret_key, N):
    f = open(d_file_en, 'rb')
    fi = open(d_file_dec, 'wb')

    for line in f:
        l = line.strip()

        secret_mes = mod_exp(int(l), secret_key, N)

        tmp = secret_mes
        string = ''
        while tmp:
            string += chr(tmp & 0b11111111)
            tmp >>= 8
        #print '\n', string[::-1]

        fi.write(string[::-1])
    f.close()
    fi.close()


def multiple_inv(e, F):
    u = (e, 1)
    v = (F, 0)
    while v[0] != 0:
        q = u[0] // v[0]
        t = (u[0] % v[0], u[1] - q * v[1])
        u = v
        v = t
    if u[0] != 1:
        return 0
    return u[1] % F


time.clock()
p = qwerty.findAPrime(10**154, 2**512-1, 50)
q = qwerty.findAPrime(10**154, 2**512-1, 50)
#print p, q
print time.clock()

#p = 3484012459357535389257764733341658573348123528084503236095329120219032291822016457428603267715402056283756173357918283509919929164000482319465122237816683
#q = 650596054740854964979315968687627705877635108044267532891060878406152879074939666218121009645274892558211324045903927901263695872711186043763777008229087
F = (p-1)*(q-1)
N = p*q

secret_key = multiple_inv(123426017006182806728593424683999798008235734137469123231828679 , F)
encrypt("data_file.txt", "data_file_encrypt", 123426017006182806728593424683999798008235734137469123231828679 , N)
decrypt("data_file_encrypt", "data_file_decrypt.txt", secret_key, N)