# -*- coding: utf-8 -*-

from __future__ import division

import random

from django_response import response
from logit import logit

from mch.models import BrandInfo, ModelImageInfo, ModelInfo
from utils.algorithm.b64 import b64_decrypt, b64_encrypt
from utils.algorithm.caesar import caesar_decrypt, caesar_encrypt
from utils.algorithm.rsalg import rsa_decrypt, rsa_encrypt


# CIPHER_ALGORITHM = ('CAESAR', 'B64', 'RSA')
CIPHER_ALGORITHM = ('CAESAR', )

CIPHER_PREFIX = {
    'CAESAR': '0',
    'B64': '1',
    'RSA': '2',
}


@logit(res=True)
def encrypt(request):
    plaintext = request.POST.get('plaintext', '')

    alg = random.choice(CIPHER_ALGORITHM)

    if alg == 'CAESAR':
        ciphertext = caesar_encrypt(plaintext)
    elif alg == 'B64':
        ciphertext = b64_encrypt(plaintext)
    elif alg == 'RSA':
        ciphertext = rsa_encrypt(plaintext)
    else:
        ciphertext = plaintext

    return response(200, data={
        'ciphertext': u'{prefix}+{cipherlen}+{ciphertext}'.format(
            prefix=CIPHER_PREFIX.get(alg, ''),
            cipherlen=len(ciphertext),
            ciphertext=ciphertext,
        ),
    })


@logit(res=True)
def decrypt(request):
    ciphertext = request.POST.get('ciphertext', '')

    prefix, cipherlen, ciphertext = ciphertext.split('+', 2)

    ciphertext = ciphertext[:int(cipherlen)]

    if prefix == CIPHER_PREFIX['CAESAR']:
        plaintext = caesar_decrypt(ciphertext)
    elif prefix == CIPHER_PREFIX['B64']:
        plaintext = b64_decrypt(ciphertext)
    elif prefix == CIPHER_PREFIX['RSA']:
        plaintext = rsa_decrypt(ciphertext)
    else:
        plaintext = ciphertext

    # brand_id#model_id#distributor_id#sn#time
    # AAAA#AAAAAA#AAAAA#AAAAAAAAAAAAAA#180224
    brand_pk, model_pk, distributor_pk, sn, time = plaintext.split('#')

    try:
        brand = BrandInfo.objects.get(pk=brand_pk)
    except BrandInfo.DoesNotExist:
        brand = None

    try:
        model = ModelInfo.objects.get(pk=model_pk)
    except ModelInfo.DoesNotExist:
        model = None

    return response(200, data={
        'plaintext': plaintext,
        'logo_url': brand.brand_logo_url if brand else '',
        'model_imgs': model.images if model else [],
        'goodsInfo': {
            'Brand': brand.brand_name if brand else '',
            'Model': model.model_name if model else '',
            'SerialNo': sn,
        }
    })