#!/usr/bin/env python

###################################################################

#### Merchant program taking an invoice and a signed check ####

#### as a parameter and checking if the client didn't edit ####

#### the invoice and that the check is correct ####

#### Arguments : - invoice file ####

#### - signed check ####

#### Output : Either that the check is fine or not ####

###################################################################

import sys

from facture import Facture

from fileUtils import FileUtils

from RSAtools import RSAtools

if( len(sys.argv) < 4 ):

print("You need to put all of the arguments (invoice file, signed check and client's Pk)")

sys.exit()

# file opening

try:

invoice_file = open(sys.argv[1], 'r')

signedcheck_file = open(sys.argv[2], 'r')

except (OSError, IOError) as error:

print("Error reading file : ", error)

sys.exit()

fileutils = FileUtils()

rsatools = RSAtools()

#Getting the infos from the files

clepub_client = fileutils.recupKey(sys.argv[3])

facture = Facture(sys.argv[1])

clepub_merchant_original = fileutils.recupKey("commercantPk")

bankPk = fileutils.recupKey("banquePk")

merchantkeyclientciphered = []

clientkeybanqueciphered = []

merchantkeyclientciphered.append( fileutils.readKey(sys.argv[2],0))

merchantkeyclientciphered.append( fileutils.readKey(sys.argv[2],1))

clientkeybanqueciphered.append(fileutils.readKey(sys.argv[2],2))

clientkeybanqueciphered.append(fileutils.readKey(sys.argv[2],3))

uid_ciphered = fileutils.readKey(sys.argv[2],4)

sum_ciphered = fileutils.readKey(sys.argv[2],5)

clepub_client = [rsatools.decryptblock(bankPk, clientkeybanqueciphered[0]), rsatools.decryptblock(bankPk, clientkeybanqueciphered[1])]

clepub_merchant = [rsatools.decryptblock( clepub_client, merchantkeyclientciphered[0]), rsatools.decryptblock( clepub_client, merchantkeyclientciphered[1])]

#Decyphering the cypher of the sum and of the id by the client

uid_clear = rsatools.decryptblock(clepub_client, uid_ciphered)

sum_clear = rsatools.decryptblock(clepub_client, sum_ciphered)

#Checking if they are the same than the one on the invoice

if(uid_clear != facture.getUid()):

print("Elements différents lors de la vérification (UID de la facture)")

if(sum_clear != facture.getTotalSomme()):

print("Elements différents lors de la vérification (Somme totale de la facture)")

#checking if the merchant's public key ciphered by the client is right

if(clepub_merchant != clepub_merchant_original):

print("Elements différents lors de la vérification (clée du marchant chiffrée par le client)")