MODULE DE CRYPTOGRAPHIE

#!/usr/bin/python
# -*- coding: iso8859-1 -*- 

''' 
	Module d'encodage & decodage
	Jule Cesar & Carrer de Viginaire
	Coded by Marnage 

Usage : 
	
from crypto import encode,decode

e = encode("cesar",1,"aA Bb Cc Yy Zz 09 ?!")
print e

e = decode("cesar",1,e)
print e


e = encode("viginaire",123,"aA Bb Cc Yy Zz 09 ?!")
print e

e = decode("viginaire",123,e)
print e

'''

from sys import stdout,exit

__all__ = "encode,decode"

class Variable:
	def __init__(self,txt,key):
		self.txt = txt
		self.key = key
		self.txt_crypt = ""
		self.txt_decrypt = ""
		if (type(key) != int ):
			try: self.key = int(key)
			except :
				 stdout.write("[!] Erreur : key != type int , conversion impossible\n")
				 exit(0)
		if (type(txt) != str ):
			try: self.key = str(key)
			except :
				 stdout.write("[!] Erreur : texte != type char , conversion impossible\n")
				 exit(0)
		

class Cesar(Variable):
	def __init__(self,txt,key):
		Variable.__init__(self,txt,key)

	
	def Encode(self):
		i = 0
		while ( i < len(self.txt) ):
			num = ord(self.txt[i])+self.key
			self.txt_crypt += chr(num)
			i += 1

	def Decode(self):
		i = 0
		while ( i < len(self.txt) ):
			num = ord(self.txt[i])-self.key
			self.txt_decrypt += chr(num)
			i += 1

class Viginaire(Variable):
	def __init__(self,txt,key):
		Variable.__init__(self,txt,key)
	
	def Encode(self):
		i = 0
		i_key = 0
		while ( i < len(self.txt) ):
			if ( i_key == len(str(self.key)) ):
				i_key = 0
			num = ord(self.txt[i])
			char_key = str(self.key)
			buffer_key = char_key[i_key]
			num += int(buffer_key)
			self.txt_crypt += chr(num)
			i += 1
			i_key += 1

	def Decode(self):
		i = 0
		i_key = 0
		while ( i < len(self.txt) ):
			if ( i_key == len(str(self.key)) ):
				i_key = 0
			num = ord(self.txt[i])
			char_key = str(self.key)
			buffer_key = char_key[i_key]
			num -= int(buffer_key)
			self.txt_decrypt += chr(num)
			i += 1
			i_key += 1

def encode(typ,key,txt):
	if ( typ == "cesar" ):
		Class = Cesar(txt,key)
		Class.Encode()
	elif ( typ == "viginaire" ):
		Class = Viginaire(txt,key)
		Class.Encode()
	else :
		return "[!] argument inconnu !"
	return Class.txt_crypt


def decode(typ,key,txt):
	if ( typ == "cesar" ):
		Class = Cesar(txt,key)
		Class.Decode()
	elif ( typ == "viginaire" ):
		Class = Viginaire(txt,key)
		Class.Decode()
	else :
		return "[!] argument inconnu" 
	return Class.txt_decrypt