Playfair Cipher Algorithm (E).py

from collections import OrderedDict 

def Generate_Pairs():
	i=0
	while i != len(plainText_lis):
		if(i == (len(plainText_lis)-(len(plainText_lis)%2)) and len(plainText_lis)%2 != 0):
			plainText_lis.append('x')
			break
		if(plainText_lis[i]==plainText_lis[i+1]):
			plainText_lis.insert(i+1,'x')
		i+=2

	Key_Matrix()

def Key_Matrix():
	key_lis_tmp.extend(key_dup)

	var=0
	
	while len(key_lis_tmp)!=25:
		value = chr(97+var)
		if value not in key_lis_tmp:
			if value != 'j':
				key_lis_tmp.append(value)
		var+=1

	for i in range(0,len(key_lis_tmp),5):
		matrix_pf.append(key_lis_tmp[i:i+5])

	print("\nMatrix: ")
	for i in matrix_pf:
		print(i,end="\n")

	Playfair_Cypher_Algo()

def Fetch_Inde(valu_fn):
	for index_one_fe,i in enumerate(matrix_pf):
		for index_two_fe,j in enumerate(i):
			if j == valu_fn:
				return(index_one_fe,index_two_fe)

def Playfair_Cypher_Algo():
	for i in range(0,len(plainText_lis)-1,2):
		index_one_pf,index_two_pf = Fetch_Inde(plainText_lis[i])
		index_three_pf,index_four_pf = Fetch_Inde(plainText_lis[i+1])
		
		if (index_one_pf == index_three_pf):
			index_two_pf = (index_two_pf+1)%5
			index_four_pf = (index_four_pf+1)%5
			cipherText.extend(matrix_pf[index_one_pf][index_two_pf])
			cipherText.extend(matrix_pf[index_three_pf][index_four_pf])

		elif(index_two_pf == index_four_pf):
			index_one_pf = (index_one_pf+1)%5
			index_three_pf = (index_three_pf+1)%5
			cipherText.extend(matrix_pf[index_one_pf][index_two_pf])
			cipherText.extend(matrix_pf[index_three_pf][index_four_pf])
		
		else:
			cipherText.extend(matrix_pf[index_one_pf][index_four_pf])
			cipherText.extend(matrix_pf[index_three_pf][index_two_pf])

	print("\nCipher Text: ","".join(cipherText))


plainText = input("\nEnter Plain Text: ")
key = input("Enter Key: ")

plainText = plainText.replace(" ","").lower()
plainText = plainText.replace("j","i")
key = key.replace(" ","").lower()
key = key.replace("j","i")

key_dup="".join(OrderedDict.fromkeys(key))

plainText_lis=list(plainText)
matrix_pf = []
key_lis_tmp = []
cipherText = []

Generate_Pairs()