#has user enter keyword and message, checks to see if input has two strings
def checkString ():
    usermsg = input ("Enter keyword and message to be encrypted, separated by a space: ")
    string = usermsg.split()
    messageList = []
    #each object converted to uppercase, puts into empty list
    for Object in string:
        hello = Object.upper ()
        messageList.append (hello)

    twostring = len(messageList)
    if twostring != 2:
        print ("ERROR")
    else:
        duplicateLetter(messageList)


#checks and removes duplicate letters and non-alphabet characters, converts X to K & S
def duplicateLetter (messageList):
    alphabet = "ABCDEFGHIJKSLMNOPQRTUVWXYZ"
    newInput = []
    newStr = ""
    keyword = messageList
    for obj in keyword:
        for ch in obj:
            if ch == "X":
                ch = "KS"
            if ch in alphabet:
                if ch not in newStr:
                    newStr = newStr + ch
        newInput.append (newStr)
        newStr = ""
    createAlphaTable (newInput)
    #EvenOdd (newInput,table)

#takes result of duplicateLetter and puts it into a new string with the rest of the alphabet #creates table in the format of playfair cipher
def createAlphaTable (newInput):
    alphabet = "ABCDEFGHIJKLMNOPQRSTUVWYZ"
    alphaKey = ""
    keyword = newInput [0]
    for ch in alphabet:
        if ch not in keyword:
            alphaKey = alphaKey + ch
    cipherKey = keyword + alphaKey
    print (cipherKey)
    #createTable (cipherKey)

#creates table in the format of playfair cipher
    table = [cipherKey[i:i+5] for i in range(0, len(cipherKey), 5)]
    print (table)
    #return table
    EvenOdd (newInput,table)

# determines the length of the message to be encrypted. if odd, adds 'Z' to the end of the string. if even, continues to next function without change
def EvenOdd (newInput,table):
    message = newInput [1]

    if (len(message) % 2 == 0):
        tobeEncrypt (message,table)
    else:
        message = message + 'Z'
        tobeEncrypt (message,table)

#splits the message (2nd inputted word) into pairs and adds a 'Z' at the end of the pair if only containing 1 character, moves pairs into empty list
def tobeEncrypt(message,table):
    pairList = []
    letterPair = ""
    for ch in message:
        if len(letterPair) != 2:
            letterPair = letterPair + ch
        if len(letterPair) == 2:
            pairList.append (letterPair)
            letterPair = ""
    print (pairList)
    encryptPair(pairList,table)

def encryptPair(pairList,table):
    rowPos = []
    colPos = []

    row = 0
    col = 0
    i = 0
    q  = 0
    for eachPair in pairList:
        for letter in eachPair:
            while i <= 4:
                if letter in table[i] :
                    row = i
                    break
                else:
                    i = i + 1
            while q <= 4:
                if letter in table [row][q]:
                    col = q
                    break
                else:
                    q = q + 1
            rowPos.append(row)
            colPos.append(col)
            i = 0
            q = 0
    #print (rowPos, colPos)

    posList = []
    posPair = ""
    for num in rowPos:
        if len(posPair) != 2:
            posPair = str(num) + str(colPos[i])
            i = i + 1
        if len(posPair) == 2:
            posList.append (posPair)
            posPair = ""
    print (posList)
    convLetter(posList,table)

def convLetter (posList,table):
    encryptPair  = []
    onePair = ""
    twoPair = ""
    d = 0
    w = 0
    q = 1
    for pair in posList:
        pair1 = posList [d][w]
        pair2 = posList [q][w]
        onechar = pair [0]
        twochar = pair [1]
        if pair1 == pair2:
            if int(twochar) == 4:
                twochar = 0
                onePair = onechar + str(twochar)
                twoPair = onechar + str(int(posList [d+1][w+1]) + 1)
                #d = d + 1
            else:
                twochar = int(twochar) + 1
                onePair = onechar + str(twochar)
                twoPair = onechar + str(int(posList [d+1][w+1]) + 1)
            encryptPair.append (onePair)
            encryptPair.append (twoPair)
            onePair = ""
            print(twoPair)
            twoPair = ""
        if q != (len(posList)-2):
            d = d + 1
            q = q + 1
        #print (type(posList [d+1][w+1]))
        ##w =
        ##elif posList [d][w] == posList [d][w]:
            ##for item in pair:
    #break
    print ((len(posList)-2))
    print (encryptPair)

checkString ()