#!/usr/bin/env python3
# -*- coding: utf8 -*-
test = "Hallo"
t1r2 = "rank the code"
t2r2 = "rn h oeaktecd"
t3r3 = "coding"
t4r3 = "cnoigd"
t5r3 = "rank the code"
t6r3 = "r  eaktecdnho"


def array_ausgabe(arri: list):
    for line in arri:
        print("".join(line))
    print()


def encrypt(plain_text: str, rails: int):
    arr = [["_" for _ in range(len(plain_text))] for _ in range(rails)]
    r = 0
    z = 0
    plus = True
    for b in plain_text:
        arr[r][z] = b
        z += 1
        if r + 1 == rails and plus:
            plus = False
            r -= 1
        elif r - 1 < 0 and not plus:
            plus = True
            r += 1
        elif plus:
            r += 1
        else:
            r -= 1
    out = ""
    for i in range(rails):
        for j in range(len(plain_text)):
            if arr[i][j] != "_":
                out += arr[i][j]
    print(out)
    array_ausgabe(arr)


def decrypt(cipher: str, rails: int):
    arr = [["_" for _ in range(len(cipher))] for _ in range(rails)]
    # cipher ins array reinbasteln
    x, y = 0, 0
    first_x = True
    for b in cipher:
        if x >= len(cipher) and y < rails:
            y += 1
            x = y
            first_x = True
        arr[y][x] = b
        if y == 0 or (first_x and y != rails-1):
            x = x + (rails - y - 1) * 2
            first_x = False
        elif y == rails-1 or first_x is False:
            x = x + (y * 2)
            first_x = True
    array_ausgabe(arr)
    # dekodierten Text aus array holen
    out = ""
    x, y = 0, 0
    down = True
    for i in range(len(cipher)):
        out += arr[y][x]
        x += 1
        if down and y+1 == rails:
            down = False
            y -= 1
        elif down:
            y += 1
        elif down is False and y == 0:
            down = True
            y += 1
        elif down is False:
            y -= 1
    print(out)


encrypt(t1r2, 2)
decrypt(t2r2, 2)
encrypt(t3r3, 3)
decrypt(t4r3, 3)
encrypt(t5r3, 3)
decrypt(t6r3, 3)