btoh.py

from collections import namedtuple

Disk = namedtuple('Disk', ['size', 'colour'])


class BicolorTowersOfHanoi(object):
    def __init__(self, disks=3):
        self._disks = disks
        self._moves = 0
        self._towers = {1: [], 2: [], 3: []}
        self.reset()

    def reset(self):
        self._moves = 0
        self._towers[1] = [Disk(x + 1, 'black' if x & 1 else 'white') for x in reversed(range(self._disks))]
        self._towers[2] = [Disk(x + 1, 'white' if x & 1 else 'black') for x in reversed(range(self._disks))]
        self._towers[3] = []
        self._render()

    def move(self, from_, to):
        if from_ == to or from_ not in (1, 2, 3) or to not in (1, 2, 3):
            print('Invalid move!')
            return
        if len(self._towers[from_]) == 0:
            print('There are no more disks on that stack!')
            return
        if len(self._towers[to]) == 0 or self._towers[from_][-1].size <= self._towers[to][-1].size:
            self._towers[to].append(self._towers[from_].pop())
            self._moves += 1
            self._render()
        else:
            print("Can't move a larger disk onto a smaller disk!")

    def _render(self):
        width = self._disks * 4 - 1
        for i in reversed(range(self._disks * 2)):
            row = []
            for j in (1, 2, 3):
                try:
                    size = self._towers[j][i].size * 4 - 1
                    colour = self._towers[j][i].colour
                    symbol = 'X' if colour == 'black' else 'O'
                    row.append(str.center(symbol * size, width))
                except (IndexError, AttributeError):
                    row.append(str.center('|', width))
                    pass
            print('{}  {}  {}'.format(*row))
        print('Moves: {}'.format(self._moves))

        # win checking not working yet
        # if (len(self._towers[1]) == 0 or self._towers[1][0].colour != 'black') and (
        #         len(self._towers[2]) == 0 or self._towers[2][0] != 'white'):
        #     if {self._disks, self._disks, 0} == set(len(x) for x in self._towers.values()):
        #         win = 0
        #         for x in self._towers.values():
        #             if len(x) == 0:
        #                 win += 1
        #             elif set(y.colour for y in x) == set(x[0]):
        #                 win += 1
        #             if win == 2:
        #                 print('Congratulations! You won!')
        #                 break