#--------------------------------------------------------------------------
# Name:          liars_bingo
# Purpose:       Implementation of algorithm for generating cards used in
#                Liar's Bingo.
#
# Author:        Nicholas Bennett
#
# Last modified: 2017-01-29
# Copyright:     (c) Nicholas Bennett 2017
# Licence:       Creative Commons Attribution-ShareAlike 4.0 International 
#                License http://creativecommons.org/licenses/by-sa/4.0/
#--------------------------------------------------------------------------


DEFAULT_BITS_PER_DIGIT = 3
DEFAULT_DIGITS_PER_CARD = 2
DEFAULT_BITS_PER_CARD = DEFAULT_BITS_PER_DIGIT * DEFAULT_DIGITS_PER_CARD
DEFAULT_DIGIT_CHARS = '0123456789abcdef'


def str_radix(value,
              radix_bits=DEFAULT_BITS_PER_DIGIT,
              digit_chars=DEFAULT_DIGIT_CHARS,
              least_significant=True):
    if (value == 0):
        if (least_significant):
            return '0'
        else:
            return ''
    return (
        str_radix(value >> radix_bits, radix_bits, digit_chars, False)
        + digit_chars[value & ((1 << radix_bits) - 1)]
    )


def generate(bits_per_card=DEFAULT_BITS_PER_CARD):
    return [
        [
             card_index ^ (1 << col_index)
             for col_index in range(bits_per_card - 1, -1, -1)
        ]
        for card_index in range(1 << bits_per_card)
    ]


def stringify(cards,
              bits_per_card=DEFAULT_BITS_PER_CARD,
              bits_per_digit=DEFAULT_BITS_PER_DIGIT,
              digit_chars=DEFAULT_DIGIT_CHARS):
    return "\n".join(
        " ".join(
            "{0:>2}{1}".format(
                str_radix(cards[i][j], bits_per_digit, digit_chars),
                "R" if (i & (1 << (bits_per_card - j - 1))) else "B"
            )
            for j in range(bits_per_card)
        )
        for i in range(1 << bits_per_card)
    )


if __name__ == '__main__':
    print(stringify(generate()))