__author__ = 'jeff@bluebirdsol.com'


class Dir:
    To, From = 'To', 'From'

# Now with more closure goodness...
def make_negabase(base=-2):
    def negaverter(dir=Dir.To):
        def to_nega(i):
            digits = []
            if not i:
                digits = [0]
            else:
                while i != 0:
                    i, remainder = divmod(i, base)
                    if remainder < 0:
                        i, remainder = i + 1, remainder + abs(base)
                    digits += [remainder]
            return digits

        def from_nega(arr):
            return sum([arr[i] * ((base) ** i) for i in range(len(arr))])

        return to_nega if dir == Dir.To else from_nega

    return negaverter


if __name__ == "__main__":
    negabinary = make_negabase(-2)
    to_negabinary = negabinary(Dir.To)
    from_negabinary = negabinary(Dir.From)

    print(to_negabinary(10))
    print(from_negabinary([0, 1, 1, 1, 1]))

    for i in range(-10000, 10000):
        assert i == from_negabinary(to_negabinary(i))