import aoclib
import itertools

DAY = 9
TEST_SOLUTION_PART1 = 127
TEST_SOLUTION_PART2 = 62


class NumberCruncher:
    def __init__(self, preamble):
        self.buffer = []
        self.preamble = preamble

    def addNumber(self, number):
        self.buffer.append(number)
        if len(self.buffer) > self.preamble:
            self.buffer = self.buffer[1:]

    def isValidNextNumber(self, number):
        if len(self.buffer) < self.preamble:
            return True

        for combination in itertools.combinations(self.buffer, 2):
            if sum(combination) == number:
                return True

        return False


def part1(test_mode=False):
    my_input = aoclib.getInputAsArray(day=DAY, return_type=int, test=test_mode)
    if test_mode:
        cruncher = NumberCruncher(5)
    else:
        cruncher = NumberCruncher(25)

    for i in my_input:
        if not cruncher.isValidNextNumber(i):
            return i

        cruncher.addNumber(i)

    return 0


def part2(test_mode=False):
    my_input = aoclib.getInputAsArray(day=DAY, return_type=int, test=test_mode)
    sum_to_find = part1(test_mode)

    for start_index in range(0, len(my_input)):
        for stop_index in range(start_index + 1, len(my_input) - start_index - 1):
            if sum(my_input[start_index:stop_index]) == sum_to_find:
                return min(my_input[start_index:stop_index]) + max(my_input[start_index:stop_index])

    return 0