"""Solution for 2020/24"""

from collections import defaultdict

instructions = []
with open('input', 'r') as f:
    for line in f.readlines():
        line = line.strip()
        i = 0
        instruction = []
        while i < len(line):
            if line[i] in ['w', 'e']:
                instruction.append(line[i])
            else:
                instruction.append(line[i:i+2])
                i += 1
            i += 1
        instructions.append(instruction)


print(instructions)

MOVEMENTS = {
    'e': (1, 0),
    'w': (-1, 0),
    'ne': (0, 1),
    'sw': (0, -1),
    'nw': (-1, 1),
    'se': (1, -1),
}

MOVES = 100


def main():
    flipped_tiles = defaultdict(int)

    for instruction in instructions:
        coord = parse_instruction(instruction)
        flipped_tiles[coord] += 1

        print(''.join(instruction), coord)
    blacks = set([x[0] for x in flipped_tiles.items() if x[1] % 2 == 1])

    for day in range(MOVES):
        new_blacks = set()
        bbox = get_bbox(blacks)
        for x in range(bbox[0] - 1, bbox[2] + 2):
            for y in range(bbox[1] - 1, bbox[3] + 2):
                coord = (x, y)
                neighbors = get_neighbors(coord)
                adj_blacks = len([x for x in neighbors if x in blacks])
                is_black = coord in blacks
                if is_black and adj_blacks in [1, 2]:
                    new_blacks.add(coord)
                elif not is_black and adj_blacks == 2:
                    new_blacks.add(coord)
        blacks = new_blacks
        print(f'Day {day+1:>3}: {len(blacks)}')


def parse_instruction(instruction):
    coord = (0, 0)
    for move in instruction:
        dx, dy = MOVEMENTS[move]
        coord = (coord[0] + dx, coord[1] + dy)
    return coord


def get_bbox(coords):
    x_coords = list(map(lambda coord: coord[0], coords))
    y_coords = list(map(lambda coord: coord[1], coords))
    return min(x_coords), min(y_coords), max(x_coords), max(y_coords)


def get_neighbors(coord):
    neigh = []
    for dx, dy in MOVEMENTS.values():
        neigh.append((coord[0] + dx, coord[1] + dy))
    return neigh


main()