from collections import Counter
import time
# import operator


def read_moves():
    with open('day24/input') as reader:
        return reader.read().splitlines()


def split_move(move):
    split_moves = []
    cur = ''
    for c in move:
        if cur == '' and c in ('e', 'w'):
            split_moves.append(c)
        elif c in ('n', 's'):
            cur = c
        else:
            split_moves.append(cur + c)
            cur = ''
    return split_moves


move_set = {'e': (2, 0), 'w': (-2, 0), 'ne': (1, 1), 'nw': (-1, 1), 'se': (1, -1), 'sw': (-1, -1)}


def add_move(a, b):
    return a[0]+b[0], a[1]+b[1]
    # return tuple(map(sum, zip(a, b)))
    # return tuple(map(operator.add, a, b))


def reduce_moves(move):
    tile = (0, 0)
    for m in move:
        tile = add_move(tile, move_set[m])
    return tile


moves = read_moves()
split_moves = map(split_move, moves)
reduced_moves = map(reduce_moves, split_moves)

tile_count = Counter(reduced_moves)

black_tiles = [tile for tile, amount in tile_count.items() if amount % 2 == 1]

print(len(black_tiles))


# part2
def black_needs_to_turn_white(adjacents, current_black):
    black_adjacent = adjacents.intersection(current_black)
    return len(black_adjacent) == 0 or len(black_adjacent) > 2


def white_needs_to_turn_black(white, current_black):
    adjacent_to_white = get_adjacents(white)
    blacks_adjacent_to_white = adjacent_to_white.intersection(current_black)
    return len(blacks_adjacent_to_white) == 2


def get_adjacents(current):
    adjacents = set()
    for m in move_set.values():
        adjacents.add(add_move(current, m))
    return adjacents


start = time.time()
previous_black = set(black_tiles)
for i in range(100):
    black_next = set()
    already_checked = set(previous_black)

    for black in previous_black:
        adjacents = get_adjacents(black)
        if not black_needs_to_turn_white(adjacents, previous_black):
            black_next.add(black)

        for a in adjacents:
            if a not in already_checked:
                already_checked.add(a)
                if white_needs_to_turn_black(a, previous_black):
                    black_next.add(a)

    if i == 99:
        print("Day {}: {}".format(str(i+1), len(black_next)))
    previous_black = black_next

end = time.time()
print(end - start)