#!/bin/python3

from collections import defaultdict
from queue import Queue

cubes = set()

with open('inputs/day18.txt', 'r') as f:
    for line in f:
        [x, y, z] = line.split(',')
        cubes.add((int(x), int(y), int(z)))

def ordered(pos1, pos2):
    if pos1 > pos2:
        return (pos1, pos2)
    else:
        return (pos2, pos1)

sides = defaultdict(lambda: 0)
for cube in cubes:
    (x, y, z) = cube
    cube_sides = []
    cube_sides.append(ordered(cube, (x+1, y, z)))
    cube_sides.append(ordered(cube, (x-1, y, z)))
    cube_sides.append(ordered(cube, (x, y+1, z)))
    cube_sides.append(ordered(cube, (x, y-1, z)))
    cube_sides.append(ordered(cube, (x, y, z+1)))
    cube_sides.append(ordered(cube, (x, y, z-1)))

    for side in cube_sides:
        sides[side] += 1

outer_sides = set()
for side, count in sides.items():
    if count == 1:
        outer_sides.add(side)

print("part1", len(outer_sides))

# Determine max and min coords
x_min = min(map(lambda a: a[0], cubes))
x_max = max(map(lambda a: a[0], cubes))
y_min = min(map(lambda a: a[1], cubes))
y_max = max(map(lambda a: a[1], cubes))
z_min = min(map(lambda a: a[2], cubes))
z_max = max(map(lambda a: a[2], cubes))

# Increase bounds by 1 in all directions
x_min -= 1
x_max += 1
y_min -= 1
y_max += 1
z_min -= 1
z_max += 1

# Flood fill from 1 corner to find all reachable cubes.
class SetQueue(Queue):
    def _init(self, maxsize):
        self.queue = set()
    def _put(self, item):
        self.queue.add(item)
    def _get(self):
        return self.queue.pop()

cube_queue = SetQueue()
cube_queue.put((x_min, y_min, z_min))
reachable_cubes = set()

max_cubes = (x_max - x_min) * (y_max - y_min) * (z_max - z_min)
while True:
    if cube_queue.empty():
        break
    cube = cube_queue.get()
    (x, y, z) = cube
    reachable_cubes.add(cube)

    neighbors = []
    neighbors.append((x+1, y, z))
    neighbors.append((x-1, y, z))
    neighbors.append((x, y+1, z))
    neighbors.append((x, y-1, z))
    neighbors.append((x, y, z+1))
    neighbors.append((x, y, z-1))

    for neighbor in neighbors:
        (nx, ny, nz) = neighbor
        if nx < x_min or nx > x_max or ny < y_min or ny > y_max or nz < z_min or nz > z_max:
            continue
        if neighbor in reachable_cubes or neighbor in cubes:
            continue

        # Found a new empty cube!
        cube_queue.put(neighbor)

# Okay, found all empty cube outside the droplet.

surface_sides = set()

for empty in reachable_cubes:
    (x, y, z) = empty
    cube_sides = []
    cube_sides.append(ordered(empty, (x+1, y, z)))
    cube_sides.append(ordered(empty, (x-1, y, z)))
    cube_sides.append(ordered(empty, (x, y+1, z)))
    cube_sides.append(ordered(empty, (x, y-1, z)))
    cube_sides.append(ordered(empty, (x, y, z+1)))
    cube_sides.append(ordered(empty, (x, y, z-1)))

    for side in cube_sides:
        if side in outer_sides:
            surface_sides.add(side)

print("part2", len(surface_sides))