import utils

def add_neighbors(the_map, neighbors, closed, near_y, near_x):
    points = utils.compass(near_x, near_y)

    for x,y in points:
        if the_map.inbounds(x,y) and closed[y, x] == utils.SPACE:
            closed[y, x] = utils.WALL
            neighbors.append([x,y])

def calculate_paths(the_map, paths, in_grid):
    height, width = paths.shape
    paths.fill(utils.PATH_LIMIT)
    closed = the_map.map.copy()
    starting_pixels = []
    open_pixels = []

    counter = 0
    while counter < height * width:
        x = counter % width
        y = counter // width
        if in_grid[y, x] == 0:
            paths[y, x] = 0
            closed[y, x] = utils.WALL
            starting_pixels.append([x,y])
        counter += 1

    for x, y in starting_pixels:
        add_neighbors(the_map, open_pixels, closed, y, x)

    counter = 1
    while counter < utils.PATH_LIMIT and open_pixels:
        next_open = []
        for x,y in open_pixels:
            paths[y, x] = counter
            add_neighbors(the_map, next_open, closed, y, x)
        open_pixels = next_open
        counter += 1

    for x, y in open_pixels:
        paths[y, x] = counter