from itertools import product, chain, starmap

SURFACE = 0b01
SIDE = 0b10
def square(x, y, radius, min_x, min_y, max_x, max_y, mode):
    """
    Coordinates in/on the square center: (x, y), side length: 2 * radius

    :param x: The center abscissa
    :param y: The center ordinate
    :param radius: The square "radius"
    :param min_x: The minimum abscissa value (included)
    :param min_y: The minimum ordinate value (included)
    :param max_x: The maximum abscissa value (exluded)
    :param max_y: The maximum ordinate value (exluded)
    :param mode: SURFACE, SIDE or both

    The function creates a square whose center is at (:x:, :y:) with
    a side length equals to two times the :radius:. It also creates
    a second square out of the Point(:min_x:, :min_y:) and the
    Point(:max_x: - 1, :max_y: - 1). Only points that are part of both
    squares are returned.

    In SIDE mode, it matches points on the side of the square, points
    whose distance to the center is exactly equals to :radius:.

    In SURFACE mode, it matches points in the surface of the square,
    points whose distance to the center is stricly less than :radius:.

    Example:

    000000  Center #, radius 3, min_x 0, min_y 0, max_x 5, max_y 4
    01111-  0: outside the square
    01222-  1: matched in SIDE mode
    01222-  2: matched in SURFACE mode
    0--#--  -: excluded by the boundaries
    """
    inbound = lambda point: min_x <= point[0] < max_x \
                            and min_y <= point[1] < max_y
    translate = lambda vector: (x + vector[0], y + vector[1])
    notcenter = lambda vector: vector[0] != 0 or vector[1] != 0
    vectors = []

    if mode & SURFACE:
        vectors.append((range(-radius + 1, radius), range(-radius + 1, radius)))

    if mode & SIDE:
        vectors.append(((-radius, radius), range(-radius, radius + 1)))
        vectors.append((range(-radius + 1, radius), (-radius, radius)))

    yield from filter(inbound,
               map(translate,
               chain.from_iterable(
               starmap(product,
               vectors))))