from math import atan2, sqrt
import os
from typing import Tuple


inputfile = os.path.join(os.path.dirname(__file__), "input/day10_input")


def get_asteroids():
    with open(inputfile) as fp:
        lines = [x.rstrip() for x in fp.readlines()]
        return [(x, y)
                for y, line in enumerate(lines)
                for x, m in enumerate(line)
                if m == '#']


def calc_arc(origin: Tuple[int, int], target: Tuple[int, int]) -> float:
    return atan2(target[0] - origin[0], target[1] - origin[1])


def test_day10a():
    max = 0
    found = (0, 0)
    asts = get_asteroids()
    for my in asts:
        angles = {calc_arc(my, target) for target in asts}
        if len(angles) > max:
            max = len(angles)
            found = my

    print(f'Station is at {found} with {max} visible asteroids')
    assert max == 303


def test_day10b():
    station = (26, 29)
    res = None
    count = 0
    asts = get_asteroids()
    asts.remove(station)
    while not res:
        angles = {calc_arc(station, target): target for target in asts}
        for ang in sorted(angles.keys(), reverse=True):
            asts.remove(angles[ang])
            count += 1
            if count == 200:
                res = angles[ang]
                break
    assert res[0] * 100 + res[1] == 408