def read_file(filename):
    with open(f"{filename}", "r") as infile:
        output = infile.read().splitlines()
    return output

class Location:
    def __init__(self, x, y):
        self.x = x
        self.y = y

    @property
    def location(self):
        return (self.x, self.y)

    def move(self, direction, number=1):
        if direction.upper() == "L":
            self.move_left()
        elif direction.upper() == "R":
            self.move_right()
        elif direction.upper() == "U":
            self.move_up()
        elif direction.upper() == "D":
            self.move_down()
        else:
            raise ValueError

    def move_left(self):
        self.x = self.x - 1

    def move_right(self):
        self.x = self.x + 1

    def move_up(self):
        self.y = self.y + 1

    def move_down(self):
        self.y = self.y - 1


def main(knots_to_track):
    lines = read_file("inputs/9.csv")

    knots = []
    for i in range(knots_to_track):
        knots.append(Location(0,0))

    tail_locations = [knots[-1:][0].location]

    for line in lines:
        direction_to_move = line.split(" ")[0]
        spaces_to_move = int(line.split(" ")[1])
        for i in range(spaces_to_move):
            knots[0].move(direction_to_move)
            for j in range(1,len(knots)):
                delta = Location(knots[j-1].x - knots[j].x, knots[j-1].y - knots[j].y)
                if abs(delta.x) <= 1 and abs(delta.y) <= 1:
                    pass
                else:
                    if delta.location == (2,0):
                        knots[j].move_right()
                    elif delta.location == (-2,0):
                        knots[j].move_left()
                    elif delta.location == (0,2):
                        knots[j].move_up()
                    elif delta.location == (0,-2):
                        knots[j].move_down()
                    elif delta.x > 0 and delta.y > 0:
                        knots[j].move_right()
                        knots[j].move_up()
                    elif delta.x > 0 and delta.y < 0:
                        knots[j].move_right()
                        knots[j].move_down()
                    elif delta.x < 0 and delta.y > 0:
                        knots[j].move_left()
                        knots[j].move_up()
                    elif delta.x < 0 and delta.y < 0:
                        knots[j].move_left()
                        knots[j].move_down()

            tail_locations.append(knots[-1:][0].location)

    print(len(set(tail_locations)))

if __name__ == "__main__":
    main(2)
    main(10)