from __future__ import absolute_import

import numpy as np

from constants import *

from animation.transform import ApplyMethod
from animation.composition import LaggedStart
from mobject.svg.drawings import Car
from mobject.types.vectorized_mobject import VGroup
from mobject.geometry import Circle
from utils.config_ops import digest_config

class MoveCar(ApplyMethod):
    CONFIG = {
        "moving_forward" : True,
    }
    def __init__(self, car, target_point, **kwargs):
        assert isinstance(car, Car)
        ApplyMethod.__init__(self, car.move_to, target_point, **kwargs)
        displacement = self.target_mobject.get_right()-self.starting_mobject.get_right()
        distance = np.linalg.norm(displacement)
        if not self.moving_forward:
            distance *= -1
        tire_radius = car.get_tires()[0].get_width()/2
        self.total_tire_radians = -distance/tire_radius

    def update_mobject(self, alpha):
        ApplyMethod.update_mobject(self, alpha)
        if alpha == 0:
            return
        radians = alpha*self.total_tire_radians
        for tire in self.mobject.get_tires():
            tire.rotate_in_place(radians)

class Broadcast(LaggedStart):
    CONFIG = {
        "small_radius" : 0.0,
        "big_radius" : 5,
        "n_circles" : 5,
        "start_stroke_width" : 8,
        "color" : WHITE,
        "remover" : True,
        "lag_ratio" : 0.7,
        "run_time" : 3,
        "remover" : True,
    }
    def __init__(self, focal_point, **kwargs):
        digest_config(self, kwargs)
        circles = VGroup()
        for x in range(self.n_circles):
            circle = Circle(
                radius = self.big_radius, 
                stroke_color = BLACK,
                stroke_width = 0,
            )
            circle.move_to(focal_point)
            circle.save_state()
            circle.scale_to_fit_width(self.small_radius*2)
            circle.set_stroke(self.color, self.start_stroke_width)
            circles.add(circle)
        LaggedStart.__init__(
            self, ApplyMethod, circles,
            lambda c : (c.restore,),
            **kwargs
        )