import carla
import pygame

import queue
import numpy as np

def carla_vec_to_np_array(vec):
    return np.array([vec.x,
                     vec.y,
                     vec.z])

class CarlaSyncMode(object):
    """
    Context manager to synchronize output from different sensors. Synchronous
    mode is enabled as long as we are inside this context

        with CarlaSyncMode(world, sensors) as sync_mode:
            while True:
                data = sync_mode.tick(timeout=1.0)

    """

    def __init__(self, world, *sensors, **kwargs):
        self.world = world
        self.sensors = sensors
        self.frame = None
        self.delta_seconds = 1.0 / kwargs.get('fps', 20)
        self._queues = []
        self._settings = None

    def __enter__(self):
        self._settings = self.world.get_settings()
        self.frame = self.world.apply_settings(carla.WorldSettings(
            no_rendering_mode=False,
            synchronous_mode=True,
            fixed_delta_seconds=self.delta_seconds))

        def make_queue(register_event):
            q = queue.Queue()
            register_event(q.put)
            self._queues.append(q)

        make_queue(self.world.on_tick)
        for sensor in self.sensors:
            make_queue(sensor.listen)
        return self

    def tick(self, timeout):
        self.frame = self.world.tick()
        data = [self._retrieve_data(q, timeout) for q in self._queues]
        assert all(x.frame == self.frame for x in data)
        return data

    def __exit__(self, *args, **kwargs):
        self.world.apply_settings(self._settings)

    def _retrieve_data(self, sensor_queue, timeout):
        while True:
            data = sensor_queue.get(timeout=timeout)
            if data.frame == self.frame:
                return data



def carla_img_to_array(image):
    array = np.frombuffer(image.raw_data, dtype=np.dtype("uint8"))
    array = np.reshape(array, (image.height, image.width, 4))
    array = array[:, :, :3]
    array = array[:, :, ::-1]
    return array


def draw_image(surface, image, blend=False):
    array = np.frombuffer(image.raw_data, dtype=np.dtype("uint8"))
    array = np.reshape(array, (image.height, image.width, 4))
    array = array[:, :, :3]
    array = array[:, :, ::-1]
    image_surface = pygame.surfarray.make_surface(array.swapaxes(0, 1))
    if blend:
        image_surface.set_alpha(100)
    surface.blit(image_surface, (0, 0))

def draw_image_np(surface, image, blend=False):
    array = image
    image_surface = pygame.surfarray.make_surface(array.swapaxes(0, 1))
    if blend:
        image_surface.set_alpha(100)
    surface.blit(image_surface, (0, 0))


def should_quit():
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            return True
        elif event.type == pygame.KEYUP:
            if event.key == pygame.K_ESCAPE:
                return True
    return False

def find_weather_presets():
    import re
    rgx = re.compile('.+?(?:(?<=[a-z])(?=[A-Z])|(?<=[A-Z])(?=[A-Z][a-z])|$)')
    name = lambda x: ' '.join(m.group(0) for m in rgx.finditer(x))
    presets = [x for x in dir(carla.WeatherParameters) if re.match('[A-Z].+', x)]
    return [(getattr(carla.WeatherParameters, x), name(x)) for x in presets]