import utime


class CometDual:
    def __init__(self, driver):
        self.driver = driver

    def run(self, preset):
        colors = preset.c if preset.c else [(255, 255, 255)]
        tail = max(1, int(preset.n1) if int(preset.n1) > 0 else 6)
        speed = max(1, int(preset.n2) if int(preset.n2) > 0 else 1)
        gap = max(0, int(preset.n3))
        p1 = 0
        p2 = self.driver.num_leds - 1 - gap
        last = utime.ticks_ms()
        while True:
            d = max(1, int(preset.d))
            now = utime.ticks_ms()
            if utime.ticks_diff(now, last) >= d:
                bg_color = self.driver.apply_brightness(preset.background_or(colors), preset.b)
                for i in range(self.driver.num_leds):
                    self.driver.n[i] = bg_color
                c1 = self.driver.apply_brightness(colors[0 % len(colors)], preset.b)
                c2 = self.driver.apply_brightness(colors[1 % len(colors)] if len(colors) > 1 else colors[0], preset.b)
                for t in range(tail):
                    i1 = p1 - t
                    if 0 <= i1 < self.driver.num_leds:
                        s = (255 * (tail - t)) // max(1, tail)
                        self.driver.n[i1] = ((c1[0]*s)//255, (c1[1]*s)//255, (c1[2]*s)//255)
                    i2 = p2 + t
                    if 0 <= i2 < self.driver.num_leds:
                        s = (255 * (tail - t)) // max(1, tail)
                        self.driver.n[i2] = ((c2[0]*s)//255, (c2[1]*s)//255, (c2[2]*s)//255)
                self.driver.n.write()
                p1 += speed
                p2 -= speed
                if p1 - tail > self.driver.num_leds and p2 + tail < 0:
                    p1 = 0
                    p2 = self.driver.num_leds - 1 - gap
                last = utime.ticks_add(last, d)
                if not preset.a:
                    yield
                    return
            yield