# SPDX-License-Identifier: MIT
#
# Little christmas candle
#
# Author:    Nils Freydank <nils.freydank@datenschutz-ist-voll-doof.de>
# Year:      2022
# Copyright: MIT

import machine
import time

pin_led1 = machine.Pin(22)
pin_led2 = machine.Pin(10)
pin_led3 = machine.Pin(8)


def _get_new_duty(
    factor: int, signed_step_width: int, limit_lower: int, limit_upper: int
) -> Tuple[int, int]:
    duty_fac: int = factor

    duty_fac += signed_step_width
    if duty_fac > limit_upper:
        duty_fac = limit_upper
        signed_step_width = (-1) * signed_step_width
    elif duty_fac < limit_lower:
        duty_fac = limit_lower
        signed_step_width = (-1) * signed_step_width

    return duty_fac, signed_step_width


def flicker() -> None:
    pwm_led1 = machine.PWM(pin_led1)
    pwm_led2 = machine.PWM(pin_led2)
    pwm_led3 = machine.PWM(pin_led3)

    pwm_led1.freq(1_000)
    pwm_led2.freq(1_000)
    pwm_led3.freq(1_000)

    duty_fac_led1: int = 0
    signed_step_width_led1: int = 1
    duty_fac_led2: int = 0
    signed_step_width_led2: int = 1
    duty_fac_led3: int = 0
    signed_step_width_led3: int = 1

    delay_s: float = 0.01

    while True:
        duty_fac_led1, signed_step_width_led1 = _get_new_duty(
            duty_fac_led1, signed_step_width_led1, 240, 250
        )
        pwm_led1.duty_u16(duty_fac_led1**2)

        duty_fac_led2, signed_step_width_led2 = _get_new_duty(
            duty_fac_led2, signed_step_width_led2, 0, 200
        )
        pwm_led2.duty_u16(duty_fac_led2**2)

        duty_fac_led3, signed_step_width_led3 = _get_new_duty(
            duty_fac_led3, signed_step_width_led3, 30, 100
        )
        pwm_led2.duty_u16(duty_fac_led3**2)

        time.sleep(delay_s)


# vim:fileencoding=utf-8:ts=4:syntax=python:expandtab