import time

import neopixel
from machine import I2C, PWM, Pin, Timer

import ssd1306
from hx711 import *

buzzer = PWM(Pin(8, Pin.OUT))
neo = neopixel.NeoPixel(Pin(16), 1)
button = Pin(7, Pin.IN, Pin.PULL_UP)
i2c = I2C(1, scl=Pin(3), sda=Pin(2), freq=200000)
display = ssd1306.SSD1306_I2C(128, 64, i2c)
hx = hx711(Pin(14), Pin(15))
scaling = 410
value = 0
tara = 0
last_button = None


# freq:hz, duration: ms
def beep(freq, duration):
    buzzer.freq(freq)
    buzzer.duty_u16(22768)
    time.sleep_ms(duration)
    buzzer.duty_u16(0)


def led(r, g, b):
    neo[0] = (r, g, b)
    neo.write()


def callback(pin):
    global last_button, tara
    if not last_button or time.ticks_diff(time.ticks_ms(), last_button) > 500:
        last_button = time.ticks_ms()
    else:
        print("Nope")
        return

    print("Interrupt has occured")
    beep(1000, 100)
    tara = value
    print("Tara is {}".format(tara))


smoothing = 3
smoothing_values = []


def read_scale(_):
    global value, smoothing_values
    val = hx.get_value()
    corrected = val / scaling
    smoothing_values.append(corrected)
    smoothing_values = smoothing_values[-smoothing:]

    value = int(sum(smoothing_values) / smoothing)


def main():
    global tara
    print("Let's go!")
    led(0, 0, 50)

    display.text("Hello, World!", 0, 0, 1)
    display.show()

    # 2. power up
    hx.set_power(hx711.power.pwr_up)

    # 3. [OPTIONAL] set gain and save it to the hx711
    # chip by powering down then back up
    hx.set_gain(hx711.gain.gain_128)
    hx.set_power(hx711.power.pwr_down)
    hx711.wait_power_down()
    hx.set_power(hx711.power.pwr_up)

    # 4. wait for readings to settle
    hx711.wait_settle(hx711.rate.rate_10)

    display.text("Tara....", 0, 20, 1)
    display.show()

    for _ in range(3):
        read_scale(None)

    print("offset: {}".format(value))
    tara = value

    tim = Timer()
    tim.init(period=100, mode=Timer.PERIODIC, callback=read_scale)

    button.irq(trigger=Pin.IRQ_RISING, handler=callback)

    while True:
        x = value - tara
        display.fill(0)
        display.text("{} g".format(x), 0, 20, 1)
        display.show()
        time.sleep_ms(20)


if __name__ == "__main__":
    buzzer.init()
    main()
    hx.close()
    buzzer.deinit()