from machine import Pin, ADC
from lcd1602 import LCD
from hcsr04 import HCSR04
import uasyncio as asyncio

lcd = LCD()
led_red = Pin(12, Pin.OUT)
led_green = Pin(13, Pin.OUT)
pushbutton = Pin(16, Pin.IN, Pin.PULL_UP)
pot = ADC(Pin(4))
sensor = HCSR04(trigger_pin=Pin(3), echo_pin=Pin(2))

threshold = 50  # Initialize threshold

async def display():
    lcd.clear()
    lcd.write(0, 0, "Distance Counter")
    await asyncio.sleep(2)

async def blink_green_led():
    while True:
        led_green.value(1)
        await asyncio.sleep(0.1)
        led_green.value(0)
        await asyncio.sleep(0.1)

async def standby_mode():
    while True:
        anVal = pot.read_u16() / 65535  
        pot_value = int(10 + anVal * 90)  
        lcd.clear()
        lcd.write(0, 0, "User Input")
        lcd.write(0, 1, "Dist: {} cm".format(pot_value))
        await asyncio.sleep(0.5) 
        if pushbutton.value() == 0:  
            return pot_value

async def scan_mode(threshold):
    while True:
        distance = sensor.distance_cm()
        if distance < threshold:
            led_red.on()
            lcd.clear()
            lcd.write(0, 0, "Distance: {} cm".format(distance))
            lcd.write(0, 1, "Object: Yes")
        else:
            led_red.off()
            lcd.clear()
            lcd.write(0, 0, "Distance: {} cm".format(distance))
            lcd.write(0, 1, "Object: No")
        await asyncio.sleep(0.1)  
        if pushbutton.value() == 0: 
            led_red.off()
            return


async def main():
    await display()
    
    while True:
        threshold = await standby_mode()
        await scan_mode(threshold)

loop = asyncio.get_event_loop()
loop.create_task(blink_green_led())
loop.create_task(main())
loop.run_forever()