#AFRINA RIDWANA BINTI AHMAD RIZAL
import machine
import uasyncio as asyncio
from lcd1602 import LCD
from hcsr04 import HCSR04

i2c = machine.I2C(1, scl=machine.Pin(7), sda=machine.Pin(6))
lcd = LCD(addr=0x27)
pot = machine.ADC(28)
ledR = machine.Pin(12, machine.Pin.OUT)
ledG = machine.Pin(13, machine.Pin.OUT)
PB = machine.Pin(16, machine.Pin.IN, machine.Pin.PULL_UP)
sensor = HCSR04(trigger_pin=2, echo_pin=3)

async def display_startup():
    lcd.clear()
    lcd.write(0, 0, "Distance Counter")

async def led_blink():
    await asyncio.sleep(2)
    while True:
        ledG.value(1)
        await asyncio.sleep(0.05)
        ledG.value(0)
        await asyncio.sleep(0.05)

async def standby_mode():
    last_pot_value = None
    while True:
        anVal = pot.read_u16() / 65535.0
        pot_value = int(10 + anVal * 100)
        if pot_value != last_pot_value:
            lcd.clear()
            lcd.write(0, 0, "User Input")
            lcd.write(0, 1, "Dist: {} cm".format(pot_value))
            last_pot_value = pot_value
        await asyncio.sleep(0.5)
        if PB.value() == 0:
            await asyncio.sleep(0.2)
            while PB.value() == 0:
                await asyncio.sleep(0.1)
            return pot_value

async def scan_mode(threshold):
    last_distance = None
    while True:
        distance = sensor.distance_cm()
        if distance != last_distance:
            ledR.value(1 if distance < threshold else 0)
            lcd.clear()
            lcd.write(0, 0, "Distance: {} cm".format(distance))
            lcd.write(0, 1, "Object: Yes" if distance < threshold else "Object: No")
            last_distance = distance
        await asyncio.sleep(0.1)
        if PB.value() == 0:
            await asyncio.sleep(0.2)
            while PB.value() == 0:
                await asyncio.sleep(0.1)
            ledR.off()
            return

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

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