("Project: Food Storage Monitoring System")
("This program will monitor temperature and humidity of the food in the storage")
("Trigger alerts on an OLED screen and with a buzzer if values go beyond thresholds.")
("Develop by: Ikhwan Munib")
("Date: 15/4/2026")

# Import library / module
from machine import Pin, PWM, SoftI2C, ADC
import oled_library
import dht
from time import sleep

# Pin Declaration   
dht_sensor = dht.DHT22(Pin(4))
red_led = Pin(14, Pin.OUT)
green_led = Pin(27, Pin.OUT)
buzzer = PWM(Pin(18, Pin.OUT))
buzzer.freq(1000)
SCL1_Pin = Pin(23)
SDA1_Pin = Pin(22)
OLED1_Pin = SoftI2C(scl=SCL1_Pin, sda=SDA1_Pin)


# Treshold 
TEMP_LIMIT = 30 #'C
HUM_LIMIT = 70 # %
GAS_LIMIT = 2000 #ADC value
LIGHT_LIMIT = 2000 #ADC value

#Push Button
button = Pin(25, Pin.IN, Pin.PULL_UP)

# Potentiometers 
gas_sensor = ADC(Pin(34))
ldr_sensor = ADC(Pin(35))
gas_sensor.atten(ADC.ATTN_11DB)
ldr_sensor.atten(ADC.ATTN_11DB)

# Object Declaration
screen1 = oled_library.SSD1306_I2C(width=128, height=64, i2c=OLED1_Pin)


# Main Program Loop
while True:
    try:
    dht_sensor.measure()
    temp = dht_sensor.temperature()
    hum = dht_sensor.humidity()
    except:
    temp = 0
    hum = 0

 # Read simulated sensors
    gas = gas_sensor.read()
    light = ldr_sensor.read()

    # Adjustable threshold (optional scaling)
    adjust = threshold_pot.read()
    GAS_LIMIT = 1000 + (adjust / 4095 * 2000)

    # --------------------------
    # CHECK CONDITIONS
    # --------------------------

    unsafe = False

    if temp > TEMP_LIMIT or hum > HUM_LIMIT:
        unsafe = True

    if gas > GAS_LIMIT:
        unsafe = True

    if light > LIGHT_LIMIT:
        unsafe = True

    # --------------------------
    # BUTTON (ACKNOWLEDGE)
    # --------------------------
    if button.value() == 0:
        alert_ack = True
        buzzer.duty(0)

    # --------------------------
    # OUTPUT CONTROL
    # --------------------------

    if unsafe and not alert_ack:
        # UNSAFE
        red_led.on()
        green_led.off()
        buzzer.duty(512)

        status = "UNSAFE!"

    else:
        # SAFE
        red_led.off()
        green_led.on()
        buzzer.duty(0)

        status = "SAFE"
        alert_ack = False

    # --------------------------
    # OLED DISPLAY
    # --------------------------

    oled.fill(0)

    oled.text("Temp: {:.1f}C".format(temp), 0, 0)
    oled.text("Hum : {:.1f}%".format(hum), 0, 10)
    oled.text("Gas : {}".format(gas), 0, 20)
    oled.text("Light: {}".format(light), 0, 30)

    oled.text(status, 0, 50)

    oled.show()

    # --------------------------
    # SERIAL MONITOR
    # --------------------------

    print("Temp:", temp, "Hum:", hum,
          "Gas:", gas, "Light:", light,
          "Status:", status)

    sleep(1)