# ADRIANA SARAH BINTI AHMAD FAIZA (52224123439) // PRACTICAL TEST

from machine import Pin, ADC, PWM, SoftI2C
import time
import dht
from i2c_lcd import I2cLcd

# Pin Definitions
DHT_PIN = 4  # DHT22 sensor pin
GAS_PIN = ADC(Pin(34))  # Wokwi Gas Sensor
GAS_PIN.atten(ADC.ATTN_11DB)  # Set ADC to 0-3.3V range
TRIG_PIN = Pin(14, Pin.OUT)  # Ultrasonic Trigger pin
ECHO_PIN = Pin(27, Pin.IN)  # Ultrasonic Echo pin
LED_PIN = 2  # LED pin
SERVO_PIN = PWM(Pin(25), freq=50)  # Servo Motor pin
I2C_SCL = Pin(22)  # I2C Clock pin
I2C_SDA = Pin(21)  # I2C Data pin

# I2C and LCD Initialization
i2c = SoftI2C(scl=I2C_SCL, sda=I2C_SDA)
lcd = I2cLcd(i2c, 0x27, 2, 16)  # LCD (2 rows, 16 columns)

# DHT22 Initialization
dht_sensor = dht.DHT22(Pin(DHT_PIN))

# LED Setup
led = Pin(LED_PIN, Pin.OUT)

# Servo Motor Setup
servo = SERVO_PIN

# Blink LED for emergencies
def blink_led():
    led.on()
    time.sleep(0.5)
    led.off()
    time.sleep(0.5)

# Scale gas readings from ADC to ppm
def scale_gas_level_to_ppm(adc_value):
    """Scale the raw ADC value to a range of 0.1 ppm to 400 ppm."""
    max_adc = 4095  # Max ADC value for 11dB attenuation
    gas_ppm = 0.1 + (adc_value / max_adc) * (400 - 0.1)
    return gas_ppm

# Measure distance using Ultrasonic Sensor
def get_distance():
    TRIG_PIN.value(1)
    time.sleep_us(10)
    TRIG_PIN.value(0)
    
    while ECHO_PIN.value() == 0:
        pass
    start = time.ticks_us()
    while ECHO_PIN.value() == 1:
        pass
    end = time.ticks_us()
    
    duration = time.ticks_diff(end, start)
    return (duration / 2) / 29.1  # Speed of sound = 343 m/s

# Read sensors
def read_sensors():
    try:
        # DHT22 sensor
        dht_sensor.measure()
        temperature = dht_sensor.temperature()
        humidity = dht_sensor.humidity()
        
        # Gas sensor
        gas_value = GAS_PIN.read()
        gas_ppm = scale_gas_level_to_ppm(gas_value)  # Scale gas value to ppm
        
        # Ultrasonic sensor
        distance = get_distance()
        
        return temperature, humidity, gas_ppm, distance
    except Exception as e:
        print(f"Error reading sensors: {e}")
        return None, None, None, None

# Display data on LCD
def display_on_lcd(temp, humidity, gas, distance):
    lcd.clear()
    lcd.putstr(f"Temp: {temp:.1f}C\nHum: {humidity:.1f}%")
    time.sleep(2)
    lcd.clear()
    lcd.putstr(f"Gas: {gas:.1f}ppm\nDist: {distance:.1f}cm")

# Emergency Actions
def emergency_actions(temp, distance):  # Removed gas sensor influence
    if temp > 35 or distance < 20:  # Gate logic only depends on temp and distance
        print("Emergency condition detected!")
        blink_led()
        servo.duty(40)  # Open vent (e.g., 90 degrees)
    else:
        print("Conditions normal. Closing gate...")
        led.off()
        servo.duty(0)  # Close vent (e.g., 0 degrees)

# Main Loop
def main():
    print("Starting Smart Agriculture System...")
    time.sleep(2)
    
    while True:
        temp, humidity, gas, distance = read_sensors()
        if temp is None or humidity is None or gas is None or distance is None:
            print("Skipping cycle due to sensor error.")
            continue
        
        # Display data on LCD
        display_on_lcd(temp, humidity, gas, distance)
        
        # Check emergency conditions and act (gas sensor excluded)
        emergency_actions(temp, distance)
        
        time.sleep(2)

if __name__ == "__main__":
    main()