import Adafruit_DHT
import RPi.GPIO as GPIO
import time
import spidev  # For SPI communication with the ADC

# Constants
DHT_SENSOR = Adafruit_DHT.DHT22
DHT_PIN = 22  # GPIO pin for DHT22 data
PIR_PIN = 8  # GPIO pin for PIR sensor
BUZZER_PIN = 20  # GPIO pin for buzzer
LED_PIN = 12  # GPIO pin for LED
PHOTO_CHANNEL = 26  # ADC channel for photoresistor
TEMP_THRESHOLD = 30.0  # Temperature threshold in Celsius
LIGHT_THRESHOLD = 800  # Light level threshold for detecting presence of light

# Setup
GPIO.setmode(GPIO.BCM)
GPIO.setup(PIR_PIN, GPIO.IN)
GPIO.setup(BUZZER_PIN, GPIO.OUT)
GPIO.setup(LED_PIN, GPIO.OUT)

# SPI setup for MCP3008 ADC
spi = spidev.SpiDev()
spi.open(0, 0)  # Open SPI bus 0, device 0
spi.max_speed_hz = 1350000

def read_adc(channel):
    """Read data from MCP3008 ADC"""
    adc = spi.xfer2([1, (8 + channel) << 4, 0])
    data = ((adc[1] & 3) << 8) + adc[2]
    return data

def read_temperature_and_humidity():
    """Read temperature and humidity from DHT22 sensor"""
    humidity, temperature = Adafruit_DHT.read_retry(DHT_SENSOR, DHT_PIN)
    return humidity, temperature

def read_photoresistor():
    """Read light level from photoresistor"""
    value = read_adc(PHOTO_CHANNEL)
    return value

def detect_motion():
    """Detect motion using PIR sensor"""
    return GPIO.input(PIR_PIN)

def sound_buzzer(duration=0.5):
    """Sound the buzzer for a specified duration"""
    GPIO.output(BUZZER_PIN, GPIO.HIGH)
    time.sleep(duration)
    GPIO.output(BUZZER_PIN, GPIO.LOW)

def turn_on_led():
    """Turn on the LED"""
    GPIO.output(LED_PIN, GPIO.HIGH)

def turn_off_led():
    """Turn off the LED"""
    GPIO.output(LED_PIN, GPIO.LOW)

try:
    while True:
        # Read temperature and humidity
        humidity, temperature = read_temperature_and_humidity()
        if humidity is not None and temperature is not None:
            print(f"Temperature: {temperature:.1f}C, Humidity: {humidity:.1f}%")
        else:
            print("Failed to retrieve data from humidity sensor")

        # Read light level
        light_level = read_photoresistor()
        print(f"Light Level: {light_level}")

        # Detect motion
        motion_detected = detect_motion()
        if motion_detected:
            print("Motion detected!")

        # Check extreme conditions
        extreme_condition = False
        if temperature is not None and temperature > TEMP_THRESHOLD:
            print("Temperature exceeds threshold!")
            extreme_condition = True

        if motion_detected and light_level > LIGHT_THRESHOLD:
            print("Motion and light detected!")
            extreme_condition = True

        # Trigger actions on extreme conditions
        if extreme_condition:
            turn_on_led()
            sound_buzzer(1)  # Sound the buzzer for 1 second
        else:
            turn_off_led()

        # Wait before next reading
        time.sleep(2)

except KeyboardInterrupt:
    print("Exiting program")

finally:
    GPIO.cleanup()
    spi.close()