from machine import Pin, I2C
from time import sleep
import time
from lcd_api import LcdApi
from i2c_lcd import I2cLcd

# Pin Configuration
PIR_PIN = 14            # GPIO pin for PIR motion sensor
TRIG_PIN = 12           # GPIO pin for ultrasonic sensor trigger
ECHO_PIN = 13           # GPIO pin for ultrasonic sensor echo
LED_PIN = 2             # GPIO pin for LED

# I2C Configuration for LCD
I2C_ADDR = 0x27         # I2C address for LCD
I2C_SDA = 21            # GPIO pin for I2C SDA
I2C_SCL = 22            # GPIO pin for I2C SCL

# Distance Threshold (in cm)
DISTANCE_THRESHOLD = 100

# Setup GPIO Pins
pir = Pin(PIR_PIN, Pin.IN)
led = Pin(LED_PIN, Pin.OUT)
trig = Pin(TRIG_PIN, Pin.OUT)
echo = Pin(ECHO_PIN, Pin.IN)

# Setup I2C and LCD
i2c = I2C(1, scl=Pin(I2C_SCL), sda=Pin(I2C_SDA), freq=400000)
lcd = I2cLcd(i2c, I2C_ADDR, 4, 20)  # 4x20 LCD

# Function to measure distance using ultrasonic sensor
def measure_distance():
    # Trigger a pulse
    trig.value(0)
    time.sleep_us(2)
    trig.value(1)
    time.sleep_us(10)
    trig.value(0)

    # Measure echo pulse duration
    while echo.value() == 0:
        start = time.ticks_us()
    while echo.value() == 1:
        end = time.ticks_us()

    # Calculate distance
    duration = time.ticks_diff(end, start)
    distance = (duration * 0.0343) / 2  # Speed of sound: 343 m/s
    return distance

# Main loop
try:
    lcd.putstr("Smart Lighting\nInitializing...")
    time.sleep(2)
    lcd.clear()
    lcd.putstr("Waiting for motion...")

    while True:
        motion_detected = pir.value()  # Read PIR sensor
        distance = measure_distance()  # Measure distance

        lcd.clear()
        lcd.putstr(f"Motion: {'Yes' if motion_detected else 'No'}\n")
        lcd.putstr(f"Distance: {distance:.1f} cm\n")

        if motion_detected and distance <= DISTANCE_THRESHOLD:
            # Turn on the light
            led.value(1)
            lcd.putstr("Light: ON ")
        else:
            # Turn off the light
            led.value(0)
            lcd.putstr("Light: OFF")

        time.sleep(0.5)

except KeyboardInterrupt:
    print("Program stopped")
    lcd.clear()