from machine import ADC, Pin      # Import ADC for reading analog sensor and Pin for GPIO control
import time                       # Import time for delays
from gpio_lcd import GpioLcd      # Import library to control 16x2 LCD

# Initialize the LCD with appropriate GPIO pins connected to RS, Enable, D4–D7
lcd = GpioLcd(rs_pin=Pin(16),
              enable_pin=Pin(17),
              d4_pin=Pin(18),
              d5_pin=Pin(19),
              d6_pin=Pin(20),
              d7_pin=Pin(21),
              num_lines=2,
              num_columns=16)

# Initialize soil moisture sensor using analog pin GP28 (ADC2)
sensor = ADC(28)

# Initialize pump (represented by an LED) connected to digital pin GP15
pump = Pin(15, Pin.OUT)

# Set a threshold value to decide when soil is considered "dry"
# You may need to adjust this value after checking actual sensor readings
threshold = 30000

# Infinite loop to continuously read sensor values and control the pump
while True:
    # Read the analog value from the soil moisture sensor (0–65535)
    value = sensor.read_u16()
    print("Value:", value)  # Print the sensor reading to the serial monitor

    # Clear the LCD before updating to avoid leftover characters
    lcd.clear()

    # Display the raw moisture value on the first row of the LCD
    lcd.move_to(0, 0)
    lcd.putstr(f"Moisture: {value:5d}")

    # Check if soil is dry based on threshold value
    if value < threshold:
        pump.value(1)  # Turn ON pump (or LED)
        print("Soil dry - Pump ON")  # Print status in console
        lcd.move_to(0, 1)
        lcd.putstr("Status: Pump ON ")  # Display pump status on second row
    else:
        pump.value(0)  # Turn OFF pump (or LED)
        print("Soil wet - Pump OFF")  # Print status in console
        lcd.move_to(0, 1)
        lcd.putstr("Status: Pump OFF")  # Display pump status on second row

    # Wait for 2 seconds before the next reading
    time.sleep(2)