#include <Wire.h>
#include <LiquidCrystal_I2C.h>

// Set the LCD I2C address (usually 0x27 or 0x3F) and LCD size
LiquidCrystal_I2C lcd(0x27, 16, 2);

// Photodiode analog output pin
const int photodiodePin = A0;

void setup() {
  lcd.init();         // Initialize the LCD
  lcd.backlight();    // Turn on the backlight

  lcd.setCursor(0, 0);
  lcd.print("Light Intensity:");
}

void loop() {
  int rawValue = analogRead(photodiodePin);
  int lightValue = 1023 - rawValue; // Invert so more light = higher number

  lcd.setCursor(0, 1);
  lcd.print("Level: ");
  lcd.print(lightValue);
  lcd.print("    "); // Clear leftover digits

  delay(500); // Update twice per second
}