#include <LiquidCrystal_I2C.h> // Include the LiquidCrystal_I2C library

LiquidCrystal_I2C lcd(0x27, 16, 2); // Initialize LCD: Address 0x27, 16 columns, 2 rows

const int DISPLAY_WIDTH = 16; // LCD width
unsigned long previousMillis = 0; // Stores the previous time
unsigned long interval = 600; // Scrolling interval in milliseconds
String inputMessage = ""; // Stores the message to be displayed
int scrollPosition = 0; // Current scrolling position

void setup() 
{
  lcd.init(); // Initialize the LCD
  lcd.backlight(); // Turn on the backlight
  Serial.begin(9600); // Initialize serial communication
  Serial.println("Start");
}

void loop() 
{
  // Check for serial input
  if (Serial.available() > 0) 
  {
    // Read the input message
    inputMessage = Serial.readStringUntil('\n');
    // Reset the scrolling position
    scrollPosition = 0;
    // Reset the scrolling timer
    previousMillis = millis();
  }

  // Check if it's time to scroll
  if (millis() - previousMillis >= interval) 
  {
    // Clear the LCD
    lcd.clear();
    
    // Print the input message without scrolling if it's 16 characters or less
    if (inputMessage.length() <= DISPLAY_WIDTH) 
    {
      lcd.setCursor(0, 0);
      lcd.print(inputMessage);
    } 
    else 
    {
      // Print the scrolling part of the message
      lcd.setCursor(0, 0);
      lcd.print(inputMessage.substring(scrollPosition, min(scrollPosition + DISPLAY_WIDTH, inputMessage.length())));

      // Increment the scrolling position
      scrollPosition++;

      // Wrap around if needed
      if (scrollPosition >= inputMessage.length()) 
      {
        scrollPosition = 0;
      }
    }
    
    // Update the scrolling timer
    previousMillis = millis();
  }
}