// #include "Ultrasonic.h"
// const int TRIGGER_PIN = 7;
// const int ECHO_PIN = 8;
// Ultrasonic ultrasonic (TRIGGER_PIN, ECHO_PIN);
// int distance;
// void setup() {
// Serial.begin(9600);
// }

// void loop() {
// distance = ultrasonic.read(CM);
// if (distance >= 0 && distance <= 400) 
// { 
//   Serial.print("Distance in CM: "); Serial.println(distance);
// } 
// else 
// {
//  Serial.println("Out of Range");
// }
// delay(1000);
// }

// #include <Wire.h>
// #include <LiquidCrystal_I2C.h>
// LiquidCrystal_I2C lcd (0x27, 16, 2);
// #include "Ultrasonic.h"
// const int TRIGGER_PIN = 7;
// const int ECHO_PIN = 8;
// Ultrasonic ultrasonic (TRIGGER_PIN, ECHO_PIN);
// int distance;

// void setup() {
//  lcd.init();
// lcd.backlight();
// }

// void loop() {
// distance = ultrasonic.read(CM);
// lcd.clear();
// if (distance>= 2 && distance <= 5) {
// lcd.setCursor(0, 0);
// lcd.print("Too Close!");
// } 
// else if (distance> 5 && distance < 380) {
// lcd.setCursor(0, 0);
// lcd.print("Distance: "); lcd.print(distance);
// lcd.print("cm");
// } 
// else {
// lcd.setCursor(0, 0);
// lcd.print("Out of Range");
// }
// delay(1000);
// }


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

const int TRIGGER_PIN = 7;
const int ECHO_PIN = 8;
Ultrasonic ultrasonic(TRIGGER_PIN, ECHO_PIN);
LiquidCrystal_I2C lcd (0x27, 16, 2);
const int GREEN_LED = 2;
const int YELLOW_LED = 3;
const int RED_LED = 4;
int distance;

void setup() {
  lcd.init();
  lcd.backlight();

  pinMode(GREEN_LED, OUTPUT);
  pinMode(YELLOW_LED, OUTPUT);
  pinMode(RED_LED, OUTPUT);
}

void loop() {
  distance = ultrasonic.read(CM);
  lcd.clear();

  Serial.print("Distance: ");
  Serial.println(distance);

  if (distance > 15) {
    lcd.setCursor(0, 0);
    lcd.print("Green LED ON");
    digitalWrite(GREEN_LED, HIGH);
    digitalWrite(YELLOW_LED, LOW);
    digitalWrite(RED_LED, LOW);
  } else if (distance >= 5 && distance <= 15) {
    lcd.setCursor(0, 0);
    lcd.print("Yellow LED ON");
    digitalWrite(GREEN_LED, LOW);
    digitalWrite(YELLOW_LED, HIGH);
    digitalWrite(RED_LED, LOW);
  } else if (distance < 5) {
    lcd.setCursor(0, 0);
    lcd.print("Red LED ON");
    digitalWrite(GREEN_LED, LOW);
    digitalWrite(YELLOW_LED, LOW);
    digitalWrite(RED_LED, HIGH);
    buzzerSound();
  }

  delay(1000);
}

void buzzerSound() {
  for (int i = 0; i < 3; ++i) {
    delay(100);
    delay(100);
  }
  delay(1000);
}