//LCD
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);  // Address 0x27, 16 chars, 2 lines

//Servo
#include <Servo.h>
Servo S;

//HC
const int trigPin = 9;
const int echoPin = 8;

long duration;
int distance;

//LED
const int ledGreen = 3;
const int ledYellow = 4;
const int ledRed = 5;


void setup() {
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(ledGreen, OUTPUT);
  pinMode(ledYellow, OUTPUT);
  pinMode(ledRed, OUTPUT);

 S.attach(10);

  lcd.begin(16, 2);
  lcd.backlight();
  Serial.begin(9600);
}

void loop() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  duration = pulseIn(echoPin, HIGH);
  distance = duration * 0.034 / 2;

  lcd.setCursor(0, 0);
  lcd.print("distance: ");
  lcd.print(distance);
  lcd.print(" cm");

  if (distance >= 0 && distance <= 150) {
    digitalWrite(ledGreen, HIGH);
    digitalWrite(ledYellow, LOW);
    digitalWrite(ledRed, LOW);
    lcd.setCursor(0, 1);
    lcd.print("Close");
    S.write(0);
  } 
  else if (distance > 150 && distance <= 300) {
    digitalWrite(ledGreen, LOW);
    digitalWrite(ledYellow, HIGH);
    digitalWrite(ledRed, LOW);
    lcd.setCursor(0, 1);
    lcd.print("Normal");
    S.write(90);
  } 
  else if (distance > 300) {
    digitalWrite(ledGreen, LOW);
    digitalWrite(ledYellow, LOW);
    digitalWrite(ledRed, HIGH);
    lcd.setCursor(0, 1);
    lcd.print("Long");
    S.write(180);
  } 
  else {
    digitalWrite(ledGreen, LOW);
    digitalWrite(ledYellow, LOW);
    digitalWrite(ledRed, LOW);
    lcd.setCursor(0, 1);
    lcd.print("404 Not Found");
    S.write(270);
  }

  delay(500);
}