#include <ESP32Servo.h>


const byte trig_pin = 12;
const byte echo_pin = 26;
const byte servo_pin = 19;
const byte led_pin = 21;

Servo servo;

void setup() {

  pinMode(trig_pin, OUTPUT);
  pinMode(echo_pin, INPUT);
  pinMode(led_pin, OUTPUT);

  servo.attach(servo_pin);

 
  Serial.begin(115200);
}

void loop() {

  long int distance = get_distance();

  if (distance <= 15) {
    Serial.println("Sanitizer ON");
    servo.write(180);
    digitalWrite(led_pin, HIGH);
  }
  else {
    Serial.println("Sanitizer OFF");
    servo.write(0);
    digitalWrite(led_pin, LOW);
  }

  delay(10);
}


int get_distance() {


  digitalWrite(trig_pin, LOW);
  delayMicroseconds(2);

  digitalWrite(trig_pin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trig_pin, LOW);

  long int duration = pulseIn(echo_pin, HIGH);

  long int distance = (duration * 0.034) / 2;

  return distance;
}