#include <ESP32Servo.h>

// Define pins
const int trigPin = 14;
const int echoPin = 12;
const int ledPin = 13;
Servo myServo;

// Variables for distance measurement
long duration;
int distance;

void setup() {
  // Initialize serial communication
  Serial.begin(9600);
  
  // Set pin modes
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(ledPin, OUTPUT);
  
  // Attach the servo to pin 11
  myServo.attach(15);
}

void loop() {
  // Sweep the servo from 0 to 180 degrees
  for (int pos = 0; pos <= 180; pos += 1) {
    myServo.write(pos);
    delay(15);
    measureDistance();
  }
  
  // Sweep the servo from 180 to 0 degrees
  for (int pos = 180; pos >= 0; pos -= 1) {
    myServo.write(pos);
    delay(15);
    measureDistance();
  }
}

void measureDistance() {
  // Clear the trigPin
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  
  // Set the trigPin on HIGH state for 10 microseconds
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  
  // Read the echoPin, returns the sound wave travel time in microseconds
  duration = pulseIn(echoPin, HIGH);
  
  // Calculate the distance
  distance = duration * 0.034 / 2;
  
  // Print the distance on the Serial Monitor
  Serial.print("Distance: ");
  Serial.println(distance);
  
  // Turn on the LED if an object is within 50 cm
  if (distance < 50) {
    digitalWrite(ledPin, HIGH);
  } else {
    digitalWrite(ledPin, LOW);
  }
}