#include <ESP32Servo.h>

#define TRIG_PIN 5
#define ECHO_PIN 18
#define SERVO_PIN 13
#define BUZZER_PIN 27
#define LED_G_PIN 22
#define LED_R_PIN 23
Servo myServo;

long duration;
float distance;

void setup() {
  Serial.begin(115200);

  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
 pinMode(LED_G_PIN, OUTPUT);
 pinMode(LED_R_PIN, OUTPUT);

  myServo.attach(SERVO_PIN);
  myServo.write(0);
}

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

  duration = pulseIn(ECHO_PIN, HIGH, 30000);

  if (duration == 0) {
    Serial.println("No object");
    return;
  }

  distance = duration * 0.034 / 2;

  Serial.println(distance);

  if (distance > 0 && distance < 20) {{
    myServo.write(90);
    tone(BUZZER_PIN, 1000);
    digitalWrite(LED_G_PIN,LOW);
    for (int i = 0; i < 5; i++) {
    
        digitalWrite(LED_R_PIN, HIGH);
    delay(50);
    digitalWrite(LED_R_PIN, LOW);
    delay(50);
  }
  
  } }else if (distance >= 25) {
    myServo.write(0);
    noTone(BUZZER_PIN);
    digitalWrite(LED_G_PIN,HIGH);
    digitalWrite(LED_R_PIN,LOW);
  }

  delay(300);
}