#define BLYNK_TEMPLATE_ID "TMPL3DZFrPqev"
#define BLYNK_TEMPLATE_NAME "virtual reality navigation"
#define BLYNK_AUTH_TOKEN "pi8JXHs1X6dh7vUqoX6eflsRKHkKSqsR"
#include <WiFi.h>
#include <WiFiClient.h>
#include <BlynkSimpleEsp32.h>
#include <LiquidCrystal_I2C.h>

#define BLYNK_PRINT Serial

// Set up Wi-Fi credentials
char auth[] = "Wokwi";  // You'll get this from the Blynk app
char ssid[] = "Wokwi-GUEST";
char pass[] = "";

// Set up LCD
LiquidCrystal_I2C lcd(0x27, 16, 2);  // Change the address if necessary

// Set up ultrasonic sensor pins
const int trigPin = 12;
const int echoPin = 13;

// Set up tactile feedback device pins
const int tactileFeedbackPin = 26;

// Virtual pin for Blynk
#define VIRTUAL_PIN_DISTANCE V2

void setup() {
  Serial.begin(9600);
  Blynk.begin(auth, ssid, pass);
  lcd.init();
  lcd.backlight();
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(tactileFeedbackPin, OUTPUT);
}

void loop() {
  Blynk.run();
  detectObstacle();
}

void detectObstacle() {
  long duration, distance;
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distance = (duration * 0.0343) / 2;
  lcd.setCursor(0, 0);
  lcd.print("Distance: ");
  lcd.print(distance);
  lcd.print(" cm   ");
  
  // Send distance data to Blynk app
  Blynk.virtualWrite(VIRTUAL_PIN_DISTANCE, distance);
  
  // If obstacle is detected within a certain range, trigger the tactile feedback device
  if (distance < 20) {
    digitalWrite(tactileFeedbackPin, HIGH);
    delay(1000); // Adjust as needed
    digitalWrite(tactileFeedbackPin, LOW);
  }
  
  delay(500); // Adjust as needed
}