#define BLYNK_TEMPLATE_ID "TMPL3hVLYsR30"
#define BLYNK_TEMPLATE_NAME "Abdul Kaiz"
#define BLYNK_AUTH_TOKEN "vKAlp0SCWZY9BhzRPYKrgXONNbCzDOc5"

#define BLYNK_PRINT Serial

#include <WiFi.h>
#include <WiFiClient.h>
#include <BlynkSimpleEsp32.h>

// Define pin connections
const int pin_trig1 = 22;
const int pin_echo1 = 23;
const int pin_echo2 = 27;
const int pin_trig2 = 26;

int distance1; // Front distance
int distance2; // Back distance
int stepPerRevolution = 200;

const int dirPin[] = {5, 12, 18, 33};
const int stepPin[] = {4, 13, 19, 32}; 

char auth[] = "vKAlp0SCWZY9BhzRPYKrgXONNbCzDOc5";
char ssid[] = "Wokwi-GUEST";
char pass[] = "";

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

  // Ultrasonic sensor pin modes
  pinMode(pin_trig1, OUTPUT);
  pinMode(pin_echo1, INPUT);
  pinMode(pin_echo2, INPUT);
  pinMode(pin_trig2, OUTPUT);

  // Stepper motor pin modes
  for (int i = 0; i < 4; i++) {
    pinMode(stepPin[i], OUTPUT);
    pinMode(dirPin[i], OUTPUT);
  }

  Blynk.begin(auth, ssid, pass);
}

void loop() {
  Blynk.run();

  // Front ultrasonic sensor
  digitalWrite(pin_trig1, LOW);
  delayMicroseconds(2);
  digitalWrite(pin_trig1, HIGH);
  delayMicroseconds(10);
  digitalWrite(pin_trig1, LOW);
  distance1 = pulseIn(pin_echo1, HIGH) * 0.034 / 2;

  // Back ultrasonic sensor
  digitalWrite(pin_trig2, LOW);
  delayMicroseconds(2);
  digitalWrite(pin_trig2, HIGH);
  delayMicroseconds(10);
  digitalWrite(pin_trig2, LOW);
  distance2 = pulseIn(pin_echo2, HIGH) * 0.034 / 2;

  Serial.print("FRONT-DISTANCE = ");
  Serial.print(distance1);
  Serial.print(" BACK-DISTANCE = ");
  Serial.println(distance2);

  delay(100);

  // Send distance values to Blynk
  Blynk.virtualWrite(V0, distance1);
  delay(1000);
  Blynk.virtualWrite(V1, distance2);
  delay(1000);

  // Stepper motor control based on distance
  if (distance1 > 20) { // Move forward if distance is greater than 20cm
    for (int i = 0; i < 4; i++) {
      digitalWrite(dirPin[i], HIGH); // Set direction pins to HIGH for forward movement
    }
    for (int i = 0; i < stepPerRevolution; i++) {
      for (int j = 0; j < 4; j++) {
        digitalWrite(stepPin[j], HIGH);
        delay(1);
        digitalWrite(stepPin[j], LOW);
        delay(1);
      }
    }
  } else { // Move backward if distance is less than or equal to 20cm
    for (int i = 0; i < 4; i++) {
      digitalWrite(dirPin[i], LOW); // Set direction pins to LOW for backward movement
    }
    for (int i = 0; i < stepPerRevolution; i++) {
      for (int j = 0; j < 4; j++) {
        digitalWrite(stepPin[j], HIGH);
        delay(1);
        digitalWrite(stepPin[j], LOW);
        delay(1);
      }
    }
  }
}