#define BLYNK_PRINT Serial
#define BLYNK_TEMPLATE_ID "TMPL3ulohk-WI"
#define BLYNK_TEMPLATE_NAME "ServoSenseBlynk"
#define BLYNK_AUTH_TOKEN "BTdLJWZxFfUhtOo9JsVzFTZ-enqiTR-8"
#include <WiFi.h>
#include <WiFiClient.h>
#include <BlynkSimpleEsp32.h>

#define TRIGGER_PIN  2
#define ECHO_PIN     4
#define SERVO_PIN    13

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

BlynkTimer timer;

int servoPos = 0;
int servoIncrement = 1;
int maxServoPos = 180;
int minServoPos = 0;

void setup() {
  Serial.begin(9600); // Initialize serial port for debugging
  Blynk.begin(auth, ssid, pass);

  pinMode(TRIGGER_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  
  ledcSetup(0, 50, 16);
  ledcAttachPin(SERVO_PIN, 0);
  
  timer.setInterval(1000L, sendSensorData);
}

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

void sendSensorData() {
  long duration, distance;
  
  digitalWrite(TRIGGER_PIN, LOW);
  delayMicroseconds(2);
  
  digitalWrite(TRIGGER_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIGGER_PIN, LOW);
  
  duration = pulseIn(ECHO_PIN, HIGH);
  
  distance = duration * 0.034 / 2;
  
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  Blynk.virtualWrite(V1, distance);

  // Control the servo motor based on the distance
  if (distance < 10) {
    servoIncrement = 1;
  } else if (distance > 50) {
    servoIncrement = -1;
  }
  
  servoPos += servoIncrement;
  servoPos = constrain(servoPos, minServoPos, maxServoPos);

  // Move the servo motor
  ledcWrite(0, servoPos);

  // Print servo position to Serial Monitor
  Serial.print("Servo Position: ");
  Serial.println(servoPos);
}