#include <ESP32Servo.h>
#include <WiFi.h>
#include<ThingSpeak.h>
#include <NTPClient.h>
#include<time.h>
#define TRIG_PIN  23  
#define ECHO_PIN  22  
#define SERVO_PIN 26  
#define DISTANCE_THRESHOLD  60

Servo servo; 
char ssid[] = "Wokwi-GUEST";
char pass[] = "";
int servoPin123 = 3;
 WiFiClient client;
 unsigned long myChannelNumber = 2489652;
const char * myWriteAPIKey ="EMS8J1U7L7PKZPV7";
int statusCode;

WiFiUDP ntpUDP;
NTPClient timeClient(ntpUDP, "pool.ntp.org", 19800, 60000);

// variables will change:
float duration_us, distance_cm;

void setup() {
  Serial.begin (9600);      
  pinMode(TRIG_PIN, OUTPUT); 
  pinMode(ECHO_PIN, INPUT);  
  servo.attach(SERVO_PIN);   
  servo.write(0);
}

void wificonnection(){
  Serial.println("Attempting to connect");  
  while (WiFi.status() != WL_CONNECTED) {
    WiFi.begin(ssid, pass);
    Serial.print(".");
    delay(1000);
  }
}

void channelupdation()
{
  if(statusCode == 200) { //successful writing code
Serial.println("Channel update successful.");
}
else {
Serial.println("Problem Writing data. HTTP error code :" +
String(statusCode));
}
}

void loop() {
  // generate 10-microsecond pulse to TRIG pin
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);

 
  duration_us = pulseIn(ECHO_PIN, HIGH);

  distance_cm = 10 * duration_us;

  if (distance_cm < DISTANCE_THRESHOLD)
    servo.write(90);
  else
    servo.write(0); 

  Serial.print("distance: ");
  Serial.print(distance_cm);
  Serial.println(" cm");
  Serial.println("<-------------------------------------->");

  delay(500);

  
  ThingSpeak.setField(1, distance_cm);
  ThingSpeak.setField(2, duration_us);
statusCode = ThingSpeak.writeFields(myChannelNumber,myWriteAPIKey);
 
 channelupdation(); 
  delay(1500);

}