#include <WiFi.h>
#include <ThingSpeak.h>
const int ledPin= 15;
const int trig = 5;
const int echo = 18;
float distance;
long duration;

char ssid[] = "Wokwi-GUEST";
char pass[] = "";
WiFiClient client;
//WiFi initialization

long int mychannelid = 2711602;
char mywriteapi[] = "UMRFCEZ0YOIEWK7T";
//Thingspeak initialization

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
 
  pinMode(trig, OUTPUT);
  pinMode(echo, INPUT);

  pinMode(ledPin, OUTPUT);

  WiFi.mode(WIFI_STA);

  Serial.print("Attempting to connect");
  while(WiFi.status() != WL_CONNECTED)
  {
    WiFi.begin(ssid,pass);
    Serial.print(".");
    delay(5000);
  }
  Serial.println("\nConnected");
  //wifi setup

  ThingSpeak.begin(client);
  //thingspeak setup
}
long getdistance(){
  digitalWrite(trig, LOW);
  delayMicroseconds(2);
  digitalWrite(trig, HIGH);
  delayMicroseconds(10);
  digitalWrite(trig, LOW);
  duration = pulseIn(echo, HIGH);
  return(duration*0.034/2);
}
void loop() 
{
 distance = getdistance();
 Serial.println(distance);
 if(distance > 200)
{
  analogWrite(ledPin,125);
  ThingSpeak.setField(2,0);
}
else{
  analogWrite(ledPin,255);
  ThingSpeak.setField(2,1);
}
  ThingSpeak.setField(1,distance);
  int statuscode = ThingSpeak.writeFields(mychannelid,mywriteapi);
  if(statuscode == 200)
    Serial.println("Data uploaded");
  else
    Serial.println("Problem writing data");
  delay(15000);
}