#include<WiFi.h>
#include<ThingSpeak.h>

char ssid[]="Wokwi-GUEST";// default user name for wifi
char pass[]="";
WiFiClient client;

unsigned long myChannelNumber = 2231178;
const char * myWriteAPIKey = "44G9HY60Q65XRSWC";

int statuscode;
const int pingPin = 5; // Trigger Pin of Ultrasonic Sensor
const int echoPin = 17; // Echo Pin of Ultrasonic Sensor

void setup() {
   Serial.begin(9600); // Starting Serial Terminal

   WiFi.mode(WIFI_STA); //connect to wifi simulator
  ThingSpeak.begin(client);  // connect to thingspeak
}

void loop() {
   long duration, inches, cm;
   pinMode(pingPin, OUTPUT);
   digitalWrite(pingPin, LOW);
   delayMicroseconds(2);
   digitalWrite(pingPin, HIGH);
   delayMicroseconds(10);
   digitalWrite(pingPin, LOW);
   pinMode(echoPin, INPUT);
   duration = pulseIn(echoPin, HIGH);
   inches = microsecondsToInches(duration);
   
   cm = microsecondsToCentimeters(duration);
   
   Serial.print(inches);
   Serial.print("inches, ");
   Serial.print(cm);
   Serial.print("cm");
   Serial.println();
   delay(400);

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

  ThingSpeak.setField(1, inches);
  ThingSpeak.setField(2, cm);
  statuscode = ThingSpeak.writeFields(myChannelNumber, myWriteAPIKey);

 if(statuscode == 200) //200 indicates success update
  {
     Serial.println("Channel Update Successful");
  }
  else
  {
    Serial.println("Problem in writing Data:" + String(statuscode));
  }
  delay(15000);
}

long microsecondsToInches(long microseconds) {                //user defined function
   
   return microseconds / 74 / 2;
}

long microsecondsToCentimeters(long microseconds) {          // user defined function
   
   return microseconds / 29 / 2;
}