#include <WiFi.h>
#include <ThingSpeak.h>
const char* ssid = "Wokwi-GUEST";
const long channel =3063003 ;
const char* key = "7J7NY69DIDZWP87S";
const byte trig = 5, echo = 18, led = 15;
WiFiClient client;
unsigned long lastTime;
float distance;
void setup(){
  Serial.begin(115200);
  pinMode(trig, OUTPUT);
  pinMode(echo, INPUT);
  pinMode(led, OUTPUT);
  WiFi.begin(ssid);
  ThingSpeak.begin(client);
}
void loop(){
  digitalWrite(trig, HIGH);
  delayMicroseconds(10);
  digitalWrite(trig, LOW);
  distance = pulseIn(echo, HIGH)*0.017;
  bool ledState = distance < 50;
  digitalWrite(led, ledState);
  Serial.println(ledState ? "LED ON" : "LED OFF");
  if(millis()-lastTime > 30000){
     ThingSpeak.setField(1,distance);
     ThingSpeak.setField(2,ledState);
     ThingSpeak.writeFields(channel,key);  
     lastTime = millis();
  }
  delay(1000);
  }