#include <Arduino.h>
#include <WiFi.h>
#include <ThingSpeak.h>
const char* ssid = "Wokwi-GUEST";
const char* pass = ""; 
const char* myWriteAPIKey = "NYO1MUOHHT9QTEHB
";
const unsigned long myChannelNumber = 3052480;

int led = 18, trigPin = 5, echoPin = 19;
float pingTime, targetDistance;

WiFiClient client;

void setup() {
  Serial.begin(115200); 
  WiFi.mode(WIFI_STA);
  ThingSpeak.begin(client);
  Serial.println("Hello, ESP32!");

  pinMode(led, OUTPUT);
  pinMode(trigPin, OUTPUT);
  pinMode(2, INPUT);
  pinMode(echoPin, INPUT);
}

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

  int ldr = digitalRead(17);
  digitalWrite(trigPin, LOW); 
  delayMicroseconds(2); 
  digitalWrite(trigPin, HIGH); 
  delayMicroseconds(10); 
  digitalWrite(trigPin, LOW); 
  delayMicroseconds(15);  

  pingTime = pulseIn(echoPin, HIGH); 
  targetDistance = (pingTime * 0.0343) / 2; 

  Serial.println(targetDistance);
  Serial.println(ldr);

  if ((targetDistance <= 100) && (ldr == 0)) {
    digitalWrite(led, HIGH);
  } else {
    digitalWrite(led, LOW);
  }
  ThingSpeak.setField(1, targetDistance);
  int statusCode = ThingSpeak.writeFields(myChannelNumber, myWriteAPIKey);
  if (statusCode == 200)
  {
    Serial.println("Channel update Successful! ");
  }
  else
  {
    Serial.print("Problem writing data. HTTP error code");
    Serial.println(statusCode);
  }
  delay(10); 
}