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


const char* ssid = "Wokwi-GUEST";
const char* pass = "";
const char* myWriteAPIKey = "7NXWEDLHKUGLU6PY";
const unsigned long myChannelNumber = 3043774;

WiFiClient client;

const int ledPin = 18;
const int trigPin = 5;
const int echoPin = 19;
const int ldrPin = 17;

// Sensor variables
float pingTime, distanceCM;
int ldrValue;

void setup() {
  Serial.begin(115200);
  WiFi.mode(WIFI_STA);
  ThingSpeak.begin(client);

  pinMode(ledPin, OUTPUT);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(ldrPin, INPUT);

  Serial.println("ESP32 Setup Complete.");
}

void loop() {
  // WiFi Reconnect Logic
  if (WiFi.status() != WL_CONNECTED) {
    Serial.println("Connecting to Wi-Fi...");
    while (WiFi.status() != WL_CONNECTED) {
      WiFi.begin(ssid, pass);
      Serial.print(".");
      delay(5000);
    }
    Serial.println("\nConnected.");
  }

  // LDR Reading
  ldrValue = digitalRead(ldrPin); // 0 = Dark, 1 = Light

  // Distance Measurement
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

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

  Serial.print("Distance (cm): ");
  Serial.println(distanceCM);
  Serial.print("LDR Value: ");
  Serial.println(ldrValue);

  // LED Logic
  if (distanceCM <= 100 && ldrValue == 0) {
    digitalWrite(ledPin, HIGH);
  } else {
    digitalWrite(ledPin, LOW);
  }

  // Send to ThingSpeak
  ThingSpeak.setField(1, distanceCM);
  ThingSpeak.setField(2, ldrValue);

  int x = ThingSpeak.writeFields(myChannelNumber, myWriteAPIKey);

  if (x == 200) {
    Serial.println("Data sent to ThingSpeak.");
  } else {
    Serial.println("ThingSpeak Error: " + St