#include <WiFi.h>
#include <HTTPClient.h>

// Replace with your WiFi credentials
const char* ssid = "Your_SSID";
const char* password = "Your_PASSWORD";

// Replace with your ThingSpeak API Key
const char* apiKey = "QACOOKB4NUAMU5A6";
const char* server = "http://api.thingspeak.com/update";

// Define MQ-2 pin
const int mq2Pin = 34; // Analog pin connected to MQ-2 sensor output

void setup() {
  Serial.begin(115200);
  WiFi.begin(ssid, password);

  Serial.print("Connecting to WiFi");
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nConnected to WiFi");
}

void loop() {
  int gasValue = analogRead(mq2Pin); // Read the analog value from MQ-2
  Serial.print("Gas Value: ");
  Serial.println(gasValue);

  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;

    String url = String(server) + "?api_key=" + apiKey + "&field1=" + String(gasValue);
    http.begin(url);

    int httpResponseCode = http.GET();

    if (httpResponseCode > 0) {
      Serial.print("HTTP Response Code: ");
      Serial.println(httpResponseCode);
      if (httpResponseCode == 200) {
        Serial.println("Data successfully sent to ThingSpeak.");
      }
    } else {
      Serial.print("Error Code: ");
      Serial.println(httpResponseCode);
    }

    http.end();
  } else {
    Serial.println("WiFi Disconnected");
  }

  delay(20000); // ThingSpeak allows updates every 15 seconds
}