#include <WiFi.h>
#include "ThingSpeak.h" // always include thingspeak header file after other header files and custom macros


#define WIFI_SSID "Wokwi-GUEST"		// replace MySSID with your WiFi network name
#define WIFI_PASSWORD ""	// replace MyPassword with your WiFi password


#define SECRET_CH_ID 2107115			// replace 0000000 with your channel number
#define SECRET_WRITE_APIKEY "HTQHBS7VR2P6RXAM"   // replace XYZ with your channel write API Key
#define SECRET_READ_APIKEY "PAK7RC5WHG6D89IV"

#define MQ2 32 // define MQ2 analog pin
#define LED 27


WiFiClient  client;

unsigned long myChannelNumber = SECRET_CH_ID;
const char * myWriteAPIKey = SECRET_WRITE_APIKEY;
const char * myReadAPIKey = SECRET_READ_APIKEY;

int MQ2_value;

int LED_status;
unsigned long dataMillis = 0;

void setup() {
  Serial.begin(115200);  //Initialize serial

  pinMode(MQ2, INPUT);
  pinMode(LED, OUTPUT);
  digitalWrite(LED, LOW);

  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
  Serial.print("Connecting to Wi-Fi");
  while (WiFi.status() != WL_CONNECTED)
  {
    Serial.print(".");
    delay(300);
  }
  Serial.println();
  Serial.print("Connected with IP: ");
  Serial.println(WiFi.localIP());
  Serial.println();

  ThingSpeak.begin(client);  // Initialize ThingSpeak
}

void loop() {
  int statusCode = 0;
  MQ2_value = analogRead(MQ2);
  if (isnan(MQ2_value))
  {
    Serial.println("Failed to read from MQ-2 sensor!");
    return;
  }
  
  ThingSpeak.setField(1, MQ2_value);
  //ThingSpeak.setField(2, LED);

  // Check the status of the read operation to see if it was successful
  statusCode = ThingSpeak.readMultipleFields(myChannelNumber, myReadAPIKey) ;
  if(statusCode == 200)
  {
    // Fetch the stored data
    LED_status = ThingSpeak.getFieldAsInt(2); // Field 2
    //int LED2 = ThingSpeak.getFieldAsInt(3); // Field 3.....8

    Serial.println("LED Status:   " + String(LED_status));
    if(LED_status==1)
    {
      digitalWrite(LED,HIGH);
    }
    if(LED_status==0)
    {
      digitalWrite(LED,LOW);
    }
  }
  else{
    Serial.println("Problem reading channel. HTTP error code " + String(statusCode)); 
  }
 //////////////////////////////////////////////////////////////////////////////////////////
  if (millis() - dataMillis > 15000)
  {
    Serial.printf("Digital value: %d\n", MQ2_value);
    int x = ThingSpeak.writeFields(myChannelNumber, myWriteAPIKey);
    if(x == 200){
      Serial.println("Channel update successful.");
    }
    else {
      Serial.println("Problem updating channel. HTTP error code " + String(x));
    }  
  }  
}