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

const char* ssid = "Wokwi-GUEST";          // Replace with your Wi-Fi SSID
const char* password = "";  // Replace with your Wi-Fi password
const unsigned long myChannelNumber = 2723102;  // Replace with your ThingSpeak Channel ID
const char* myWriteAPIKey = "IYD7X33S61Q35DOL";  // Replace with your ThingSpeak Write API Key

// Pin Definitions
const int methanepin = 34;        // MQ2 sensor connected to pin 34 (ADC pin)
const int smokepin = 35;
const int redLED = 14;         // Red LED connected to pin 14
const int greenLED = 13;       // Green LED connected to pin 13
const int buzzerPin = 22;      // Buzzer connected to pin 22

WiFiClient client;

void setup() {
  Serial.begin(115200);

  // Initialize LED and Buzzer pins
  pinMode(redLED, OUTPUT);
  pinMode(greenLED, OUTPUT);
  pinMode(buzzerPin, OUTPUT);
  pinMode(methanepin, INPUT);
  pinMode(smokepin,INPUT);

  // Connect to Wi-Fi
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");

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

void loop() {
  // Read the MQ2 gas sensor value from pin 34
  int methane = analogRead(methanepin);  // Declare and assign the correct sensor reading
  Serial.print("MQ2 Sensor Value: ");
  Serial.println(methane);
  int smoke = analogRead(smokepin);  // Declare and assign the correct sensor reading
  Serial.print("MQ2 Sensor Value: ");
  Serial.println(smoke);

  // Control LEDs and Buzzer based on gas sensor value
  if (methane > 50) {  // Smoke detected
    digitalWrite(redLED, HIGH);  // Turn on red LED
    digitalWrite(greenLED, LOW); // Turn off green LED
    digitalWrite(buzzerPin, HIGH);  // Turn on buzzer (alert)
    Serial.println("methane detected! Buzzer ON");
    tone(buzzerPin, 1000);
  } 
  else {digitalWrite(redLED, HIGH);  // Turn on red LED
    digitalWrite(greenLED, LOW); // Turn off green LED
    digitalWrite(buzzerPin, HIGH);  // Turn on buzzer (alert)
    Serial.println("methane detected! Buzzer ON");
    tone(buzzerPin, 1000);
  } 
 
 if (smoke  < 70) {  // Smoke detected
    digitalWrite(redLED, LOW);  // Turn on red LED
    digitalWrite(greenLED, HIGH); // Turn off green LED
    digitalWrite(buzzerPin, HIGH);  // Turn on buzzer (alert)
    Serial.println("Smoke detected! Buzzer ON");
    tone(buzzerPin, 1000);
  }

  else {  // No significant gas detected
    digitalWrite(redLED, LOW);   // Turn off red LED
    digitalWrite(greenLED, LOW); // Turn on green LED
    digitalWrite(buzzerPin, LOW); // Turn off buzzer
    Serial.println("Normal conditions, no gas detected.");
  }

  // Send sensor data to ThingSpeak
  ThingSpeak.setField(1, methane); // Set the field value for gas sensor
  ThingSpeak.setField(2, smoke);
  ThingSpeak.writeFields(myChannelNumber, myWriteAPIKey);

  delay(1000);  // Wait for 2 seconds before sending the next data
}