/*
  MQUnifiedsensor Library - reading an MQ2

  Demonstrates the use a MQ2 sensor.
  Library originally added 01 may 2019
  by Miguel A Califa, Yersson Carrillo, Ghiordy Contreras, Mario Rodriguez
 
  Added example
  modified 23 May 2019
  by Miguel Califa 

  Updated library usage
  modified 26 March 2020
  by Miguel Califa 
  Wiring:
  https://github.com/miguel5612/MQSensorsLib_Docs/blob/master/static/img/MQ_Arduino.PNG
  Please make sure arduino A0 pin represents the analog input configured on #define pin

 This example code is in the public domain.

*/
#include <WiFi.h>
#include "ThingSpeak.h"
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <MQUnifiedsensor.h>

//Include the library

/************************Hardware Related Macros************************************/

LiquidCrystal_I2C lcd(0x27, 16, 2);
const char* WIFI_NAME = "Wokwi-GUEST"; // WiFi SSID
const char* WIFI_PASSWORD = ""; // WiFI Password
const int myChannelNumber = 2891570; // ThingSpeak channel number
const char* myApiKey = "X01433VB0TH5RMD8"; // ThingSpeak API key
const char* server = "api.thingspeak.com"; // ThingSpeak server address
const int mq7Pin = 35;  // GPIO35
const int LED_PIN = 13;
const int LED = 26;
const int buzzer = 25;


// Create an instance of the DHTesp library
// Create a WiFi client object
WiFiClient client; 
void setup() {
  Serial.begin(115200);
 pinMode(LED_PIN, OUTPUT);
 pinMode(LED, OUTPUT);
 pinMode(buzzer, OUTPUT);
  // Initialize the LCD
  lcd.init();
  lcd.backlight();
  
  // Print a message to the LCD.
  lcd.setCursor(0, 0);
  lcd.print("MQ7 Sensor");
  delay(2000);
      WiFi.begin(WIFI_NAME, WIFI_PASSWORD); // Connect to the WiFi network
  while (WiFi.status() != WL_CONNECTED){
    delay(1000);
    Serial.println("Wifi not connected"); // Print a message if WiFi is not connected
  }
  Serial.println("Wifi connected !"); // Print a message if WiFi is connected
  Serial.println("Local IP: " + String(WiFi.localIP())); // Print the local IP address
  WiFi.mode(WIFI_STA); // Set the WiFi mode to station mode
  ThingSpeak.begin(client); // Initialize the ThingSpeak library
}

void loop() {
   int mq7Value = analogRead(mq7Pin);
   mq7Value = map(mq7Value, 0, 4095, 0, 100);
    Serial.println("MQ-7 Value: ");
  Serial.println(mq7Value);
     
  // Display sensor values on the LCD
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("MQ-7: ");
  lcd.print(mq7Value);
  lcd.setCursor(0, 1);
      
  // Wait for a while before reading the values again
  
 // Wait for a while before reading the values again
  delay(1000);
  // Read temperature and humidity from the DHT22 sensor
   // Set the value of field 1 in the ThingSpeak channel to the temperature
    // Set the value of field 2 in the ThingSpeak channel to the humidity 
  
  // Write the data to the ThingSpeak channel
               
   
  ThingSpeak.setField(1, mq7Value);
  ThingSpeak.setField(2, mq7Value);
  if (mq7Value > 35) {
    digitalWrite(buzzer, HIGH);
    digitalWrite(LED_PIN, HIGH);
    digitalWrite(LED, HIGH);
    delay(1000);
        
    
  } else {
    digitalWrite(LED_PIN, LOW);
    digitalWrite(LED, LOW);
  }

  int x = ThingSpeak.writeFields(myChannelNumber, myApiKey);
     
  Serial.println("Gas Value: " + String(mq7Value));
    
  if (x == 200) {
    Serial.println("Data pushed successfully");
  } else {
    Serial.println("Push error: " + String(x));
  }
  Serial.println("---");

  delay(10000);
}