#include <DHT.h>
#include <WiFi.h>
#include <HTTPClient.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>

#define DHTPIN 4          // DHT22 sensor pin
#define DHTTYPE DHT22     // DHT11/22 sensor type
#define MQ135_PIN 34      // MQ-135 sensor pin

const char* ssid = "Wokwi-GUEST"; // Wifi name
const char* password = "";        // Wifi password
const char* webAppUrl = "https://script.google.com/macros/s/AKfycbwUbDc5MMKbPqmc6o--EY8-qeTMvqVhzEswVwlG7ngjiRfv_Z065nVzjCqvHBWMaonbzA/exec";  // Replace with your actual web app URL

DHT dht(DHTPIN, DHTTYPE);
LiquidCrystal_I2C lcd(0x27, 20, 4);  // Address 0x27 for 20x4 LCD

void setup() {
  Serial.begin(115200);
  delay(100);

  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
    lcd.setCursor(0, 0);
    lcd.print("Connecting to WiFi...");
  }

  Serial.println("Connected to WiFi..ok");
  lcd.setCursor(0, 0);
  lcd.print("Connected to WiFi...ok  ");

  dht.begin();
  lcd.init();
  lcd.backlight();

  lcd.setCursor(0, 0);
  lcd.print("Temperature & Humidity");
  lcd.setCursor(0, 1);
  lcd.print("Initializing...");
}

void loop() {
  float humidity = dht.readHumidity();
  float temperature = dht.readTemperature();
  int adcValue = analogRead(MQ135_PIN);
  float voltage = adcValue * (3.3 / 4095.0);

  if (isnan(humidity) || isnan(temperature)) {
    Serial.println("Failed to read from DHT sensor");
    lcd.setCursor(0, 2);
    lcd.print("Sensor Error      ");
    delay(2000);
    return;
  }

  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.print(" °C, Humidity: ");
  Serial.print(humidity);
  Serial.print(" %, Gas ADC: ");
  Serial.print(adcValue);
  Serial.print(", Gas Volt: ");
  Serial.print(voltage);
  Serial.println(" V");

  // Display values on LCD
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Temp: ");
  lcd.print(temperature);
  lcd.print(" C  ");
  
  lcd.setCursor(0, 1);
  lcd.print("Humidity: ");
  lcd.print(humidity);
  lcd.print(" %  ");

  lcd.setCursor(0, 2);
  lcd.print("Gas ADC: ");
  lcd.print(adcValue);

  lcd.setCursor(0, 3);
  lcd.print("Gas Volt: ");
  lcd.print(voltage, 2);
  lcd.print(" V");

  // Send data to Google Apps Script
  sendDataToScript(temperature, humidity, adcValue, voltage);

  delay(2000); // Delay for 2 seconds
}

void sendDataToScript(float temperature, float humidity, int adcValue, float voltage) {
  HTTPClient http;
  String serverPath = String(webAppUrl) + "?temperature=" + String(temperature) + "&humidity=" + String(humidity) + "&adcValue=" + String(adcValue) + "&voltage=" + String(voltage);

  Serial.print("Connecting to server: ");
  Serial.println(serverPath);

  lcd.setCursor(0, 1);
  lcd.print("Sending data...    ");

  if (http.begin(serverPath)) {
    int httpCode = http.GET();
    if (httpCode > 0) {
      Serial.print("Server response code: ");
      Serial.println(httpCode);
      lcd.setCursor(0, 1);
      lcd.print("Data sent          ");
    } else {
      Serial.print("HTTP GET request failed with error code: ");
      Serial.println(httpCode);
      lcd.setCursor(0, 1);
      lcd.print("Send failed        ");
    }
    http.end();
  } else {
    Serial.println("Unable to connect to the server");
    lcd.setCursor(0, 1);
    lcd.print("Server connect err ");
  }
}