#include <WiFi.h>
#include <PubSubClient.h>
#include <DHT.h>

// Wifi
const char* ssid = "Wokwi-GUEST";
const char* password = "";

// MQTT Broker
const char* mqtt_server = "broker.emqx.io";
const int mqtt_port = 1883;
const char* mqtt_username = "emqx";
const char* mqtt_password = "public";
const char* topic = "emqx/zahid";

// DHT Sensor
#define DHTPIN 4  // Define the pin where the DHT22 sensor is connected
#define DHTTYPE DHT11  // Define the type of DHT sensor

WiFiClient espClient;
PubSubClient client(espClient);
DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(9600);

  WiFi.begin(ssid, password);

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

  // Initialize MQTT connection
  client.setServer(mqtt_server, mqtt_port);
  client.setCallback(callback);

  while (!client.connected()) {
    String client_id = "esp32-client-";
    client_id += WiFi.macAddress();
    Serial.printf("The Client %s connects to public MQTT broker\n", client_id.c_str());
    if (client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {
      Serial.println("Public EMQX MQTT Broker connected");
    } else {
      Serial.print("Failed with state ");
      Serial.print(client.state());
      delay(2000);
    }
  }

  dht.begin();  // Initialize the DHT sensor
}

void callback(char* topic, byte* payload, unsigned int length) {
  Serial.print("Message arrived in topic: ");
  Serial.println(topic);
  Serial.print("Message: ");
  for (int i = 0; i < length; i++) {
    Serial.print((char)payload[i]);
  }
  Serial.println();
}

void loop() {
  client.loop();

  // Read DHT sensor data
  float humidity = dht.readHumidity();
  float temperature = dht.readTemperature();

  // Check if reading was successful
  if (isnan(humidity) || isnan(temperature)) {
    Serial.println("Failed to read from DHT sensor!");
    delay(2000);
    return;
  }

  // Publish temperature and humidity to MQTT broker
  String temperatureString = String(temperature, 2);
  String humidityString = String(humidity, 2);

  client.publish("emqx/Temperature", temperatureString.c_str());
  client.publish("emqx/Humidity", humidityString.c_str());

  delay(5000); // Adjust the delay as needed for your application
}