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

#define DHTPIN 21         
#define DHTTYPE DHT22     


const char *SSID = "Wokwi-GUEST";
const char *PASSWORD = "";


const char *MQTTServer = "broker.emqx.io"; 
const char *MQTT_Topic = "webapp/Data";  
const char *MQTT_ID = "ESP32_DHT"; 
int Port = 1883;

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

void WIFIConnect() {
  Serial.print("Connecting to SSID: ");
  Serial.println(SSID);
  WiFi.begin(SSID, PASSWORD);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println();
  Serial.print("WiFi connected, IP address: ");
  Serial.println(WiFi.localIP());
}

void MQTT_Reconnect() {
  while (!client.connected()) {
    if (client.connect(MQTT_ID)) {
      Serial.println("Connected to MQTT Broker!");
    } else {
      Serial.print("Failed, rc=");
      Serial.print(client.state());
      Serial.println(" trying again in 5 seconds");
      delay(5000);
    }
  }
}

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

  WIFIConnect();
  client.setServer(MQTTServer, Port);
}

void loop() {
  if (!client.connected()) {
    MQTT_Reconnect();
  }
  client.loop();

  
  float humidity = dht.readHumidity();
  float temperature = dht.readTemperature();

  
  if (isnan(humidity) || isnan(temperature)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }

  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.print(" °C, Humidity: ");
  Serial.print(humidity);
  Serial.println(" %");

 
  String jsonData = "{";
  jsonData += "\"Nhiệt độ\": " + String(temperature) + ", ";
  jsonData += "\"Độ ẩm\": " + String(humidity);
  jsonData += "}";

  
  client.publish(MQTT_Topic, jsonData.c_str());

  delay(2000); 
}