#include <WiFi.h>
#include "PubSubClient.h"
#include "DHTesp.h"
#include <ArduinoJson.h>

const int DHT_PIN = 15;
DHTesp dhtSensor;

const char * MQTTServer = "broker.hivemq.com";
const char * MQTT_Topic = "DHT22-21004250";

// Tạo ID ngẫu nhiên tại: https://www.guidgen.com/
const char * MQTT_ID = "unique_id";  // Điền ID ngẫu nhiên ở đây
int Port = 1883;

WiFiClient espClient;
PubSubClient client(espClient);

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

void MQTT_Reconnect() {
  while (!client.connected()) {
    if (client.connect(MQTT_ID)) {
      Serial.print("MQTT Topic: ");
      Serial.print(MQTT_Topic);
      Serial.print(" connected");
      client.subscribe(MQTT_Topic);
      Serial.println("");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}

void callback(char* topic, byte* message, unsigned int length) {
  Serial.print("Message arrived on topic: ");
  Serial.println(topic);
  Serial.print("Message: ");
  String stMessage;

  for (int i = 0; i < length; i++) {
    Serial.print((char)message[i]);
    stMessage += (char)message[i];
  }
  Serial.println();
}

void setup() {
  Serial.begin(115200);
  WIFIConnect();
  client.setServer(MQTTServer, Port);
  client.setCallback(callback);
  dhtSensor.setup(DHT_PIN, DHTesp::DHT22);
}

void loop() {
  TempAndHumidity data = dhtSensor.getTempAndHumidity();
  if (isnan(data.temperature) || isnan(data.humidity)) {
    Serial.println("Failed to read from DHT sensor!");
  } else {
    Serial.println("Nhiệt độ: " + String(data.temperature, 2) + "°C");
    Serial.println("Độ ẩm: " + String(data.humidity, 1) + "%");

    char jsonBuffer[128];
    StaticJsonDocument<128> jsonDoc;
    jsonDoc["temperature"] = data.temperature;
    jsonDoc["humidity"] = data.humidity;
    serializeJson(jsonDoc, jsonBuffer);

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

    client.publish(MQTT_Topic, jsonBuffer);
    client.loop();
  }

  delay(2000); // Đọc dữ liệu mỗi 2 giây
}