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

const char* WIFI_SSID = "Wokwi-GUEST";
const char* WIFI_PASSWORD = "";

const char* THINGSBOARD_SERVER = "thingsboard.cloud";
const char* ACCESS_TOKEN = "your_access_token"; 

WiFiClient espClient;
PubSubClient client(espClient);

#define DHT_PIN 32
#define DHT_TYPE DHT22
DHT dht(DHT_PIN, DHT_TYPE);

#define LED_PIN 2

void callback(char* topic, byte* payload, unsigned int length) {
  String topicStr = String(topic);
  String message;
  for (int i = 0; i < length; i++) {
    message += (char)payload[i];
  }

  Serial.print("Topic: "); Serial.println(topicStr);
  Serial.print("Message: "); Serial.println(message);

  if (topicStr.startsWith("v1/devices/me/rpc/request/")) {
    if (message.indexOf("true") > 0) {
      digitalWrite(LED_PIN, HIGH);
      Serial.println("LED ON (RPC)");
    } else {
      digitalWrite(LED_PIN, LOW);
      Serial.println("LED OFF (RPC)");
    }

    String responseTopic = topicStr;
    responseTopic.replace("request", "response");
    client.publish(responseTopic.c_str(), message.c_str());
  }
}

void setup() {
    Serial.begin(115200);
    pinMode(LED_PIN, OUTPUT);
    dht.begin();
    
    WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
    Serial.print("Đang kết nối WiFi");
    while (WiFi.status() != WL_CONNECTED) {
        delay(500);
        Serial.print(".");
    }
    Serial.println("\n Đã kết nối WiFi!");

    // Kết nối MQTT ThingsBoard
    client.setServer(THINGSBOARD_SERVER, 1883);
    client.setCallback(callback);

    while (!client.connected()) {
      if (client.connect("ESP32", ACCESS_TOKEN, NULL)) {
        Serial.println("Connected to ThingsBoard");
        client.subscribe("v1/devices/me/rpc/request/+");
      } else {
        Serial.print(".");
        delay(500);
      }
    }
}

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

    client.loop();

    float temperature = dht.readTemperature();
    float humidity = dht.readHumidity();
    
    Serial.printf("Temperature: %.2f°C, Humidity: %.2f%%\n", 
                    temperature, humidity);

    // Gửi dữ liệu lên ThingsBoard
    String payload = "{";
    payload += "\"temperature\":" + String(temperature) + ",";
    payload += "\"humidity\":" + String(humidity);
    payload += "}";

    Serial.print("Gửi dữ liệu: ");
    Serial.println(payload);

    client.publish("v1/devices/me/telemetry", payload.c_str());

    delay(5000);
}

// Hàm kết nối lại MQTT nếu bị mất kết nối
void reconnect() {
    while (!client.connected()) {
        Serial.print("Đang kết nối MQTT...");
        if (client.connect("ESP32_Client", ACCESS_TOKEN, "")) {
            Serial.println("Kết nối MQTT thành công!");
            client.subscribe("v1/devices/me/rpc/request/+");
        } else {
            Serial.print("Thất bại, mã lỗi: ");
            Serial.println(client.state());
            delay(2000);
        }
    }
}