#include <WiFi.h>
#include <PubSubClient.h>
#include "DHTesp.h" //Thư viện cảm biến DHT11 cho esp32

DHTesp dht;

#define DHT_PIN 12
#define LED 3

//Thông số MQTT
const char *mqtt_broker = "broker.emqx.io";
const char *topic = "esp32/test";
const char *mqtt_username = "emqx";
const char *mqtt_password = "public";
const int mqtt_port = 1883;

WiFiClient espClient;
PubSubClient client(espClient);

void setup() {
    //Khởi tạo serial
    Serial.begin(115200);
    //Bật wifi chế độ sta, kết nối với mạng internet
    WiFi.begin("Wokwi-GUEST", "", 6);
    while (WiFi.status() != WL_CONNECTED) {
        delay(100);
        Serial.print(".");
    }
    Serial.println("Connected to the Wi-Fi network");
    dht.setup(DHT_PIN, DHTesp::DHT22);

    //Setup PinLED
    pinMode(LED, OUTPUT);
    digitalWrite(LED,LOW);;

    //Kết nối tới Broker của MQTT
    client.setServer(mqtt_broker, mqtt_port);
    client.setCallback(callback); // Gọi hàm đọc nội dung topic
    while (!client.connected()) {
        String client_id = "esp32-client-";
        client_id += String(WiFi.macAddress());
        Serial.printf("The client %s connects to the 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);
        }
    }
}

void readSensor_sendMQTT(){
    TempAndHumidity data = dht.getTempAndHumidity();
    // Publish
    client.publish(topic, String(data.temperature).c_str());
    //Đăng ký topic
    client.subscribe(topic);
    delay(100);
}

void callback(char *topic, byte *payload, unsigned int length) {
    //In nội dung của topic
    Serial.print("Message arrived in topic: ");
    Serial.println(topic);
    Serial.print("recived:");
    char *buf = (char*)malloc(20*sizeof(char));
    for (int i = 0; i < length; i++) {
        buf[i]=(char)payload[i];
        Serial.print(buf[i]);
    }
    Serial.println("\n-----------------------");
    if(strcmp(buf,"LED_ON")){
      digitalWrite(LED, HIGH);
    }else if(strcmp(buf,"LED_OFF")){
      digitalWrite(LED, LOW);
    }
    free(buf);
}

void loop() {
    client.loop();
    readSensor_sendMQTT();
    delay(1000);
}