#include <PubSubClient.h>
#include<WiFi.h>
#include "DHT.h"
#define DHTPIN 5
String data_send;
const char* mqtt_server = "broker.hivemq.com";
 
int status = WL_IDLE_STATUS;
WiFiClient wifiClient;
PubSubClient client(wifiClient);
 
#define DHTTYPE DHT22 
 
float tempC = 0.0;
float cToFRate = 1.8;
float cToF32 = 32;
float humidity = 0.0;
DHT dht(DHTPIN, DHTTYPE);

const char * MQTT_Topic = "21004196";

// Tạo ID ngẫu nhiên tại: https://www.guidgen.com/
const char * MQTT_ID = "22222";

void setup() {
  Serial.begin(115200);
  delay(10);
 
  WiFi.mode(WIFI_STA);
  WiFi.disconnect();
 
  delay(100);
  dht.begin();
  WIFIConnect();
  initMQTT();
}

void loop() {
  if(WiFi.status() != WL_CONNECTED){
    WIFIConnect();
  } else {
    if(!client.connected()){
      MQTT_Reconnect();
    } else {
      publishDHT22(); 
    }
  }
  client.loop();
  delay(2000);
}

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 initMQTT(){
  Serial.println("Initializing MQTT");
   
  randomSeed(micros());
  client.setServer(mqtt_server, 1883);
  MQTT_Reconnect();
}
 
void MQTT_Reconnect() {
  while (!client.connected()) {
    if (client.connect(MQTT_ID)) {
      Serial.print(MQTT_Topic);
      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 publishDHT22(){

    float h = dht.readHumidity();
    float t = dht.readTemperature();
    data_send = "{\"ND\":\"" + String(t) + "\",\"DA\":\"" + String(h) + "\"}";
    Serial.println(data_send);
    client.publish(MQTT_Topic, String(data_send).c_str()); 
}

float convertCtoF(float t){
  return ((t * cToFRate) + cToF32);
}