// MQTT Server use: broker.mqtt-dashboard.com

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


const int DHT_PIN = 15;
DHTesp dhtSensor;

const char* ssid = "Wokwi-GUEST";
const char* password = "";

//***Set server***
const char* mqttServer = "broker.mqtt-dashboard.com"; 
int port = 1883;

WiFiClient espClient;
PubSubClient client(espClient);

void wifiConnect() {
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println(" Connected!");
}

void mqttReconnect() {
  while(!client.connected()) {
    Serial.println("Attemping MQTT connection...");
    //***Change "123456789" by your student id***
    if(client.connect("20127404_20127442_20127204")) {
      Serial.println("connected");
    }
    else {
      Serial.println("try again in 5 seconds");
      delay(5000);
    }
  }
}

void setup() {
  Serial.begin(115200);
  dhtSensor.setup(DHT_PIN, DHTesp::DHT22);

  wifiConnect();
  client.setServer(mqttServer, port);
  client.setCallback(callback);
}

//MQTT Receiver
void callback(char* topic, byte* message, unsigned int length) {
  Serial.println(topic);
  String strMsg;
  for(int i=0; i<length; i++) {
    strMsg += (char)message[i];
  }
  Serial.println(strMsg);
  
}

char* convertStringToChar(String str)
{
  int n = str.length();
  char char_array[n + 1];
  strcpy(char_array, str.c_str());
  return char_array;
}

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

  TempAndHumidity data = dhtSensor.getTempAndHumidity();
  String temperature_str = String(data.temperature, 2);
  char* temperature_char = convertStringToChar(temperature_str);
  String humidity_str = String(data.humidity, 1);
  char* humidity_char = convertStringToChar(humidity_str);
  Serial.println(String(data.humidity, 1));
  client.publish("20127404_20127442_20127204/temperature/in", temperature_char);
  client.publish("20127404_20127442_20127204/humidity/in", humidity_char);
  delay(500); 
}