#include <PubSubClient.h>
#include <WiFi.h>
#include <LiquidCrystal_I2C.h>
#include"DHT.h"
#define DHT_TYPE DHT22
#define DHT_PIN 27

LiquidCrystal_I2C lcd(0x27, 16, 2);
DHT dht(DHT_PIN, DHT_TYPE);

// WIFI config
const char* ssid = "Wokwi-GUEST";
const char* password = "";
WiFiClient wifiClient;
// MQTT client config
const char* mqttServer = "broker.hivemq.com";
const int mqttPort = 1883;
const char* mqttUser = "";
const char* mqttPassword = "";
const char* topic_pub = "ITKPS/Lab/6621601034/weather";
PubSubClient mqttClient(wifiClient);
// some variables buffer
String publishMessage;


void setup_wifi() {
 // Start by connecting to a WiFi network
 Serial.println();
 Serial.print("Connecting to ");
 Serial.println(ssid);
 WiFi.begin(ssid, password);
 while (WiFi.status() != WL_CONNECTED) {
  delay(500);
  Serial.print(".");
 }
 Serial.println();
 Serial.print("WiFi connected on ");
 Serial.print("IP address: ");
 Serial.print(WiFi.localIP());
 Serial.print(" MAC address: ");
 Serial.println(WiFi.macAddress());
 }

void reconnectMQTT() {
 // Loop until we're reconnected
 char mqttinfo[80];
 char clientId[100] = "\0";
 snprintf (mqttinfo, 75, "Attempting MQTT connection at %s:%d (%s/%s)...", mqttServer, mqttPort, mqttUser, mqttPassword);
 while (!mqttClient.connected()) {
  Serial.println(mqttinfo);
  sprintf(clientId, "ESP32Client-%04X", random(0xffff));
  if (mqttClient.connect(clientId)) {
   Serial.println("...MQTT Broker connected...");
   // subscribe here after connected
   // ในตัวอย่างของฝั่งส่ง ไม่มีการ subscribe topic ใด
  } else {
    Serial.print("failed, rc=");
    Serial.print(mqttClient.state());
    Serial.println(" try again in 5 seconds");
    // Wait 5 seconds before retrying
    delay(5000);
  }
 }
}
void setup() {
  Serial.begin(115200);
  setup_wifi();
  mqttClient.setServer(mqttServer, mqttPort);
  Serial.println("DHT test");
  dht.begin();
}

void loop() {
 if (!mqttClient.connected()) {
   reconnectMQTT();
  }
 mqttClient.loop();
 mqttClient.publish(topic_pub, publishMessage.c_str());
 Serial.println(publishMessage);
 delay(2000); // this speeds up the simulation
 float temperature = dht.readTemperature();
 float humidity = dht.readHumidity();
 if(isnan(temperature)||isnan(humidity)){
  Serial.println("Failed to read data from DHT sensor!");
  return;
 }

 char tempString[8];
 char humString[8];
 dtostrf(temperature, 1, 2, tempString);
 dtostrf(humidity, 1, 2, humString);

 publishMessage = String("{\"temperature\":") + tempString + ",\"humidity\":" + humString + "}";

  mqttClient.publish(topic_pub, publishMessage.c_str());
  Serial.println("Published: " + publishMessage);
  Serial.print("Humidity: ");
  Serial.print(humidity);
  Serial.print("% Temperature: ");
  Serial.print(temperature);
  Serial.println("°C");
  
}