#include <Arduino.h>
#include <WiFi.h>
#include <WiFiClientSecure.h>
#include <PubSubClient.h>
#include "DHT.h"

// --- Kredensial Jaringan & MQTT ---
const char* ssid = "Wokwi-GUEST";
const char* password = "";

const char* mqtt_broker = "bb34e537503640d8be5c558a750405ce.s1.eu.hivemq.cloud";
const int mqtt_port = 8883;
const char* mqtt_username = "jaws123";
const char* mqtt_password = "Jaws1234";

// Topic diubah agar relevan dengan sensor DHT22
const char* topic_publish_dht = "esp32/dht22_sensor";

// --- Konfigurasi Sensor DHT22 ---
const int dht_pin = 19;
#define DHTTYPE DHT22
DHT dht(dht_pin, DHTTYPE);

// --- Pembuatan Instance ---
WiFiClientSecure wifiClient;
PubSubClient mqttClient(wifiClient);

// --- Variabel Timer Non-Blocking ---
unsigned long previous_time = 0;
unsigned long lastReconnectAttempt = 0;
const unsigned long PUBLISH_INTERVAL = 10000; // Konsisten: 10 detik

void setup() {
  Serial.begin(115200);
  
  // Inisialisasi Sensor DHT
  dht.begin();

  // Inisialisasi Wi-Fi
  Serial.print("Connecting to Wi-Fi");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nConnected to Wi-Fi");

  // Konfigurasi Klien Secure (Peringatan: Hindari setInsecure untuk tahap produksi)
  wifiClient.setInsecure(); 
  
  mqttClient.setServer(mqtt_broker, mqtt_port);
}

// Fungsi Reconnect Non-Blocking
boolean reconnect() {
  String clientId = "ESP32Client-" + String(random(0xffff), HEX);
  if (mqttClient.connect(clientId.c_str(), mqtt_username, mqtt_password)) {
    Serial.println("Connected to MQTT Broker.");
    return true;
  }
  Serial.print("Failed, rc=");
  Serial.println(mqttClient.state());
  return false;
}

void loop() {
  // 1. Manajamen Koneksi MQTT (Non-Blocking)
  if (!mqttClient.connected()) {
    unsigned long now = millis();
    if (now - lastReconnectAttempt > 5000) { // Coba koneksi ulang tiap 5 detik
      lastReconnectAttempt = now;
      Serial.println("Attempting MQTT connection...");
      if (reconnect()) {
        lastReconnectAttempt = 0;
      }
    }
    return; // Cegah pembacaan sensor jika MQTT terputus untuk menghemat resource
  }
  
  mqttClient.loop(); // Pertahankan aktivitas koneksi (Keep-Alive)

  // 2. Logika Pembacaan dan Publikasi (Non-Blocking)
  unsigned long now = millis();
  if (now - previous_time >= PUBLISH_INTERVAL) { 
    previous_time = now;

    // Membaca kelembaban dan suhu dalam Celcius
    float h = dht.readHumidity();
    float t = dht.readTemperature();

    // Validasi kebenaran data (mencegah NaN terkirim jika sensor gagal/kabel terputus)
    if (isnan(h) || isnan(t)) {
      Serial.println("Failed to read from DHT sensor!");
      return;
    }
    
    // Menyusun data dalam format JSON
    String payload = "{\"temperature\": " + String(t, 2) + ", \"humidity\": " + String(h, 2) + "}";
    
    // Publikasi data ke MQTT broker
    Serial.print("Publishing to ");
    Serial.print(topic_publish_dht);
    Serial.print(" | Payload: ");
    Serial.println(payload);
    
    mqttClient.publish(topic_publish_dht, payload.c_str());
  }
}