#include "DHT.h"
#include <WiFi.h>
extern "C"{
  #include "freertos/FreeRTOS.h"
  #include "freertos/timers.h"
}

#define ASYNC_TCP_SSL_ENABLED       true
#include <AsyncMqtt_Generic.h>

#define WIFI_SSID "Wokwi-GUEST"
#define WIFI_PASSWORD ""

#define MQTT_HOST IPAddress(192,168,1,1)
// #if ASYNC_TCP_SSL_ENABLED 
  
//    #define MQTT_SECURE     true 
    
//    const uint8_t MQTT_SERVER_FINGERPRINT[] = {0x7e, 0x36, 0x22, 0x01, 0xf9, 0x7e, 0x99, 0x2f, 0xc5, 0xdb, 0x3d, 0xbe, 0xac, 0x48, 0x67, 0x5b, 0x5d, 0x47, 0x94, 0xd2}; 
//    const char *PubTopic  = "async-mqtt/ESP32_SSL_Pub";               // Topic to publish 
    
//    #define MQTT_PORT       1883 
    
//  #else 
  
//    const char *PubTopic  = "async-mqtt/ESP32_Pub";                   // Topic to publish 
    
//    #define MQTT_PORT       1883 
    
//  #endif 
  
#define MQTT_PORT 1883 

#define MQTT_PUB_TEMP "esp32/dht/temperature"
#define MQTT_PUB_HUM "esp32/dht/humidity"

#define DHTPIN 4

#define DHTTYPE DHT22

DHT dht(DHTPIN, DHTTYPE);

float temp;
float hum;

AsyncMqttClient mqttClient;
TimerHandle_t mqttReconnectTimer; 
TimerHandle_t wifiReconnectTimer;

unsigned long previousMillis = 0;   // Stores last time temperature was published
const long interval = 10000; 


void connectToWifi(){
  Serial.println("Connecting to WiFi...");
  WiFi.begin(WIFI_SSID, WIFI_PASSWORD,6);
}

void connectToMqtt(){
  Serial.println("Connecting to Mqtt...");
  mqttClient.connect();
  Serial.println("Connected");
  // mqttClient.begin()
}

void WiFiEvent(WiFiEvent_t event){
  Serial.printf("[WiFi-event] event: %d\n", event);
  switch(event){
    case SYSTEM_EVENT_STA_GOT_IP:
      Serial.println("WiFi connected");
      Serial.println("IP address: ");
      Serial.println(WiFi.localIP());
      connectToMqtt();
      break;
    case SYSTEM_EVENT_STA_DISCONNECTED:
      Serial.println("WiFi lost connection");
      xTimerStop(mqttReconnectTimer, 0); // ensure we don't reconnect to MQTT while reconnecting to Wi-Fi
      xTimerStart(wifiReconnectTimer, 0);
      break;
  }
}

void onMqttConnect(bool sessionPresent){
  Serial.println("Connect to MQTT");
  Serial.println("Session present");
  Serial.println(sessionPresent);
}

void onMqttDisconnect (AsyncMqttClientDisconnectReason reason){
  Serial.println("Disconnect from Mqtt");
  if(WiFi.isConnected()){
    xTimerStart(mqttReconnectTimer, 0);
  }
}

void onMqttPublish(uint16_t packetId) {
  Serial.print("Publish acknowledged.");
  Serial.print("packetId: ");
  Serial.println(packetId);
}

void onMqttSubscribe(const uint16_t& packetId, const uint8_t& qos)
{
  Serial.println("Subscribe acknowledged.");
  Serial.print("  packetId: "); Serial.println(packetId);
  Serial.print("  qos: ");      Serial.println(qos);
}

void setup() {
  Serial.begin(115200);
  Serial.println();

  dht.begin();

  mqttReconnectTimer = xTimerCreate("mqttTimer", pdMS_TO_TICKS(2000), pdFALSE, (void*)0, reinterpret_cast<TimerCallbackFunction_t>(connectToMqtt));
  wifiReconnectTimer = xTimerCreate("wifiTimer", pdMS_TO_TICKS(2000), pdFALSE, (void*)0, reinterpret_cast<TimerCallbackFunction_t>(connectToWifi));

  WiFi.onEvent(WiFiEvent);

  mqttClient.onConnect(onMqttConnect);
  mqttClient.onDisconnect(onMqttDisconnect);

  mqttClient.onPublish(onMqttPublish);
  mqttClient.setServer(MQTT_HOST, MQTT_PORT);

  connectToWifi();

}

void loop() {
  unsigned long currentMillis = millis();

  if (currentMillis - previousMillis >= interval) {
    previousMillis = currentMillis;

    hum = dht.readHumidity();
    temp = dht.readTemperature();

    if(isnan(temp) || isnan(hum)){
      Serial.println(F("Failed to read from DHT sensor!"));
      return;
    }

    uint16_t packetIdSub = mqttClient.subscribe(MQTT_PUB_TEMP, 2); 
    Serial.print("Subscribing at QoS 2, packetId: "); Serial.println(packetIdSub); 

    uint16_t packetIdPub1 = mqttClient.publish(MQTT_PUB_TEMP,1,true,String(temp).c_str());
    Serial.printf("Publishing on topic %s at QoS 1, packetId: %i", MQTT_PUB_TEMP, packetIdPub1);
    Serial.printf("Message: %.2f \n", temp);

    uint16_t packetIdPub2 = mqttClient.publish(MQTT_PUB_HUM, 1, true, String(hum).c_str());                            
    Serial.printf("Publishing on topic %s at QoS 1, packetId %i: ", MQTT_PUB_HUM, packetIdPub2);
    Serial.printf("Message: %.2f \n", hum);
  }
}