PubSubClient mqtt_client(wifi);
long mqtt_last_reconnect_attempt = 0;

void mqtt_callback(char* topic, byte* payload, unsigned int length) {
  payload[length] = '\0';
  for (int i=0; i<NUM_EFFECTS; i++) {
    EffectEntry* e = &effects[i];
    if (strcmp(e->name, (char*)payload)==0) {
      //Serial.printf("Effect found in mqtt_callback: %p\n", (void *)&e->effect);
      current_effect = e->effect;
      clear();
      return;
    }
  }
}

boolean mqtt_connect() {
  char client_id[30];
  snprintf(client_id, 30, HOSTNAME, ESP.getChipId());
  LOG("MQTT * Connecting to MQTT server with client id "); LOGln(client_id);
  if (mqtt_client.connect(client_id, MQTT_USER, MQTT_PASS)) {
    LOGln("MQTT * Connected.");
    mqtt_client.subscribe(MQTT_TOPIC_MODE);
    mqtt_client.publish(MQTT_TOPIC_STATUS, "ONLINE");
  }
  return mqtt_client.connected();
}

void mqtt_setup() {
  mqtt_client.setServer(MQTT_SERVER, MQTT_PORT);
  mqtt_client.setCallback(mqtt_callback);
  mqtt_last_reconnect_attempt = 0;
}

void mqtt_loop() {
  if (!mqtt_client.connected()) {
    long now = millis();
    if (now - mqtt_last_reconnect_attempt > 5000) {
      mqtt_last_reconnect_attempt = now;
      if (mqtt_connect()) {
        mqtt_last_reconnect_attempt = 0;
      }
    }
  } else {
    mqtt_client.loop();
  }
}