text: #include "wled.h"
  
  /*
   * Methods to handle saving and loading presets to/from the filesystem
   */
  
  bool applyPreset(byte index)
  {
    JsonDocument* doc = fileDoc;
    if (doc) {
      errorFlag = readObjectFromFileUsingId("/presets.json", index, doc) ? ERR_NONE : ERR_FS_PLOAD;
      JsonObject fdo = doc->as<JsonObject>();
      if (fdo["ps"] == index) fdo.remove("ps"); //remove load request for same presets to prevent recursive crash
      #ifdef WLED_DEBUG_FS
        serializeJson(*doc, Serial);
      #endif
      deserializeState(fdo);
    } else {
      DEBUGFS_PRINTLN(F("Make read buf"));
      DynamicJsonDocument fDoc(JSON_BUFFER_SIZE);
      errorFlag = readObjectFromFileUsingId("/presets.json", index, &fDoc) ? ERR_NONE : ERR_FS_PLOAD;
      JsonObject fdo = fDoc.as<JsonObject>();
      if (fdo["ps"] == index) fdo.remove("ps");
      #ifdef WLED_DEBUG_FS
        serializeJson(fDoc, Serial);
      #endif
      deserializeState(fdo);
    }
  
    if (!errorFlag) {
      currentPreset = index;
      isPreset = true;
      return true;
    }
    return false;
  }
  
  void savePreset(byte index, bool persist, const char* pname, JsonObject saveobj)
  {
    if (index == 0 || index > 250) return;
    bool docAlloc = (fileDoc != nullptr);
    JsonObject sObj = saveobj;
  
    if (!docAlloc) {
      DEBUGFS_PRINTLN(F("Allocating saving buffer"));
      DynamicJsonDocument lDoc(JSON_BUFFER_SIZE);
      sObj = lDoc.to<JsonObject>();
      if (pname) sObj["n"] = pname;
      DEBUGFS_PRINTLN(F("Save current state"));
      serializeState(sObj, true);
      currentPreset = index;
  
      writeObjectToFileUsingId("/presets.json", index, &lDoc);
    } else { //from JSON API
      DEBUGFS_PRINTLN(F("Reuse recv buffer"));
      sObj.remove(F("psave"));
      sObj.remove(F("v"));
  
      if (!sObj["o"]) {
        DEBUGFS_PRINTLN(F("Save current state"));
        serializeState(sObj, true, sObj["ib"], sObj["sb"]);
        currentPreset = index;
      }
      sObj.remove("o");
      sObj.remove("ib");
      sObj.remove("sb");
      sObj.remove(F("error"));
      sObj.remove(F("time"));
  
      writeObjectToFileUsingId("/presets.json", index, fileDoc);
    }
    presetsModifiedTime = now(); //unix time
    updateFSInfo();
  }
  
  void deletePreset(byte index) {
    StaticJsonDocument<24> empty;
    writeObjectToFileUsingId("/presets.json", index, &empty);
    presetsModifiedTime = now(); //unix time
    updateFSInfo();
  }