!7

cmodule FrontendUnloader > DynPrintLogAndEnabled {

  switchable double timeout = 60.0; // in seconds after last activity

  switchable double checkInterval = 10.0;

  switchable bool actuallyUnload;

  switchable bool verbose;

  transient bool firstCheck = true;

  transient volatile bool unloading;

  start {

    dm_registerAs_direct chatBotFrontendUnloader();

    dm_doEvery(1.0, checkInterval, r check);

  }

  void check enter {

    if (!enabled || dm_isBooting()) ret;

    // stayLoaded -> module ID. also has a null key!

    new MultiMap<Bool, S> mm;

    for (O mod : vmBus_queryAll chatBotFrontend()) {

      Bool b = cast dm_call(mod, 'shouldStayLoaded, timeout);

      mm.put(b, dm_moduleID(mod));

    }

    if (empty(mm)) ret;

    int nPlus = l(mm.get(true));

    int nMinus = l(mm.get(false));

    int nIndifferent = l(mm.get(null));

    if (verbose)

      printWithTime("Results for timeout " + timeout + "s: " + nPlus + " should stay loaded, "

        + nMinus + " can be unloaded, " + nIndifferent + " indifferent");

    if (actuallyUnload)

      if (firstCheck)

        firstCheck = false;

      else

        unloadModules(mm.get(false));

  }

  void unloadModules(LS modules) {

    if (empty(modules)) ret;

    temp dm_tempSetField(unloading := true);

    print("Unloading " + nModules(modules));

    for (S mod : modules) {

      print("  Unloading " + dm_moduleIDAndName(mod));

      dm_pcall(mod, 'deleteYourself);

    }

  }

  afterVisualize {

    addComponentInFront(buttons, dm_checkBox actuallyUnload());

  }

  // API

  bool isUnloading() { ret unloading; }

}