sclass SystemStatus extends Module {
  JComponent visualize() {
    ret jSection("SYSTEM STATUS", makeBold(fontSize(25, jCenteredLiveValueLabel(systemStatus))));
  }
}

// changes the icon of all error-having modules' frames to a little flash icon
sclass ErrorIcon extends Module {
  void update {
    for (Module m : onModules()) {
      O error = m.getError();
      if (error != null)
        internalFrameIcon(m.vis, #1101276);
    }
  }
}

sclass LastErrors extends StaticModule_CalculatedList {
  L<PersistableThrowable> errors = synchroList();
  int errorsToKeep = 10;
  
  void addError(Throwable e) {
    if (e == null) ret;
    addToListWithMaxSize(errors, persistableThrowable(e), errorsToKeep);
    change();
  }
  
  L<S> calc() {
    ret allToString(cloneList(errors));
  }
}

sclass Debug_PrintChangedModules extends Module {
  IConceptIndex idx = new IConceptIndex {
    public void update(Concept c) {
      print("Change in concept " + c);
    }
    public void remove(Concept c) {}
  };
  
  void start() {
    addConceptIndex(idx);
  }
  
  void cleanMeUp {
    removeConceptIndex(idx);
  }
}