private static boolean canStickActionsTogether(
     final PostprocessFormattingTask currentTask, final PostprocessFormattingTask nextTask) {
   // empty reformat markers can't sticked together with any action
   if (nextTask instanceof ReformatWithHeadingWhitespaceTask
       && nextTask.getStartOffset() == nextTask.getEndOffset()) return false;
   if (currentTask instanceof ReformatWithHeadingWhitespaceTask
       && currentTask.getStartOffset() == currentTask.getEndOffset()) {
     return false;
   }
   // reindent actions can't be sticked at all
   return !(currentTask instanceof ReindentTask);
 }
  private List<PostponedAction> normalizeAndReorderPostponedActions(
      final TreeSet<PostprocessFormattingTask> rangesToProcess, Document document) {
    final List<PostprocessFormattingTask> freeFormatingActions =
        new ArrayList<PostprocessFormattingTask>();
    final List<ReindentTask> indentActions = new ArrayList<ReindentTask>();

    PostprocessFormattingTask accumulatedTask = null;
    Iterator<PostprocessFormattingTask> iterator = rangesToProcess.iterator();
    while (iterator.hasNext()) {
      final PostprocessFormattingTask currentTask = iterator.next();
      if (accumulatedTask == null) {
        accumulatedTask = currentTask;
        iterator.remove();
      } else if (accumulatedTask.getStartOffset() > currentTask.getEndOffset()
          || accumulatedTask.getStartOffset() == currentTask.getEndOffset()
              && !canStickActionsTogether(accumulatedTask, currentTask)) {
        // action can be pushed
        if (accumulatedTask instanceof ReindentTask) {
          indentActions.add((ReindentTask) accumulatedTask);
        } else {
          freeFormatingActions.add(accumulatedTask);
        }

        accumulatedTask = currentTask;
        iterator.remove();
      } else if (accumulatedTask instanceof ReformatTask && currentTask instanceof ReindentTask) {
        // split accumulated reformat range into two
        if (accumulatedTask.getStartOffset() < currentTask.getStartOffset()) {
          final RangeMarker endOfRange =
              document.createRangeMarker(
                  accumulatedTask.getStartOffset(), currentTask.getStartOffset());
          // add heading reformat part
          rangesToProcess.add(new ReformatTask(endOfRange));
          // and manage heading whitespace because formatter does not edit it in previous action
          iterator = rangesToProcess.iterator();
          //noinspection StatementWithEmptyBody
          while (iterator.next().getRange() != currentTask.getRange()) ;
        }
        final RangeMarker rangeToProcess =
            document.createRangeMarker(currentTask.getEndOffset(), accumulatedTask.getEndOffset());
        freeFormatingActions.add(new ReformatWithHeadingWhitespaceTask(rangeToProcess));
        accumulatedTask = currentTask;
        iterator.remove();
      } else {
        if (!(accumulatedTask instanceof ReindentTask)) {
          iterator.remove();

          boolean withLeadingWhitespace =
              accumulatedTask instanceof ReformatWithHeadingWhitespaceTask;
          if (accumulatedTask instanceof ReformatTask
              && currentTask instanceof ReformatWithHeadingWhitespaceTask
              && accumulatedTask.getStartOffset() == currentTask.getStartOffset()) {
            withLeadingWhitespace = true;
          } else if (accumulatedTask instanceof ReformatWithHeadingWhitespaceTask
              && currentTask instanceof ReformatTask
              && accumulatedTask.getStartOffset() < currentTask.getStartOffset()) {
            withLeadingWhitespace = false;
          }
          int newStart = Math.min(accumulatedTask.getStartOffset(), currentTask.getStartOffset());
          int newEnd = Math.max(accumulatedTask.getEndOffset(), currentTask.getEndOffset());
          RangeMarker rangeMarker;

          if (accumulatedTask.getStartOffset() == newStart
              && accumulatedTask.getEndOffset() == newEnd) {
            rangeMarker = accumulatedTask.getRange();
          } else if (currentTask.getStartOffset() == newStart
              && currentTask.getEndOffset() == newEnd) {
            rangeMarker = currentTask.getRange();
          } else {
            rangeMarker = document.createRangeMarker(newStart, newEnd);
          }

          if (withLeadingWhitespace) {
            accumulatedTask = new ReformatWithHeadingWhitespaceTask(rangeMarker);
          } else {
            accumulatedTask = new ReformatTask(rangeMarker);
          }
        } else if (currentTask instanceof ReindentTask) {
          iterator.remove();
        } // TODO[ik]: need to be fixed to correctly process indent inside indent
      }
    }
    if (accumulatedTask != null) {
      if (accumulatedTask instanceof ReindentTask) {
        indentActions.add((ReindentTask) accumulatedTask);
      } else {
        freeFormatingActions.add(accumulatedTask);
      }
    }

    final List<PostponedAction> result = new ArrayList<PostponedAction>();
    Collections.reverse(freeFormatingActions);
    Collections.reverse(indentActions);

    if (!freeFormatingActions.isEmpty()) {
      FormatTextRanges ranges = new FormatTextRanges();
      for (PostprocessFormattingTask action : freeFormatingActions) {
        TextRange range = TextRange.create(action);
        ranges.add(range, action instanceof ReformatWithHeadingWhitespaceTask);
      }
      result.add(new ReformatRangesAction(ranges));
    }

    if (!indentActions.isEmpty()) {
      ReindentRangesAction reindentRangesAction = new ReindentRangesAction();
      for (ReindentTask action : indentActions) {
        reindentRangesAction.add(action.getRange(), action.getOldIndent());
      }
      result.add(reindentRangesAction);
    }

    return result;
  }