TIL(20240716) [트렐로프로젝트- 카드순서이동 구현]

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@Transactional
  public void moveCardToPosition(Long cardId, int newPosition, Long userId) {
    User user = userRepository.findById(userId).orElseThrow(()-> new CustomException(ErrorEnum.USER_NOT_AUTHENTICATED));
    Card card = findCardById(cardId);
    card.checkUser(user);
    Columns column = card.getColumns();
    int currentPosition = card.getPosition();

    List<Card> cards = cardRepository.findByColumnIdOrderByPositionAsc(column.getId());

    if (newPosition < 0 || newPosition >= cards.size()) {
      throw new CustomException(ErrorEnum.WRONG_POSITION_NUMBER);
    }

    if(currentPosition < newPosition) { // current 3  newPosition 4
      for(Card c : cards) { // 4 , 5
        if (c.getPosition() > currentPosition && c.getPosition() <= newPosition) {
          c.setPosition(c.getPosition() - 1);
          cardRepository.save(c);
        }
      }
    } else {
      for(Card c : cards) {
        if(c.getPosition() >= newPosition && c.getPosition() < currentPosition) {
          c.setPosition(c.getPosition() + 1);
          cardRepository.save(c);
        }
      }
    }
    updateCardPosition(cardId, newPosition);
    reorderCards(column.getId());
  }

순서이동 기능 코드 풀이 필요