package useCases

import (
	"RenewCMS/internal/domain/user"
	"errors"
)

type uploaderNames struct {
	userRepository user.Repository
	names          map[uint32]string
}

func newUploaderNames(userRepository user.Repository) *uploaderNames {
	return &uploaderNames{userRepository: userRepository, names: map[uint32]string{}}
}

func (u *uploaderNames) nameOf(userId uint32) (string, error) {
	if userId == 0 {
		return "", nil
	}
	if name, ok := u.names[userId]; ok {
		return name, nil
	}

	uploader, err := u.userRepository.Get(userId)
	if errors.Is(err, user.ErrUserNotFound) {
		u.names[userId] = ""
		return "", nil
	}
	if err != nil {
		return "", err
	}

	name := uploader.DisplayName
	if name == "" {
		name = uploader.Username
	}
	u.names[userId] = name
	return name, nil
}