// RetrieveLocation retrieves a location.
func RetrieveLocation(c *gin.Context) (model.Location, bool, int64, int, error) {
	var location model.Location
	var currentUserId int64
	isAuthor := false
	id := c.Params.ByName("id")
	if db.ORM.First(&location, "id = ?", id).RecordNotFound() {
		return location, isAuthor, currentUserId, http.StatusNotFound, errors.New("Location is not found.")
	}
	currentUser, err := userService.CurrentUser(c)
	if err == nil {
		currentUserId = currentUser.Id
		isAuthor = currentUser.Id == location.UserId
	}
	assignRelatedUser(&location)
	var commentList model.CommentList
	comments, currentPage, hasPrev, hasNext, _ := commentService.RetrieveComments(location)
	commentList.Comments = comments
	commentService.SetCommentPageMeta(&commentList, currentPage, hasPrev, hasNext, location.CommentCount)
	location.CommentList = commentList
	var likingList model.LikingList
	likings, currentPage, hasPrev, hasNext, _ := likingRetriever.RetrieveLikings(location)
	likingList.Likings = likings
	currentUserlikedCount := db.ORM.Model(&location).Where("id =?", currentUserId).Association("Likings").Count()
	log.Debugf("Current user like count : %d", currentUserlikedCount)
	likingMeta.SetLikingPageMeta(&likingList, currentPage, hasPrev, hasNext, location.LikingCount, currentUserlikedCount)
	location.LikingList = likingList
	return location, isAuthor, currentUserId, http.StatusOK, nil
}

// UpdateLocationCommentCount updates location's comment count.
func UpdateLocationCommentCount(location *model.Location) (int, error) {
	location.CommentCount = db.ORM.Model(location).Association("Comments").Count()
	if db.ORM.Save(location).Error != nil {
		return http.StatusInternalServerError, errors.New("Location comment's count is not updated.")
	}
	return http.StatusOK, nil
}

// assignRelatedUser assign related user to the location.
func assignRelatedUser(location *model.Location) {
	var tempUser model.User
	if db.ORM.Model(&location).Select(config.UserPublicFields).Related(&tempUser).RecordNotFound() {
		log.Warn("user is not found.")
	}
	location.Author = model.PublicUser{User: &tempUser}
}

// UpdateLocation updates a location.
func UpdateLocation(c *gin.Context) (model.Location, int, error) {
	var location model.Location
	var form LocationForm
	id := c.Params.ByName("id")
	c.BindWith(&form, binding.Form)
	if db.ORM.First(&location, id).RecordNotFound() {
		return location, http.StatusNotFound, errors.New("Location is not found.")
	}
	status, err := userPermission.CurrentUserIdentical(c, location.UserId)
	if err != nil {
		return location, status, err
	}
	location.Name = form.Name
	location.Address = form.Address
	location.Latitude = form.Latitude
	location.Longitude = form.Longitude
	location.Url = form.Url
	location.Content = form.Content
	if db.ORM.Save(&location).Error != nil {
		return location, http.StatusBadRequest, errors.New("Location is not updated.")
	}
	return location, http.StatusOK, nil
}