public static BookComment ToEntity(this BookCommentModel model)
        {
            var entity = new BookComment()
            {
                Id          = model.Id,
                BookId      = model.BookId,
                UserId      = model.UserId,
                Comment     = model.Comment,
                Rating      = model.Rating,
                CreatedDate = model.CreatedDate
            };

            return(entity);
        }
        public static BookCommentModel ToModel(this BookComment entity)
        {
            var model = new BookCommentModel()
            {
                Id          = entity.Id,
                BookId      = entity.BookId,
                UserId      = entity.UserId,
                Comment     = entity.Comment,
                Rating      = entity.Rating.HasValue ? entity.Rating.Value : 0,
                CreatedDate = entity.CreatedDate
            };

            return(model);
        }