public Result <Book> Cancel(Guid bookId, bool isAdmin = false)
{
var book = _repository.Get().Include(x => x.BookUsers).FirstOrDefault(x => x.Id == bookId);
if (book == null)
{
throw new ShareBookException(ShareBookException.Error.NotFound);
}
if (!isAdmin && book.BookUsers != null && book.BookUsers.Count > 0)
{
throw new ShareBookException("Este livro já possui interessados");
}
book.Approved = false;
book.ChooseDate = null;
book.Canceled = true;
_repository.Update(book);
_booksEmailService.SendEmailBookCanceledToAdmins(book).Wait();
return(new Result <Book>(book));
}