public IEnumerable<Product> GetProductsNotInGroceries(IGroceryRepository repo)
{
List<Product> selectedProducts;
if (!repo.GetGroceries().Any()) {
selectedProducts = repo.GetProducts().ToList();
} else {
var groceries = repo.GetGroceries().Select(p => p.ProductId).ToArray();
var products = repo.GetProducts().Select(p => p.Id).ToArray();
var unselected = products.Except(groceries);
selectedProducts = repo.GetProducts().Where(p => unselected.Contains(p.Id)).ToList();
}
return selectedProducts;
}
