Clear cart based on user role

Hi there,

I have setup a Trade/Wholesale category page on my shop, available only to a custom user role. While the trade user can still see the rest of the site (single products) they can only add Trade (bulk) products to their cart.

However, if they are not logged in, they can add single products to cart as a guest, but when they login as a Trade user those single products are still in their cart.

Is there a way to clear their cart when they log in? Ideally this would only target the Trade user role, and not clear the cart if a normal customer signs in.

Thanks for any help or suggestions!