Using external product database directly (not importing)

Our existing shop has several integrations to suppliers, pos, packing systems etc, so we will want to keep the existing admin backend, only using woocommerce as a mobile-enabled responsive frontend, not administering the products from within wp/woo.

Is it possible to, instead of importing the products from old into woo regularly, to make woo to use the old database directly?

I’d imagine there could be a single php-module with functions like

get_product_by_id()
get_products_by_category()
get_product_category_by_id()
get_product_categories()  

which could be overwritten to get the data from the external database instead of the wp_posts and wp_postmeta tables.

Or am I mistaken?