Save category meta as IDs

[helgatheviking]

In an ideal world , we'd save the category IDs. This will make it 100x easier to translate.

However, Woo core's category enhanced select saves SLUGS. that's why we have saved slugs now. 🙄

We could write our own custom JS for the enhanced select. If we start saving as IDs we'll technically need to run an update routine... though this is an unsupported plugin and since it doesn't update automagically we coudl require folks, re-save their meta.

wc_get_products() also doesn't yet support querying by term ID so the two things are kinda linked.

However, we can add support for querying by IDs like so:

function kia_query_by_ids( $wp_query_args, $query_vars ) {
	// Handle product categories by ID.
	if ( ! empty( $query_vars[ 'category_id' ] ) ) {
		unset( $wp_query_args['category_id'] );
		$wp_query_args['tax_query'][] = array(
			'taxonomy' => 'product_cat',
			'field'    => 'term_id',
			'terms'    => $query_vars['category_id'],
		);
	}

	// Handle product tags by ID.
	if ( ! empty( $query_vars['tag_id'] ) ) {
		unset( $wp_query_args['tag_id'] );
		$wp_query_args['tax_query'][] = array(
			'taxonomy' => 'product_tag',
			'field'    => 'term_id',
			'terms'    => $query_vars['tag_id'],
		);
	}

	return $wp_query_args;
}
add_filter( 'woocommerce_product_data_store_cpt_get_products_query', 'kia_query_by_ids', 10, 2 );