WooCommerce Checkout - Validate User Role and Cart Contents

Question

I'm facing a challenge with WooCommerce's checkout process.

I use the "B2B for WooCommerce" plugin to differentiate between regular products and B2B product. Here's the scenario:

1 - A unregistered visitor adds products from the "Regular" category (available by default to unregistered visitors) to their cart.

2 - On the checkout page, the visitor decides to register as a B2B client (by form select field on the checkout page).

3 - The registration and checkout processes occur simultaneously on this single page.

I want to prevent the order from being placed if a user is registering as a B2B client and has "Regular" products in their cart. Since both actions (registration and checkout) happen at once, typical WooCommerce hooks aren't working as expected.

How can I validate the user role being registered and the cart contents during checkout process and prevent the order if the conditions are met? Or maybe there's a better, simpler way to do this?

I've tried a function to reset the cart and reload the page.

Edit:

User Role: Wwp_wholesaler

I've created two WooCommerce product categories: Normal and Wholesale. The "Normal" one is visible to all visitors. The "Wholesale" becomes visible to "Wwp_wholesaler" after they register with that role.

The name attribute of the select field is: "afreg_select_user_role". The value attributes for the options are "customer" for regular customers and "wwp_wholesaler" for wholesalers.

Answer 1

The following code will early stop the checkout process when a B to B customer is detected with regular items in cart. In that case, the regular items will be removed from cart throwing an error message, avoiding placing the order.

Note: The provided user role slug is wrong, as user role slugs doesn't have capitals.

The code:

add_action( 'woocommerce_checkout_create_order', 'process_checkout_creating_order',  10, 2  );
function process_checkout_creating_order( $order, $data ) {
    global $current_user;

    $targeted_field = 'afreg_select_user_role'; // Checkout field key to target
    $targeted_role  = 'wwp_wholesaler'; // User role slug (for B to B)
    $targeted_term  = 'Normal'; // Category term for Regular items

    // Targeting B to B user role only
    if( ( isset($data[$targeted_field]) && $data[$targeted_field] === $targeted_role ) 
    || in_array( $targeted_role, $current_user->roles ) ) {
        $cart = WC()->cart; //  Cart live object
        $item_keys_found = array(); // Initializing

        // Loop through cart items to search for "regular" items
        foreach ( $cart->get_cart() as $item_key => $item ) {
            if ( has_term( $targeted_term, 'product_cat', $item['product_id']) ) {
                $item_keys_found[] = $item_key;
            }
        }
        // If regular items are found
        if ( count($item_keys_found) > 0 ) {
            // Loop through regular item keys (and remove each)
            foreach ( $item_keys_found as $item_key ) {
                $cart->remove_cart_item( $item_key );
            }
            // Throw an error message, avoiding saving and processing the order
            throw new Exception( 
                sprintf( __('You are not allowed to purchase "Regular" items.'.
                ' %d "Regular" %s been removed from cart. %s', 'woocommerce'),
                    count($item_keys_found),
                    _n('item has', 'items have', count($item_keys_found), 'woocommerce'),
                    sprintf( '<a href="%s" class="button">%s</a>', get_permalink(wc_get_page_id('shop')), __('Continue shopping', 'woocommerce') )
            ) );
        }
    }
}

Code goes in functions.php file of your child theme (or in a plugin). Tested and work.