Add text by category and by user role

Yes that is possible, but this is quite a complex conditional. Also note that a product can have multiple categories and an order can have multiple products, so you will always need to loop through the product list of the order.

Here’s how you can find the user role of a customer:

if ( $user = $order->get_user() ) {
	$allowed_customer_roles = array( 'wholesale_customer', 'customer' );
	foreach ( $allowed_customer_roles as $customer_role ) {
		if ( in_array( $customer_role, (array) $user->roles ) ) {
			# we have a matching role
		}
	}
}

and here’s an example of how to create an array that holds all the categories of products in an order:

$order_cats = array();
foreach ($order->get_items() as $item_id => $item) {
    $terms = get_the_terms( $item['product_id'], 'product_cat' );
    if (empty($terms)) {
        continue;
    }
    foreach ($terms as $key => $term) {
        $order_cats[$term->term_id] = $term->name;
    }
}

Using these snippets you can print a text using one of the action hooks in the template.

Fortunately in my ecommerce products can have only 1 category and the cart is “limited to 1 product only” if a product of the “eventi” category is added (and automatically deletes other products if there were)
Known this, could you suggest me a code that does what I need?
Many thanks in advance

The above code examples will deal with that regardless of whether there is 1 or more product in the cart and whether the products have 1 or more categories. If you need more help with this, I suggest hiring a developer, this is quite advanced stuff.

thanks very much, I knew it wasn’t so simple…
Another question: I have this code you wrote me some days ago, this code adds a text in the invoice pdfs if the tax calculation equals to zero:

add_action( ‘wpo_wcpdf_after_order_details’, ‘wpo_wcpdf_tax_exempt’, 10, 2 );
function wpo_wcpdf_tax_exempt( $document_type, $order ) {
// only in financial documents
if ( !in_array( $document_type, array(‘invoice’, ‘proforma’, ‘credit-note’) ) ) {
return;
}

// check if any tax was charged
if ( $order->get_total_tax() == 0 && $order->get_total() > 0 ) {
?>
<div class=”tax-free”>
TEXT TEXT TEXT TEXT
</div>
<?php
}
}

what can I do to make the code do the same thing but by selecting the type of tax and not whit the calculation, I better explain:
if “zero tax” is selected -> html text 1
if “reduced tax” i selected -> html text 2
Thaanks again