WooCommerce minimum order fee for products in specific category

Question

I want to add a fee in my woocommerce store for orders under a specific amount (value, not quantity).

I am using " WooCommerce dynamic minimum order amount based fee " answer code that works perfectly.

Now I am trying to change this functionand to apply it only to items from a specific product category. Basically, I have to sum the value of all the products in cart that matches the specific category and use this value for fee calculation.

How can I reach this goal?

Answer 1

The following revisited code will handle specific defined product categories. You will have to define:

• Your specific product categories in the 1st function.
• The minimal order amount in the 2nd and 3rd functions.

The code:

// Get the cart items subtotal amount from specific product categories
function get_specific_cart_items_total( $cart ) {
    $categories   = array('t-shirts'); // <=== Define your product categories
    $items_amount = 0; // Initializing

    // Loop through cart items
    foreach( $cart->get_cart() as $item ) {
        if( has_term( $categories, 'product_cat', $item['product_id'] ) ) {
            $items_amount += $item['line_subtotal'];
        }
    }
    return $items_amount;
}

// Add a custom fee (displaying a notice in cart page)
add_action( 'woocommerce_cart_calculate_fees', 'add_custom_surcharge', 10, 1 );
function add_custom_surcharge( $cart ) {
    if ( is_admin() && ! defined( 'DOING_AJAX' ) )
        return;

    if ( did_action( 'woocommerce_cart_calculate_fees' ) >= 2 )
        return;

    $min_price     = 200; // The minimal cart amount

    $current_price = get_specific_cart_items_total( $cart );
    $custom_fee    = $min_price - $current_price;

    if ( $custom_fee > 0 ) {
        $cart->add_fee( __('Minimum Order Adjustment'), $custom_fee, true );

        // NOTICE ONLY IN CART PAGE
        if( is_cart() ){
            wc_print_notice( get_custom_fee_message( $min_price, $current_price ), 'error' );
        }
    }
}

// Displaying the notice on checkout page
add_action( 'woocommerce_before_checkout_form', 'custom_surcharge_message', 10 );
function custom_surcharge_message(  ) {
    $min_price     = 200; // The minimal cart amount

    $cart          = WC()->cart;
    $current_price = get_specific_cart_items_total( $cart );
    $custom_fee    = $min_price - $current_price;

    // NOTICE ONLY IN CHECKOUT PAGE
    if ( $custom_fee > 0 ) {
        wc_print_notice( get_custom_fee_message( $min_price, $current_price ), 'error' );
    }
}

// The fee notice message
function get_custom_fee_message( $min_price, $current_price ) {
    return sprintf(
        __('We have a minimum %s per order from specific categories. As your current order is only %s, an additional fee will be applied.', 'woocommerce'),
        wc_price( $min_price ),
        wc_price( $current_price )
    );
}

Code goes in functions.php file of your active child theme (or active theme) . Tested and works.

---

Option: To handle parent product categories too, add the following additional function:

// Custom conditional function that handle parent product categories too
function has_product_categories( $categories, $product_id = 0 ) {
    $parent_term_ids = $categories_ids = array(); // Initializing
    $taxonomy        = 'product_cat';
    $product_id      = $product_id == 0 ? get_the_id() : $product_id;

    if( is_string( $categories ) ) {
        $categories = (array) $categories; // Convert string to array
    }

    // Convert categories term names and slugs to categories term ids
    foreach ( $categories as $category ){
        $result = (array) term_exists( $category, $taxonomy );
        if ( ! empty( $result ) ) {
            $categories_ids[] = reset($result);
        }
    }

    // Loop through the current product category terms to get only parent main category term
    foreach( get_the_terms( $product_id, $taxonomy ) as $term ){
        if( $term->parent > 0 ){
            $parent_term_ids[] = $term->parent; // Set the parent product category
            $parent_term_ids[] = $term->term_id; // (and the child)
        } else {
            $parent_term_ids[] = $term->term_id; // It is the Main category term and we set it.
        }
    }
    return array_intersect( $categories_ids, array_unique($parent_term_ids) ) ? true : false;
}

And replace in the first function this line:

if( has_term( $categories, 'product_cat', $item['product_id'] ) ) {

by this:

if( has_product_categories( $categories, $item['product_id'] ) ) {