Additional fees woocommerce based on product input - php

Question

I've used this code to add additional fees to the woocommerce product https://sarkware.com/woocommerce-change-product-price-dynamically-while-adding-to-cart-without-using-plugins/
my function
function calculate_aditional_fees( $cart_object ) {
if( !WC()->session->__isset( "reload_checkout" ) ) {
$additional_price = get_option( 'additional_person_price' );
$additional_driver_price = get_option( 'additional_driver_price' );
foreach ( $cart_object->cart_contents as $key => $value ) {
if ( $additional_driver_price > 0 || $additional_price > 0 ) {
$additional_price *= $value['additional-persons'];
$additional_driver_price *= $value['additional-drivers'];
$cart_object->cart_contents[$key]['data']->price = floatval( $value['data']->price ) + $additional_driver_price + $additional_price;
}
}
}
}
The first problem was that all the extra fees ware added twice (when using the add to cart button). I've just hacked this by dividing additional charges by two.
The problem after that is that after clicking the make payment in the order form, the final price is changed - the're is one fourth of the additional charges added again.
Example. Original price 500, additional person costs 40 the user chooses to add 1 additional person.
The calculation when adding to cart is 40*1/2 (this is done twice for some reason)
after adding to cart is 540 which is ok.
But after making payment (payment method is bank/wire transfer) the confirmation shows 560 as the order price which is big problem obviously.
I would appreciate any help on this.
The fields for additional persons are added via a hook (basically as in the tutorial).
add_action( 'woocommerce_before_add_to_cart_button', 'add_form_before_booking_product' );
function add_form_before_booking_product() {
global $post;
if( function_exists('get_product') ){
$product = get_product( $post->ID );
if( $product->is_type( 'booking' ) ){
echo '<table class="variations booking__variations"><tbody>
<tr>
<td class="label"><label for="additional-persons">'. __( 'Additional persons' ) .'</label></td>
<td class="value">
<input type="number" name="additional-persons" value="0" min="0" max=10 required />
</td>
</tr>
</tbody>
</table>';
}
}
}
After Loads of searching I changed the hook to woocommerce_cart_calculate_fees
Removed the division. The problem here is that the calculation is ok, after payment also but in the cart table subtotal and total are wrong (the values aren't added).
I've tried to calculate this manually so the function looks
function calculate_aditional_fees( $cart_object ) {
if( !WC()->session->__isset( "reload_checkout" )) {
$additional_price = get_option( 'additional_person_price' );
$additional_driver_price = get_option( 'additional_driver_price' );
foreach ( $cart_object->cart_contents as $key => $value ) {
if ( $additional_driver_price > 0 || $additional_price > 0 ) {
$additional_price = get_option( 'additional_person_price' );
$additional_driver_price = get_option( 'additional_driver_price' );
$additional_price = floatval( $additional_price ) * intval( $value['additional-persons'] );
$additional_driver_price = floatval( $additional_driver_price ) * intval( $value['additional-drivers'] );
$sum =( $additional_driver_price + $additional_price ) * WC()->cart->cart_contents[$key]['quantity'];
$sum2 =( $additional_driver_price + $additional_price );
WC()->cart->cart_contents[$key]['data']->price = floatval( $value['data']->price ) + $sum2;
// $additional_sum = $sum / 1.23;
// $additional_tax = $sum-$additional_sum;
// if (!is_checkout()) {
// WC()->cart->cart_contents[$key]['line_total'] += $additional_sum;
// WC()->cart->cart_contents_total += $additional_sum;
// WC()->cart->subtotal += $sum;
// WC()->cart->subtotal_ex_tax += $additional_sum;
// WC()->cart->taxes[1] += $additional_tax;
// }
// WC()->cart->add_fee('Dodtkowe opcje',($additional_driver_price + $additional_price)*WC()->cart->cart_contents[$key]['quantity']);
}
}
}
}
add_action( 'woocommerce_cart_calculate_fees', 'calculate_aditional_fees');
When removing the comments the sum and subtotal are ok, but then after making payment the additional cost are added once again so Im back to the same problem.
This works but...
It add another line under the subtotal in cart page, the calculation are ok, not yet the solution I'm looking for (the customers don't see per product fees but as one total)
function calculate_aditional_fees( ) {
if( !WC()->session->__isset( "reload_checkout" )) {
$additional_price = get_option( 'additional_person_price' );
$additional_driver_price = get_option( 'additional_driver_price' );
$sum =0;
foreach ( WC()->cart->cart_contents as $key => $value ) {
if ( $additional_driver_price > 0 || $additional_price > 0 ) {
$additional_price = get_option( 'additional_person_price' );
$additional_driver_price = get_option( 'additional_driver_price' );
$additional_price = floatval( $additional_price ) * intval( $value['additional-persons'] );
$additional_driver_price = floatval( $additional_driver_price ) * intval( $value['additional-drivers'] );
$sum += ( $additional_driver_price + $additional_price ) * WC()->cart->cart_contents[$key]['quantity'];
}
}
WC()->cart->add_fee(__('Fee','woocommerce'),$sum);
}
}
add_action( 'woocommerce_cart_calculate_fees', 'calculate_aditional_fees');