Add extra charge on shipping rate for each KG weight on cart by zone

Add extra charge on shipping rate for each KG weight on cart by zone.php

<?php
/**
 * Add extra charge on shipping rate for each KG weight on cart based by zone
 */

add_filter( 'woocommerce_package_rates', 'custom_delivery_flat_rate_cost_calculation_by_zone', 10, 2 );
function custom_delivery_flat_rate_cost_calculation_by_zone( $rates, $package )
{
    // The total cart items  weight
    $cart_weight = WC()->cart->get_cart_contents_weight();
	
	// Shipping zone
    $shipping_zone = wc_get_shipping_zone( $package );
    
    // Get zone ID
    $zone_id = $shipping_zone->get_id();
	
    foreach($rates as $rate_key => $rate_values){
        $method_id = $rate_values->method_id;
        $rate_id = $rate_values->id;
        if ($zone_id === 2 && 'wbs' === $method_id && $cart_weight > 100) { // Se lo slug di spedizione è uguale a, e il peso è maggiore di 500
            ##  SHIPPING COSTS AND TAXES CALCULATIONS ##
	for( $i = 200; $i <= $cart_weight; $i += 100 ){
            $rates[$rate_id]->cost += 15.49;
	}
            
        }
	    return $rates;
    }
}