Plugin to calculate My Custom Shipping Cost

my-custom-shipping-cost.php

<?php
/*
	Plugin Name: My Custom Shipping
	Description: Plugin to calculate My Custom Shipping Cost
  	Version: 1.0.0
	Author: WooForce
	Author URI: http://www.wooforce.com
*/

function my_custom_shipping_init() {
    class my_custom_shipping_method extends WC_Shipping_Method {
        
        public function __construct() {
            $this->id = 'my_custom_shipping';
            $this->method_title = __('My Custom Shipping', 'my-custom-shipping');
            $this->enabled = 'yes';
            $this->title = __('My Custom Shipping', 'my-custom-shipping');
            $this->method_description = __('Plugin to calculate My Custom Shipping Cost', 'my-custom-shipping');
        }
        
        function calculate_shipping( $package = array() ) {
            $shipping_cost = 0;
            $destination_country = $package['destination']['country'];
            switch($destination_country){
                case 'US': $shipping_cost = 5; break;
                case 'CA': $shipping_cost = 7; break;
            }

            $this->add_rate(array('id'        => 'my_custom_shipping',
                                            'label'     => 'Shipping Cost',
                                            'cost'      => $shipping_cost,
                                            'taxes'     => '',
                                            'calc_tax'  => 'per_order'));
        }						
    } 
}
add_action( 'woocommerce_shipping_init', 'my_custom_shipping_init' );

function my_custom_shipping_method( $methods )	{
    $methods[] = 'my_custom_shipping_method';
    return $methods;
}
add_filter( 'woocommerce_shipping_methods', 'my_custom_shipping_method' );