Pay 2% of Woo order total in myCRED points

/**
 * Point Payout
 * Pay 2% of the order total as points to buyer.
 * Will only pay if:
 * - Buyer is logged in
 * - Buyer pays using a non-manual payment gateway
 * - Buyer is not excluded from using myCRED
 * - myCRED is enabled
 *
 * @version 1.0
 */
add_action( 'woocommerce_payment_complete', 'mycred_pro_woo_purchase_reward' );
function mycred_pro_woo_purchase_reward( $order_id )
{
    if ( ! function_exists( 'mycred' ) ) return;

    $order = new WC_Order( $order_id );
    if ( $order->order_total == 0.00 || $order->order_total == 0 ) return;

    $point_type = 'mycred_default';
    $mycred     = mycred( $point_type );

    // Make sure buyer only get points once per order
    if ( $mycred->has_entry( 'shopping_reward', $order_id, $order->user_id ) ) return;

    // Add reward
    $mycred->add_creds(
        'shopping_reward',
        $order->user_id,
        ( $order->order_total * 0.02 ),
        'Reward for store purchase',
        $order_id,
        array( 'ref_type' => 'post' ),
        $point_type
    );
}