如何在购物车页面项目上添加自定义折扣？

Question

如果产品数量和数量大于1，我需要为每个产品增加$ 5折扣。这是我的代码。当我先在购物车中添加第二个项目时，它工作正常。但是，如果购物车中只有1个产品并且数量是2，则折扣不应适用于第一个数量，而应适用于第二个数量。

add_filter( 'woocommerce_before_calculate_totals', 'discount_on_cart_item', 10, 1 );
function discount_on_cart_item( $cart_object ) {

    if ( is_admin() && ! defined( 'DOING_AJAX' ) )
        return;


    $count = 0;
    $discount = 5; 
    $discount_appl = false;
    //$count = WC()->cart->get_cart_contents_count();


    foreach ( $cart_object->get_cart() as $cart_item ) {
        $count++;

        //echo $cart_item['quantity'];

        if( ($count == 1 && $cart_item['quantity'] > 1 ) || ($count > 1)){
            $price = $cart_item['data']->get_price(); // product price
            //$discounted_price = $price - ($price * $discount); // calculation

            $discounted_price = $price - $discount; // calculation

            // Set the new price
            $cart_item['data']->set_price( $discounted_price );
           // break; // stop the loop
           $discount_appl = true;
        } 

    }

     if ( $discount_appl && is_cart())
        wc_add_notice( __( 'A quantity discount has been applied', 'my_theme_slug' ), 'success' ); 
}