Woocommerce: calculation of the discount for several items of the same product? [duplicate]

Question

I would like to change the code below to calculate the discount for 3 different product id's. If the customer buys 3 items of one product id, he will receive a 15% discount on everything, and if he buys 6 items, he will receive a 20% discount.

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

    // Specific tag
    $specific_tag = array( 'ashwagandha' );

    // Discount
    $discount = 20;
    
    // Min quantity
    $minimun_quantity = 6;

    /* END SETTINGS */
    
    // Counter
    $current_quantity = 0;

    // Loop though each cart item
    foreach ( $cart->get_cart() as $cart_item ) {
        // Get product id
        $product_id = $cart_item['product_id'];

        // Has certain tag     
        if ( has_term( $specific_tag, 'product_tag', $product_id ) ) {
            // Quantity
            $product_quantity = $cart_item['quantity'];

            // Add to total
            $current_quantity += $product_quantity;
        }
    }
// Greater than or equal to
    if ( $current_quantity >= $minimun_quantity ) {          
        // Add fee
        $cart->add_fee( __( 'Rabat', 'woocommerce' ), -$discount, false );      
    }
}
add_action( 'woocommerce_cart_calculate_fees', 'action_woocommerce_cart_calculate_fees', 10, 1 );