Add a quick buy now checkout button into single product page and shop loop item - Woocommerce

add-a-quick-buy-now-checkout-button-into-single-product-page-and-shop-loop-item-woocommerce.php

<?php

/*
 * Add a quick buy now checkout button in woocommerce into single product page and shop loop item
 */

add_action( 'woocommerce_after_shop_loop_item', 'add_custom_addtocart_and_checkout', 10 );
add_action( 'woocommerce_after_add_to_cart_button', 'add_custom_addtocart_and_checkout' );
function add_custom_addtocart_and_checkout() {
    global $product;

    $addtocart_url = wc_get_checkout_url().'?add-to-cart='.$product->get_id();
    $button_class  = 'single_add_to_cart_button button py-2';
    $button_text   = __("Paga ora", "woocommerce");

	if ( ! $product->is_purchasable() || ! $product->is_in_stock() ) {
		return;
	}
	
    if( $product->is_type( 'simple' )) :
    ?>
    <script>
    jQuery(function($) {
        var url    = '<?php echo $addtocart_url; ?>',
            qty    = 'input.qty',
            button = 'single_add_to_cart_button button py-2';

        // On input/change quantity event
        $(qty).on('input change', function() {
            $(button).attr('href', url + '&quantity=' + $(this).val() );
        });
    });
    </script>
    <?php

    elseif( $product->is_type( 'variable' ) ) : 

    $addtocart_url = wc_get_checkout_url().'?add-to-cart=';
    ?>
    <script>
    jQuery(function($) {
        var url    = '<?php echo $addtocart_url; ?>',
            vid    = 'input[name="variation_id"]',
            pid    = 'input[name="product_id"]',
            qty    = 'input.qty',
            button = 'single_add_to_cart_button button py-2';

        // Once DOM is loaded
        setTimeout( function(){
            if( $(vid).val() != '' ){
                $(button).attr('href', url + $(vid).val() + '&quantity=' + $(qty).val() );
            }
        }, 300 );

        // On input/change quantity event
        $(qty).on('input change', function() {
            if( $(vid).val() != '' ){
                $(button).attr('href', url + $(vid).val() + '&quantity=' + $(this).val() );
            }
        });

        // On select attribute field change event
        $('.variations_form').on('change blur', 'table.variations select', function() {
            if( $(vid).val() != '' ){
                $(button).attr('href', url + $(vid).val() + '&quantity=' + $(qty).val() );
            }
        });
    });
    </script>
    <?php
    endif;
    echo '<a style="display: flex !important; gap: 20px; justify-content: center; align-items: center; margin-top: 20px" href="'.$addtocart_url.'" class="'.$button_class.'"><i class="las la-credit-card la-lg d-none d-sm-inline"></i>'.$button_text.'</a>';
}