Tab mit Anfrageformular auf Produktseite

/* Anfrageformular im Tab auf Produktseite */
add_filter( 'woocommerce_product_tabs', 'product_enquiry_tab' );
function product_enquiry_tab( $tabs ) {
    $tabs['anfrage_tab'] = array(
        'title'     => __( 'Anfrage', 'woocommerce' ),
        'priority'  => 50,
        'callback'  => 'product_enquiry_tab_form'
    );
    return $tabs;
}
function product_enquiry_tab_form() {
    global $product;
    //If you want to have product ID also
    //$product_id = $product->id;
    $subject    =   "Anfrage zu ".$product->post->post_title;
    echo "<h2>".$subject."</h2>";
    echo do_shortcode('[contact-form-7 id="1" title="Kontaktformular 1"]'); ?>
    <script>
        (function($){
            <?php if ($product->is_type( 'simple' )) { ?>
                    $(".product_name").val("<?php echo $subject." (Art.-Nr.: ".$product->get_sku().")"; ?>"); <?php
                } elseif( $product->is_type( 'variable' ) ){ 
                    $available_variations = $product->get_available_variations();
                    foreach ($available_variations as $key => $value) { ?>
                        $(".product_name").val("<?php echo $subject." (Art.-Nr.: ".$value['sku'].")"; ?>");
                    <?php }
                } ?>
        })(jQuery);
    </script>
<?php
}

<table style="width:100%">
  <tr>
    <td colspan="2"><label class="product_subject"> [text your-subject class:product_name] </label></td>
  </tr>
  <tr>
    <td><label> [text* your-name placeholder"Ihr Name"] </label></td>
    <td><label> [email* your-email placeholder"E-Mail-Adresse"] </label></td>
  </tr>
  <tr>
    <td colspan="2"><label> [textarea* your-message placeholder"Ihre Nachricht"] </label></td>
  </tr>
  <tr>
    <td>[submit "Senden"]</td>
  </tr>
</table>

<?php
function product_enquiry_tab_form() {
    global $product;
    //If you want to have product ID also
    //$product_id = $product->id;
    $artikelnr    =   " ";
    $subject    =   "Anfrage zu ".$product->post->post_title;
    echo "<h2>".$subject."</h2>";
    echo do_shortcode('[contact-form-7 id="1882" title="Kontaktformular 1"]'); ?>
    <script>
        (function($){
            <?php if ($product->is_type( 'simple' )) { ?>   // Einfaches Produkt
                    $(".product_name").val("<?php echo $subject." (Art.-Nr.: ".$product->get_sku().")"; ?>"); 
            <?php } elseif( $product->is_type( 'variable' ) ){ ?>   // Variables Produkt
                    $(".product_name").val("<?php echo $subject." Hauptartikel"; ?>"); // erster Aufruf
                    $( ".variations_form" ).on( "woocommerce_variation_select_change", function () {   // wechsel der Auswahloption
                        console.log("change");  
                        $(".product_name").val("<?php echo $subject." Hauptartikel"; ?>"); // wenn keine Variation ausgewählt wurde
                        $( document ).ready( function($) {
                            $( '.variations_form' ).each( function() {
                                // when variation is found, do something
                                $(this).on( 'found_variation', function( event, vari ) {   // Variables Produkt wird als Objekt aufgerufen                                          
                                    console.log(vari);      // Zeigt Object in der Konsole
                                    console.log(vari.sku);  // Zeigt Artikelnummer in der Konsole
                                    <?php $artikelnr = vari.sku; ?>    // Qjuery nach PHP ???
                                    $(".product_name").val("<?php echo $subject." (Art.-Nr.: ".$artikelnr.")"; ?>");
                                });
                            });
                        });
                    });                         
            <?php } ?>
        })(jQuery);
    </script>
<?php
}
?>