WooCommerce add product image to gallery automatically (if gallery is empty)

Question

In WooCommerce, a product can have product image (single image) & product gallery (multiple images).

When I select a product image for a product, I want it to automatically add up to the product gallery as well.

One important thing: it should check if the product image is already in the gallery or not (so the gallery won't have a duplicate image).

Is there a php function for that?

(I suspect these lines of code might help to create the function)

Answer 1

I solved it by adding the product image to the gallery array in the template itself.

<?php
    global $product;
    $attachment_ids = $product->get_gallery_image_ids();
    $product_image_id = $product->get_image_id();

    // Add product image to gallery if its not there.
    // (This will prevent empty galleries, and also prevent duplicate images)
    if (!in_array($product_image_id, $attachment_ids)) {
        array_unshift($attachment_ids, $product_image_id);
    }

    foreach ($attachment_ids as $attachment_id) :
        $attachment_full_url = wp_get_attachment_image_src($attachment_id, 'full')[0];
    ?>
        <div class="swiper-slide"><a href="<?php echo $attachment_full_url; ?>"><?php echo wp_get_attachment_image($attachment_id, 'woocommerce_single'); ?></a></div>
    <?php
    endforeach;
?>

However, a better solution would be to actually add the product image to the gallery itself, instead of a having a template code do that.