Product::get_gallery_ids()

	public function get_gallery_ids() {
		$data = get_post_meta( $this->post_id, self::GALLERY_META_KEY, true );

		$gallery = is_array( $data ) ? array_filter( array_map( 'intval', $data ) ) : [];

		if ( empty( $gallery ) ) {
			$default = get_option( Product_Single::DEFAULT_IMAGE, 0 );
			if ( ! empty( $default ) ) {
				$gallery = [ absint( $default ) ];
			}
		}

		/**
		 * Filter the images that display in a product gallery
		 *
		 * @param int[] $gallery The IDs of images in the gallery
		 */
		return apply_filters( 'bigcommerce/product/gallery', $gallery );
	}