/**
  * Bulk booking requests.
  *
  * @param array $post_ids Array of WC_Order ID's
  */
 static function bulk_send_booking($post_ids)
 {
     foreach ($post_ids as $post_id) {
         $order = new Bring_WC_Order_Adapter(new WC_Order($post_id));
         if (!$order->has_booking_consignments()) {
             self::send_booking($order->order);
         }
     }
 }
 static function open_pdfs()
 {
     add_submenu_page(null, 'Download', 'Download', 'manage_woocommerce', 'bring_labels', function () {
         if (!isset($_GET['order_ids']) || $_GET['order_ids'] == '') {
             return;
         }
         $current_user = wp_get_current_user();
         // ID 0 is a not an user.
         if ($current_user->ID == 0) {
             exit;
         }
         // Admins and managers can download all orders.
         $can_download = in_array('manage_woocommerce', $current_user->roles) || in_array('administrator', $current_user->roles);
         if (!$can_download) {
             exit;
         }
         $order_ids = explode(',', $_GET['order_ids']);
         $files_to_merge = [];
         foreach ($order_ids as $order_id) {
             $order = new Bring_WC_Order_Adapter(new WC_Order($order_id));
             if (!$order->has_booking_consignments()) {
                 continue;
             }
             $consignments = $order->get_booking_consignments();
             foreach ($consignments as $consignment) {
                 $confirmation = $consignment->confirmation;
                 $consignment_number = $confirmation->consignmentNumber;
                 $file_path = Bring_Booking_Labels::get_file_path($order->order->id, $consignment_number);
                 if (file_exists($file_path)) {
                     $files_to_merge[] = Bring_Booking_Labels::get_file_path($order->order->id, $consignment_number);
                 }
             }
         }
         include_once FRAKTGUIDEN_PLUGIN_PATH . '/vendor/myokyawhtun/pdfmerger/PDFMerger.php';
         $merger = new PDFMerger();
         foreach ($files_to_merge as $file) {
             $merger->addPDF($file);
         }
         $merge_result_file = Bring_Booking_Labels::get_local_dir() . '/labels-merged.pdf';
         $merger->merge('file', $merge_result_file);
         header("Content-Length: " . filesize($merge_result_file));
         header("Content-type: application/pdf");
         header("Content-disposition: inline; filename=" . basename($merge_result_file));
         header('Expires: 0');
         header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
         // Workaround for Chrome's inline pdf viewer
         ob_clean();
         flush();
         readfile($merge_result_file);
         exit;
     });
 }