From 78c1b3de882201262af268a0bfc8d5d30e9ad2e9 Mon Sep 17 00:00:00 2001
From: Valery Buchinsky <djmute@abv.bg>
Date: Tue, 14 Nov 2023 11:26:16 +0200
Subject: [PATCH] do not overwrite page annotations when there already were
 some

refs #198
---
 .../src/pdflibAddPlaceholder.js                    | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/packages/placeholder-pdf-lib/src/pdflibAddPlaceholder.js b/packages/placeholder-pdf-lib/src/pdflibAddPlaceholder.js
index a80fd321..52fd91a6 100644
--- a/packages/placeholder-pdf-lib/src/pdflibAddPlaceholder.js
+++ b/packages/placeholder-pdf-lib/src/pdflibAddPlaceholder.js
@@ -45,7 +45,7 @@ export const pdflibAddPlaceholder = ({
     subFilter = SUBFILTER_ADOBE_PKCS7_DETACHED,
     widgetRect = [0, 0, 0, 0],
 }) => {
-    const pages = pdfDoc.getPages();
+    const page = pdfDoc.getPage(0);
 
     // Create a placeholder where the the last 3 parameters of the
     // actual range will be replaced when signing is done.
@@ -85,15 +85,17 @@ export const pdflibAddPlaceholder = ({
         V: signatureDictRef,
         T: PDFString.of('Signature1'),
         F: ANNOTATION_FLAGS.PRINT,
-        P: pages[0].ref,
+        P: page.ref,
     }, pdfDoc.index);
     const widgetDictRef = pdfDoc.context.register(widgetDict);
 
     // Annotate the widget on the first page
-    pages[0].node.set(
-        PDFName.of('Annots'),
-        pdfDoc.context.obj([widgetDictRef]),
-    );
+    let annotations = page.node.lookupMaybe(PDFName.of('Annots'), PDFArray);
+    if (typeof annotations === 'undefined') {
+        annotations = pdfDoc.context.obj([]);
+    }
+    annotations.push(widgetDictRef);
+    page.node.set(PDFName.of('Annots'), annotations);
 
     // Add an AcroForm or update the existing one
     let acroForm = pdfDoc.catalog.lookupMaybe(PDFName.of('AcroForm'), PDFDict);