From 7c5e9cf8be1c833ecaafbe963959755a53b6556e Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Sat, 15 Jun 2024 17:39:59 +0200
Subject: [PATCH 1/2] Ensure that saving, in the viewer, works for partially
 loaded documents

Currently saving a modified PDF document may fail *intermittently*, if it's triggered before the entire document has been downloaded.
When saving was originally added we only supported forms, and such PDF documents are usually small/simple enough for this issue to be difficult to trigger. However, with editing-support now available as well it's possible to modify much larger documents and this issue thus becomes easier to trigger.

One way to reproduce this issue *consistently* is to:
 - Open http://localhost:8888/web/viewer.html?file=/test/pdfs/pdf.pdf#disableHistory=true&disableStream=true&disableAutoFetch=true
 - Add an annotation on the first page, it doesn't matter what kind.
 - Save the document.
 - Open the resulting document, and notice that with the `master` branch the annotation is missing.
---
 web/app.js | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/web/app.js b/web/app.js
index 927d7143ede44..d8dd9e95389b9 100644
--- a/web/app.js
+++ b/web/app.js
@@ -1109,8 +1109,6 @@ const PDFViewerApplication = {
     await this.pdfScriptingManager.dispatchWillSave();
 
     try {
-      this._ensureDownloadComplete();
-
       const data = await this.pdfDocument.saveDocument();
       this.downloadManager.download(
         data,
@@ -1119,8 +1117,7 @@ const PDFViewerApplication = {
         options
       );
     } catch (reason) {
-      // When the PDF document isn't ready, or the PDF file is still
-      // downloading, simply fallback to a "regular" download.
+      // When the PDF document isn't ready, fallback to a "regular" download.
       console.error(`Error when saving the document: ${reason.message}`);
       await this.download(options);
     } finally {

From f4912db2ae58cec0c2e9b6e302f0ae6e6c15d252 Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Sat, 15 Jun 2024 17:45:38 +0200
Subject: [PATCH 2/2] Remove the `_ensureDownloadComplete` helper method in
 `web/app.js`

After the previous commit this method has only a single call-site, hence we can inline the needed part of that check directly in `PDFViewerApplication.download` instead.
---
 web/app.js | 16 +++-------------
 1 file changed, 3 insertions(+), 13 deletions(-)

diff --git a/web/app.js b/web/app.js
index d8dd9e95389b9..8bcb86f20d69e 100644
--- a/web/app.js
+++ b/web/app.js
@@ -1073,22 +1073,12 @@ const PDFViewerApplication = {
     );
   },
 
-  /**
-   * @private
-   */
-  _ensureDownloadComplete() {
-    if (this.pdfDocument && this.downloadComplete) {
-      return;
-    }
-    throw new Error("PDF document not downloaded.");
-  },
-
   async download(options = {}) {
     let data;
     try {
-      this._ensureDownloadComplete();
-
-      data = await this.pdfDocument.getData();
+      if (this.downloadComplete) {
+        data = await this.pdfDocument.getData();
+      }
     } catch {
       // When the PDF document isn't ready, or the PDF file is still
       // downloading, simply download using the URL.