From 5220f8ca44e1a34b8de37049bf4b8c71d02514dd Mon Sep 17 00:00:00 2001
From: schroda <50052685+schroda@users.noreply.github.com>
Date: Wed, 25 Dec 2024 23:50:07 +0100
Subject: [PATCH] Prevent unnecessary "page spread state" updates

Only update state in case it has changed
---
 src/modules/reader/components/viewer/ReaderViewer.tsx | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/modules/reader/components/viewer/ReaderViewer.tsx b/src/modules/reader/components/viewer/ReaderViewer.tsx
index 6c703796..c1c3feb4 100644
--- a/src/modules/reader/components/viewer/ReaderViewer.tsx
+++ b/src/modules/reader/components/viewer/ReaderViewer.tsx
@@ -172,7 +172,12 @@ const BaseReaderViewer = forwardRef(
                 if (readingMode === ReadingMode.DOUBLE_PAGE) {
                     const img = new Image();
                     img.onload = () => {
-                        setPagesToSpreadState((prevState) => prevState.toSpliced(index, 1, isSpreadPage(img)));
+                        const isSpreadPageFlag = isSpreadPage(img);
+                        if (pagesToSpreadState[index] === isSpreadPageFlag) {
+                            return;
+                        }
+
+                        setPagesToSpreadState((prevState) => prevState.toSpliced(index, 1, isSpreadPageFlag));
                     };
                     img.src = url;
                 }