Chore/v2/fix auto zoom (#4903)

frontend/src/core/components/viewer/LocalEmbedPDF.tsx

@@ -191,7 +191,6 @@ export function LocalEmbedPDF({ file, url, enableAnnotations = false, onSignatur
           height: '100%',
           width: '100%',
           position: 'relative',
-          overflow: 'hidden',
           flex: 1,
           minHeight: 0,
           minWidth: 0,
@@ -287,8 +286,6 @@ export function LocalEmbedPDF({ file, url, enableAnnotations = false, onSignatur
               minHeight: 0,
               minWidth: 0,
               contain: 'strict',
-              display: 'flex',
-              justifyContent: 'center',
             }}
           >
           <Scroller

frontend/src/core/components/viewer/ZoomAPIBridge.tsx

@@ -7,9 +7,7 @@ import {
   determineAutoZoom,
   DEFAULT_FALLBACK_ZOOM,
   DEFAULT_VISIBILITY_THRESHOLD,
-  measureRenderedPageRect,
   useFitWidthResize,
-  ZoomViewport,
 } from '@app/utils/viewerZoom';
 import { getFirstPageAspectRatioFromStub } from '@app/utils/pageMetadata';
 
@@ -73,18 +71,6 @@ export function ZoomAPIBridge() {
     }
   }, [spreadMode, zoomState?.zoomLevel, scheduleAutoZoom, requestFitWidth]);
 
-  const getViewportSnapshot = useCallback((): ZoomViewport | null => {
-    if (!zoomState || typeof zoomState !== 'object') {
-      return null;
-    }
-
-    if ('viewport' in zoomState) {
-      const candidate = (zoomState as { viewport?: ZoomViewport | null }).viewport;
-      return candidate ?? null;
-    }
-
-    return null;
-  }, [zoomState]);
 
   const isManagedZoom =
     !!zoom &&
@@ -119,7 +105,7 @@ export function ZoomAPIBridge() {
     }
 
     const fitWidthZoom = zoomState.currentZoomLevel;
-    if (!fitWidthZoom || fitWidthZoom <= 0) {
+    if (!fitWidthZoom || fitWidthZoom <= 0 || fitWidthZoom === 1) {
       return;
     }
 
@@ -137,37 +123,23 @@ export function ZoomAPIBridge() {
       const pagesPerSpread = currentSpreadMode !== SpreadMode.None ? 2 : 1;
       const metadataAspectRatio = getFirstPageAspectRatioFromStub(firstFileStub);
 
-      const viewport = getViewportSnapshot();
-
       if (cancelled) {
         return;
       }
 
-      const metrics = viewport ?? {};
-      const viewportWidth =
-        metrics.clientWidth ?? metrics.width ?? window.innerWidth ?? 0;
-      const viewportHeight =
-        metrics.clientHeight ?? metrics.height ?? window.innerHeight ?? 0;
+      const viewportWidth = window.innerWidth ?? 0;
+      const viewportHeight = window.innerHeight ?? 0;
 
       if (viewportWidth <= 0 || viewportHeight <= 0) {
         return;
       }
 
-      const pageRect = await measureRenderedPageRect({
-        shouldCancel: () => cancelled,
-      });
-      if (cancelled) {
-        return;
-      }
-
       const decision = determineAutoZoom({
         viewportWidth,
         viewportHeight,
         fitWidthZoom,
         pagesPerSpread,
-        pageRect: pageRect
-          ? { width: pageRect.width, height: pageRect.height }
-          : undefined,
+        pageRect: undefined,
         metadataAspectRatio: metadataAspectRatio ?? null,
         visibilityThreshold: DEFAULT_VISIBILITY_THRESHOLD,
         fallbackZoom: DEFAULT_FALLBACK_ZOOM,
@@ -197,7 +169,6 @@ export function ZoomAPIBridge() {
     firstFileId,
     firstFileStub,
     requestFitWidth,
-    getViewportSnapshot,
     autoZoomTick,
     spreadMode,
     triggerImmediateZoomUpdate,