From 5645d5bccc7f58be2b2d7a2641d513e299099667 Mon Sep 17 00:00:00 2001
From: Timothy Jaeryang Baek <tim@openwebui.com>
Date: Sun, 1 Mar 2026 14:38:10 -0600
Subject: [PATCH] refac

---
 src/lib/components/chat/FileNav.svelte        |  11 ++
 .../chat/FileNav/FilePreview.svelte           |  10 +-
 src/lib/components/common/PDFViewer.svelte    | 135 ++++++++++++++----
 3 files changed, 123 insertions(+), 33 deletions(-)

diff --git a/src/lib/components/chat/FileNav.svelte b/src/lib/components/chat/FileNav.svelte
index 124be5981..84ad18a71 100644
--- a/src/lib/components/chat/FileNav.svelte
+++ b/src/lib/components/chat/FileNav.svelte
@@ -477,6 +477,17 @@
 					</button>
 				</Tooltip>
 			{/if}
+			{#if filePdfData !== null}
+				<Tooltip content={$i18n.t('Reset view')}>
+					<button
+						class="shrink-0 p-1 rounded hover:bg-gray-100 dark:hover:bg-gray-800 transition text-gray-400 dark:text-gray-500 hover:text-gray-600 dark:hover:text-gray-400"
+						on:click={() => filePreviewRef?.resetPdfView()}
+						aria-label={$i18n.t('Reset view')}
+					>
+						<Reset className="size-3.5" />
+					</button>
+				</Tooltip>
+			{/if}
 			{#if (isMarkdown || isCsv) && fileContent !== null && !editing}
 				<Tooltip content={showRaw ? $i18n.t('Preview') : $i18n.t('Source')}>
 					<button
diff --git a/src/lib/components/chat/FileNav/FilePreview.svelte b/src/lib/components/chat/FileNav/FilePreview.svelte
index acb6c39a1..8de75e238 100644
--- a/src/lib/components/chat/FileNav/FilePreview.svelte
+++ b/src/lib/components/chat/FileNav/FilePreview.svelte
@@ -6,6 +6,8 @@
 	import Spinner from '../../common/Spinner.svelte';
 	import PDFViewer from '../../common/PDFViewer.svelte';
 
+	let pdfViewerRef: PDFViewer;
+
 	const i18n = getContext('i18n');
 
 	export let selectedFile: string | null = null;
@@ -135,13 +137,17 @@
 		}
 	};
 
+	export const resetPdfView = () => {
+		pdfViewerRef?.resetView();
+	};
+
 	onDestroy(() => {
 		disposePanzoom();
 	});
 </script>
 
 <div
-	class="flex-1 {fileImageUrl !== null || filePdfData !== null
+	class="flex-1 {fileImageUrl !== null
 		? 'overflow-hidden'
 		: 'overflow-y-auto'} min-h-0 relative h-full"
 >
@@ -158,7 +164,7 @@
 			/>
 		</div>
 	{:else if filePdfData !== null}
-		<PDFViewer data={filePdfData} className="w-full h-full" />
+		<PDFViewer bind:this={pdfViewerRef} data={filePdfData} className="w-full h-full" />
 	{:else if fileContent !== null}
 		{#if isMarkdown && !showRaw}
 			<div class="prose dark:prose-invert max-w-full text-sm p-3">
diff --git a/src/lib/components/common/PDFViewer.svelte b/src/lib/components/common/PDFViewer.svelte
index e7a25f308..dba72fd4e 100644
--- a/src/lib/components/common/PDFViewer.svelte
+++ b/src/lib/components/common/PDFViewer.svelte
@@ -1,12 +1,8 @@
 <script lang="ts">
-	import { onMount, onDestroy, getContext } from 'svelte';
+	import { onMount, onDestroy } from 'svelte';
 	import pdfWorkerUrl from 'pdfjs-dist/build/pdf.worker.mjs?url';
 	import panzoom, { type PanZoom } from 'panzoom';
 	import Spinner from './Spinner.svelte';
-	import Tooltip from './Tooltip.svelte';
-	import Reset from '../icons/Reset.svelte';
-
-	const i18n = getContext('i18n');
 
 	export let url: string | null = null;
 	export let data: ArrayBuffer | Uint8Array | null = null;
@@ -18,6 +14,7 @@
 	let error = '';
 	let pdfDoc: any = null;
 	let pzInstance: PanZoom | null = null;
+	let zoomLevel = 1;
 
 	const initPanzoom = () => {
 		if (pzInstance) {
@@ -27,15 +24,50 @@
 			pzInstance = panzoom(sceneElement, {
 				bounds: true,
 				boundsPadding: 0.1,
-				zoomSpeed: 0.065
+				zoomSpeed: 0.065,
+				beforeWheel: (e) => {
+					// Only zoom on pinch (ctrlKey / metaKey); let normal scroll pass through
+					if (!e.ctrlKey && !e.metaKey) {
+						return true; // returning true cancels the panzoom wheel handling
+					}
+					return false;
+				},
+				beforeMouseDown: (e) => {
+					// Only allow drag-to-pan when zoomed in (not at default scale)
+					const transform = pzInstance?.getTransform();
+					if (transform && Math.abs(transform.scale - 1) < 0.01) {
+						return true; // cancel panzoom mouse handling at 1x — allow text selection / normal interaction
+					}
+					return false;
+				}
+			});
+			pzInstance.on('zoom', () => {
+				zoomLevel = pzInstance?.getTransform()?.scale ?? 1;
 			});
 		}
 	};
 
-	const resetView = () => {
+	const zoomIn = () => {
+		if (!pzInstance || !outerContainer) return;
+		const cx = outerContainer.clientWidth / 2;
+		const cy = outerContainer.clientHeight / 2;
+		pzInstance.zoomTo(cx, cy, 1.25); // +25%
+		zoomLevel = pzInstance.getTransform().scale;
+	};
+
+	const zoomOut = () => {
+		if (!pzInstance || !outerContainer) return;
+		const cx = outerContainer.clientWidth / 2;
+		const cy = outerContainer.clientHeight / 2;
+		pzInstance.zoomTo(cx, cy, 0.8); // -20% (inverse of 1.25)
+		zoomLevel = pzInstance.getTransform().scale;
+	};
+
+	export const resetView = () => {
 		if (pzInstance) {
 			pzInstance.moveTo(0, 0);
 			pzInstance.zoomAbs(0, 0, 1);
+			zoomLevel = 1;
 		}
 	};
 
@@ -45,20 +77,24 @@
 		// Clear previous canvases
 		sceneElement.innerHTML = '';
 
+		const dpr = window.devicePixelRatio || 1;
+
 		for (let i = 1; i <= pdfDoc.numPages; i++) {
 			const page = await pdfDoc.getPage(i);
 			const viewport = page.getViewport({ scale: 1 });
 
 			// Scale to fit container width
 			const containerWidth = outerContainer?.clientWidth || 800;
-			const scale = containerWidth / viewport.width;
-			const scaledViewport = page.getViewport({ scale });
+			const cssScale = containerWidth / viewport.width;
+			const renderScale = cssScale * dpr;
+			const scaledViewport = page.getViewport({ scale: renderScale });
 
 			const canvas = document.createElement('canvas');
 			canvas.width = scaledViewport.width;
 			canvas.height = scaledViewport.height;
-			canvas.style.width = '100%';
-			canvas.style.height = 'auto';
+			// CSS size stays at the CSS-pixel dimensions for layout
+			canvas.style.width = `${Math.round(cssScale * viewport.width)}px`;
+			canvas.style.height = `${Math.round(cssScale * viewport.height)}px`;
 			canvas.style.display = 'block';
 
 			if (i > 1) {
@@ -119,31 +155,68 @@
 	});
 </script>
 
-<div class="relative overflow-hidden {className}" bind:this={outerContainer}>
-	<div bind:this={sceneElement} class="w-full">
-		{#if loading}
-			<div class="flex items-center justify-center h-full">
-				<Spinner className="size-5" />
-			</div>
-		{/if}
+<div class="relative {className}">
+	<div class="overflow-y-auto h-full" bind:this={outerContainer}>
+		<div bind:this={sceneElement} class="w-full">
+			{#if loading}
+				<div class="flex items-center justify-center h-full">
+					<Spinner className="size-5" />
+				</div>
+			{/if}
 
-		{#if error}
-			<div class="flex items-center justify-center h-full text-sm text-red-500">
-				{error}
-			</div>
-		{/if}
+			{#if error}
+				<div class="flex items-center justify-center h-full text-sm text-red-500">
+					{error}
+				</div>
+			{/if}
+		</div>
 	</div>
 
 	{#if !loading && !error && pdfDoc}
-		<div class="absolute top-2 right-2 z-10">
-			<Tooltip content={$i18n.t('Reset view')}>
-				<button
-					class="p-1.5 rounded-lg bg-white/80 dark:bg-gray-850/80 backdrop-blur-sm shadow-sm hover:bg-gray-100 dark:hover:bg-gray-800 transition text-gray-500 dark:text-gray-400"
-					on:click={resetView}
+		<div
+			class="absolute bottom-3 left-1/2 -translate-x-1/2 z-10 flex items-center gap-0.5 rounded-lg bg-white/90 dark:bg-gray-850/90 backdrop-blur-sm shadow-lg border border-gray-200/60 dark:border-gray-700/60 px-1 py-0.5"
+		>
+			<button
+				class="p-1.5 rounded-md hover:bg-gray-100 dark:hover:bg-gray-800 transition text-gray-500 dark:text-gray-400"
+				on:click={zoomOut}
+				aria-label="Zoom out"
+			>
+				<svg
+					xmlns="http://www.w3.org/2000/svg"
+					viewBox="0 0 20 20"
+					fill="currentColor"
+					class="size-3.5"
 				>
-					<Reset className="size-4" />
-				</button>
-			</Tooltip>
+					<path
+						fill-rule="evenodd"
+						d="M4 10a.75.75 0 0 1 .75-.75h10.5a.75.75 0 0 1 0 1.5H4.75A.75.75 0 0 1 4 10Z"
+						clip-rule="evenodd"
+					/>
+				</svg>
+			</button>
+			<button
+				class="px-1.5 py-1 min-w-[3rem] text-center text-[11px] font-medium text-gray-500 dark:text-gray-400 rounded-md hover:bg-gray-100 dark:hover:bg-gray-800 transition tabular-nums"
+				on:click={resetView}
+				aria-label="Reset zoom"
+			>
+				{Math.round(zoomLevel * 100)}%
+			</button>
+			<button
+				class="p-1.5 rounded-md hover:bg-gray-100 dark:hover:bg-gray-800 transition text-gray-500 dark:text-gray-400"
+				on:click={zoomIn}
+				aria-label="Zoom in"
+			>
+				<svg
+					xmlns="http://www.w3.org/2000/svg"
+					viewBox="0 0 20 20"
+					fill="currentColor"
+					class="size-3.5"
+				>
+					<path
+						d="M10.75 4.75a.75.75 0 0 0-1.5 0v4.5h-4.5a.75.75 0 0 0 0 1.5h4.5v4.5a.75.75 0 0 0 1.5 0v-4.5h4.5a.75.75 0 0 0 0-1.5h-4.5v-4.5Z"
+					/>
+				</svg>
+			</button>
 		</div>
 	{/if}
 </div>