Merge pull request '避免页面更新打断图片下载' (#76) from codex/preserve-active-image-downloads-20261111 into main

app/api/canvas/local-edit/route.ts

@@ -976,7 +976,8 @@ export async function POST(request: NextRequest) {
     const annotatedFilename = `canvas-local-edit-${Date.now()}-${Math.random().toString(36).slice(2, 8)}.png`;
     const annotatedUpload = await uploadFile(
       annotatedFilename,
-      toArrayBuffer(annotatedBuffer)
+      toArrayBuffer(annotatedBuffer),
+      { preferQiniuForm: true }
     );
     const prompt = buildLocalEditPrompt(regions);
     const manualRegionReferenceImageUrls = regions.flatMap((region) =>

app/api/image-proxy/route.ts

@@ -133,15 +133,13 @@ function buildImageResponse(
     etag: string;
     vary?: string;
     cacheStatus?: "HIT" | "MISS";
-    cacheControl?: string;
-    attachment?: boolean;
   }
 ) {
   const headers: Record<string, string> = {
     "Content-Type": params.contentType,
     "Content-Length": String(body.length),
     ETag: params.etag,
-    "Cache-Control": params.cacheControl || "public, max-age=31536000, immutable, stale-while-revalidate=86400",
+    "Cache-Control": "public, max-age=31536000, immutable, stale-while-revalidate=86400",
   };
   if (params.vary) {
     headers.Vary = params.vary;
@@ -149,11 +147,6 @@ function buildImageResponse(
   if (params.cacheStatus) {
     headers["X-Image-Proxy-Cache"] = params.cacheStatus;
   }
-  if (params.attachment) {
-    headers["Content-Disposition"] = "attachment";
-    headers["X-Content-Type-Options"] = "nosniff";
-    headers["Content-Security-Policy"] = "default-src 'none'; sandbox";
-  }
   return new NextResponse(body, {
     status: 200,
     headers,
@@ -460,20 +453,29 @@ export async function GET(request: NextRequest) {
       if (original) return downloadFailure("Source is not an image");
       return NextResponse.json({ error: "Upstream is not an image" }, { status: 400 });
     }
+    if (original) {
+      if (upstreamResponse.status !== 200 || !upstreamResponse.body) {
+        await upstreamResponse.body?.cancel();
+        return downloadFailure("源图片传输中断，请重试");
+      }
+      const headers = new Headers({
+        "Content-Type": contentType,
+        "Content-Disposition": "attachment",
+        "Cache-Control": "private, no-store",
+        "X-Content-Type-Options": "nosniff",
+        "Content-Security-Policy": "default-src 'none'; sandbox",
+      });
+      const length = upstreamResponse.headers.get("content-length");
+      const encoding = upstreamResponse.headers.get("content-encoding");
+      if (length && (!encoding || encoding.toLowerCase() === "identity")) headers.set("Content-Length", length);
+      return new NextResponse(upstreamResponse.body, { headers });
+    }
     try {
       originalBuffer = Buffer.from(await upstreamResponse.arrayBuffer());
     } catch (error) {
       return upstreamFailure(error);
     }
   }
-  if (original) {
-    return buildImageResponse(originalBuffer, {
-      contentType,
-      etag: `"${crypto.createHash("sha256").update(originalBuffer).digest("hex")}"`,
-      cacheControl: "private, no-store",
-      attachment: true,
-    });
-  }
   const isSvg = contentType.toLowerCase().includes("image/svg");
   const isGif = contentType.toLowerCase().includes("image/gif");
 

app/api/watermark-remove/route.ts

@@ -6,6 +6,7 @@ import { eq } from "drizzle-orm";
 import { uploadFile } from "@/lib/storage/service";
 import {
   createMediaAssetRelation,
+  getDefaultStorageConfig,
   getPointsSystemConfig,
   getMediaAssetsByUserAndUrls,
   upsertMediaAsset,
@@ -21,6 +22,27 @@ export const maxDuration = 600;
 const WATERMARK_SYNC_WAIT_TIMEOUT_MS = 20_000;
 const WATERMARK_POLL_INTERVAL_MS = 1200;
 
+async function resolveStoredQiniuImageUrl(source: string): Promise<string | null> {
+  const config = await getDefaultStorageConfig().catch(() => null);
+  if (config?.type !== "qiniu-kodo" || !config.isEnabled || !config.publicUrl) return null;
+
+  try {
+    const base = new URL(config.publicUrl);
+    const url = new URL(source);
+    const prefix = base.pathname.replace(/\/$/, "") + "/";
+    if (base.protocol !== "https:" || url.origin !== base.origin ||
+        url.username || url.password || url.search || url.hash ||
+        !url.pathname.startsWith(prefix)) return null;
+
+    const objectKey = url.pathname.slice(prefix.length);
+    return /^uploads\/(?:direct\/[0-9a-f-]{36}\/)?[\w.-]+$/i.test(objectKey)
+      ? url.toString()
+      : null;
+  } catch {
+    return null;
+  }
+}
+
 // 获取去水印API配置
 async function getWatermarkRemoveConfig() {
   try {
@@ -131,13 +153,16 @@ async function persistWatermarkResult(params: {
   processing_time?: number;
 }> {
   try {
+    let resultUrl = await resolveStoredQiniuImageUrl(params.processedImageUrl);
+    if (!resultUrl) {
       const imageResponse = await fetch(params.processedImageUrl);
       if (!imageResponse.ok) {
         throw new Error("下载处理后的图片失败");
       }
       const imageBuffer = await imageResponse.arrayBuffer();
       const filename = `watermark-removed-${Date.now()}.png`;
-    const uploadResult = await uploadFile(filename, imageBuffer);
+      resultUrl = (await uploadFile(filename, imageBuffer)).url;
+    }
 
     let saved = false;
     let saveError: unknown = null;
@@ -150,8 +175,8 @@ async function persistWatermarkResult(params: {
       try {
         ([savedImage] = await db.insert(generatedImage).values({
           userId: params.userId,
-          thumbnailUrl: uploadResult.url,
-          originalUrl: uploadResult.url,
+          thumbnailUrl: resultUrl,
+          originalUrl: resultUrl,
           imageSize: "2K",
           prompt: "去水印处理",
           modelId: "watermark-remove",
@@ -184,9 +209,9 @@ async function persistWatermarkResult(params: {
           mediaType: "image",
           sourceType: "edited",
           status: "ready",
-          originalUrl: uploadResult.url,
-          previewUrl: uploadResult.url,
-          thumbnailUrl: uploadResult.url,
+          originalUrl: resultUrl,
+          previewUrl: resultUrl,
+          thumbnailUrl: resultUrl,
           displayName: "去水印处理",
           prompt: "去水印处理",
           modelId: "watermark-remove",
@@ -217,8 +242,8 @@ async function persistWatermarkResult(params: {
 
     return {
       success: true,
-      original_url: uploadResult.url,
-      thumbnail_url: uploadResult.url,
+      original_url: resultUrl,
+      thumbnail_url: resultUrl,
       processing_time:
         typeof params.startedAt === "number" ? (Date.now() - params.startedAt) / 1000 : undefined,
     };
@@ -362,7 +387,7 @@ export async function POST(request: NextRequest) {
     const body = await request.json();
     const { image_url } = body;
 
-    if (!image_url) {
+    if (typeof image_url !== "string" || !image_url) {
       return NextResponse.json(
         { error: "请提供图片URL" },
         { status: 400 }
@@ -413,8 +438,11 @@ export async function POST(request: NextRequest) {
         );
       }
     } 
-    // 如果是 HTTP/HTTPS URL，下载后重新上传确保公网可访问
+    // 七牛上的公开图片可以直接交给去水印服务读取。
     else if (image_url.startsWith("http://") || image_url.startsWith("https://")) {
+      const storedImageUrl = await resolveStoredQiniuImageUrl(image_url);
+      publicImageUrl = storedImageUrl || image_url;
+      if (!storedImageUrl) {
         try {
           console.log("[WatermarkRemove] 下载原图并上传到S3...");
           const imageResponse = await fetch(image_url);
@@ -423,14 +451,11 @@ export async function POST(request: NextRequest) {
           }
           const imageBuffer = await imageResponse.arrayBuffer();
           const filename = `watermark-input-${Date.now()}.jpg`;
-        const uploadResult = await uploadFile(filename, imageBuffer);
-        publicImageUrl = uploadResult.url;
+          publicImageUrl = (await uploadFile(filename, imageBuffer)).url;
           console.log("[WatermarkRemove] 图片已上传到S3:", publicImageUrl);
         } catch (downloadError) {
-        console.error("[WatermarkRemove] 下载/上传原图失败:", downloadError);
-        // 如果下载失败，尝试使用原始URL
-        console.log("[WatermarkRemove] 尝试使用原始URL");
-        publicImageUrl = image_url;
+          console.error("[WatermarkRemove] 下载/上传原图失败，使用原始URL:", downloadError);
+        }
       }
     } else {
       return NextResponse.json(

app/layout.tsx

@@ -4,6 +4,7 @@ import { ThemeProvider } from "@/components/theme-provider";
 import { FaviconUpdater } from "@/components/favicon-updater";
 import { ImageDeliveryOptimizer } from "@/components/image-delivery-optimizer";
 import { AppUpdateNotice } from "@/components/app-update-notice";
+import { PAGE_DOWNLOAD_ACTIVE_ATTRIBUTE } from "@/lib/client/page-refresh";
 import { getSiteSettings } from "@/lib/db/queries";
 
 import "./globals.css";
@@ -142,7 +143,7 @@ const CHUNK_ERROR_RECOVERY_SCRIPT = `\
       showManualRecoveryNotice();
       return;
     }
-    if (lastReloadAt) return;
+    if (lastReloadAt || document.documentElement.hasAttribute('${PAGE_DOWNLOAD_ACTIVE_ATTRIBUTE}')) return;
     var now = Date.now();
     // If storage is blocked, a reload cannot remember its attempt and must not run.
     if (!safeSetSessionStorage(RECOVERY_KEY, String(now))) return;
@@ -153,6 +154,10 @@ const CHUNK_ERROR_RECOVERY_SCRIPT = `\
         showManualRecoveryNotice();
         return;
       }
+      if (document.documentElement.hasAttribute('${PAGE_DOWNLOAD_ACTIVE_ATTRIBUTE}')) {
+        if (safeSetSessionStorage(RECOVERY_KEY, '0')) lastReloadAt = 0;
+        return;
+      }
       window.location.reload();
     }, 800);
   }

components/agents/AgentWorkflowBrandModelPicker.tsx

@@ -3,6 +3,7 @@
 import { useMemo } from "react";
 import useSWR from "swr";
 import { Check, ImageIcon, Loader2, UserRound } from "lucide-react";
+import { AgentPreviewImage } from "@/components/agents/AgentPreviewImage";
 import { Button } from "@/components/ui/button";
 import { cn, fetcher } from "@/lib/utils";
 import { normalizeAgentWorkflowBrandModelConfig } from "@/lib/agents/workflow-brand-model-config";
@@ -229,12 +230,11 @@ export function AgentWorkflowBrandModelPicker({
                       isDark ? "bg-white/[0.04]" : "bg-muted/40"
                     )}
                   >
-                    <img
+                    <AgentPreviewImage
                       src={image.imageUrl}
                       alt={image.displayName || `${normalizedBrand} 模特图`}
                       className="h-full w-full object-cover"
-                      loading="lazy"
-                      decoding="async"
+                      previewWidth={360}
                     />
                     <div className="absolute inset-x-0 top-0 flex items-center justify-between px-2 py-2">
                       <span className="rounded-full bg-black/60 px-2 py-1 text-[11px] text-white">

components/app-update-notice.tsx

@@ -1,14 +1,15 @@
 "use client";
 
-import { useEffect, useState } from "react";
+import { useEffect, useState, useSyncExternalStore } from "react";
 import { Button } from "@/components/ui/button";
 import { AlertDialog, AlertDialogContent, AlertDialogHeader, AlertDialogTitle, AlertDialogDescription, AlertDialogFooter } from "@/components/ui/alert-dialog";
-import { preparePageRefresh } from "@/lib/client/page-refresh";
+import { isPageDownloadActive, preparePageRefresh, subscribeToPageDownloadActivity } from "@/lib/client/page-refresh";
 
 export function AppUpdateNotice() {
   const [availableVersion, setAvailableVersion] = useState("");
   const [refreshing, setRefreshing] = useState(false);
   const [error, setError] = useState("");
+  const downloading = useSyncExternalStore(subscribeToPageDownloadActivity, isPageDownloadActive, () => false);
   useEffect(() => {
     let disposed = false;
     let controller: AbortController | undefined;
@@ -60,7 +61,7 @@ export function AppUpdateNotice() {
       setRefreshing(false);
     }
   };
-  return <AlertDialog open={Boolean(availableVersion)}>
+  return <AlertDialog open={Boolean(availableVersion) && !downloading}>
     <AlertDialogContent className="z-[10001]" overlayClassName="z-[10000]" onEscapeKeyDown={event => event.preventDefault()}>
       <AlertDialogHeader>
         <AlertDialogTitle>平台已更新</AlertDialogTitle>

components/canvas/CanvasChatPanel.tsx

@@ -78,7 +78,7 @@ import {
   type UploadProgress,
 } from "@/lib/client/upload-with-retry";
 import {
-  downloadCanvasImageAsPng,
+  downloadOriginalImage,
   getCanvasImageDownloadErrorMessage,
   type CanvasImageDownloadProgress,
 } from "@/lib/client/canvas-image-download";
@@ -1462,7 +1462,7 @@ function normalizeComposerPreviewTail(text: string, fixedPrefix: string) {
 }
 
 // 获取图片尺寸（保留原图分辨率 + 画布显示尺寸）
-function getImageDimensions(url: string): Promise<{
+function getImageDimensions(source: string | File): Promise<{
   width: number;
   height: number;
   originalWidth: number;
@@ -1470,6 +1470,7 @@ function getImageDimensions(url: string): Promise<{
 }> {
   return new Promise((resolve) => {
     const img = new Image();
+    const objectUrl = typeof source === "string" ? null : URL.createObjectURL(source);
     let settled = false;
     const resolveOnce = (dimensions: {
       width: number;
@@ -1482,9 +1483,11 @@ function getImageDimensions(url: string): Promise<{
       window.clearTimeout(timeout);
       img.onload = null;
       img.onerror = null;
+      if (objectUrl) URL.revokeObjectURL(objectUrl);
       resolve(dimensions);
     };
     const timeout = window.setTimeout(() => {
+      img.removeAttribute("src");
       resolveOnce(DEFAULT_CANVAS_IMAGE_DIMENSIONS);
     }, CANVAS_IMAGE_DIMENSION_TIMEOUT_MS);
 
@@ -1517,7 +1520,7 @@ function getImageDimensions(url: string): Promise<{
       // 加载失败时使用默认尺寸
       resolveOnce(DEFAULT_CANVAS_IMAGE_DIMENSIONS);
     };
-    img.src = url;
+    img.src = objectUrl ?? String(source);
   });
 }
 
@@ -4464,17 +4467,15 @@ export function CanvasChatPanel({
     setDownloadProgress({
       phase: "preparing",
       message: "正在准备原图...",
-      percent: 5,
     });
 
     try {
-      await downloadCanvasImageAsPng({
+      await downloadOriginalImage({
         url: originalUrl,
-        candidates: [raw, buildImageProxyUrl(originalUrl, { delivery: "proxy" })],
         signal: controller.signal,
         onProgress: setDownloadProgress,
       });
-      toast.success("原图已开始下载");
+      toast.success("已开始下载");
     } catch (error) {
       if (controller.signal.aborted) {
         toast.message("已取消下载");
@@ -7806,7 +7807,6 @@ export function CanvasChatPanel({
           existingMessageImageKeys.add(messageImageKey);
         }
 
-        const dimensions = await getImageDimensions(url);
         if (useCanvasStore.getState().projectId !== canvasId || activeChatIdRef.current !== activeChatId) return;
         const compareSourceUrlRaw =
           sourceImageUrls[Math.min(index, Math.max(0, sourceImageUrls.length - 1))] ||
@@ -7839,7 +7839,7 @@ export function CanvasChatPanel({
         const placeholderNode = reservedPlaceholderNode
           ? currentNodes.find((node) => node.id === reservedPlaceholderNode.id) || null
           : null;
-        const size = { width: dimensions.width, height: dimensions.height };
+        const size = placeholderNode?.size || anchorNode?.size || { width: 300, height: 300 };
         const position = placeholderNode
           ? getCenteredReplacementPosition(placeholderNode, size)
           : getAnchoredGenerationPosition({
@@ -7857,8 +7857,6 @@ export function CanvasChatPanel({
           prompt: generationPrompt,
           originalSrc: canUseCompareSource ? compareSourceUrl : undefined,
           metadata: {
-            originalWidth: dimensions.originalWidth,
-            originalHeight: dimensions.originalHeight,
             generationPrompt,
             sourceMessageId: messageId || undefined,
             sourceImageKey,
@@ -9583,7 +9581,6 @@ export function CanvasChatPanel({
             continue;
           }
 
-          const dimensions = await getImageDimensions(url);
           if (cancelled) return;
           const compareSourceUrlRaw =
             nearestUserImageUrls[Math.min(index, Math.max(0, nearestUserImageUrls.length - 1))] ||
@@ -9616,20 +9613,7 @@ export function CanvasChatPanel({
           const placeholderNode = reservedPlaceholderNode
             ? currentNodes.find((node) => node.id === reservedPlaceholderNode.id) || null
             : null;
-          const size = placeholderNode
-            ? { width: dimensions.width, height: dimensions.height }
-            : anchorNode
-            ? {
-                width: Math.max(
-                  1,
-                  Math.round(Number(anchorNode.size?.width || dimensions.width))
-                ),
-                height: Math.max(
-                  1,
-                  Math.round(Number(anchorNode.size?.height || dimensions.height))
-                ),
-              }
-            : { width: dimensions.width, height: dimensions.height };
+          const size = placeholderNode?.size || anchorNode?.size || { width: 300, height: 300 };
           const position = placeholderNode
             ? getCenteredReplacementPosition(placeholderNode, size)
             : getAnchoredGenerationPosition({
@@ -9648,8 +9632,6 @@ export function CanvasChatPanel({
             prompt: generationPrompt || "对话生成",
             originalSrc: canUseCompareSource ? compareSourceUrl : undefined,
             metadata: {
-              originalWidth: dimensions.originalWidth,
-              originalHeight: dimensions.originalHeight,
               generationPrompt: generationPrompt || undefined,
               sourceMessageId: message.id,
               sourceImageKey: imageEntry.sourceImageKey,
@@ -10376,7 +10358,7 @@ export function CanvasChatPanel({
           buildCanvasUploadedImageAttachment({ file, imageUrl, assetId })
         );
 
-        const dimensions = await getImageDimensions(imageUrl);
+        const dimensions = await getImageDimensions(file);
         const nodeIndex = nodes.length + slotIndex;
         const spacing = 20;
         const x = 100 + (nodeIndex % 3) * (dimensions.width + spacing);
@@ -10454,7 +10436,7 @@ export function CanvasChatPanel({
           buildCanvasUploadedImageAttachment({ file, imageUrl, assetId })
         );
 
-        const dimensions = await getImageDimensions(imageUrl);
+        const dimensions = await getImageDimensions(file);
         const nodeIndex = nodes.length + slotIndex;
         const spacing = 20;
         const x = 100 + (nodeIndex % 3) * (dimensions.width + spacing);
@@ -13740,7 +13722,7 @@ export function CanvasChatPanel({
       };
       onUploaded?.(uploadedBase);
       clearComposerUploadProgress(250);
-      const dimensions = await getImageDimensions(imageUrl);
+      const dimensions = await getImageDimensions(file);
       const spacing = 20;
       const x = 100 + (nodeIndex % 3) * (dimensions.width + spacing);
       const y = 100 + Math.floor(nodeIndex / 3) * (dimensions.height + spacing);
@@ -14929,7 +14911,7 @@ export function CanvasChatPanel({
           firstImageUrl = imageUrl;
         }
 
-        const dimensions = await getImageDimensions(imageUrl);
+        const dimensions = await getImageDimensions(file);
         updateUploadedImageAttachmentDimensions(imageUrl, dimensions);
         
         // 获取图片原始尺寸后添加到画布

components/canvas/CanvasImageDownloadProgressDialog.tsx

@@ -28,6 +28,7 @@ export function CanvasImageDownloadProgressDialog({
       : null;
   const loadedLabel = formatBytes(progress.loadedBytes);
   const totalLabel = formatBytes(progress.totalBytes);
+  const converting = progress.phase === "converting";
 
   return createPortal(
     <div
@@ -41,12 +42,12 @@ export function CanvasImageDownloadProgressDialog({
               {progress.phase === "saving" ? (
                 <Download className="h-4 w-4" />
               ) : (
-                <Loader2 className="h-4 w-4 animate-spin" />
+                <Loader2 className="h-4 w-4 motion-safe:animate-spin" />
               )}
             </span>
             <div>
               <div className="text-[14px] font-semibold">下载原图</div>
-              <div className="mt-0.5 text-[12px] text-white/58">{progress.message}</div>
+              <div className="mt-0.5 text-[12px] text-white/58" role="status">{progress.message}</div>
             </div>
           </div>
           {onCancel ? (
@@ -63,14 +64,19 @@ export function CanvasImageDownloadProgressDialog({
 
         <div className="mt-4">
           <div className="mb-2 flex items-center justify-between text-[12px] text-white/55">
-            <span>{loadedLabel && totalLabel ? `${loadedLabel} / ${totalLabel}` : "正在处理文件"}</span>
+            <span>{loadedLabel && totalLabel ? `${loadedLabel} / ${totalLabel}` : converting ? "格式转换中" : "正在处理文件"}</span>
             <span>{percent !== null ? `${percent}%` : "..."}</span>
           </div>
-          <div className="relative h-2 overflow-hidden rounded-full bg-white/10">
+          <div
+            className="relative h-2 overflow-hidden rounded-full bg-white/10"
+            role="progressbar"
+            aria-label={converting ? "图片格式转换" : "图片下载"}
+            aria-valuenow={percent ?? undefined}
+          >
             <div
               className={cn(
                 "absolute inset-y-0 left-0 rounded-full bg-gradient-to-r from-cyan-300 via-sky-400 to-emerald-300",
-                percent === null && "w-1/3 animate-[download-indeterminate_1.15s_ease-in-out_infinite]"
+                percent === null && "w-1/3 motion-safe:animate-[download-indeterminate_1.15s_ease-in-out_infinite]"
               )}
               style={percent !== null ? { width: `${percent}%` } : undefined}
             />

components/canvas/nodes/ImageNode.tsx

@@ -178,7 +178,7 @@ import {
 } from "@/components/ui/tooltip";
 import { fetchUploadWithRetry } from "@/lib/client/upload-with-retry";
 import {
-  downloadCanvasImageAsPng,
+  downloadOriginalImage,
   getCanvasImageDownloadErrorMessage,
   type CanvasImageDownloadProgress,
 } from "@/lib/client/canvas-image-download";
@@ -2482,14 +2482,11 @@ export function ImageNode({
     [compareButtonVisualSize]
   );
   const shouldUseHighFidelityDisplayImage =
-    isSelected ||
-    isHovered ||
     isCompareMode ||
     boxCutoutMode ||
     localEditMode ||
     cropPanelOpen ||
     imageAdjustPanelOpen ||
-    fullscreenPreviewOpen ||
     isThisNodePicking;
   const displayImageWidth = useMemo(() => {
     const devicePixelRatio =
@@ -2522,15 +2519,6 @@ export function ImageNode({
       }),
     [data.src, displayImageQuality, displayImageWidth]
   );
-  const fullscreenPreviewSrc = useMemo(() => {
-    const originalUrl = resolveOriginalImageUrl(data.src || "");
-    return buildImageProxyUrl(originalUrl || data.src || "", {
-      delivery: "proxy",
-      width: 4096,
-      quality: 92,
-      format: "webp",
-    });
-  }, [data.src]);
   const displayCompareSrc = useMemo(
     () =>
       buildImageProxyUrl(compareSource, {
@@ -8235,7 +8223,6 @@ export function ImageNode({
     }
   };
 
-  // 下载图片 - 服务端统一转为 Photoshop 兼容 PNG，避免后缀和真实格式错配。
   const isDownloadingOriginalImage = Boolean(downloadProgress);
   const handleDownload = async () => {
     if (!data.src) return;
@@ -8249,24 +8236,16 @@ export function ImageNode({
     setDownloadProgress({
       phase: "preparing",
       message: "正在准备原图...",
-      percent: 5,
     });
 
     try {
-      await downloadCanvasImageAsPng({
-        url: data.src,
+      await downloadOriginalImage({
+        url: resolveOriginalImageUrl(data.src) || data.src,
         name: displayTitle,
-        candidates: [
-          displayImageSrc,
-          fullscreenPreviewSrc,
-          buildImageProxyUrl(resolveOriginalImageUrl(data.src) || data.src, {
-            delivery: "proxy",
-          }),
-        ],
         signal: controller.signal,
         onProgress: setDownloadProgress,
       });
-      toast.success("原图已开始下载");
+      toast.success("已开始下载");
     } catch (error) {
       if (controller.signal.aborted) {
         toast.message("已取消下载");

lib/ai/providers/vip98k.ts

@@ -99,6 +99,7 @@ const DEFAULT_POLL_INTERVAL_SECONDS = 8;
 const DEFAULT_MAX_POLL_SECONDS = 600;
 const REFERENCE_DOWNLOAD_ATTEMPTS = 3;
 const REFERENCE_DOWNLOAD_TIMEOUT_MS = 120_000;
+const REFERENCE_CDN_TIMEOUT_MS = 10_000;
 const REFERENCE_CACHE_LOOKUP_TIMEOUT_MS = 15_000;
 const MAX_REFERENCE_DOWNLOAD_BYTES = IMAGE_UPLOAD_MAX_BYTES;
 const REFERENCE_STAGING_CACHE_MS = 60_000;
@@ -682,25 +683,26 @@ async function findStagedReference(
   }
 }
 
-async function downloadReferenceImage(mediaUrl: string) {
-  let lastError: unknown;
-  for (let attempt = 1; attempt <= REFERENCE_DOWNLOAD_ATTEMPTS; attempt += 1) {
-    try {
+async function fetchReferenceImage(mediaUrl: string, preferCdn = false) {
   const response = await fetch(mediaUrl, {
-        cache: "no-store",
-        redirect: "follow",
+    cache: preferCdn ? "default" : "no-store",
+    redirect: preferCdn ? "error" : "follow",
     headers: { "User-Agent": "yedir-ai-vip98k-staging/1.0" },
-        signal: AbortSignal.timeout(REFERENCE_DOWNLOAD_TIMEOUT_MS),
+    signal: AbortSignal.timeout(preferCdn ? REFERENCE_CDN_TIMEOUT_MS : REFERENCE_DOWNLOAD_TIMEOUT_MS),
   });
-      if (!response.ok) {
+  if (!response.ok || (preferCdn && response.status !== 200)) {
+    await response.body?.cancel();
     throw new Error(`source returned HTTP ${response.status}`);
   }
 
+  const mimeType = response.headers.get("content-type") || "image/png";
+  if (preferCdn && !/^image\//i.test(mimeType) && !/^application\/octet-stream\b/i.test(mimeType)) {
+    await response.body?.cancel();
+    throw new Error("CDN response was not an image");
+  }
   const declaredLength = Number(response.headers.get("content-length"));
-      if (
-        Number.isFinite(declaredLength) &&
-        declaredLength > MAX_REFERENCE_DOWNLOAD_BYTES
-      ) {
+  if (declaredLength > MAX_REFERENCE_DOWNLOAD_BYTES) {
+    await response.body?.cancel();
     throw new Vip98kReferenceTooLargeError();
   }
 
@@ -708,17 +710,17 @@ async function downloadReferenceImage(mediaUrl: string) {
   if (buffer.byteLength > MAX_REFERENCE_DOWNLOAD_BYTES) {
     throw new Vip98kReferenceTooLargeError();
   }
-      if (
-        Number.isFinite(declaredLength) &&
-        declaredLength > 0 &&
-        buffer.byteLength !== declaredLength
-      ) {
+  if ((declaredLength > 0 && buffer.byteLength !== declaredLength) || (preferCdn && !buffer.byteLength)) {
     throw new Error("source image download was incomplete");
   }
-      return {
-        buffer,
-        mimeType: response.headers.get("content-type") || "image/png",
-      };
+  return { buffer, mimeType };
+}
+
+async function downloadReferenceImage(mediaUrl: string) {
+  let lastError: unknown;
+  for (let attempt = 1; attempt <= REFERENCE_DOWNLOAD_ATTEMPTS; attempt += 1) {
+    try {
+      return await fetchReferenceImage(mediaUrl);
     } catch (error) {
       lastError = error;
       if (error instanceof Vip98kReferenceTooLargeError) throw error;
@@ -738,6 +740,22 @@ async function downloadReferenceImage(mediaUrl: string) {
   );
 }
 
+async function downloadReferenceImageFromCdn(mediaUrl: string, stagingConfig: ReferenceStagingConfig) {
+  if (stagingConfig.storageConfig.provider !== "qiniu-kodo") return null;
+  const cdnUrl = process.env.NEXT_PUBLIC_CANVAS_CDN_ORIGIN || "";
+  if (!URL.canParse(cdnUrl) || !getStorageObjectKeyFromPublicUrl(mediaUrl, stagingConfig.sourcePublicUrl)) return null;
+  const source = new URL(mediaUrl);
+  if (source.origin !== new URL(cdnUrl).origin || source.search || source.username || source.password) return null;
+
+  try {
+    return await fetchReferenceImage(mediaUrl, true);
+  } catch (error) {
+    if (error instanceof Vip98kReferenceTooLargeError) throw error;
+    logger.warn("reference CDN download failed; trying source storage", { sourceHost: source.hostname });
+    return null;
+  }
+}
+
 async function downloadReferenceImageFromStorage(
   mediaUrl: string,
   stagingConfig: ReferenceStagingConfig,
@@ -852,9 +870,10 @@ async function stageReferenceImage(
   }
 
   const downloadStartedAt = Date.now();
+  const cdn = await downloadReferenceImageFromCdn(mediaUrl, stagingConfig);
+  const storage = cdn ? null : await downloadReferenceImageFromStorage(mediaUrl, stagingConfig);
   const downloaded =
-    (await downloadReferenceImageFromStorage(mediaUrl, stagingConfig)) ||
-    (await downloadReferenceImage(mediaUrl));
+    cdn || storage || (await downloadReferenceImage(mediaUrl));
   const downloadMs = Date.now() - downloadStartedAt;
   const normalizeStartedAt = Date.now();
   const normalized = await normalizeReferenceImage(
@@ -872,6 +891,7 @@ async function stageReferenceImage(
   cacheStagedReference(cacheKey, uploadedUrl, runtimeConfig);
   logger.info("reference image staged", {
     sourceHost: getUrlHost(mediaUrl),
+    sourceDelivery: cdn ? "cdn" : storage ? "storage" : "public-url",
     targetHost: getUrlHost(uploadedUrl),
     sourceBytes: downloaded.buffer.byteLength,
     stagedBytes: normalized.buffer.byteLength,

lib/canvas/generate-image.ts

@@ -3444,11 +3444,13 @@ async function applyLocalEditCompositeToImages(params: {
     const [originalUpload, thumbnailUpload] = await Promise.all([
       uploadFile(
         `canvas-local-edit-composited-${suffix}.png`,
-        bufferToArrayBuffer(mergedBuffer)
+        bufferToArrayBuffer(mergedBuffer),
+        { preferQiniuForm: true }
       ),
       uploadFile(
         `canvas-local-edit-composited-thumb-${suffix}.png`,
-        bufferToArrayBuffer(thumbnailBuffer)
+        bufferToArrayBuffer(thumbnailBuffer),
+        { preferQiniuForm: true }
       ),
     ]);
     mergedImages.push({

lib/canvas/photoshop-safe-download.ts

@@ -221,7 +221,9 @@ export async function convertImageToPhotoshopPng(bytes: Buffer): Promise<Buffer>
     || (metadata.space === "rgb16" && metadata.depth === "ushort");
   if (metadata.format === "png" && rgb
       && !metadata.isPalette && (metadata.pages || 1) === 1 && (!metadata.orientation || metadata.orientation === 1)) return bytes;
-  return image.rotate().toColorspace("srgb").png({ compressionLevel: 3, adaptiveFiltering: true }).toBuffer();
+  const output = image.rotate().toColorspace("srgb");
+  if (metadata.icc) output.withIccProfile("srgb");
+  return output.png({ compressionLevel: 3, adaptiveFiltering: true }).toBuffer();
 }
 
 function buildCanvasAssetFilename(params: {

lib/client/canvas-image-download.ts

@@ -1,8 +1,9 @@
 import { buildImageProxyUrl, getImageDownloadExtension } from "@/lib/image-delivery";
 import { inferOriginalImageUrl } from "@/lib/image-url";
 import { formatDownloadFailure, getDownloadFailure, type DownloadFailure } from "@/lib/canvas/download-error";
+import { withActivePageDownload } from "@/lib/client/page-refresh";
 
-export type CanvasImageDownloadPhase = "preparing" | "downloading" | "saving";
+export type CanvasImageDownloadPhase = "preparing" | "converting" | "downloading" | "saving";
 
 export type CanvasImageDownloadProgress = {
   phase: CanvasImageDownloadPhase;
@@ -189,8 +190,15 @@ function triggerCdnDownload(result: { downloadUrl: string; filename: string; byt
   return { filename: result.filename, bytes: result.bytes || 0 };
 }
 
-/** Keep the source format and bytes for chat, gallery and reference downloads. */
-export async function downloadOriginalImage({ url, name, signal, onProgress }: DownloadCanvasImageParams): Promise<CanvasImageDownloadResult> {
+const PHOTOSHOP_DOWNLOAD_EXTENSIONS = new Set(["jpg", "png", "gif", "bmp", "tiff"]);
+
+/** Preserve compatible originals and prepare a PNG for other stored images. */
+export function downloadOriginalImage(params: DownloadCanvasImageParams): Promise<CanvasImageDownloadResult> {
+  return withActivePageDownload(() => downloadOriginalImageFile(params));
+}
+
+async function downloadOriginalImageFile(params: DownloadCanvasImageParams): Promise<CanvasImageDownloadResult> {
+  const { url, name, signal, onProgress } = params;
   const source = String(url || "").trim();
   if (!source) throw new Error("图片地址无效");
   const proxy = buildImageProxyUrl(source, { delivery: "original" });
@@ -218,6 +226,11 @@ export async function downloadOriginalImage({ url, name, signal, onProgress }: D
     const metadata = await checkedFetch(target.pathname + target.search);
     const delivery = await metadata.json();
     if (delivery.delivery === "cdn") {
+      // The resolver names the attachment using the stored MIME type.
+      const extension = delivery.filename.split(".").pop();
+      if (!PHOTOSHOP_DOWNLOAD_EXTENSIONS.has(extension)) {
+        return downloadPngFile(params, "converting");
+      }
       const result = triggerCdnDownload(delivery, signal);
       onProgress?.({ phase: "downloading", message: "已开始下载，可在浏览器下载列表查看进度" });
       return result;
@@ -225,9 +238,16 @@ export async function downloadOriginalImage({ url, name, signal, onProgress }: D
     if (delivery.delivery !== "proxy") throw new Error("下载链接无效");
   }
   const response = await checkedFetch(proxy);
+  const contentType = response.headers.get("content-type") || "";
+  if (!contentType.toLowerCase().startsWith("image/")) throw new Error("Source is not an image");
+  const extension = getImageDownloadExtension(contentType);
+  // A local blob can still be downloaded while its upload is in progress.
+  if (/^https?:$/.test(target.protocol) && !PHOTOSHOP_DOWNLOAD_EXTENSIONS.has(extension)) {
+    void response.body?.cancel().catch(() => {});
+    return downloadPngFile(params, "converting");
+  }
   const blob = await readResponseBlobWithProgress(response, onProgress);
-  if (!blob.type.toLowerCase().startsWith("image/")) throw new Error("Source is not an image");
-  const extension = getImageDownloadExtension(blob.type);
+  signal?.throwIfAborted();
   const filename = extension ? `${filenameBase}.${extension}` : filenameBase;
   triggerBlobDownload(blob, filename);
   return { filename, bytes: blob.size };
@@ -252,14 +272,15 @@ function toDownloadCandidates(url: string, candidates: string[] = []) {
 
 async function readResponseBlobWithProgress(
   response: Response,
-  onProgress?: (progress: CanvasImageDownloadProgress) => void
+  onProgress?: (progress: CanvasImageDownloadProgress) => void,
+  message = "正在下载原图..."
 ) {
   const totalBytes = Number(response.headers.get("content-length") || 0);
   if (!response.body) {
     const blob = await response.blob();
     onProgress?.({
       phase: "downloading",
-      message: "正在下载原图...",
+      message,
       loadedBytes: blob.size,
       totalBytes: totalBytes || blob.size,
       percent: 100,
@@ -279,7 +300,7 @@ async function readResponseBlobWithProgress(
     loadedBytes += value.byteLength;
     onProgress?.({
       phase: "downloading",
-      message: "正在下载原图...",
+      message,
       loadedBytes,
       totalBytes: totalBytes || undefined,
       percent: totalBytes > 0 ? Math.min(99, Math.round((loadedBytes / totalBytes) * 100)) : undefined,
@@ -291,13 +312,17 @@ async function readResponseBlobWithProgress(
   });
 }
 
-export async function downloadCanvasImageAsPng({
+export function downloadCanvasImageAsPng(params: DownloadCanvasImageParams): Promise<CanvasImageDownloadResult> {
+  return withActivePageDownload(() => downloadPngFile(params, "preparing"));
+}
+
+async function downloadPngFile({
   candidates,
   name,
   onProgress,
   signal,
   url,
-}: DownloadCanvasImageParams): Promise<CanvasImageDownloadResult> {
+}: DownloadCanvasImageParams, preparationPhase: "preparing" | "converting"): Promise<CanvasImageDownloadResult> {
   const raw = String(url || "").trim();
   if (!raw) {
     throw new Error("图片地址无效");
@@ -310,11 +335,9 @@ export async function downloadCanvasImageAsPng({
     "canvas-image"
   );
 
-  onProgress?.({
-    phase: "preparing",
-    message: "正在准备原图...",
-    percent: 8,
-  });
+  const isConverting = preparationPhase === "converting";
+  const conversionMessage = "正在转换为兼容 PNG，完成后自动下载";
+  onProgress?.({ phase: preparationPhase, message: isConverting ? conversionMessage : "正在准备原图..." });
 
   let response: Response | null = null;
   let errorPayload: DownloadErrorPayload | null = null;
@@ -353,7 +376,10 @@ export async function downloadCanvasImageAsPng({
       if (Date.now() >= preparationDeadline || preparationPolls >= 60) {
         throw new CanvasImageDownloadError("原图仍在准备中", { code: "preparation_timeout", status: 202, requestId: preparing.requestId });
       }
-      onProgress?.({ phase: "preparing", message: preparing.message || "正在准备原图，完成后将自动下载" });
+      onProgress?.({
+        phase: preparationPhase,
+        message: isConverting ? conversionMessage : preparing.message || "正在准备原图，完成后将自动下载",
+      });
       const delaySeconds = Math.max(preparationPolls > 5 ? 5 : 1, Math.min(5, Number(preparing.retryAfter) || 3));
       await waitForRetry(delaySeconds * 1000, signal);
       continue;
@@ -384,7 +410,6 @@ export async function downloadCanvasImageAsPng({
         retryAfterSeconds > 0
           ? `请求较多，${retryAfterSeconds} 秒后自动重试...`
           : "请求较多，正在自动重试...",
-      percent: 8,
     });
     await waitForRetry(retryAfterSeconds * 1000, signal);
   }
@@ -413,7 +438,9 @@ export async function downloadCanvasImageAsPng({
   const filename =
     parseAttachmentFilename(response.headers.get("content-disposition")) ||
     `${filenameBase}.png`;
-  const blob = await readResponseBlobWithProgress(response, onProgress);
+  const downloadMessage = isConverting ? "正在下载 PNG..." : "正在下载原图...";
+  onProgress?.({ phase: "downloading", message: downloadMessage });
+  const blob = await readResponseBlobWithProgress(response, onProgress, downloadMessage);
 
   onProgress?.({
     phase: "saving",

lib/client/page-refresh.ts

@@ -1,10 +1,44 @@
 export const BEFORE_PAGE_REFRESH = "app:before-page-refresh";
+export const PAGE_DOWNLOAD_ACTIVE_ATTRIBUTE = "data-page-download-active";
 export type PageRefreshRequest = {
   save: (action: () => Promise<void>) => void;
   block: (message: string) => void;
 };
 
+const downloadListeners = new Set<() => void>();
+let activePageDownloads = 0;
+
+export function isPageDownloadActive() {
+  return activePageDownloads > 0;
+}
+
+export function subscribeToPageDownloadActivity(listener: () => void) {
+  downloadListeners.add(listener);
+  return () => { downloadListeners.delete(listener); };
+}
+
+function publishDownloadActivity() {
+  if (typeof document !== "undefined") {
+    document.documentElement?.toggleAttribute(PAGE_DOWNLOAD_ACTIVE_ATTRIBUTE, isPageDownloadActive());
+  }
+  for (const listener of downloadListeners) listener();
+}
+
+export async function withActivePageDownload<T>(download: () => Promise<T>): Promise<T> {
+  if (++activePageDownloads === 1) publishDownloadActivity();
+  try {
+    return await download();
+  } finally {
+    if (--activePageDownloads === 0) publishDownloadActivity();
+  }
+}
+
+function assertPageDownloadFinished() {
+  if (isPageDownloadActive()) throw new Error("文件正在下载，请等下载完成后再刷新。");
+}
+
 export async function preparePageRefresh() {
+  assertPageDownloadFinished();
   const actions: Array<() => Promise<void>> = [];
   let blocked = "";
   window.dispatchEvent(new CustomEvent<PageRefreshRequest>(BEFORE_PAGE_REFRESH, {
@@ -12,4 +46,5 @@ export async function preparePageRefresh() {
   }));
   if (blocked) throw new Error(blocked);
   for (const action of actions) await action();
+  assertPageDownloadFinished();
 }

lib/image-delivery.ts

@@ -1,6 +1,15 @@
 import { normalizeLegacyAliyunStorageUrl } from "./storage/retired-storage";
 
 const IMAGE_PROXY_PATH = "/api/image-proxy";
+const CDN_PREVIEW_WIDTHS = [64, 160, 192, 240, 320, 360, 480, 520, 640, 720, 840, 960, 1280, 1600, 2048, 2560, 2600, 3200, 4096];
+
+function getConfiguredCdnUrl(): URL | undefined {
+  try {
+    return new URL(process.env.NEXT_PUBLIC_CANVAS_CDN_ORIGIN || "");
+  } catch {
+    return undefined;
+  }
+}
 
 /** Error fallbacks must keep unavailable legacy sources behind archive resolution. */
 export function buildImageFallbackUrl(value: string | null | undefined): string {
@@ -102,10 +111,7 @@ export function isAlibabaModelImageUrl(value: string): boolean {
 
 function isTrustedDirectStorageImageHost(hostname: string): boolean {
   const normalized = hostname.trim().toLowerCase();
-  let configuredCdnHost = "";
-  try { configuredCdnHost = new URL(process.env.NEXT_PUBLIC_CANVAS_CDN_ORIGIN || "").hostname; } catch { /* optional */ }
   return (
-    (configuredCdnHost !== "" && normalized === configuredCdnHost) ||
     normalized === "yybb.top" ||
     normalized.endsWith(".qiniucs.com") ||
     normalized.endsWith(".qiniudn.com") ||
@@ -127,20 +133,29 @@ function resolveTrustedDirectStorageDisplayUrl(
 ): string | null {
   try {
     const target = new URL(url);
+    const configuredCdn = getConfiguredCdnUrl();
+    const isConfiguredCdn = target.origin === configuredCdn?.origin;
     if (
+      target.hostname !== configuredCdn?.hostname &&
       !isTrustedDirectStorageImageHost(target.hostname) &&
       !isFirstPartyQiniuAsset(target)
     ) {
       return null;
     }
 
-    const width = normalizeWidth(options.width);
-    const quality = normalizeQuality(options.quality);
+    const requestedWidth = normalizeWidth(options.width);
+    let width = requestedWidth;
+    let quality = normalizeQuality(options.quality);
     const format = options.format;
     if ((!width && !quality && !format) || target.search) {
       return target.toString();
     }
 
+    if (isConfiguredCdn && format === "webp" && requestedWidth) {
+      width = CDN_PREVIEW_WIDTHS.find((size) => size >= requestedWidth) ?? requestedWidth;
+      if (quality && quality >= 84 && quality <= 92) quality = 88;
+    }
+
     const operations = ["imageView2", "2"];
     if (width) operations.push("w", String(width));
     if (format) operations.push("format", format === "jpeg" ? "jpg" : format);

lib/jobs/image-archive-job.ts

@@ -26,14 +26,14 @@ function getBatchSize() {
   return Math.max(1, Math.min(50, Math.round(parsed)));
 }
 
-export async function runImageArchiveJob() {
+export async function runImageArchiveJob({ preferredTaskId }: { preferredTaskId?: string } = {}) {
   return trackRuntimeWork(async () => {
   const batchSize = getBatchSize();
   console.log(`[ImageArchiveJob] Start image archive job (batchSize=${batchSize})`);
 
   await recoverStaleImageArchiveTasks();
   scheduleImageDownloadPreparation();
-  const storeTasks = await getImageArchiveTasksToStore({ limit: batchSize });
+  const storeTasks = await getImageArchiveTasksToStore({ limit: batchSize, preferredTaskId });
   let storeSucceeded = 0;
   let storeFailed = 0;
 

lib/storage/image-archive-db.ts

@@ -98,8 +98,11 @@ export async function enqueueImageArchiveTasks(params: {
   return tasks;
 }
 
-export async function getImageArchiveTasksToStore(params: { limit: number }) {
+export async function getImageArchiveTasksToStore(params: { limit: number; preferredTaskId?: string }) {
   const now = new Date();
+  const priority = params.preferredTaskId
+    ? [asc(sql`case when ${imageArchiveTask.id} = ${params.preferredTaskId} then 0 else 1 end`)]
+    : [];
   return await db
     .select()
     .from(imageArchiveTask)
@@ -110,7 +113,7 @@ export async function getImageArchiveTasksToStore(params: { limit: number }) {
         lt(imageArchiveTask.attemptCount, MAX_IMAGE_ARCHIVE_ATTEMPTS),
       ),
     )
-    .orderBy(asc(imageArchiveTask.createdAt), asc(imageArchiveTask.id))
+    .orderBy(...priority, asc(imageArchiveTask.createdAt), asc(imageArchiveTask.id))
     .limit(Math.max(1, Math.min(50, params.limit)));
 }
 

lib/storage/image-archive-worker.ts

@@ -6,6 +6,7 @@ type Worker = {
   running: boolean;
   scheduled: boolean;
   requested: boolean;
+  preferredTaskId?: string;
   retryTimer?: ReturnType<typeof setTimeout>;
 };
 function getWorker(): Worker {
@@ -13,8 +14,9 @@ function getWorker(): Worker {
   return (root[workerKey] ??= { running: false, scheduled: false, requested: false });
 }
 
-export function scheduleImageArchiveWorker(deliveryConfirmed = false) {
+export function scheduleImageArchiveWorker(deliveryConfirmed = false, preferredTaskId?: string) {
   const worker = getWorker();
+  worker.preferredTaskId ??= preferredTaskId;
   worker.requested = true;
   if (worker.running || (worker.scheduled && !deliveryConfirmed)) return;
   worker.scheduled = true;
@@ -31,7 +33,9 @@ export function scheduleImageArchiveWorker(deliveryConfirmed = false) {
       const { runImageArchiveJob } = await import("@/lib/jobs/image-archive-job");
       do {
         worker.requested = false;
-        const result = await runImageArchiveJob();
+        const nextTaskId = worker.preferredTaskId;
+        worker.preferredTaskId = undefined;
+        const result = await runImageArchiveJob({ preferredTaskId: nextTaskId });
         retryNeeded = result.stats.pendingStore > 0 || result.stats.pendingReplace > 0 || result.pendingDownloads === true;
         // Stop when only backoff tasks remain; do not spin while storage is down.
         if (!worker.requested && result.store.total === 0 && result.replace.total === 0 && result.downloadTasks === 0) break;

lib/storage/original-image-download.ts

@@ -4,6 +4,7 @@ import { findImageArchiveDownloadTask } from "./image-archive-db";
 import { inferOriginalImageUrl } from "@/lib/image-url";
 import { getImageDownloadExtension } from "@/lib/image-delivery";
 import { sanitizeCanvasDownloadFileName } from "@/lib/canvas/photoshop-safe-download";
+import { HeadObjectCommand } from "@aws-sdk/client-s3";
 
 /** Resolve the archived original without waiting for a separate PNG conversion. */
 export async function resolveOriginalCdnDownload(source: string, name: string, signal: AbortSignal) {
@@ -14,6 +15,10 @@ export async function resolveOriginalCdnDownload(source: string, name: string, s
   let target = new URL(source);
   if (target.origin !== base.origin && (!origin || target.origin !== new URL(origin).origin)) {
     const task = await findImageArchiveDownloadTask([...new Set([source, inferOriginalImageUrl(source)])]);
+    if (task?.status === "pending" && !task.targetUrl) {
+      const { scheduleImageArchiveWorker } = await import("./image-archive-worker");
+      scheduleImageArchiveWorker(false, task.id);
+    }
     target = new URL(task?.targetUrl || source);
   }
   if (origin && target.origin === new URL(origin).origin && !target.searchParams.has("token")) {
@@ -28,8 +33,32 @@ export async function resolveOriginalCdnDownload(source: string, name: string, s
   // Only metadata crosses the application server. The browser receives the file
   // from the CDN, including when cross-origin fetch is disabled by storage CORS.
   const response = await fetch(target, {
-    method: "HEAD", cache: "no-store",
-    signal: AbortSignal.any([signal, AbortSignal.timeout(10_000)]),
+    method: "HEAD", cache: "default",
+    signal: AbortSignal.any([signal, AbortSignal.timeout(3_000)]),
+  }).catch(async (error) => {
+    signal.throwIfAborted();
+    if (target.search) throw error;
+    const { createS3Client, toDbS3UploadConfig } = await import("./service");
+    const storage = toDbS3UploadConfig(config);
+    if (!storage) throw error;
+    const key = decodeURIComponent(target.pathname.slice(base.pathname.replace(/\/$/, "").length + 1));
+    if (!key) throw error;
+    const client = createS3Client(storage);
+    try {
+      const object = await client.send(new HeadObjectCommand({ Bucket: storage.bucket, Key: key }), {
+        abortSignal: AbortSignal.any([signal, AbortSignal.timeout(5_000)]),
+      });
+      return new Response(null, { headers: {
+        "content-type": object.ContentType || "",
+        "content-length": String(object.ContentLength ?? 0),
+      } });
+    } catch (storageError) {
+      const status = (storageError as { $metadata?: { httpStatusCode?: number } })?.$metadata?.httpStatusCode;
+      if (status === 403 || status === 404) throw new Error(`HTTP ${status}`);
+      throw error;
+    } finally {
+      client.destroy();
+    }
   });
   if (!response.ok) throw new Error(`HTTP ${response.status}`);
   const contentType = response.headers.get("content-type") || "";

lib/storage/service.ts

@@ -3,6 +3,7 @@ import { isRetiredStorageUrl, isLegacyAliyunStorageConfig, RETIRED_STORAGE_MESSA
 
 import { DeleteObjectCommand, PutObjectCommand, S3Client } from "@aws-sdk/client-s3";
 import { put } from "@vercel/blob";
+import { createHmac } from "node:crypto";
 import {
   getDefaultStorageConfig,
   getStorageConfigById,
@@ -239,12 +240,48 @@ export async function maybeEnqueueStorageMigrationTask(params: {
   await maybeEnqueueAliyunMigrationTask(params);
 }
 
+async function uploadQiniuForm(
+  config: S3UploadConfig,
+  key: string,
+  buffer: ArrayBuffer,
+  contentType: string
+) {
+  const encode = (value: Buffer) =>
+    value.toString("base64").replace(/\+/g, "-").replace(/\//g, "_");
+  const policy = encode(Buffer.from(JSON.stringify({
+    scope: `${config.bucket}:${key}`,
+    deadline: Math.floor(Date.now() / 1000) + 120,
+    insertOnly: 1,
+  })));
+  const signature = encode(createHmac("sha1", config.secretAccessKey).update(policy).digest());
+  const form = new FormData();
+  form.append("token", `${config.accessKeyId}:${signature}:${policy}`);
+  form.append("key", key);
+  form.append("file", new Blob([buffer], { type: contentType }), key.split("/").at(-1));
+
+  const startedAt = Date.now();
+  const response = await fetch("https://upload.qiniup.com/", {
+    method: "POST",
+    body: form,
+    redirect: "error",
+    signal: AbortSignal.timeout(45_000),
+  });
+  if (!response.ok) {
+    await response.body?.cancel();
+    throw new Error(`Qiniu form upload returned HTTP ${response.status}`);
+  }
+  const result = await response.json() as { key?: string };
+  if (result.key !== key) throw new Error("Qiniu form upload returned an unexpected key");
+  logger.info("qiniu_form_upload_completed", { bytes: buffer.byteLength, elapsedMs: Date.now() - startedAt });
+}
+
 // S3/MinIO 上传函数（使用 AWS SDK）
 async function uploadToS3(
   filename: string,
   buffer: ArrayBuffer,
   config: S3UploadConfig,
-  s3Client = createS3Client(config)
+  s3Client = createS3Client(config),
+  preferQiniuForm = false
 ) {
   const {
     endpoint,
@@ -260,6 +297,14 @@ async function uploadToS3(
   const contentType = getContentType(filename);
 
   try {
+    if (preferQiniuForm && config.provider === "qiniu-kodo" && config.region === "cn-east-1") {
+      try {
+        await uploadQiniuForm(config, key, buffer, contentType);
+        return { url: buildS3PublicUrl(config, key), pathname: key, contentType };
+      } catch (error) {
+        logger.warn("[Upload] Qiniu form upload failed, retrying the same object through S3", error);
+      }
+    }
     logger.debug(`[S3 Upload] Uploading to: ${normalizedEndpoint}/${bucket}/${key}`);
 
     // 上传文件
@@ -551,7 +596,8 @@ async function uploadWithAnyEnabledStorageConfig(
 // 上传文件到存储服务
 export async function uploadFile(
   filename: string,
-  buffer: ArrayBuffer
+  buffer: ArrayBuffer,
+  options?: { preferQiniuForm?: boolean }
 ): Promise<UploadedFileResult> {
   logger.debug(`[Upload] Starting upload for file: ${filename}`);
 
@@ -572,7 +618,7 @@ export async function uploadFile(
       logger.debug(`[Upload] Using database S3 config: ${selectedStorageConfig?.name}`);
       logger.debug(`[Upload] Endpoint: ${dbS3Config.endpoint}`);
       logger.debug(`[Upload] Bucket: ${dbS3Config.bucket}`);
-      const uploaded = await uploadToS3(filename, buffer, dbS3Config);
+      const uploaded = await uploadToS3(filename, buffer, dbS3Config, undefined, options?.preferQiniuForm);
       lastKnownGoodDbS3Config = dbS3Config;
       await maybeEnqueueAliyunMigrationTask({
         uploaded,

tests/routes/canvas-download-speed.test.ts

@@ -112,6 +112,10 @@ test("compatible PNG remains byte-identical; JPEG becomes RGB PNG without resizi
   const converted = await module.convertImageToPhotoshopPng(jpeg);
   const metadata = await sharp(converted).metadata();
   expect(metadata).toMatchObject({ format: "png", space: "srgb", width: 32, height: 48, depth: "uchar" });
+  const webp = await sharp(bytes).withIccProfile("p3").webp().toBuffer();
+  const webpPng = await module.convertImageToPhotoshopPng(webp);
+  const webpPngMetadata = await sharp(webpPng).metadata();
+  expect(webpPngMetadata).toMatchObject({ format: "png", width: 32, height: 48, hasAlpha: true, hasProfile: true });
 });
 test("CDN delivery requires a ready compatible asset and a configured HTTPS storage origin", async () => {
   let url = "https://cdn.example/uploads/test.png";

tests/routes/image-archive-flow.test.ts

@@ -242,7 +242,7 @@ test("inline outputs have short, stable preview identities and durable queue pay
 
 test("background storage starts after delivery and coalesces repeated wakeups", async () => {
   const callbacks: Array<() => Promise<void>> = [];
-  let runs = 0;
+  const preferences: Array<string | undefined> = [];
   const module = serverLoader({
     "next/server": {
       after: (fn: () => Promise<void>) => {
@@ -250,10 +250,10 @@ test("background storage starts after delivery and coalesces repeated wakeups",
       },
     },
     "@/lib/jobs/image-archive-job": {
-      runImageArchiveJob: async () => {
-        runs += 1;
+      runImageArchiveJob: async ({ preferredTaskId }: { preferredTaskId?: string }) => {
+        preferences.push(preferredTaskId);
         return {
-          store: { total: runs === 1 ? 1 : 0 },
+          store: { total: preferences.length === 1 ? 1 : 0 },
           replace: { total: 0 },
           stats: { pendingStore: 0, pendingReplace: 0 },
           downloadTasks: 0,
@@ -262,11 +262,11 @@ test("background storage starts after delivery and coalesces repeated wakeups",
     },
   })("lib/storage/image-archive-worker.ts");
   module.scheduleImageArchiveWorker();
-  module.scheduleImageArchiveWorker();
+  module.scheduleImageArchiveWorker(false, "requested-image");
   expect(callbacks).toHaveLength(1);
-  expect(runs).toBe(0);
+  expect(preferences).toEqual([]);
   await callbacks[0]();
-  expect(runs).toBe(2);
+  expect(preferences).toEqual(["requested-image", undefined]);
 });
 
 test("bucket failure retains the provider URL and retry task", async () => {

tests/routes/image-delivery-qiniu.test.ts

@@ -7,6 +7,177 @@ import { serverLoader } from "../helpers/canvas-download-server-loader";
 import { NextResponse } from "next/server";
 
 test.describe("Qiniu image delivery", () => {
+  test("coalesces nearby configured CDN preview sizes and quality while preserving original URLs", () => {
+    const source = "https://cdn.example/uploads/sample.png";
+    const { buildImageProxyUrl: build } = serverLoader({}, {
+      NEXT_PUBLIC_CANVAS_CDN_ORIGIN: "https://cdn.example",
+    })("lib/image-delivery.ts");
+    expect(build(source, { width: 329, quality: 86, format: "webp" })).toBe(
+      `${source}?imageView2/2/w/360/format/webp/q/88`,
+    );
+    expect(build(source, { width: 331, quality: 92, format: "webp" })).toBe(
+      build(source, { width: 360, quality: 88, format: "webp" }),
+    );
+    expect(build(source, { width: 640, quality: 76, format: "webp" })).toContain("w/640/format/webp/q/76");
+    expect(build(source, { width: 960, quality: 92, format: "webp" })).toContain("w/960/format/webp/q/88");
+    expect(build(`${source}?token=signed`, { width: 331, format: "webp" })).toBe(`${source}?token=signed`);
+    expect(build(source)).toBe(source);
+    expect(new URL(build(source, { delivery: "original" }), "https://app.example").searchParams.get("url")).toBe(source);
+    expect(build("https://yybb.top/uploads/sample.png", { width: 331, quality: 92, format: "webp" })).toContain("w/331/format/webp/q/92");
+  });
+
+  for (const mode of ["cdn", "storage", "signed"] as const) {
+    test(`98K reference staging reads complete image bytes via ${mode}`, async () => {
+      const original = await sharp({ create: { width: 64, height: 64, channels: 3, background: "#a45623" } }).png().toBuffer();
+      const cdn = "https://cdn.example";
+      const source = `${cdn}/media/uploads/reference.png${mode === "signed" ? "?token=signed" : ""}`;
+      const calls: string[] = [];
+      const command = (operation: string) => class {
+        operation = operation;
+        constructor(public input: { Key: string; Body?: Buffer }) {}
+      };
+      const config = { provider: "qiniu-kodo", bucket: "images", publicUrl: `${cdn}/media` };
+      const load = serverLoader({
+        "./vip98k-chat": {},
+        "@/lib/db/queries": { getDefaultStorageConfig: async () => config, getSystemSetting: async () => null },
+        "@/lib/storage/image-archive": {},
+        "@aws-sdk/client-s3": {
+          GetObjectCommand: command("get"), HeadObjectCommand: command("head"), PutObjectCommand: command("put"),
+        },
+        "@/lib/storage/service": {
+          toDbS3UploadConfig: () => config,
+          buildS3PublicUrl: (_: unknown, key: string) => `${config.publicUrl}/${key}`,
+          createS3Client: () => ({ send: async ({ operation, input }: { operation: string; input: { Key: string; Body: Buffer } }) => {
+            calls.push(operation);
+            if (operation === "head") return {};
+            if (operation === "get") {
+              expect(input.Key).toBe("uploads/reference.png");
+              return { Body: { transformToByteArray: async () => original }, ContentLength: original.length };
+            }
+            expect((await sharp(input.Body).metadata()).format).toBe("jpeg");
+            return {};
+          } }),
+        },
+        "@/lib/observability/logger": { createLogger: () => ({ debug() {}, info() {}, warn() {}, error() {} }) },
+        fetch: async (url: string, init: RequestInit) => {
+          if (url === source) {
+            calls.push("cdn");
+            expect(init.redirect).toBe("error");
+            return mode === "cdn"
+              ? new Response(original, { headers: { "content-type": "image/png", "content-length": String(original.length) } })
+              : new Response(original.subarray(0, 4), { headers: { "content-type": "image/png", "content-length": String(original.length) } });
+          }
+          calls.push("submit");
+          expect(String(init.body)).toContain("vip98k-cache-v2");
+          return Response.json({ taskId: "test-task", task_id: "test-task" });
+        },
+      }, { NEXT_PUBLIC_CANVAS_CDN_ORIGIN: cdn });
+      const { submitVip98kExternalTask } = load("lib/ai/providers/vip98k.ts");
+      await submitVip98kExternalTask({ apiKey: "test", modelId: "google/nano-banana-2", kind: "image", imageUrls: [source], durable: true });
+      expect(calls).toEqual(["head", ...(mode !== "signed" ? ["cdn"] : []), ...(mode !== "cdn" ? ["get"] : []), "put", "submit"]);
+    });
+  }
+
+  for (const [source, reusesSource] of [
+    ["https://cdn.example/media/uploads/source.png", true],
+    ["https://cdn.example/media/uploads/direct/1a868070-0d5b-4c99-937d-f10d6dc59612/source.png", true],
+    ["https://cdn.example/media/uploads/source.png?token=temporary", false],
+    ["https://cdn.example/media-other/uploads/source.png", false],
+  ] as const) {
+    test(`watermark removal handles ${source} according to its storage origin and signature`, async () => {
+      const storedResult = "https://cdn.example/media/uploads/result.png";
+      const uploadedInput = "https://cdn.example/media/uploads/staged.png";
+      const transferred: string[] = [];
+      const uploaded: string[] = [];
+      const saved: string[] = [];
+      const route = serverLoader({
+        "next/server": { NextResponse: Response },
+        "@/app/(auth)/auth": { auth: async () => ({ user: { id: "user-1" } }) },
+        "@/lib/db": { db: {
+          select: () => ({ from: () => ({ where: () => ({ limit: async () => [{ value: { apiKey: "fixture" } }] }) }) }),
+          insert: () => ({ values: (row: { originalUrl: string }) => ({
+            returning: async () => { saved.push(row.originalUrl); return [{ id: "image-1" }]; },
+          }) }),
+        } },
+        "@/lib/db/schema": { systemSettings: {}, generatedImage: {} },
+        "drizzle-orm": { eq: () => null },
+        "@/lib/db/queries": {
+          getDefaultStorageConfig: async () => ({ type: "qiniu-kodo", isEnabled: true, publicUrl: "https://cdn.example/media" }),
+          getPointsSystemConfig: async () => ({}),
+          getMediaAssetsByUserAndUrls: async () => [],
+          upsertMediaAsset: async () => null,
+        },
+        "@/lib/storage/service": {
+          uploadFile: async (filename: string) => { uploaded.push(filename); return { url: uploadedInput }; },
+        },
+        "@/lib/points/feature-charge": { prepareFeaturePointsCharge: async () => ({ ok: true, chargeable: false }) },
+        "@/lib/points/config": { getImageToolCreditCost: () => 0 },
+        "@/lib/canvas/generate-image": {},
+        fetch: async (url: string, init?: RequestInit) => {
+          if (new URL(url).hostname === "techsz.aoscdn.com") {
+            if (init?.method === "POST") {
+              expect((init.body as FormData).get("url")).toBe(reusesSource ? source : uploadedInput);
+              return Response.json({ data: { task_id: "fixture-task" } });
+            }
+            return Response.json({ data: { state: 1, file: storedResult } });
+          }
+          transferred.push(url);
+          return new Response(new Uint8Array([1, 2, 3]));
+        },
+      })("app/api/watermark-remove/route.ts");
+
+      const response = await route.POST(new Request("https://app.example/api/watermark-remove", {
+        method: "POST",
+        body: JSON.stringify({ image_url: source }),
+      }));
+      expect(await response.json()).toMatchObject({ success: true, original_url: storedResult });
+      expect(transferred).toEqual(reusesSource ? [] : [source]);
+      expect(uploaded).toHaveLength(reusesSource ? 0 : 1);
+      expect(saved).toEqual([storedResult]);
+    });
+  }
+
+  for (const formWorks of [true, false]) {
+    test(`local edit storage ${formWorks ? "uses Qiniu form upload" : "reuses the same key on S3 fallback"}`, async () => {
+      const bytes = new Uint8Array([1, 2, 3]).buffer;
+      const config = {
+        id: "fixture", type: "qiniu-kodo", isEnabled: true, region: "cn-east-1",
+        endpoint: "https://s3.example", publicUrl: "https://cdn.example",
+        bucket: "images", accessKeyId: "fixture-ak", secretAccessKey: "fixture-sk",
+      };
+      let formKey = "";
+      const s3Keys: string[] = [];
+      const storage = serverLoader({
+        "@vercel/blob": {},
+        "@aws-sdk/client-s3": {
+          PutObjectCommand: class { constructor(public input: { Key: string }) {} },
+          S3Client: class {
+            async send(command: { input: { Key: string } }) { s3Keys.push(command.input.Key); }
+          },
+        },
+        "@/lib/db/queries": {
+          getDefaultStorageConfig: async () => config,
+          getSystemSetting: async () => ({ value: { enabled: false } }),
+        },
+        "@/lib/storage/migration-db": {},
+        "@/lib/observability/logger": { createLogger: () => ({ debug() {}, warn() {}, info() {}, error() {} }) },
+        fetch: async (url: string, init: RequestInit) => {
+          expect(url).toBe("https://upload.qiniup.com/");
+          const form = init.body as FormData;
+          formKey = String(form.get("key"));
+          const token = String(form.get("token"));
+          const policy = JSON.parse(Buffer.from(token.split(":")[2], "base64url").toString());
+          expect(policy).toMatchObject({ scope: `images:${formKey}`, insertOnly: 1 });
+          expect((form.get("file") as File).size).toBe(3);
+          return formWorks ? Response.json({ key: formKey }) : new Response(null, { status: 503 });
+        },
+      })("lib/storage/service.ts");
+      const saved = await storage.uploadFile("local-edit.png", bytes, { preferQiniuForm: true });
+      expect(saved).toMatchObject({ pathname: formKey, url: "https://cdn.example/" + formKey });
+      expect(s3Keys).toEqual(formWorks ? [] : [formKey]);
+    });
+  }
+
   test("model result buckets use our thumbnail endpoint without forbidden OSS transforms", () => {
     const source = "https://dashscope-a717.oss-accelerate.aliyuncs.com/output.png";
     const preview = new URL(buildImageProxyUrl(source, { width: 960, format: "webp" }), "https://app.example");

tests/routes/original-image-download.test.ts

@@ -1,5 +1,6 @@
 import { test, expect } from "@playwright/test";
 import { serverLoader } from "../helpers/canvas-download-server-loader";
+import type { CanvasImageDownloadProgress } from "@/lib/client/canvas-image-download";
 
 const config = { type: "qiniu-kodo", isEnabled: true, publicUrl: "https://cdn.example" };
 
@@ -10,7 +11,8 @@ test("original downloads use the archived JPEG rather than the prepared PNG and
     "./image-archive-db": { findImageArchiveDownloadTask: async () => ({ targetUrl: "https://cdn.example/original.jpg", metadata: {
       downloadAsset: { status: "ready", url: "https://cdn.example/converted.png", contentType: "image/png" },
     } }) },
-    fetch: async (url: URL, options: { method: string }) => {
+    fetch: async (url: URL, options: { method: string; cache: string }) => {
+      expect(options.cache).toBe("default");
       calls.push({ url: url.toString(), method: options.method });
       return { ok: true, headers: new Headers({ "content-type": "image/jpeg", "content-length": "12345" }),
         arrayBuffer() { throw new Error("Image bytes must bypass the application"); } };
@@ -52,6 +54,40 @@ test("temporary third-party URLs are never checked with HEAD when no archive is
   expect(await module.resolveOriginalCdnDownload("https://upstream.example/image.png", "image", new AbortController().signal)).toBeNull();
 });
 
+test("downloading a pending original prioritizes its existing archive task and keeps the proxy available", async () => {
+  const preferred: string[] = [];
+  const module = serverLoader({
+    "@/lib/db/queries": { getDefaultStorageConfig: async () => config },
+    "./image-archive-db": { findImageArchiveDownloadTask: async () => ({ id: "pending-image", status: "pending", targetUrl: null }) },
+    "./image-archive-worker": { scheduleImageArchiveWorker: (_delivery: boolean, id: string) => preferred.push(id) },
+    fetch() { throw new Error("The original must remain available through the proxy while it is queued"); },
+  })("lib/storage/original-image-download.ts");
+  expect(await module.resolveOriginalCdnDownload("https://upstream.example/queued.png", "image", new AbortController().signal)).toBeNull();
+  expect(preferred).toEqual(["pending-image"]);
+});
+
+test("a CDN metadata timeout falls back to the original Kodo object without reading its body", async () => {
+  let closed = false;
+  const module = serverLoader({
+    "@/lib/db/queries": { getDefaultStorageConfig: async () => config },
+    "./image-archive-db": {},
+    "./service": {
+      toDbS3UploadConfig: () => ({ bucket: "images" }),
+      createS3Client: () => ({
+        send: async (command: { input: { Bucket: string; Key: string } }) => {
+          expect(command.input).toEqual({ Bucket: "images", Key: "uploads/source.png" });
+          return { ContentType: "image/jpeg", ContentLength: 12345 };
+        },
+        destroy: () => { closed = true; },
+      }),
+    },
+    fetch: async () => { throw new DOMException("Timed out", "TimeoutError"); },
+  })("lib/storage/original-image-download.ts");
+  const result = await module.resolveOriginalCdnDownload("https://cdn.example/uploads/source.png", "图片.png", new AbortController().signal);
+  expect(result).toMatchObject({ delivery: "cdn", filename: "图片.jpg", bytes: 12345 });
+  expect(closed).toBe(true);
+});
+
 test("original download metadata reports missing sources with cause, advice and a feedback ID", async () => {
   const route = serverLoader({
     "next/server": { NextResponse: Response },
@@ -66,6 +102,30 @@ test("original download metadata reports missing sources with cause, advice and
   expect(data.error).toContain(data.requestId);
 });
 
+test("the original proxy returns the first bytes while the upstream is still sending the file", async () => {
+  const head = Uint8Array.from([255, 216, 255, 224]);
+  const tail = Uint8Array.from([4, 8, 255, 217]);
+  let upstream!: ReadableStreamDefaultController<Uint8Array>;
+  const body = new ReadableStream<Uint8Array>({
+    start(controller) { upstream = controller; controller.enqueue(head); },
+  });
+  const route = serverLoader({
+    "next/server": { NextResponse: Response },
+    fetch: async () => new Response(body, { headers: { "content-type": "image/jpeg", "content-length": "8" } }),
+  })("app/api/image-proxy/route.ts");
+  const response = await route.GET({
+    nextUrl: new URL("https://app.example/api/image-proxy?url=https%3A%2F%2Fimages.example%2Foriginal.jpg&original=1"),
+    signal: new AbortController().signal, headers: new Headers(),
+  });
+  expect(response.headers.get("content-length")).toBe("8");
+  const reader = response.body.getReader();
+  expect((await reader.read()).value).toEqual(head);
+  upstream.enqueue(tail);
+  upstream.close();
+  expect((await reader.read()).value).toEqual(tail);
+  expect((await reader.read()).done).toBe(true);
+});
+
 function browserMocks() {
   const frames: any[] = []; const links: any[] = [];
   return { frames, links,
@@ -77,16 +137,18 @@ function browserMocks() {
 
 test("chat original downloads use a native CDN download without fetching the image through CORS", async () => {
   const dom = browserMocks(); const calls: string[] = [];
+  const progress: CanvasImageDownloadProgress[] = [];
   const client = serverLoader({ ...dom, fetch: async (url: string) => {
     calls.push(url);
     return Response.json({ delivery: "cdn", downloadUrl: "https://cdn.example/image.jpg?attname=original.jpg", filename: "original.jpg", bytes: 5000000 });
   } })("lib/client/canvas-image-download.ts");
-  const result = await client.downloadOriginalImage({ url: "https://cdn.example/image.jpg" });
+  const result = await client.downloadOriginalImage({ url: "https://cdn.example/image.jpg", onProgress: (event: CanvasImageDownloadProgress) => progress.push(event) });
   expect(result).toEqual({ filename: "original.jpg", bytes: 5000000 });
   expect(calls).toHaveLength(1);
   expect(new URL(calls[0], "https://app.example").searchParams.get("download")).toBe("resolve");
   expect(dom.frames[0].src).toBe("https://cdn.example/image.jpg?attname=original.jpg");
   expect(dom.links).toHaveLength(0);
+  expect(progress.map(event => event.phase)).toEqual(["preparing", "downloading"]);
 });
 
 test("original fallback preserves JPEG bytes and the MIME-derived filename", async () => {
@@ -99,6 +161,62 @@ test("original fallback preserves JPEG bytes and the MIME-derived filename", asy
   URL.revokeObjectURL(dom.links[0].href);
 });
 
+test("one click prepares a compatible PNG when the CDN original is WebP", async () => {
+  const dom = browserMocks();
+  const calls: string[] = [];
+  const progress: CanvasImageDownloadProgress[] = [];
+  const url = "https://cdn.example/image.png";
+  const client = serverLoader({ ...dom, fetch: async (path: string, init?: RequestInit) => {
+    calls.push(path);
+    if (calls.length === 1) {
+      return Response.json({ delivery: "cdn", downloadUrl: url, filename: "商品.webp", bytes: 500 });
+    }
+    expect(init?.method).toBe("POST");
+    expect(JSON.parse(String(init?.body))).toMatchObject({ url, name: "商品", preparation: "async" });
+    if (calls.length === 2) {
+      return Response.json({ delivery: "preparing", retryAfter: 1, message: "正在准备原图" }, { status: 202 });
+    }
+    return Response.json({ delivery: "cdn", downloadUrl: "https://cdn.example/prepared.png", filename: "商品.png", bytes: 900 });
+  } })("lib/client/canvas-image-download.ts");
+  expect(await client.downloadOriginalImage({ url, name: "商品", onProgress: (event: CanvasImageDownloadProgress) => progress.push(event) }))
+    .toEqual({ filename: "商品.png", bytes: 900 });
+  expect(calls.slice(1)).toEqual(["/api/canvas/download-image", "/api/canvas/download-image"]);
+  expect(progress.map(event => event.phase)).toEqual(["preparing", "converting", "converting", "downloading"]);
+  for (const event of progress.filter(event => event.phase === "converting")) {
+    expect(event.message).toContain("正在转换为兼容 PNG");
+    expect(event.percent).toBeUndefined();
+  }
+  expect(dom.frames.map(frame => frame.src)).toEqual(["https://cdn.example/prepared.png"]);
+  expect(dom.links).toHaveLength(0);
+});
+
+test("one click uses the PNG preparation route without buffering an incompatible proxy response", async () => {
+  const dom = browserMocks();
+  const calls: string[] = [];
+  const progress: CanvasImageDownloadProgress[] = [];
+  let cancelled = false;
+  const bytes = Uint8Array.of(137, 80, 78, 71, 13, 10, 26, 10);
+  const client = serverLoader({ ...dom, fetch: async (path: string) => {
+    calls.push(path);
+    if (calls.length === 1) return Response.json({ delivery: "proxy" });
+    if (calls.length === 2) {
+      return new Response(new ReadableStream({ cancel() { cancelled = true; } }),
+        { headers: { "content-type": "image/avif" } });
+    }
+    return new Response(bytes, { headers: { "content-type": "image/png", "content-length": String(bytes.length) } });
+  } })("lib/client/canvas-image-download.ts");
+  expect(await client.downloadOriginalImage({
+    url: "https://external.example/image", name: "商品", onProgress: (event: CanvasImageDownloadProgress) => progress.push(event),
+  })).toEqual({ filename: "商品.png", bytes: bytes.length });
+  expect(cancelled).toBe(true);
+  expect(calls[2]).toBe("/api/canvas/download-image");
+  expect(progress).toContainEqual({
+    phase: "downloading", message: "正在下载 PNG...", loadedBytes: bytes.length, totalBytes: bytes.length, percent: 99,
+  });
+  expect(dom.links).toHaveLength(1);
+  URL.revokeObjectURL(dom.links[0].href);
+});
+
 test("original downloads reject processed references before network access", async () => {
   const client = serverLoader({ ...browserMocks(), fetch() { throw new Error("Must not fetch a processed image as an original"); } })("lib/client/canvas-image-download.ts");
   await expect(client.downloadOriginalImage({ url: "https://cdn.example/image.jpg?imageView2/2/w/320&token=signed" })).rejects.toThrow("无法确认原图");