fix: preserve 4k image size across failover pipeline

app/(chat)/api/chat/route.ts

@@ -2828,6 +2828,12 @@ export async function POST(request: Request) {
                   const volcanoResult = await (volcanoLanguageModel as any).doGenerate({
                     messages: volcanoMessages,
                     maxImages: 1,  // 故障转移时只生成 1 张
+                    imageParams:
+                      effectiveImageParams || {
+                        aspectRatio: defaultImageQualityParams.aspectRatio,
+                        imageSize: defaultImageQualityParams.imageSize,
+                        imageCount: defaultImageQualityParams.imageCount,
+                      },
                   });
                   
                   const imageMarkdown = volcanoResult.text || "图片生成失败";

lib/ai/providers/volcano-vision.ts

@@ -17,6 +17,15 @@ type VolcanoUrlRewriteConfig = {
 let cachedRewriteConfig: VolcanoUrlRewriteConfig | null | undefined;
 const VOLCANO_IMAGE_FETCH_TIMEOUT_MS = 20_000;
 const VOLCANO_INLINE_MAX_SIDE = 1024;
+const DEFAULT_VOLCANO_IMAGE_SIZE = "2K";
+
+function normalizeVolcanoImageSize(imageSize?: string): "1K" | "2K" | "4K" {
+  const normalized = String(imageSize || "").trim().toUpperCase();
+  if (normalized === "1K" || normalized === "2K" || normalized === "4K") {
+    return normalized;
+  }
+  return DEFAULT_VOLCANO_IMAGE_SIZE;
+}
 
 function guessImageMimeTypeFromUrl(url: string): string {
   const cleanUrl = url.split("?")[0]?.toLowerCase() || "";
@@ -321,16 +330,19 @@ async function extractAndUploadImages(response: VolcanoVisionResponse): Promise<
  * 将图片数据转换为 Markdown 格式
  * 使用特殊格式传递缩略图和原图 URL：![thumb|原图URL](缩略图URL)
  */
-function formatImageResponse(images: Array<{ thumbnail: string; original: string }>): string {
+function formatImageResponse(
+  images: Array<{ thumbnail: string; original: string }>,
+  imageSize: string = DEFAULT_VOLCANO_IMAGE_SIZE
+): string {
   if (images.length === 0) {
     return "生成图片失败，未找到图片数据";
   }
 
   // 🆕 统一使用 ||| 分隔符格式（与 Gemini 保持一致）
   // 格式: ![thumb|||原图URL|||尺寸](缩略图URL)
-  // 豆包固定生成 2K 图片
+  const normalizedSize = normalizeVolcanoImageSize(imageSize);
   return images
-    .map((img) => `![thumb|||${img.original}|||2K](${img.thumbnail})`)
+    .map((img) => `![thumb|||${img.original}|||${normalizedSize}](${img.thumbnail})`)
     .join("\n\n");
 }
 
@@ -429,7 +441,8 @@ async function sendVolcanoRequest(
   apiKey: string,
   messages: any[],
   modelId: string,
-  maxImages: number = 3  // 默认 3 张，故障转移时传 1
+  maxImages: number = 3, // 默认 3 张，故障转移时传 1
+  imageSize: string = DEFAULT_VOLCANO_IMAGE_SIZE
 ): Promise<VolcanoVisionResponse> {
   const url = `${baseURL}/api/v3/images/generations`;
   
@@ -465,10 +478,11 @@ async function sendVolcanoRequest(
   console.log("[Volcano Vision] Image count:", image ? (Array.isArray(image) ? image.length : 1) : 0);
   
   // 构建请求体
+  const normalizedSize = normalizeVolcanoImageSize(imageSize);
   const requestBody: any = {
     model: modelId,
     prompt,
-    size: "2K",
+    size: normalizedSize,
     watermark: false,
     response_format: "url",
     stream: false,
@@ -579,7 +593,8 @@ async function* sendVolcanoStreamRequest(
   baseURL: string,
   apiKey: string,
   messages: any[],
-  modelId: string
+  modelId: string,
+  imageSize: string = DEFAULT_VOLCANO_IMAGE_SIZE
 ): AsyncGenerator<VolcanoVisionStreamEvent> {
   const url = `${baseURL}/api/v3/images/generations`;
   
@@ -593,10 +608,11 @@ async function* sendVolcanoStreamRequest(
   console.log("[Volcano Vision] Image count:", image ? (Array.isArray(image) ? image.length : 1) : 0);
   
   // 构建请求体
+  const normalizedSize = normalizeVolcanoImageSize(imageSize);
   const requestBody: any = {
     model: modelId,
     prompt,
-    size: "2K",
+    size: normalizedSize,
     watermark: false,
     response_format: "url",
     stream: true,
@@ -695,6 +711,7 @@ export function createVolcanoVision({ apiKey, baseURL }: VolcanoVisionConfig) {
         const activeModelId = options.overrideModelId || modelId;
         console.log("[Volcano Vision] Using modelId:", activeModelId);
         console.log("[Volcano Vision] Image params from options:", options.imageParams);
+        const imageSize = normalizeVolcanoImageSize(options.imageParams?.imageSize);
         
         // 🆕 优先使用用户选择的图片数量，其次是 maxImages 参数，默认 1 张
         const imageCount = options.imageParams?.imageCount || options.maxImages || 1;
@@ -703,11 +720,18 @@ export function createVolcanoVision({ apiKey, baseURL }: VolcanoVisionConfig) {
 
         try {
           // 发送请求
-          const response = await sendVolcanoRequest(baseURL, apiKey, options.messages, activeModelId, maxImages);
+          const response = await sendVolcanoRequest(
+            baseURL,
+            apiKey,
+            options.messages,
+            activeModelId,
+            maxImages,
+            imageSize
+          );
           
           // 提取图片并上传到 S3
           const imageUrls = await extractAndUploadImages(response);
-          const markdownText = formatImageResponse(imageUrls);
+          const markdownText = formatImageResponse(imageUrls, imageSize);
 
           console.log(
             `[Volcano Vision] Generated ${imageUrls.length} images (uploaded to S3)`
@@ -748,14 +772,15 @@ export function createVolcanoVision({ apiKey, baseURL }: VolcanoVisionConfig) {
           const allImages: Array<{ thumbnail: string; original: string }> = [];
           
           // 使用流式请求
-          for await (const event of sendVolcanoStreamRequest(baseURL, apiKey, options.messages, modelId)) {
+          const imageSize = normalizeVolcanoImageSize(options.imageParams?.imageSize);
+          for await (const event of sendVolcanoStreamRequest(baseURL, apiKey, options.messages, modelId, imageSize)) {
             if (event.type === "image_generation.partial_succeeded" && event.url) {
               // 每张图片生成完成后立即上传并发送
               try {
                 const imageUrls = await uploadImageToS3(event.url);
                 allImages.push(imageUrls);
                 
-                const markdown = `![thumb|${imageUrls.original}](${imageUrls.thumbnail})`;
+                const markdown = `![thumb|||${imageUrls.original}|||${imageSize}](${imageUrls.thumbnail})`;
                 console.log(`[Volcano Vision Stream] Image ${event.image_index} uploaded, sending...`);
                 
                 yield { type: "text-delta" as const, textDelta: markdown + "\n\n" };