修复连续对话误用缩略图导致画质下降

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

@@ -367,29 +367,13 @@ async function convertMessagesWithImages(messages: ChatMessage[], providerType:
   return convertedMessages;
 }
 
-/**
+function parseImageAltMetadata(altText: string, thumbnailUrl: string): {
- * 解析生图 Markdown 并保存图片记录到数据库
+  originalUrl: string;
- * 支持三种格式：thumb|||url|||size、thumb$$url$$size、thumb|url|size
+  imageSize: string;
- */
+} {
-async function saveGeneratedImages(
-  imageMarkdown: string,
-  userId: string,
-  chatId: string,
-  messageId: string,
-  prompt: string,
-  modelId: string
-): Promise<void> {
-  // 匹配 Markdown 图片格式: ![alt](url)
-  const imageRegex = /!\[([^\]]*)\]\(([^)]+)\)/g;
-  const matches = [...imageMarkdown.matchAll(imageRegex)];
-
-  for (const match of matches) {
-    const altText = match[1] || "";
-    const thumbnailUrl = match[2];
   let originalUrl = thumbnailUrl;
   let imageSize = "2K";
 
-    // 解析 alt 中的原图 URL 和尺寸
   // 格式1: thumb|||originalUrl|||size (新格式)
   if (altText.includes("thumb|||")) {
     const content = altText.substring(altText.indexOf("thumb|||") + 8);
@@ -421,14 +405,69 @@ async function saveGeneratedImages(
     } else if (thumbnailUrl.includes("volcano-thumb-")) {
       originalUrl = thumbnailUrl.replace("volcano-thumb-", "volcano-orig-");
     } else if (thumbnailUrl.includes("alibaba-image-thumb-")) {
-        // 🆕 阿里生图模型
       originalUrl = thumbnailUrl.replace("alibaba-image-thumb-", "alibaba-image-orig-");
     } else if (thumbnailUrl.includes("ruxa-image-thumb-")) {
-        // 🆕 RUXA 生图模型
       originalUrl = thumbnailUrl.replace("ruxa-image-thumb-", "ruxa-image-orig-");
     }
   }
 
+  return { originalUrl, imageSize };
+}
+
+function extractOriginalImageUrlsFromText(text: string): string[] {
+  const imageRegex = /!\[([^\]]*)\]\((https?:\/\/[^\s)]+)\)/g;
+  const imageUrls: string[] = [];
+  const added = new Set<string>();
+  let hasMarkdownImages = false;
+  let match: RegExpExecArray | null;
+
+  while ((match = imageRegex.exec(text)) !== null) {
+    hasMarkdownImages = true;
+    const altText = match[1] || "";
+    const thumbnailUrl = match[2];
+    const { originalUrl } = parseImageAltMetadata(altText, thumbnailUrl);
+    const finalUrl = originalUrl || thumbnailUrl;
+    if (finalUrl && /^https?:\/\//i.test(finalUrl) && !added.has(finalUrl)) {
+      added.add(finalUrl);
+      imageUrls.push(finalUrl);
+    }
+  }
+
+  if (!hasMarkdownImages) {
+    const urlRegex = /https?:\/\/[^\s"'<>]+\.(?:jpg|jpeg|png|gif|webp|bmp|svg)(?:\?[^\s"'<>]*)?/gi;
+    const matchedUrls = text.match(urlRegex) || [];
+    for (const url of matchedUrls) {
+      if (!added.has(url)) {
+        added.add(url);
+        imageUrls.push(url);
+      }
+    }
+  }
+
+  return imageUrls;
+}
+
+/**
+ * 解析生图 Markdown 并保存图片记录到数据库
+ * 支持三种格式：thumb|||url|||size、thumb$$url$$size、thumb|url|size
+ */
+async function saveGeneratedImages(
+  imageMarkdown: string,
+  userId: string,
+  chatId: string,
+  messageId: string,
+  prompt: string,
+  modelId: string
+): Promise<void> {
+  // 匹配 Markdown 图片格式: ![alt](url)
+  const imageRegex = /!\[([^\]]*)\]\(([^)]+)\)/g;
+  const matches = [...imageMarkdown.matchAll(imageRegex)];
+
+  for (const match of matches) {
+    const altText = match[1] || "";
+    const thumbnailUrl = match[2];
+    const { originalUrl, imageSize } = parseImageAltMetadata(altText, thumbnailUrl);
+
     try {
       await db.insert(generatedImage).values({
         userId,
@@ -595,11 +634,11 @@ export async function POST(request: Request) {
             if (msg.role === "assistant") {
               for (const part of parts) {
                 if (part.type === "text" && part.text) {
-                  // 匹配所有Markdown图片格式: ![alt](url)
+                  // 从 markdown 中优先提取原图 URL，避免把缩略图当作下一轮输入导致画质下降
-                  const imgMatches = part.text.matchAll(/!\[.*?\]\((https?:\/\/[^\s)]+)\)/g);
+                  const parsedImageUrls = extractOriginalImageUrlsFromText(part.text);
-                  for (const match of imgMatches) {
+                  for (const parsedUrl of parsedImageUrls) {
-                    if (match[1] && !smartAutoHistoryImages.includes(match[1])) {
+                    if (!smartAutoHistoryImages.includes(parsedUrl)) {
-                      smartAutoHistoryImages.push(match[1]);
+                      smartAutoHistoryImages.push(parsedUrl);
                     }
                   }
                 }