实现单篇和多篇论文的对比总结

src/modules/llm/history.ts

@@ -0,0 +1,76 @@
+import type { ChatMessage } from "../llm/types";
+
+/** Detect messages that already embed full paper dumps (should not be in UI history). */
+export function isPaperDump(content: string): boolean {
+  return (
+    content.includes("【论文正文】") ||
+    content.includes("【论文 1】") ||
+    content.startsWith("【论文元数据】") ||
+    content.startsWith("已收到论文内容") ||
+    content.includes("【说明】以上为本次会话的论文材料")
+  );
+}
+
+/**
+ * Keep short Q&A turns for the model. Truncate very long assistant replies
+ * so paper context + latest question are less likely to be dropped.
+ */
+export function sanitizeChatHistory(
+  history: ChatMessage[],
+  options?: { maxMessages?: number; maxAssistantChars?: number },
+): ChatMessage[] {
+  const maxMessages = options?.maxMessages ?? 10;
+  const maxAssistantChars = options?.maxAssistantChars ?? 5000;
+
+  const cleaned = history
+    .filter((m) => m.role === "user" || m.role === "assistant")
+    .filter((m) => !isPaperDump(m.content))
+    .map((m) => {
+      if (
+        m.role === "assistant" &&
+        m.content &&
+        m.content.length > maxAssistantChars
+      ) {
+        return {
+          ...m,
+          content:
+            m.content.slice(0, maxAssistantChars) +
+            "\n\n…（为保留论文上下文，历史回复已截断）",
+        };
+      }
+      return m;
+    });
+
+  return cleaned.slice(-maxMessages);
+}
+
+/**
+ * Pin paper corpus near the start of the request, then prior Q&A, then the
+ * current task. Avoids stuffing full papers only into the latest message
+ * (which providers often truncate under context pressure on turn 2+).
+ */
+export function assemblePaperChatMessages(options: {
+  system: string;
+  paperBlock: string;
+  taskBlock: string;
+  history: ChatMessage[];
+}): ChatMessage[] {
+  const messages: ChatMessage[] = [
+    { role: "system", content: options.system },
+    {
+      role: "user",
+      content: `${options.paperBlock}
+
+【说明】以上为本次会话的论文材料。后续所有问题与分析任务均基于这些论文；无需用户再次提供全文或文本。`,
+    },
+    {
+      role: "assistant",
+      content:
+        "已收到并理解以上论文材料。请继续提问或下达分析任务，我将基于这些论文作答，不会要求你再次提供全文。",
+    },
+  ];
+
+  messages.push(...sanitizeChatHistory(options.history));
+  messages.push({ role: "user", content: options.taskBlock });
+  return messages;
+}