拆分 chat.ts 文件，明确功能边界

src/routes/chatSession.ts

@@ -0,0 +1,144 @@
+import { logger } from "../logger.js";
+import { MemoryStore } from "../memory/store.js";
+import { type OpencodeRuntimeAdapter } from "../runtime/opencode.js";
+
+import { collectTextContent } from "./chatStream.js";
+
+const TITLE_PROMPT_TIMEOUT_MS = 2500;
+
+const buildSessionTitle = (message: string) => {
+  const normalized = message.replace(/\s+/g, " ").trim();
+  if (!normalized) {
+    return "新对话";
+  }
+  return normalized.length > 24 ? `${normalized.slice(0, 24)}...` : normalized;
+};
+
+const buildTitleConversationContext = async (
+  runtime: OpencodeRuntimeAdapter,
+  sessionId: string,
+) => {
+  const messages = await runtime.messages(sessionId, 12);
+  const recentMessages = messages
+    .filter(
+      (message) =>
+        message.info.role === "user" || message.info.role === "assistant",
+    )
+    .map((message) => ({
+      role: message.info.role,
+      content: collectTextContent(message.parts).replace(/\s+/g, " ").trim(),
+    }))
+    .filter((message) => message.content.length > 0)
+    .slice(-6);
+
+  if (recentMessages.length === 0) {
+    return "";
+  }
+
+  return recentMessages
+    .map((message) => `${message.role === "user" ? "用户" : "助手"}：${message.content}`)
+    .join("\n")
+    .slice(0, 2400);
+};
+
+const normalizeGeneratedTitle = (rawTitle: string, fallback: string) => {
+  const normalized = rawTitle
+    .replace(/\s+/g, " ")
+    .replace(/["'“”‘’`]/g, "")
+    .trim();
+  if (!normalized) {
+    return fallback;
+  }
+  return normalized.length > 24 ? `${normalized.slice(0, 24)}...` : normalized;
+};
+
+export const generateSessionTitle = async (
+  runtime: OpencodeRuntimeAdapter,
+  options: {
+    sessionId: string;
+    latestUserMessage: string;
+    fallbackTitle?: string;
+  },
+) => {
+  const fallback = options.fallbackTitle?.trim() || buildSessionTitle(options.latestUserMessage);
+  let titleSessionId: string | undefined;
+  try {
+    const conversation = await buildTitleConversationContext(runtime, options.sessionId);
+    if (!conversation) {
+      return fallback;
+    }
+
+    const titleSession = await runtime.createSession(`title-${Date.now().toString(36)}`);
+    titleSessionId = titleSession.id;
+    const request = runtime
+      .prompt(
+        titleSession.id,
+        [
+          "你是会话标题生成器。",
+          "请根据用户问题生成一个 8-16 字中文标题。",
+          "要求：简洁、可读、避免标点、不要引号、不要解释。",
+          "请优先概括最近这轮对话的核心任务或结论。",
+          "只输出标题本身。",
+          "",
+          conversation,
+        ].join("\n"),
+      )
+      .then(async () => {
+        const messages = await runtime.messages(titleSession.id, 20);
+        const assistantMessage = [...messages]
+          .reverse()
+          .find((message) => message.info.role === "assistant");
+        const title = collectTextContent(assistantMessage?.parts ?? []);
+        return normalizeGeneratedTitle(title, fallback);
+      });
+
+    const timeout = new Promise<string>((resolve) => {
+      setTimeout(() => resolve(fallback), TITLE_PROMPT_TIMEOUT_MS);
+    });
+
+    return await Promise.race([request, timeout]);
+  } catch (error) {
+    logger.warn({ err: error }, "failed to generate session title, using fallback");
+    return fallback;
+  } finally {
+    if (titleSessionId) {
+      await runtime.abortSession(titleSessionId).catch((error) => {
+        logger.debug({ sessionId: titleSessionId, err: error }, "failed to cleanup title session");
+      });
+    }
+  }
+};
+
+export const getConversationTurnStats = async (
+  runtime: OpencodeRuntimeAdapter,
+  sessionId: string,
+) => {
+  const messages = await runtime.messages(sessionId, 12);
+  return messages.reduce(
+    (stats, message) => {
+      if (message.info.role === "user") {
+        stats.userMessageCount += 1;
+      } else if (message.info.role === "assistant") {
+        stats.assistantMessageCount += 1;
+      }
+      return stats;
+    },
+    {
+      userMessageCount: 0,
+      assistantMessageCount: 0,
+    },
+  );
+};
+
+export const buildPromptWithLearningContext = async (
+  memoryStore: MemoryStore,
+  actorKey: string,
+  projectKey: string,
+  message: string,
+) => {
+  const snapshot = await memoryStore.buildPromptSnapshot({ actorKey, projectKey });
+  if (!snapshot) {
+    return message;
+  }
+  return `${snapshot}\n\n[Current user request]\n${message}`;
+};