server.ts

import express, { Request, Response, NextFunction } from "express";
import Anthropic from "@anthropic-ai/sdk";
import * as dl from "dongnelibrary";
import type { SearchResult, Book } from "dongnelibrary";
import * as ansan from "dongnelibrary/dist/localLibraryModule/ansan";
import * as asan from "dongnelibrary/dist/localLibraryModule/asan";
import * as bcl from "dongnelibrary/dist/localLibraryModule/bcl";
import * as cbelib from "dongnelibrary/dist/localLibraryModule/cbelib";
import * as daegu from "dongnelibrary/dist/localLibraryModule/daegu";
import * as gangnam from "dongnelibrary/dist/localLibraryModule/gangnam";
import * as gangseo from "dongnelibrary/dist/localLibraryModule/gangseo";
import * as gbelib from "dongnelibrary/dist/localLibraryModule/gbelib";
import * as geoje from "dongnelibrary/dist/localLibraryModule/geoje";
import * as gg from "dongnelibrary/dist/localLibraryModule/gg";
import * as gimhae from "dongnelibrary/dist/localLibraryModule/gimhae";
import * as gjcity from "dongnelibrary/dist/localLibraryModule/gjcity";
import * as gunpo from "dongnelibrary/dist/localLibraryModule/gunpo";
import * as gunsan from "dongnelibrary/dist/localLibraryModule/gunsan";
import * as gwanak from "dongnelibrary/dist/localLibraryModule/gwanak";
import * as gwe from "dongnelibrary/dist/localLibraryModule/gwe";
import * as hanamlib from "dongnelibrary/dist/localLibraryModule/hanamlib";
import * as hscity from "dongnelibrary/dist/localLibraryModule/hscity";
import * as ice from "dongnelibrary/dist/localLibraryModule/ice";
import * as jeju from "dongnelibrary/dist/localLibraryModule/jeju";
import * as junggulib from "dongnelibrary/dist/localLibraryModule/junggulib";
import * as mokpolib from "dongnelibrary/dist/localLibraryModule/mokpolib";
import * as nowon from "dongnelibrary/dist/localLibraryModule/nowon";
import * as osan from "dongnelibrary/dist/localLibraryModule/osan";
import * as paju from "dongnelibrary/dist/localLibraryModule/paju";
import * as pohang from "dongnelibrary/dist/localLibraryModule/pohang";
import * as ptlib from "dongnelibrary/dist/localLibraryModule/ptlib";
import * as siheung from "dongnelibrary/dist/localLibraryModule/siheung";
import * as snlib from "dongnelibrary/dist/localLibraryModule/snlib";
import * as suwon from "dongnelibrary/dist/localLibraryModule/suwon";
import * as uwlib from "dongnelibrary/dist/localLibraryModule/uwlib";
import * as wonju from "dongnelibrary/dist/localLibraryModule/wonju";
import * as yangcheon from "dongnelibrary/dist/localLibraryModule/yangcheon";
import * as ydplib from "dongnelibrary/dist/localLibraryModule/ydplib";
import * as yjlib from "dongnelibrary/dist/localLibraryModule/yjlib";
import * as yongin from "dongnelibrary/dist/localLibraryModule/yongin";
import * as yplib from "dongnelibrary/dist/localLibraryModule/yplib";
import * as yslib from "dongnelibrary/dist/localLibraryModule/yslib";

const LIBRARY_MODULES = [ansan, asan, bcl, cbelib, daegu, gangnam, gangseo, gbelib, geoje, gg, gimhae, gjcity, gunpo, gunsan, gwanak, gwe, hanamlib, hscity, ice, jeju, junggulib, mokpolib, nowon, osan, paju, pohang, ptlib, siheung, snlib, suwon, uwlib, wonju, yangcheon, ydplib, yjlib, yongin, yplib, yslib];

const app = express();

app.use(express.json());
app.use("/", express.static(import.meta.dirname + "/dist"));

interface SearchParams {
  title: string;
  libraryName: string;
}

const searchBooks = (
  title: string,
  libraryName: string,
  signal?: AbortSignal,
): Promise<SearchResult[]> => {
  return new Promise((resolve, reject) => {
    dl.search({ title, libraryName, signal }, undefined, (err, books) => {
      if (err) {
        console.error(err);
        reject(err);
      } else {
        resolve(books ?? []);
      }
    });
  });
};

const extractSearchParams = (
  params: Record<string, unknown>,
): SearchParams => ({
  title: (params.title as string) || "",
  libraryName: (params.libraryName as string) || "",
});

const makeBookDescription = (book: Book): string => {
  const mark = book.exist ? "✓ " : "✖ ";
  return " " + mark + " " + book.title + "<br>";
};

app.get("/search", async (req: Request, res: Response) => {
  const controller = new AbortController();

  req.on("close", () => {
    controller.abort();
  });

  const { title, libraryName } = extractSearchParams(req.query);

  try {
    const books = await searchBooks(title, libraryName, controller.signal);

    if (res.writableEnded) return;
    res.json(books);
  } catch (err) {
    if (res.writableEnded) return;

    const error = err as { msg?: string };
    res.json({ message: error.msg });
  }
});

app.get("/libraryList", (_req: Request, res: Response) => {
  const libs = dl.getAllLibraryNames();
  res.json(libs);
});

app.get("/moduleList", (_req: Request, res: Response) => {
  const modules = LIBRARY_MODULES.map((mod) => ({
    name: mod.moduleName,
    libraries: mod.getLibraryNames(),
  }));
  res.json(modules);
});

app.get("/:title/:libraryName", async (req: Request, res: Response) => {
  const { title, libraryName } = extractSearchParams(req.params);

  try {
    const books = await searchBooks(title, libraryName);
    res.send(
      books[0].booklist.reduce((memo: string, book: Book) => {
        return memo + makeBookDescription(book);
      }, ""),
    );
  } catch (err) {
    const error = err as { msg?: string };
    res.json({ message: error.msg });
  }
});

// ── Agent Stream proxy ──────────────────────────────────────────────────────

type AgentEventType = "core_agent" | "domain_agent" | "tool_call" | "tool_result" | "response";
interface AgentEvent { type: AgentEventType; data: unknown }

const AGENT_TOOLS: Anthropic.Messages.Tool[] = [
  {
    name: "list_libraries",
    description: "검색 가능한 전체 도서관 목록을 반환합니다.",
    input_schema: { type: "object" as const, properties: {}, required: [] },
  },
  {
    name: "search_books",
    description: "도서 제목과 도서관 이름으로 대출 가능 여부를 검색합니다.",
    input_schema: {
      type: "object" as const,
      properties: {
        title: { type: "string", description: "검색할 도서 제목" },
        libraryName: { type: "string", description: "검색할 도서관 이름 (예: 판교)" },
      },
      required: ["title", "libraryName"],
    },
  },
];

async function callAgentTool(
  name: string,
  input: Record<string, unknown>,
  signal: AbortSignal,
): Promise<string> {
  if (name === "list_libraries") {
    return JSON.stringify(dl.getAllLibraryNames());
  }
  if (name === "search_books") {
    const { title, libraryName } = input as { title: string; libraryName: string };
    try {
      const books = await searchBooks(title, libraryName, signal);
      return JSON.stringify(books).slice(0, 1200);
    } catch (e) {
      return `Error: ${e instanceof Error ? e.message : "search failed"}`;
    }
  }
  return "Unknown tool";
}

app.options("/api/agent-stream", (_req: Request, res: Response) => {
  res.setHeader("Access-Control-Allow-Origin", "*");
  res.setHeader("Access-Control-Allow-Methods", "POST, OPTIONS");
  res.setHeader("Access-Control-Allow-Headers", "Content-Type");
  res.sendStatus(204);
});

app.post("/api/agent-stream", async (req: Request, res: Response) => {
  const { query } = req.body as { query: string };

  res.setHeader("Access-Control-Allow-Origin", "*");
  res.setHeader("Content-Type", "text/event-stream");
  res.setHeader("Cache-Control", "no-cache");
  res.setHeader("Connection", "keep-alive");

  const controller = new AbortController();
  res.on("close", () => controller.abort());

  const send = (event: AgentEvent) => {
    res.write(`data: ${JSON.stringify(event)}\n\n`);
  };

  const heartbeat = setInterval(() => {
    if (!res.writableEnded) res.write(': ping\n\n');
  }, 1000);

  try {
    const anthropic = new Anthropic({ apiKey: process.env.ANTHROPIC_API_KEY });

    send({ type: "core_agent", data: { intent: "Knowledge", confidence: 0.95, reason: "도서관 도서 검색 쿼리 감지" } });
    send({ type: "domain_agent", data: { name: "도서관 검색 Agent (dlserver)" } });

    const messages: Anthropic.Messages.MessageParam[] = [
      { role: "user", content: query },
    ];

    let firstIteration = true;
    while (true) {
      if (controller.signal.aborted) break;

      const response = await anthropic.messages.create({
        model: "claude-haiku-4-5-20251001",
        max_tokens: 1024,
        system: `당신은 도서관 도서 검색 에이전트입니다.
사용자가 책 제목과 도서관 이름을 말하면 즉시 search_books 도구를 호출하세요.
- title: 사용자가 말한 책 제목 그대로 (절대 바꾸지 마세요)
- libraryName: 사용자가 말한 도서관 이름 그대로 (예: "판교", "강남")
list_libraries는 사용자가 도서관 이름을 모를 때만 사용하세요.`,
        tools: AGENT_TOOLS,
        tool_choice: firstIteration ? { type: "any" as const } : { type: "auto" as const },
        messages,
      });
      firstIteration = false;

      if (response.stop_reason === "tool_use") {
        const toolUseBlocks = response.content.filter(
          (b): b is Anthropic.Messages.ToolUseBlock => b.type === "tool_use",
        );
        const toolResults: Anthropic.Messages.ToolResultBlockParam[] = [];

        for (const block of toolUseBlocks) {
          if (controller.signal.aborted) break;

          send({
            type: "tool_call",
            data: {
              name: block.name,
              description: AGENT_TOOLS.find((t) => t.name === block.name)?.description ?? "",
              input: block.input as Record<string, unknown>,
            },
          });

          const output = await callAgentTool(
            block.name,
            block.input as Record<string, unknown>,
            controller.signal,
          );

          if (controller.signal.aborted) break;

          send({ type: "tool_result", data: { toolName: block.name, output } });
          toolResults.push({ type: "tool_result", tool_use_id: block.id, content: output });
        }

        messages.push({ role: "assistant", content: response.content });
        messages.push({ role: "user", content: toolResults });
      } else {
        const textBlock = response.content.find(
          (b): b is Anthropic.Messages.TextBlock => b.type === "text",
        );
        send({ type: "response", data: textBlock?.text ?? "검색 결과를 찾을 수 없습니다." });
        break;
      }
    }
  } catch (e) {
    console.error("[agent-stream] error:", e);
    send({ type: "response", data: `오류: ${e instanceof Error ? e.message : "알 수 없는 오류"}` });
  } finally {
    clearInterval(heartbeat);
  }

  res.end();
});

// ────────────────────────────────────────────────────────────────────────────

interface HttpError extends Error {
  status?: number;
}

app.use((_req: Request, _res: Response, next: NextFunction) => {
  const err: HttpError = new Error("Not Found");
  err.status = 404;
  next(err);
});

app.use((err: HttpError, _req: Request, res: Response, _next: NextFunction) => {
  res.status(err.status || 500);
  res.json({ message: "Server Error" });
});

export { app };

const isMainModule = import.meta.url === `file://${process.argv[1]}`;
if (isMainModule) {
  const port = process.env.PORT || 3000;
  app.listen(port, () => {
    console.log(`dlserver listening on port ${port}!`);
  });
}