import { afterEach, expect, it } from "bun:test";
import express from "express";
import { mkdtemp, rm } from "node:fs/promises";
import type { Server } from "node:http";
import { tmpdir } from "node:os";
import { join } from "node:path";
import { buildChatRouter } from "../../src/routes/chat.js";
import { SessionMetadataStore } from "../../src/sessions/metadataStore.js";
import { SessionUiStateStore } from "../../src/sessions/uiStateStore.js";
import { SessionWorkspaceStore } from "../../src/sessions/workspace-store.js";
import { toActorKey, toProjectKey } from "../../src/utils/fileStore.js";

const http = globalThis.fetch;
const projectId = "10000000-0000-4000-8000-000000000001";
const firstTask = "50000000-0000-4000-8000-000000000001";
const secondTask = "50000000-0000-4000-8000-000000000002";
let root: string | undefined;
let server: Server | undefined;

afterEach(async () => {
  globalThis.fetch = http;
  if (server) {
    server.closeAllConnections();
    await new Promise<void>((resolve) => server!.close(() => resolve()));
    server = undefined;
  }
  if (root) { await rm(root, { recursive: true, force: true }); root = undefined; }
});

async function fixture() {
  root = await mkdtemp(join(tmpdir(), "tjwater-collaboration-titles-"));
  const context = { actorKey: toActorKey("product:owner"), projectKey: toProjectKey(`product:${projectId}`), projectId, userId: "owner" };
  const workspaces = new SessionWorkspaceStore(join(root, "workspaces"));
  const sessions = new SessionMetadataStore(join(root, "metadata"), workspaces);
  const states = new SessionUiStateStore(join(root, "states"), workspaces);
  const taskNames = new Map([[firstTask, "南桥管道爆管调查"], [secondTask, "城南供水压力复核"]]);
  const taskReads: string[] = [];
  let available = true;
  let onTaskRead: (() => Promise<unknown>) | undefined;
  let waitForAbort = false;
  let observedAbort = false;
  globalThis.fetch = (async (input, init) => {
    const path = new URL(String(input)).pathname;
    const taskId = path.match(/\/operational-tasks\/([^/]+)\/agent-context$/)?.[1];
    if (taskId) {
      taskReads.push(taskId);
      await onTaskRead?.();
      if (waitForAbort) return await new Promise<Response>((_resolve, reject) => {
        const signal = init?.signal;
        if (!signal) { reject(new Error("expected title lookup cancellation signal")); return; }
        const abort = () => { observedAbort = true; reject(new DOMException("aborted", "AbortError")); };
        if (signal.aborted) abort(); else signal.addEventListener("abort", abort, { once: true });
      });
      if (!available) return Response.json({ message: "task context unavailable" }, { status: 503 });
      return Response.json({ task: {
        task_id: taskId, task_type: "event_investigation", workflow: "burst-report",
        lifecycle_status: "waiting_human", active_run: null, status: "waiting_human", revision: 1,
        execution_request_id: "60000000-0000-4000-8000-000000000001",
        title: taskNames.get(taskId) ?? "其他现场调查", summary: "核对现场事实与模型结果",
        latest_plan: null, latest_report: null, evidence: [], actions: [], permissions: {},
      }, approved_data_scopes: [] });
    }
    const headers = new Headers(init?.headers);
    return Response.json({ user_id: headers.get("authorization") === "Bearer owner" ? "owner" : "other",
      project_id: headers.get("x-project-id"), network: "supply" });
  }) as typeof fetch;
  let created = 0;
  const app = express();
  app.use(express.json());
  app.use("/api/v1", buildChatRouter({ sessionMetadataStore: sessions, sessionUiStateStore: states,
    runtime: { createSession: async () => ({ id: `collaboration-${++created}` }) } as never,
    sessionBridge: {} as never, sessionTranscriptStore: {} as never, memoryStore: {} as never,
    learningOrchestrator: {} as never, frontendActionCoordinator: {} as never }));
  server = app.listen(0, "127.0.0.1");
  await new Promise<void>((resolve) => server!.once("listening", resolve));
  const address = server.address();
  if (!address || typeof address === "string") throw new Error("missing server address");
  const request = async (path: string, method = "GET", user = "owner") => {
    const response = await http(`http://127.0.0.1:${address.port}/api/v1${path}`, {
      method, headers: { Authorization: `Bearer ${user}`, "X-Project-Id": projectId },
    });
    return { status: response.status, body: await response.json() as Record<string, any> };
  };
  const seed = async (sessionId: string, taskId: string, title: string, manuallyEdited = false) => {
    const { record } = await sessions.ensure({ ...context, sessionId, taskId, purpose: "task_collaboration" });
    const titled = await sessions.touch(record, { title });
    await states.write({ ...context, sessionId }, { sessionId, messages: [], isTitleManuallyEdited: manuallyEdited });
    return titled;
  };
  return { request, seed, sessions, context, taskReads, setAvailable: (value: boolean) => { available = value; },
    setTaskReadHook: (hook: () => Promise<unknown>) => { onTaskRead = hook; },
    waitForTitleAbort: () => { waitForAbort = true; }, didAbort: () => observedAbort };
}

it("names new collaboration sessions after their verified tasks", async () => {
  const { request, taskReads } = await fixture();
  const first = await request(`/task/${firstTask}/collaboration/session`, "POST");
  const second = await request(`/task/${secondTask}/collaboration/session`, "POST");
  expect(first.status).toBe(201);
  expect(second.status).toBe(201);
  expect(first.body.title).toBe("南桥管道爆管调查");
  expect(second.body.title).toBe("城南供水压力复核");
  const history = await request("/sessions?include_collaboration=true");
  expect(history.body.sessions.map((item: { title: string }) => item.title).sort()).toEqual(["南桥管道爆管调查", "城南供水压力复核"]);
  expect((await request(`/session/${first.body.session_id}`)).body.title).toBe("南桥管道爆管调查");
  expect(taskReads).toHaveLength(2);
});

it("repairs returned legacy history without changing timestamps or custom names, then searches the repaired titles", async () => {
  const { request, seed, sessions, context, taskReads } = await fixture();
  const first = await seed("legacy-first", firstTask, "任务协作");
  const second = await seed("legacy-second", secondTask, "任务协作问答");
  await seed("custom", firstTask, "现场沟通记录");
  await seed("manual-generic", secondTask, "任务协作", true);
  await request("/sessions?include_collaboration=true");
  const result = await request(`/sessions?include_collaboration=true&q=${encodeURIComponent("城南供水压力复核")}`);
  expect(result.body.sessions.map((item: { id: string }) => item.id)).toEqual(["legacy-second"]);
  expect(await sessions.get(context, first.sessionId)).toMatchObject({ title: "南桥管道爆管调查", updatedAt: first.updatedAt });
  expect(await sessions.get(context, second.sessionId)).toMatchObject({ title: "城南供水压力复核", updatedAt: second.updatedAt });
  expect((await sessions.get(context, "custom"))?.title).toBe("现场沟通记录");
  expect((await sessions.get(context, "manual-generic"))?.title).toBe("任务协作");
  expect(taskReads.sort()).toEqual([firstTask, secondTask]);
  expect((await request("/sessions?include_collaboration=true", "GET", "other")).body.sessions).toEqual([]);
  expect((await request("/session/legacy-first", "GET", "other")).status).toBe(404);
});

it("repairs only the returned history page and continues on the next page", async () => {
  const { request, seed, taskReads } = await fixture();
  for (let index = 0; index < 12; index += 1) await seed(`legacy-${index}`, firstTask, "任务协作");
  const first = await request("/sessions?include_collaboration=true&limit=1");
  expect(first.body.sessions).toHaveLength(1);
  expect(first.body.sessions[0].title).toBe("南桥管道爆管调查");
  expect(taskReads).toHaveLength(1);
  const next = await request(`/sessions?include_collaboration=true&limit=1&cursor=${encodeURIComponent(first.body.next_cursor)}`);
  expect(next.body.sessions[0].id).not.toBe(first.body.sessions[0].id);
  expect(next.body.sessions[0].title).toBe("南桥管道爆管调查");
  expect(taskReads).toHaveLength(2);
});

it("cancels slow title lookups within the history request budget", async () => {
  const { request, seed, waitForTitleAbort, didAbort, taskReads } = await fixture();
  await seed("slow-title", firstTask, "任务协作");
  waitForTitleAbort();
  const started = Date.now();
  const result = await request("/sessions?include_collaboration=true&limit=1");
  expect(result.status).toBe(200);
  expect(result.body.sessions[0].title).toBe("任务协作");
  expect(didAbort()).toBe(true);
  expect(taskReads).toHaveLength(1);
  expect(Date.now() - started).toBeLessThan(3_500);
});

it("returns the current title when it changes while task access is being validated", async () => {
  const { request, seed, sessions, setTaskReadHook } = await fixture();
  const record = await seed("changing-title", firstTask, "南桥管道爆管调查");
  setTaskReadHook(() => sessions.touch(record, { title: "Agent生成的新标题" }));
  const result = await request(`/task/${firstTask}/collaboration/session`, "POST");
  expect(result.body.title).toBe("Agent生成的新标题");
});

it("repairs legacy sessions when loaded or reused and returns the updated title", async () => {
  const { request, seed } = await fixture();
  const first = await seed("legacy-load", firstTask, "任务协作");
  await seed("legacy-reuse", secondTask, "任务协作问答");
  const loaded = await request("/session/legacy-load");
  expect(loaded.body.title).toBe("南桥管道爆管调查");
  expect(loaded.body.updated_at).toBe(first.updatedAt);
  const reused = await request(`/task/${secondTask}/collaboration/session`, "POST");
  expect(reused.status).toBe(200);
  expect(reused.body).toMatchObject({ session_id: "legacy-reuse", title: "城南供水压力复核", created: false });
});

it("keeps history readable during task API failures and retries title repair later", async () => {
  const { request, seed, setAvailable } = await fixture();
  await seed("legacy-unavailable", firstTask, "任务协作");
  setAvailable(false);
  const result = await request("/sessions?include_collaboration=true");
  expect(result.status).toBe(200);
  expect(result.body.sessions[0].title).toBe("任务协作");
  setAvailable(true);
  expect((await request("/sessions?include_collaboration=true")).body.sessions[0].title).toBe("南桥管道爆管调查");
});

it("does not overwrite a title changed after a legacy record was read", async () => {
  const { seed, sessions, context } = await fixture();
  const stale = await seed("renamed", firstTask, "任务协作");
  await sessions.touch(stale, { title: "我自己的任务备注" });
  await sessions.touch(stale, { title: "南桥管道爆管调查" }, { preserveUpdatedAt: true, expectedTitle: stale.title });
  expect((await sessions.get(context, stale.sessionId))?.title).toBe("我自己的任务备注");
});