import { flushPromises, mount, type VueWrapper } from '@vue/test-utils';
import { defineComponent, ref } from 'vue';
import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
import { ApiError, postAlbumVisit } from '../api/client';
import { useVisitReport } from '../stats/visitor';
import { VISITOR_STORAGE_KEY } from '../stats/visitor';

// useVisitReport（Task 10 浏览上报编排）：加载成功且页面可见才报（隐藏时等
// 首次可见）/ 单相册一次 / 网络失败同 requestId 退避重试 / 4xx 静默放弃 /
// requestId 持久 sessionStorage 直到成功响应。visitorId 预置 localStorage
// 走快路径（跨标签协调单独在 visitor-id.spec 覆盖）。

vi.mock('../api/client', async (importOriginal) => {
  const actual = await importOriginal<typeof import('../api/client')>();
  return { ...actual, postAlbumVisit: vi.fn() };
});

const mockedPostAlbumVisit = vi.mocked(postAlbumVisit);

const mounted: VueWrapper[] = [];

function mountReport(token: string): ReturnType<typeof useVisitReport> {
  let report!: ReturnType<typeof useVisitReport>;
  const Host = defineComponent({
    setup() {
      report = useVisitReport({
        token: ref(token),
        onCounted: (count) => counted.push(count),
      });
      return () => null;
    },
  });
  mounted.push(mount(Host));
  return report;
}

const counted: number[] = [];

/** jsdom document.hidden 只读：defineProperty 覆写（用例后还原）。 */
function setHidden(hidden: boolean): void {
  Object.defineProperty(document, 'hidden', { configurable: true, get: () => hidden });
}

describe('visit report gating (Task 10)', () => {
  beforeEach(() => {
    localStorage.clear();
    sessionStorage.clear();
    localStorage.setItem(VISITOR_STORAGE_KEY, 'v'.repeat(32));
    counted.length = 0;
    mockedPostAlbumVisit.mockReset().mockResolvedValue({ viewCount: 1, counted: true });
    setHidden(false);
  });

  afterEach(() => {
    while (mounted.length > 0) mounted.pop()?.unmount();
    vi.useRealTimers();
    vi.restoreAllMocks();
    // 收尾后在途上报微任务可能仍落到已还原的替身（返回 undefined → .then 崩）：
    // 恢复后立即补挂兜底实现。
    mockedPostAlbumVisit.mockReset().mockResolvedValue({ viewCount: 0, counted: false });
    setHidden(false);
  });

  it('reports once after album load while visible, then clears the persisted requestId', async () => {
    const report = mountReport('tok-visit');
    report.notifyAlbumLoaded();
    await flushPromises();

    expect(mockedPostAlbumVisit).toHaveBeenCalledTimes(1);
    const [token, body] = mockedPostAlbumVisit.mock.calls[0]!;
    expect(token).toBe('tok-visit');
    expect(body.visitorId).toBe('v'.repeat(32));
    expect(body.requestId).toMatch(/^[0-9a-f-]{8,}$/);
    expect(counted).toEqual([1]);
    expect(sessionStorage.getItem('viewer.visitRequest:tok-visit')).toBeNull(); // 确认后清除

    report.notifyAlbumLoaded(); // 幂等：同相册只报一次
    await flushPromises();
    expect(mockedPostAlbumVisit).toHaveBeenCalledTimes(1);
  });

  it('defers the report until the page becomes visible', async () => {
    setHidden(true);
    const report = mountReport('tok-hidden');
    report.notifyAlbumLoaded();
    await flushPromises();
    expect(mockedPostAlbumVisit).not.toHaveBeenCalled();

    setHidden(false);
    document.dispatchEvent(new Event('visibilitychange'));
    await flushPromises();
    expect(mockedPostAlbumVisit).toHaveBeenCalledTimes(1);
  });

  it('retries network failure with the same persisted requestId and succeeds', async () => {
    mockedPostAlbumVisit
      .mockRejectedValueOnce(new ApiError('NETWORK_ERROR', 'network request failed', 0, null))
      .mockResolvedValue({ viewCount: 6, counted: true });
    vi.useFakeTimers();
    const report = mountReport('tok-retry');
    report.notifyAlbumLoaded();
    await vi.advanceTimersByTimeAsync(0);
    expect(mockedPostAlbumVisit).toHaveBeenCalledTimes(1);
    const requestId = mockedPostAlbumVisit.mock.calls[0]![1].requestId;
    // 失败期间 requestId 保持持久（刷新/重试幂等键不换）。
    expect(sessionStorage.getItem('viewer.visitRequest:tok-retry')).toBe(requestId);

    await vi.advanceTimersByTimeAsync(1000);
    expect(mockedPostAlbumVisit).toHaveBeenCalledTimes(2);
    expect(mockedPostAlbumVisit.mock.calls[1]![1].requestId).toBe(requestId);
    expect(counted).toEqual([6]);
    expect(sessionStorage.getItem('viewer.visitRequest:tok-retry')).toBeNull();
  });

  it('gives up silently on 4xx without retrying', async () => {
    mockedPostAlbumVisit.mockRejectedValue(new ApiError('RATE_LIMITED', 'too many', 429, null));
    vi.useFakeTimers();
    const report = mountReport('tok-4xx');
    report.notifyAlbumLoaded();
    await vi.advanceTimersByTimeAsync(0);
    expect(mockedPostAlbumVisit).toHaveBeenCalledTimes(1);

    await vi.advanceTimersByTimeAsync(10_000);
    expect(mockedPostAlbumVisit).toHaveBeenCalledTimes(1); // 无重试
  });
});