MailUI4Agents/client/electron/test/stores/background.test.ts

import { beforeEach, describe, expect, it } from 'vitest';
import {
  DEFAULT_BACKGROUND,
  MAX_DATA_URL_BYTES,
  STORAGE_KEY,
  applyBackground,
  clampBlur,
  clampDim,
  normalizeBackground,
  useBackgroundStore
} from '../../src/stores/backgroundStore';

/**
 * 背景 store 的行为锁。
 *
 * 这里测的是**纯逻辑与 DOM 写入**（不需要真浏览器）：
 *   - 脏数据不能让界面白屏（localStorage 可能被手改、也可能来自旧版本）
 *   - 数值必须被夹在合法区间（滑杆之外的写入路径只有代码，但状态可能来自磁盘）
 *   - CSS 变量的写入/清理必须成对 —— 残留的 `--bg-image` 会让「关掉背景」
 *     之后仍然显示上一张图
 */

const presetClasses = () =>
  Array.from(document.documentElement.classList).filter(c => c.startsWith('bg-preset-'));

beforeEach(() => {
  localStorage.clear();
  document.documentElement.removeAttribute('data-bg');
  document.documentElement.removeAttribute('style');
  document.documentElement.className = '';
});

describe('数值夹取', () => {
  it('压暗与模糊都被夹在声明区间内', () => {
    expect(clampDim(-10)).toBe(0);
    expect(clampDim(999)).toBe(80);
    expect(clampDim(30)).toBe(30);
    expect(clampBlur(-1)).toBe(0);
    expect(clampBlur(100)).toBe(24);
    expect(clampBlur(10)).toBe(10);
  });

  it('非数值退回默认值而不是 NaN', () => {
    // NaN 会写成 `--bg-dim: NaN%`，整条声明失效 —— 表现为滑杆无效但不报错
    expect(clampDim(Number.NaN)).toBe(DEFAULT_BACKGROUND.dim);
    expect(clampBlur(Number.NaN)).toBe(DEFAULT_BACKGROUND.blur);
  });
});

describe('脏数据归一化', () => {
  it('非对象输入退回默认', () => {
    for (const bad of [null, undefined, 42, 'x', []]) {
      const n = normalizeBackground(bad);
      expect(n.kind).toBe('none');
      expect(n.presetId).toBe(DEFAULT_BACKGROUND.presetId);
    }
  });

  it('未知预设 id 退回默认预设', () => {
    expect(normalizeBackground({ presetId: 'no-such-preset' }).presetId).toBe(
      DEFAULT_BACKGROUND.presetId
    );
  });

  it('kind=image 但没有可用图片时退回 none', () => {
    // 图片可能被浏览器清理或写坏。留一个空壳 image 状态会让界面显示「已选图片」
    // 却什么都没有 —— 不如退回 none，至少状态是诚实的
    expect(normalizeBackground({ kind: 'image', imageDataUrl: '' }).kind).toBe('none');
    expect(normalizeBackground({ kind: 'image', imageDataUrl: 'https://x/y.png' }).kind).toBe('none');
  });

  it('合法 data URL 被保留', () => {
    const url = 'data:image/jpeg;base64,AAAA';
    const n = normalizeBackground({ kind: 'image', imageDataUrl: url });
    expect(n.kind).toBe('image');
    expect(n.imageDataUrl).toBe(url);
  });

  it('越界数值被夹回区间', () => {
    const n = normalizeBackground({ dim: 500, blur: -5 });
    expect(n.dim).toBe(80);
    expect(n.blur).toBe(0);
  });
});

describe('写 DOM', () => {
  it('预设背景写入 data-bg、预设类与两个数值变量', () => {
    applyBackground({ ...DEFAULT_BACKGROUND, kind: 'preset', presetId: 'dusk', dim: 40, blur: 12 });
    const root = document.documentElement;
    expect(root.dataset.bg).toBe('on');
    expect(presetClasses()).toEqual(['bg-preset-dusk']);
    expect(root.style.getPropertyValue('--bg-dim')).toBe('40%');
    expect(root.style.getPropertyValue('--bg-blur')).toBe('12px');
    // 预设的渐变由 class 提供，不得写 --bg-image（否则会盖住 class 的定义）
    expect(root.style.getPropertyValue('--bg-image')).toBe('');
  });

  it('切换预设时清掉上一个预设类', () => {
    applyBackground({ ...DEFAULT_BACKGROUND, kind: 'preset', presetId: 'aurora' });
    applyBackground({ ...DEFAULT_BACKGROUND, kind: 'preset', presetId: 'mint' });
    expect(presetClasses()).toEqual(['bg-preset-mint']);
  });

  it('图片背景写入 --bg-image 并清掉预设类', () => {
    applyBackground({ ...DEFAULT_BACKGROUND, kind: 'preset', presetId: 'aurora' });
    applyBackground({
      ...DEFAULT_BACKGROUND,
      kind: 'image',
      imageDataUrl: 'data:image/png;base64,BBBB'
    });
    const root = document.documentElement;
    expect(root.style.getPropertyValue('--bg-image')).toContain('data:image/png;base64,BBBB');
    expect(presetClasses()).toEqual([]);
  });

  it('关闭背景时清掉图片与预设，且 data-bg 变 off', () => {
    // 这一条守的是「关掉背景后仍显示上一张图」：只把 data-bg 设成 off 而不清
    // --bg-image，切换回来的瞬间会闪出旧图
    applyBackground({ ...DEFAULT_BACKGROUND, kind: 'image', imageDataUrl: 'data:image/png;base64,CCCC' });
    applyBackground({ ...DEFAULT_BACKGROUND, kind: 'none' });
    const root = document.documentElement;
    expect(root.dataset.bg).toBe('off');
    expect(root.style.getPropertyValue('--bg-image')).toBe('');
    expect(presetClasses()).toEqual([]);
  });
});

describe('store 动作', () => {
  it('setPreset 同时把 kind 切到 preset 并落盘', () => {
    useBackgroundStore.getState().setPreset('sand');
    const s = useBackgroundStore.getState();
    expect(s.kind).toBe('preset');
    expect(s.presetId).toBe('sand');
    expect(JSON.parse(localStorage.getItem(STORAGE_KEY)!).presetId).toBe('sand');
  });

  it('setImage 记录图片并落盘', () => {
    useBackgroundStore.getState().setImage('data:image/jpeg;base64,DDDD');
    expect(useBackgroundStore.getState().kind).toBe('image');
    expect(JSON.parse(localStorage.getItem(STORAGE_KEY)!).imageDataUrl).toContain('DDDD');
  });

  it('reset 回到默认并落盘', () => {
    useBackgroundStore.getState().setPreset('ink');
    useBackgroundStore.getState().reset();
    const s = useBackgroundStore.getState();
    expect(s.kind).toBe('none');
    expect(s.presetId).toBe(DEFAULT_BACKGROUND.presetId);
    expect(JSON.parse(localStorage.getItem(STORAGE_KEY)!).kind).toBe('none');
  });

  it('localStorage 抛异常时不打断操作', () => {
    // 隐私模式 / 配额满：背景是装饰，绝不能让存储失败冒泡成一次崩溃
    const spy = vi.spyOn(Storage.prototype, 'setItem').mockImplementation(() => {
      throw new Error('QuotaExceededError');
    });
    expect(() => useBackgroundStore.getState().setDim(55)).not.toThrow();
    expect(useBackgroundStore.getState().dim).toBe(55);
    spy.mockRestore();
  });
});

describe('上限常量', () => {
  it('图片上限留足 localStorage 余量', () => {
    // 典型 localStorage 配额 5MB；超过一半就很容易与其它键一起写爆
    expect(MAX_DATA_URL_BYTES).toBeGreaterThan(100_000);
    expect(MAX_DATA_URL_BYTES).toBeLessThan(5_000_000 / 2);
  });
});