/**
 * styles.ts 单元测试
 * 覆盖 injectStyles / updateStyles / removeStyles
 */

import { injectStyles, updateStyles, removeStyles, getSystemTheme, watchSystemTheme } from '../src/styles';

describe('styles.ts - injectStyles', () => {
  afterEach(() => {
    removeStyles();
  });

  test('injectStyles 创建 <style> 元素', () => {
    injectStyles();
    const el = document.getElementById('metona-editor-styles');
    expect(el).not.toBeNull();
    expect(el!.tagName).toBe('STYLE');
  });

  test('injectStyles 重复调用不创建重复元素', () => {
    injectStyles();
    injectStyles();
    const els = document.querySelectorAll('#metona-editor-styles');
    expect(els.length).toBe(1);
  });

  test('注入的 CSS 包含编辑器样式规则', () => {
    injectStyles();
    const el = document.getElementById('metona-editor-styles');
    const css = el!.textContent || '';
    expect(css).toContain('.me-wrapper');
    expect(css).toContain('.me-toolbar');
    expect(css).toContain('.me-textarea');
    expect(css).toContain('.me-preview');
    expect(css).toContain('--md-bg');
    expect(css).toContain('--md-accent');
  });

  test('注入的 CSS 包含 RTL 规则', () => {
    injectStyles();
    const el = document.getElementById('metona-editor-styles');
    const css = el!.textContent || '';
    expect(css).toContain('[dir=rtl]');
  });

  test('注入的 CSS 包含打印样式', () => {
    injectStyles();
    const el = document.getElementById('metona-editor-styles');
    const css = el!.textContent || '';
    expect(css).toContain('@media print');
  });

  test('注入的 CSS 包含 reduced-motion', () => {
    injectStyles();
    const el = document.getElementById('metona-editor-styles');
    const css = el!.textContent || '';
    expect(css).toContain('prefers-reduced-motion');
  });
});

describe('styles.ts - updateStyles', () => {
  afterEach(() => {
    removeStyles();
  });

  test('updateStyles 更新已注入的样式', () => {
    injectStyles();
    const el = document.getElementById('metona-editor-styles')!;
    const original = el.textContent;
    updateStyles();
    expect(el.textContent).toBe(original); // 内容一致
  });

  test('updateStyles 在未注入时自动注入', () => {
    removeStyles();
    expect(document.getElementById('metona-editor-styles')).toBeNull();
    updateStyles();
    expect(document.getElementById('metona-editor-styles')).not.toBeNull();
  });
});

describe('styles.ts - removeStyles', () => {
  test('removeStyles 移除样式元素', () => {
    injectStyles();
    expect(document.getElementById('metona-editor-styles')).not.toBeNull();
    removeStyles();
    expect(document.getElementById('metona-editor-styles')).toBeNull();
  });

  test('removeStyles 重复调用不抛错', () => {
    removeStyles();
    expect(() => removeStyles()).not.toThrow();
  });
});

describe('styles.ts - getSystemTheme', () => {
  test('返回 light 或 dark', () => {
    const theme = getSystemTheme();
    expect(['light', 'dark']).toContain(theme);
  });
});

describe('styles.ts - watchSystemTheme', () => {
  test('返回取消函数', () => {
    const unsub = watchSystemTheme(() => {});
    expect(typeof unsub).toBe('function');
    unsub();
  });
});