import { test, expect } from '@playwright/test'
import { readFile } from 'fs/promises'
import { join } from 'path'
import {
  launchApp,
  stubOpenDialogSeq,
  stubSaveDialog,
  makeTmpDir,
  removeTmpDir,
  writeTextFixture,
  pasteText
} from './helpers'

/**
 * DiffLens E2E 主链路验收（对 build 产物运行真实 Electron）：
 * 覆盖 jsdom 单测无法触达的主进程解码 / 报告写盘 / 剪贴板 IPC / 偏好持久化生命周期。
 * 运行前必须先 npm run build。
 */

test.describe('启动与基础交互', () => {
  test('应用启动：窗口标题与双空态面板', async () => {
    const { app, window } = await launchApp()
    await expect(window).toHaveTitle('DiffLens')
    await expect(window.getByText('选择左侧文件')).toBeVisible()
    await expect(window.getByText('选择右侧文件')).toBeVisible()
    // 空态不出现导出入口
    await expect(window.getByRole('button', { name: '导出报告' })).toHaveCount(0)
    await app.close()
  })

  test('粘贴两侧文本：差异渲染与统计徽章', async () => {
    const { app, window } = await launchApp()
    await pasteText(window, 'left', 'alpha\nbeta\ngamma')
    await expect(window.getByRole('button', { name: '导出报告' })).toBeVisible()
    await pasteText(window, 'right', 'alpha\nBETA\ngamma')
    // 差异徽章与状态栏结论
    await expect(window.getByText('有差异')).toBeVisible()
    await expect(window.getByText('~1')).toBeVisible()
    // 修改行内容渲染（词级高亮行；exact 避免大小写不敏感的重复命中）
    await expect(window.getByText('beta', { exact: true })).toBeVisible()
    await expect(window.getByText('BETA', { exact: true })).toBeVisible()
    await app.close()
  })
})

test.describe('文件打开与编码识别（主进程真实解码链路）', () => {
  let dir: string

  test.beforeAll(async () => {
    dir = await makeTmpDir('difflens-e2e-enc-')
  })

  test.afterAll(async () => {
    await removeTmpDir(dir)
  })

  test('打开 GBK 与 UTF-8 BOM 文件：编码标注与内容正确渲染', async () => {
    const gbkPath = await writeTextFixture(
      dir,
      'gbk.txt',
      '中文内容第一行\n第二行数据',
      'gbk'
    )
    const bomPath = await writeTextFixture(dir, 'bom.txt', 'BOM 首行\nBOM 第二行', 'utf8-bom')
    const { app, window } = await launchApp()
    await stubOpenDialogSeq(app, [[gbkPath], [bomPath]])
    await window.getByRole('button', { name: '打开左侧' }).click()
    await expect(window.getByText('中文内容第一行')).toBeVisible()
    await window.getByRole('button', { name: '打开右侧' }).click()
    await expect(window.getByText('BOM 首行')).toBeVisible()
    // 面板头编码标注（主进程探测结果；exact 避免文件名 gbk.txt 的子串误匹配）
    await expect(window.locator('.pane-meta').filter({ hasText: 'GBK' })).toBeVisible()
    await expect(window.locator('.pane-meta').filter({ hasText: 'UTF-8 (BOM)' })).toBeVisible()
    await app.close()
  })

  test('大体积 GBK 文件：后台 worker 解码后完整渲染', async () => {
    // 约 300KB（≥ 解码 worker 快路径阈值 256KB）：走 worker_threads 后台解码链路
    const bigLines = Array.from({ length: 15000 }, (_, i) => `中文大文件行${i}数据`).join('\n')
    const bigPath = await writeTextFixture(dir, 'big-gbk.txt', bigLines, 'gbk')
    const { app, window } = await launchApp()
    await stubOpenDialogSeq(app, [[bigPath]])
    await window.getByRole('button', { name: '打开左侧' }).click()
    // 首行在视口内；末行在虚拟滚动视口外，以状态栏总行数断言完整性
    await expect(window.getByText('中文大文件行0数据')).toBeVisible()
    await expect(window.locator('.status-item').filter({ hasText: '15000 行' })).toBeVisible()
    await expect(window.locator('.pane-meta').filter({ hasText: 'GBK' })).toBeVisible()
    await app.close()
  })
})

test.describe('比较选项端到端', () => {
  test('忽略大小写与忽略所有空白组合生效', async () => {
    const { app, window } = await launchApp()
    await pasteText(window, 'left', 'alpha\nbeta')
    await pasteText(window, 'right', 'ALPHA\n beta')
    // 默认严格对比：两处差异
    await expect(window.getByText('有差异')).toBeVisible()
    // 仅忽略大小写：仍有行首空白差异
    await window.getByLabel('忽略大小写').check()
    await expect(window.getByText('有差异')).toBeVisible()
    // 再忽略所有空白：判为完全一致
    await window.getByLabel('忽略所有空白').check()
    await expect(window.getByText('两文件内容完全一致')).toBeVisible()
    await app.close()
  })

  test('字符级对比：跨行重组判为一致', async () => {
    const { app, window } = await launchApp()
    await pasteText(window, 'left', 'ab cd')
    await pasteText(window, 'right', 'ab\ncd')
    await expect(window.getByText('有差异')).toBeVisible()
    await window.getByLabel('字符级对比').check()
    await expect(window.getByText('两文件内容完全一致')).toBeVisible()
    await app.close()
  })
})

test.describe('差异导航与视图', () => {
  test('F7 / Shift+F7 导航与仅看差异折叠', async () => {
    const { app, window } = await launchApp()
    await pasteText(window, 'left', 'a\nX1\nb\nY1\nc')
    await pasteText(window, 'right', 'a\nX2\nb\nY2\nc')
    await expect(window.getByText('1 / 2')).toBeVisible()
    await window.keyboard.press('F7')
    await expect(window.getByText('2 / 2')).toBeVisible()
    await window.keyboard.press('Shift+F7')
    await expect(window.getByText('1 / 2')).toBeVisible()
    // 仅看差异：未更改行折叠为提示行
    await window.getByLabel('仅看差异').check()
    await expect(window.getByText(/已折叠/).first()).toBeVisible()
    await app.close()
  })

  test('交换左右侧后面板文件互换', async () => {
    const dir = await makeTmpDir('difflens-e2e-swap-')
    try {
      const aPath = await writeTextFixture(dir, 'a.txt', 'aaa')
      const bPath = await writeTextFixture(dir, 'b.txt', 'bbb')
      const { app, window } = await launchApp()
      await stubOpenDialogSeq(app, [[aPath], [bPath]])
      await window.getByRole('button', { name: '打开左侧' }).click()
      await expect(window.locator('.pane-file').filter({ hasText: 'a.txt' })).toBeVisible()
      await window.getByRole('button', { name: '打开右侧' }).click()
      await expect(window.locator('.pane-file').filter({ hasText: 'b.txt' })).toBeVisible()
      await window.getByRole('button', { name: '⇄ 交换左右' }).click()
      // 面板头文件名互换（用 .pane-file 定位，避免与状态栏文件名混淆）
      const paneFiles = window.locator('.pane-file')
      await expect(paneFiles.nth(0)).toHaveText(/b\.txt/)
      await expect(paneFiles.nth(1)).toHaveText(/a\.txt/)
      await app.close()
    } finally {
      await removeTmpDir(dir)
    }
  })
})

test.describe('报告导出（主进程写盘链路）', () => {
  test('导出 HTML 报告：文件落盘且包含结论', async () => {
    const dir = await makeTmpDir('difflens-e2e-report-')
    try {
      const { app, window } = await launchApp()
      await pasteText(window, 'left', 'same\ndiff-left')
      await pasteText(window, 'right', 'same\ndiff-right')
      const savePath = join(dir, 'report.html')
      await stubSaveDialog(app, savePath)
      await window.getByRole('button', { name: '导出报告' }).click()
      await window.getByRole('button', { name: 'HTML 报告' }).click()
      await expect(window.getByText(/报告已保存/)).toBeVisible()
      const html = await readFile(savePath, 'utf-8')
      expect(html).toContain('<!doctype html>')
      expect(html).toContain('共 1 处不同：修改 1 行')
      // 统计卡与未更改行渲染（diff-left 被词级高亮拆分 span，不作整串断言）
      expect(html).toContain('~1')
      expect(html).toContain('same')
      await app.close()
    } finally {
      await removeTmpDir(dir)
    }
  })
})

test.describe('文件夹对比（主进程真实扫描链路）', () => {
  test('选择两个文件夹：状态判定、过滤与双击进入单文件对比', async () => {
    const root = await makeTmpDir('difflens-e2e-folder-')
    try {
      const leftDir = join(root, 'left')
      const rightDir = join(root, 'right')
      const { mkdir, writeFile: wf } = await import('fs/promises')
      await mkdir(join(leftDir, 'sub'), { recursive: true })
      await mkdir(join(rightDir, 'sub'), { recursive: true })
      await wf(join(leftDir, 'same.txt'), 'identical')
      await wf(join(rightDir, 'same.txt'), 'identical')
      await wf(join(leftDir, 'diff.txt'), 'left content\nsame tail')
      await wf(join(rightDir, 'diff.txt'), 'right content\nsame tail')
      await wf(join(leftDir, 'only-left.txt'), 'L')
      await wf(join(leftDir, 'sub', 'nested.txt'), 'nested L')
      await wf(join(rightDir, 'sub', 'nested.txt'), 'nested R')

      const { app, window } = await launchApp()
      await stubOpenDialogSeq(app, [[leftDir], [rightDir]])
      await window.getByRole('button', { name: '对比文件夹' }).click()

      // 文件夹模式：路径卡片与统计徽章
      await expect(window.getByText('相同 1')).toBeVisible()
      await expect(window.getByText('不同 2')).toBeVisible()
      await expect(window.getByText('仅左 1')).toBeVisible()
      // 默认仅看差异：same.txt 被过滤，差异条目可见
      await expect(window.getByText('diff.txt')).toBeVisible()
      await expect(window.getByText('sub/nested.txt')).toBeVisible()
      await expect(window.getByText('same.txt')).toHaveCount(0)

      // 双击差异条目进入单文件对比
      await window.getByText('diff.txt').dblclick()
      await expect(window.getByText('left content')).toBeVisible()
      await expect(window.getByText('right content')).toBeVisible()
      await expect(window.getByText('有差异')).toBeVisible()
      await expect(window.getByRole('button', { name: '← 返回文件夹对比' })).toBeVisible()

      // 返回文件夹列表（扫描结果保留）
      await window.getByRole('button', { name: '← 返回文件夹对比' }).click()
      await expect(window.getByText('相同 1')).toBeVisible()
      await expect(window.getByText('diff.txt')).toBeVisible()
      await app.close()
    } finally {
      await removeTmpDir(root)
    }
  })
})

test.describe('偏好持久化（跨实例重启）', () => {
  test('重启后恢复比较选项与视图开关', async () => {
    // 第一实例 fresh 清掉历史残留，建立干净基线后再写入偏好
    const first = await launchApp({ fresh: true })
    await pasteText(first.window, 'left', 'alpha')
    await first.window.getByLabel('忽略大小写').check()
    await first.window.getByLabel('仅看差异').check()
    await expect(first.window.getByLabel('忽略大小写')).toBeChecked()
    // 等 localStorage 写回完成再关闭
    await first.window.waitForTimeout(500)
    await first.app.close()

    // 同一 userData 下重启（不清理）：偏好应恢复
    const second = await launchApp({ fresh: false })
    await pasteText(second.window, 'left', 'alpha')
    await expect(second.window.getByLabel('忽略大小写')).toBeChecked()
    await expect(second.window.getByLabel('仅看差异')).toBeChecked()
    await second.app.close()
  })
})