LocalNetMsg/scripts/selftest/electron-stub.cjs

// 无头测试用的 electron 桩: 只提供 src/main 里真正用到的 API
// (app.getPath / app.getVersion / BrowserWindow / ipcMain / shell ...)
const os = require('node:os')
const path = require('node:path')
const fs = require('node:fs')

const root = process.env.LNM_SELFTEST_HOME || path.join(os.tmpdir(), 'lnm-selftest')
fs.mkdirSync(root, { recursive: true })

function ensure(p) {
  fs.mkdirSync(p, { recursive: true })
  return p
}

// ---- nativeImage / clipboard 桩 ----
//
// 真的 Electron 用 Chromium 的图片解码器。桩里只按**魔数**认 PNG/JPEG (别的格式
// 一律给空图, 和真实现一样), 尺寸和编码后体积按**源文件大小**等比给 —— 目的不是
// 还原真图, 而是让自测能确定性地覆盖 "选 PNG 还是 JPEG / 降级重缩 / 复制" 这几条分支。
function emptyImage() {
  return {
    isEmpty: () => true,
    getSize: () => ({ width: 0, height: 0 }),
    resize: () => emptyImage(),
    toPNG: () => Buffer.alloc(0),
    toJPEG: () => Buffer.alloc(0),
    toDataURL: () => '',
  }
}

function fakeImage(opts) {
  const { width, height, pngSize, jpegSize } = opts
  return {
    isEmpty: () => false,
    getSize: () => ({ width, height }),
    resize: (o) => fakeImage({
      width: o.width || width,
      height: Math.round(height * ((o.width || width) / width)),
      pngSize,
      jpegSize,
    }),
    toPNG: () => Buffer.alloc(pngSize, 0x89),
    toJPEG: (q) => Buffer.alloc(Math.round(jpegSize * ((q == null ? 80 : q) / 80)), 0xff),
    toDataURL: () => 'data:image/png;base64,' + Buffer.alloc(32, 1).toString('base64'),
  }
}

function sniffImage(p) {
  try {
    const fd = fs.openSync(p, 'r')
    const buf = Buffer.alloc(8)
    fs.readSync(fd, buf, 0, 8, 0)
    fs.closeSync(fd)
    if (buf[0] === 0x89 && buf[1] === 0x50 && buf[2] === 0x4e && buf[3] === 0x47) return 'png'
    if (buf[0] === 0xff && buf[1] === 0xd8 && buf[2] === 0xff) return 'jpeg'
    return null
  } catch {
    return null
  }
}

function fakeImageForPath(p) {
  const size = fs.statSync(p).size
  return fakeImage({
    width: 1200, height: 900,
    // PNG 通常比源文件还大 (照片尤其), JPEG 大约三成 —— 够触发不同分支
    pngSize: Math.round(size * 1.5),
    jpegSize: Math.round(size * 0.3),
  })
}

const clipboardState = { image: null, text: '' }

module.exports = {
  app: {
    isPackaged: false,
    getPath(name) {
      if (name === 'userData') return ensure(path.join(root, 'userData'))
      if (name === 'documents') return ensure(path.join(root, 'documents'))
      if (name === 'downloads') return ensure(path.join(root, 'downloads'))
      if (name === 'home') return os.homedir()
      return ensure(path.join(root, name))
    },
    getVersion: () => '0.1.0',
    getName: () => 'local-net-msg',
    getAppPath: () => process.cwd(),
    on: () => {},
    once: () => {},
    whenReady: async () => {},
    quit: () => {},
  },
  BrowserWindow: class BrowserWindow {
    static getAllWindows() { return [] }
    static getFocusedWindow() { return null }
    isMinimized() { return false }
    restore() {}
    show() {}
    focus() {}
    webContents = { send: () => {} }
  },
  // 注意: 故意不提供 ipcRenderer —— electron-store 见到它会以为是渲染进程
  ipcMain: { on: () => {}, once: () => {}, handle: () => {}, removeHandler: () => {} },
  contextBridge: { exposeInMainWorld: () => {} },
  dialog: { showErrorBox: () => {}, showOpenDialog: async () => ({ canceled: true, filePaths: [] }) },
  shell: { openPath: async () => '', showItemInFolder: () => {} },
  Notification: class { static isSupported() { return false } constructor() {} show() {} },
  nativeImage: {
    createFromPath(p) {
      try {
        if (!fs.existsSync(p)) return emptyImage()
        if (!sniffImage(p)) return emptyImage()
        return fakeImageForPath(p)
      } catch {
        return emptyImage()
      }
    },
    createFromDataUrl(u) {
      // 只认 data:image/png;base64 和 data:image/jpeg;base64
      const m = /^data:image\/(png|jpeg);base64,/.exec(String(u || ''))
      if (!m) return emptyImage()
      return fakeImage({ width: 1200, height: 900, pngSize: 40_000, jpegSize: 12_000 })
    },
    createFromBuffer(b) {
      if (!b || b.length < 8) return emptyImage()
      const kind = b[0] === 0x89 && b[1] === 0x50 ? 'png' : (b[0] === 0xff && b[1] === 0xd8 ? 'jpeg' : null)
      if (!kind) return emptyImage()
      return fakeImage({
        width: 1200, height: 900,
        pngSize: Math.round(b.length * 1.5),
        jpegSize: Math.round(b.length * 0.3),
      })
    },
  },
  clipboard: {
    writeImage(img) { clipboardState.image = img },
    readImage() { return clipboardState.image },
    writeText(t) { clipboardState.text = String(t) },
    readText() { return clipboardState.text },
  },
  // 只给自测用: 看剪贴板里到底写进去了什么
  __clipboardState: clipboardState,
}