fix: v0.2.4 健壮性与体验打磨 - 读取容错、10MB 大文件防护、横向滚动同步、Esc/外点关闭、二进制预警

src/main/index.ts

@@ -1,5 +1,5 @@
 import { join } from 'path'
-import { app, shell, BrowserWindow, Menu, ipcMain, dialog } from 'electron'
+import { app, shell, BrowserWindow, Menu, ipcMain, dialog, clipboard } from 'electron'
 import { electronApp, optimizer, is } from '@electron-toolkit/utils'
 import iconv from 'iconv-lite'
 import fs from 'fs'
@@ -41,27 +41,50 @@ function createWindow(): void {
   }
 }
 
+/** 单侧文件大小上限（10MB）：超限直接拦截，避免超大文件卡死界面 */
+const MAX_FILE_SIZE = 10 * 1024 * 1024
+
+/**
+ * 缓冲区二进制启发式判定：出现 NUL 字节立即判定；
+ * 否则统计前 8KB 内不可见控制字符占比（> 5% 视为二进制）。
+ */
+function looksBinary(buf: Buffer): boolean {
+  const len = Math.min(buf.length, 8000)
+  if (len === 0) return false
+  let suspicious = 0
+  for (let i = 0; i < len; i++) {
+    const b = buf[i]
+    if (b === 0) return true
+    if (b < 0x09 || (b > 0x0d && b < 0x20)) suspicious++
+  }
+  return suspicious / len > 0.05
+}
+
 /**
  * 探测文本编码：优先 BOM，其次严格 UTF-8，
- * 失败则回退 GBK 解码，返回 { text, encoding }。
+ * 失败则回退 GBK 解码，返回 { text, encoding, binary }。
  */
-function decodeText(buf: Buffer): { text: string; encoding: string } {
+function decodeText(buf: Buffer): { text: string; encoding: string; binary: boolean } {
   if (buf.length >= 3 && buf[0] === 0xef && buf[1] === 0xbb && buf[2] === 0xbf) {
-    return { text: buf.subarray(3).toString('utf8'), encoding: 'UTF-8 (BOM)' }
+    return { text: buf.subarray(3).toString('utf8'), encoding: 'UTF-8 (BOM)', binary: false }
   }
   if (buf.length >= 2 && buf[0] === 0xfe && buf[1] === 0xff) {
-    return { text: iconv.decode(buf.subarray(2), 'utf16-be'), encoding: 'UTF-16 BE' }
+    return { text: iconv.decode(buf.subarray(2), 'utf16-be'), encoding: 'UTF-16 BE', binary: false }
   }
   if (buf.length >= 2 && buf[0] === 0xff && buf[1] === 0xfe) {
-    return { text: buf.subarray(2).toString('utf16le'), encoding: 'UTF-16 LE' }
+    return { text: buf.subarray(2).toString('utf16le'), encoding: 'UTF-16 LE', binary: false }
   }
   // 严格 UTF-8 探测
   try {
     const decoder = new TextDecoder('utf-8', { fatal: true })
     const text = decoder.decode(buf)
-    return { text, encoding: 'UTF-8' }
+    return { text, encoding: 'UTF-8', binary: false }
   } catch {
-    return { text: iconv.decode(buf, 'gbk'), encoding: 'GBK' }
+    const text = iconv.decode(buf, 'gbk')
+    // GBK 覆盖面广，二进制内容也能解出“文字”；用字节启发式 + 替换符占比双保险
+    const bad = (text.match(/\uFFFD/g) ?? []).length
+    const binary = looksBinary(buf) || (text.length > 0 && bad / text.length > 0.05)
+    return { text, encoding: 'GBK', binary }
   }
 }
 
@@ -76,10 +99,19 @@ ipcMain.handle('file:open', async (_event, side: 'left' | 'right' | null) => {
   })
   if (result.canceled || result.filePaths.length === 0) return null
   const filePath = result.filePaths[0]
-  const buf = fs.readFileSync(filePath)
-  const { text, encoding } = decodeText(buf)
   const name = filePath.split(/[\\/]/).pop() ?? filePath
-  return { path: filePath, name, text, encoding }
+  let buf: Buffer
+  try {
+    const stat = fs.statSync(filePath)
+    if (stat.size > MAX_FILE_SIZE) {
+      return { error: 'too-large', name, size: stat.size }
+    }
+    buf = fs.readFileSync(filePath)
+  } catch {
+    return { error: 'read-failed', name }
+  }
+  const { text, encoding, binary } = decodeText(buf)
+  return { path: filePath, name, text, encoding, binary }
 })
 
 /** IPC: 解码拖拽传入的原始字节（复用编码探测逻辑） */
@@ -111,7 +143,7 @@ ipcMain.handle('file:show-in-folder', (_event, filePath: string) => {
 
 /** IPC: 复制文本到剪贴板 */
 ipcMain.handle('clipboard:write', (_event, text: string) => {
-  require('electron').clipboard.writeText(text)
+  clipboard.writeText(text)
   return true
 })