fix: handle failures in the PAC server, Gist sync and floating window (#2032)

- The PAC server called listen() with no 'error' listener. A host the user
  cannot bind to - or a port already in use - emitted an unhandled 'error'
  event, which in Node terminates the process, so a bad PAC host setting
  crashed the whole main process. Attach an error handler and surface the
  failure to the caller.

- The Gist upload never checked the HTTP status. Once the token expired,
  GitHub answered 401 and the code still recorded the runtime config as
  successfully synced, so the user saw a healthy backup that did not
  exist. Check the status and report the failure.

- On 'render-process-gone' the floating window handler only set the module
  reference to null without destroying the BrowserWindow. The dead window
  stayed on screen, always-on-top, with nothing left holding a reference
  to close it. Destroy it before clearing the reference.

src/main/resolve/floatingWindow.ts

@@ -54,13 +54,26 @@ async function createFloatingWindow(): Promise<void> {
       }
     }
 
-    floatingWindow = new BrowserWindow(windowOptions)
+    const win = new BrowserWindow(windowOptions)
+    floatingWindow = win
     floatingWindowState.manage(floatingWindow)
 
     // 事件监听器
     floatingWindow.webContents.on('render-process-gone', (_, details) => {
       logError('Render process gone', details.reason)
-      floatingWindow = null
+      // 只丢引用不销毁的话，屏幕上会残留一个无边框、置顶、不在任务栏且 closable: false 的幽灵窗，
+      // 用户既关不掉也找不到，只能重启应用
+      if (!win.isDestroyed()) {
+        win.destroy()
+      }
+    })
+
+    // 窗口销毁后必须清掉引用，否则 isVisible() 之类的调用会作用在已销毁窗口上抛错；
+    // 判断 win 是为了避免旧窗口的 closed 事件把新建窗口的引用清掉
+    win.on('closed', () => {
+      if (floatingWindow === win) {
+        floatingWindow = null
+      }
     })
 
     floatingWindow.on('ready-to-show', () => {

src/main/resolve/gistApi.ts

@@ -30,6 +30,15 @@ function hashRuntimeConfig(runtimeConfig: string): string {
   return createHash('sha256').update(runtimeConfig).digest('hex')
 }
 
+// chromeRequest 对任何状态码都会 resolve，不校验状态码的话 token 失效（401/403）会被当成成功：
+// 错误响应体被当作「远端没有这个 gist」，上传也「成功」，哈希被记为已同步后就再也不会重试
+function assertGithubOk(res: chromeRequest.Response, action: string): void {
+  if (res.status < 200 || res.status >= 300) {
+    const detail = typeof res.data === 'string' ? res.data : JSON.stringify(res.data)
+    throw new Error(`GitHub API ${action} failed with status ${res.status}: ${detail}`)
+  }
+}
+
 async function listGists(token: string): Promise<GistInfo[]> {
   const { 'mixed-port': port = DEFAULT_MIHOMO_PORTS.mixed } = await getControledMihomoConfig()
   const res = await chromeRequest.get('https://api.github.com/gists', {
@@ -45,12 +54,13 @@ async function listGists(token: string): Promise<GistInfo[]> {
     },
     responseType: 'json'
   })
+  assertGithubOk(res, 'list gists')
   return Array.isArray(res.data) ? res.data : []
 }
 
 async function createGist(token: string, content: string): Promise<void> {
   const { 'mixed-port': port = DEFAULT_MIHOMO_PORTS.mixed } = await getControledMihomoConfig()
-  await chromeRequest.post(
+  const res = await chromeRequest.post(
     'https://api.github.com/gists',
     {
       description: 'Auto Synced Clash Party Runtime Config',
@@ -70,11 +80,12 @@ async function createGist(token: string, content: string): Promise<void> {
       }
     }
   )
+  assertGithubOk(res, 'create gist')
 }
 
 async function updateGist(token: string, id: string, content: string): Promise<void> {
   const { 'mixed-port': port = DEFAULT_MIHOMO_PORTS.mixed } = await getControledMihomoConfig()
-  await chromeRequest.patch(
+  const res = await chromeRequest.patch(
     `https://api.github.com/gists/${id}`,
     {
       description: 'Auto Synced Clash Party Runtime Config',
@@ -93,6 +104,7 @@ async function updateGist(token: string, id: string, content: string): Promise<v
       }
     }
   )
+  assertGithubOk(res, 'update gist')
 }
 
 export async function getGistUrl(): Promise<string> {

src/main/resolve/server.ts

@@ -11,7 +11,7 @@ import * as chromeRequest from '../utils/chromeRequest'
 import subStoreIcon from '../../../resources/subStoreIcon.png?asset'
 import { dataDir, mihomoWorkDir, subStoreDir, substoreLogPath } from '../utils/dirs'
 import { getAppConfig, getControledMihomoConfig } from '../config'
-import { systemLogger } from '../utils/logger'
+import { proxyLogger, systemLogger } from '../utils/logger'
 import { createCappedLogWritableStream } from '../utils/logFile'
 import { DEFAULT_MIHOMO_PORTS, DEFAULT_USE_SUB_STORE } from '../../shared/appConfig'
 
@@ -46,7 +46,7 @@ export function findAvailablePort(startPort: number): Promise<number> {
   })
 }
 
-let pacServer: http.Server
+let pacServer: http.Server | undefined
 
 export async function startPacServer(): Promise<void> {
   await stopPacServer()
@@ -60,17 +60,37 @@ export async function startPacServer(): Promise<void> {
   const { 'mixed-port': port = DEFAULT_MIHOMO_PORTS.mixed } = await getControledMihomoConfig()
   script = script.replaceAll('%mixed-port%', port.toString())
   pacPort = await findAvailablePort(10000)
-  pacServer = http
-    .createServer(async (_req, res) => {
-      res.writeHead(200, { 'Content-Type': 'application/x-ns-proxy-autoconfig' })
-      res.end(script)
-    })
-    .listen(pacPort, host)
+  const server = http.createServer(async (_req, res) => {
+    res.writeHead(200, { 'Content-Type': 'application/x-ns-proxy-autoconfig' })
+    res.end(script)
+  })
+  // host 由用户自由填写，findAvailablePort 只在 127.0.0.1 上探测过端口，这里绑定可能失败
+  // （EADDRNOTAVAIL / ENOTFOUND）。listen 失败是异步事件，没有 'error' 监听器会直接变成主进程
+  // 未捕获异常并弹错误框，所以把失败转成 reject 交给调用方处理
+  await new Promise<void>((resolve, reject) => {
+    const onError = (err: Error): void => {
+      server.removeListener('listening', onListening)
+      reject(err)
+    }
+    const onListening = (): void => {
+      server.removeListener('error', onError)
+      // 监听成功后仍保留 error 监听，防止运行期出错（如网络接口变化）再次崩溃主进程
+      server.on('error', (err) => {
+        proxyLogger.error('PAC server error', err).catch(() => {})
+      })
+      resolve()
+    }
+    server.once('error', onError)
+    server.once('listening', onListening)
+    server.listen(pacPort, host)
+  })
+  pacServer = server
 }
 
 export async function stopPacServer(): Promise<void> {
   if (pacServer) {
     pacServer.close()
+    pacServer = undefined
   }
 }