From 05e7025015da7974a65db7f767a870fafe218b86 Mon Sep 17 00:00:00 2001
From: Amp <amp@ampcode.com>
Date: Wed, 12 Aug 2026 06:53:05 +0000
Subject: [PATCH] refactor(infra): flatten LAN route hint resolution

Amp-Thread-ID: https://ampcode.com/threads/T-019ff438-3b93-77b8-9828-1d3c586cb127
---
 src/infra/advertised-lan-host.ts | 53 +++++++++++++-------------------
 1 file changed, 21 insertions(+), 32 deletions(-)

diff --git a/src/infra/advertised-lan-host.ts b/src/infra/advertised-lan-host.ts
index ba879f2e445d..8896a0306fcd 100644
--- a/src/infra/advertised-lan-host.ts
+++ b/src/infra/advertised-lan-host.ts
@@ -186,41 +186,30 @@ async function resolveDefaultRouteHints(params: {
   runCommandWithTimeout: AdvertisedLanHostCommandRunner;
   timeoutMs: number;
 }): Promise<AdvertisedLanRouteHint[]> {
+  let argv: string[];
+  let parse: typeof parseWindowsDefaultRouteHints;
   if (params.platform === "win32") {
-    const stdout = await runRouteHintCommand(
-      params.runCommandWithTimeout,
-      [
-        "powershell.exe",
-        "-NoProfile",
-        "-ExecutionPolicy",
-        "Bypass",
-        "-Command",
-        WINDOWS_DEFAULT_ROUTE_COMMAND,
-      ],
-      params.timeoutMs,
-    );
-    return stdout ? parseWindowsDefaultRouteHints(stdout) : [];
+    argv = [
+      "powershell.exe",
+      "-NoProfile",
+      "-ExecutionPolicy",
+      "Bypass",
+      "-Command",
+      WINDOWS_DEFAULT_ROUTE_COMMAND,
+    ];
+    parse = parseWindowsDefaultRouteHints;
+  } else if (params.platform === "darwin") {
+    argv = ["route", "-n", "get", "default"];
+    parse = parseMacOsDefaultRouteHints;
+  } else if (params.platform === "linux") {
+    argv = ["ip", "-4", "route", "show", "default"];
+    parse = parseLinuxDefaultRouteHints;
+  } else {
+    return [];
   }
 
-  if (params.platform === "darwin") {
-    const stdout = await runRouteHintCommand(
-      params.runCommandWithTimeout,
-      ["route", "-n", "get", "default"],
-      params.timeoutMs,
-    );
-    return stdout ? parseMacOsDefaultRouteHints(stdout) : [];
-  }
-
-  if (params.platform === "linux") {
-    const stdout = await runRouteHintCommand(
-      params.runCommandWithTimeout,
-      ["ip", "-4", "route", "show", "default"],
-      params.timeoutMs,
-    );
-    return stdout ? parseLinuxDefaultRouteHints(stdout) : [];
-  }
-
-  return [];
+  const stdout = await runRouteHintCommand(params.runCommandWithTimeout, argv, params.timeoutMs);
+  return stdout ? parse(stdout) : [];
 }
 
 export async function resolveAdvertisedLanHostCore(