From 2d7d6e1357411787e15346c0da69aaff2a7a278a Mon Sep 17 00:00:00 2001
From: kari-ts <135075563+kari-ts@users.noreply.github.com>
Date: Tue, 7 May 2024 12:44:27 -0700
Subject: [PATCH] IpnViewModel: reset vpn state before login/reauth (#366)

Fixes ENG-3479

Clear routes when switching profiles and reauthenticating. This fixes an issue where previously set routes/DNS configs caused actions to fail.

Signed-off-by: kari-ts <kari@tailscale.com>
---
 .../ipn/ui/viewModel/IpnViewModel.kt          | 25 ++++++++++++++++---
 1 file changed, 21 insertions(+), 4 deletions(-)

diff --git a/android/src/main/java/com/tailscale/ipn/ui/viewModel/IpnViewModel.kt b/android/src/main/java/com/tailscale/ipn/ui/viewModel/IpnViewModel.kt
index 9f7e0e9..7b19b32 100644
--- a/android/src/main/java/com/tailscale/ipn/ui/viewModel/IpnViewModel.kt
+++ b/android/src/main/java/com/tailscale/ipn/ui/viewModel/IpnViewModel.kt
@@ -100,9 +100,19 @@ open class IpnViewModel : ViewModel() {
       }
     }
 
+    // Need to stop running before logging in to clear routes:
+    // https://linear.app/tailscale/issue/ENG-3441/routesdns-is-not-cleared-when-switching-profiles-or-reauthenticating
+    val stopThenLogin = {
+      Client(viewModelScope).editPrefs(Ipn.MaskedPrefs().apply { WantRunning = false }) { result ->
+        result
+            .onSuccess { loginAction() }
+            .onFailure { Log.e(TAG, "Error setting wantRunning to false: ${it.message}") }
+      }
+    }
+
     val startAction = {
       Client(viewModelScope).start(Ipn.Options(AuthKey = authKey)) { start ->
-        start.onFailure { completionHandler(Result.failure(it)) }.onSuccess { loginAction() }
+        start.onFailure { completionHandler(Result.failure(it)) }.onSuccess { stopThenLogin() }
       }
     }
 
@@ -164,9 +174,16 @@ open class IpnViewModel : ViewModel() {
   }
 
   fun switchProfile(profile: IpnLocal.LoginProfile, completionHandler: (Result<String>) -> Unit) {
-    Client(viewModelScope).switchProfile(profile) {
-      startVPN()
-      completionHandler(it)
+    val switchProfile = {
+      Client(viewModelScope).switchProfile(profile) {
+        startVPN()
+        completionHandler(it)
+      }
+    }
+    Client(viewModelScope).editPrefs(Ipn.MaskedPrefs().apply { WantRunning = false }) { result ->
+      result
+          .onSuccess { switchProfile() }
+          .onFailure { Log.e(TAG, "Error setting wantRunning to false: ${it.message}") }
     }
   }