fix(profiles): connection-profile switch re-dials the WebSocket (#888)

Co-authored-by: M57 <hy4ri@users.noreply.github.com>

app/src/main/java/com/m57/hermescontrol/data/local/AuthManager.kt

@@ -382,6 +382,11 @@ object AuthManager {
             ActiveSessionHolder.clear()
         }
         serverStore.update { it.copy(selectedProfileId = id) }
+        // Keep contextFlow truthful: the base URL resolves per selected
+        // profile, so a connection-profile switch must re-emit the NEW
+        // server's URL (previously stale — reactive consumers saw the old
+        // server's URL after a switch).
+        _baseUrlFlow.value = serverStore.getLatestState().resolvedBaseUrl
         _selectedProfileFlow.value = id
         synchronized(this) {
             tokenInitialized = false
@@ -416,7 +421,17 @@ object AuthManager {
     private fun normalizedProfileId(profileId: String?): String =
         profileId?.takeIf { it.isNotBlank() } ?: DEFAULT_PROFILE_ID
 
-    private suspend fun syncCookieStoreForProfile(profileId: String?) {
+    /**
+     * Swaps the cookie jar's ACTIVE store to the given profile's. Idempotent
+     * (no-op when the store is already active). Suspends because switching
+     * store reads/writes the encrypted prefs.
+     *
+     * Internal so the switch coordinator can AWAIT the swap before re-dialing
+     * the WebSocket — a dial that races it mints the WS ticket with the
+     * PREVIOUS server's cookie → 401 → dead socket (split-brain follow-up,
+     * reproduced live 2026-08-12).
+     */
+    internal suspend fun syncCookieStoreForProfile(profileId: String?) {
         if (!CookieManager.isInitialized()) return
         val normalizedId = normalizedProfileId(profileId)
         if (CookieManager.cookieJar.currentServer() != normalizedId) {
@@ -456,6 +471,7 @@ object AuthManager {
             appScope = null
         }
         _activeProfileId.value = null
+        _baseUrlFlow.value = ""
     }
 
     fun getToken(): String? {

app/src/main/java/com/m57/hermescontrol/data/session/ProfileSwitchCoordinator.kt

@@ -34,6 +34,9 @@ object ProfileSwitchCoordinator {
     private val _switched = MutableSharedFlow<String>(extraBufferCapacity = 1)
     val switched: SharedFlow<String> = _switched.asSharedFlow()
 
+    private val _connectionSwitched = MutableSharedFlow<String>(extraBufferCapacity = 1)
+    val connectionSwitched: SharedFlow<String> = _connectionSwitched.asSharedFlow()
+
     suspend fun switchProfile(name: String): NetworkResult<Unit> {
         val result =
             withContext(Dispatchers.IO) {
@@ -53,4 +56,40 @@ object ProfileSwitchCoordinator {
         }
         return result
     }
+
+    /**
+     * Switches the CONNECTION profile — which server the app talks to (e.g.
+     * LAN "default" vs a Tailscale host). Unlike [switchProfile] (which only
+     * re-scopes the SERVER-side Hermes profile over the same socket), this
+     * re-points Retrofit AND re-dials the WebSocket, because the socket stays
+     * glued to the old server otherwise: after a switch every REST tab talks
+     * to the new server while chat keeps streaming from the old gateway
+     * (split-brain reproduced live 2026-08-12 on the hyari emulator).
+     *
+     * Order matters:
+     *  1. Persist the LOCAL selection — the token cache, cookie scope and
+     *     [AuthManager.contextFlow] re-home to the new profile.
+     *  2. Rebuild Retrofit so REST targets the new server.
+     *  3. Emit [connectionSwitched] BEFORE the socket re-dial, so chat wipes
+     *     its stale conversation first; the re-dialed socket then delivers
+     *     gateway.ready → handleGatewayReady auto-creates a FRESH session on
+     *     the new server (desktop requestFreshSession parity).
+     *  4. Re-dial the WebSocket off the main thread (the ticket mint does
+     *     blocking I/O — NetworkOnMainThreadException otherwise).
+     */
+    suspend fun switchConnectionProfile(profileId: String?) {
+        AuthManager.setSelectedProfileId(profileId)
+        ApiClient.rebuild()
+        _connectionSwitched.emit(profileId.orEmpty())
+        withContext(Dispatchers.IO) {
+            // The WS ticket mint reads the cookie jar's ACTIVE store; the
+            // selection change swaps that store asynchronously, so a dial
+            // that races it mints with the PREVIOUS server's cookie → 401 →
+            // aborted socket with no retry. Await the swap before dialing
+            // (idempotent no-op when it already landed).
+            AuthManager.syncCookieStoreForProfile(profileId)
+            HermesWsClient.disconnect()
+            HermesWsClient.connect()
+        }
+    }
 }

app/src/main/java/com/m57/hermescontrol/ui/chat/ChatViewModel.kt

@@ -576,6 +576,16 @@ class ChatViewModel(
                     resetSessionState(sessionId = null, title = "Hermes", isLoading = true)
                 }
         }
+        // Same wipe when the CONNECTION profile changes (different server):
+        // without it, gateway.ready on the re-dialed socket tries to resume
+        // the OLD server's session on the NEW server and fails (split-brain
+        // after connection-profile switch, reproduced live 2026-08-12).
+        viewModelScope.launch {
+            ProfileSwitchCoordinator.connectionSwitched
+                .collect { _ ->
+                    resetSessionState(sessionId = null, title = "Hermes", isLoading = true)
+                }
+        }
         // Slash-command usage ranking (issue #865): mirror the local usage
         // counts into state so the autocomplete can surface most-used
         // commands first. Best-effort — the store never throws.

app/src/main/java/com/m57/hermescontrol/ui/settings/SettingsViewModel.kt

@@ -10,6 +10,7 @@ import com.m57.hermescontrol.data.remote.CleartextPolicy
 import com.m57.hermescontrol.data.remote.NetworkResult
 import com.m57.hermescontrol.data.remote.ServerEndpoint
 import com.m57.hermescontrol.data.remote.safeApiCall
+import com.m57.hermescontrol.data.session.ProfileSwitchCoordinator
 import com.m57.hermescontrol.data.ws.HermesWsClient
 import com.m57.hermescontrol.theme.ThemePreference
 import com.m57.hermescontrol.theme.ThemePreset
@@ -103,9 +104,13 @@ class SettingsViewModel(
     }
 
     fun selectProfile(profileId: String?) {
-        AuthManager.setSelectedProfileId(profileId)
-        viewModelScope.launch(ioDispatcher) { loadSettings() }
-        ApiClient.rebuild()
+        viewModelScope.launch(ioDispatcher) {
+            // The coordinator re-homes EVERYTHING: selection + Retrofit +
+            // WebSocket re-dial, so chat doesn't stay glued to the previous
+            // server (issue: split-brain after connection-profile switch).
+            ProfileSwitchCoordinator.switchConnectionProfile(profileId)
+            loadSettings()
+        }
     }
 
     fun deleteProfile(profileId: String) {
@@ -114,14 +119,25 @@ class SettingsViewModel(
         AuthManager.setProfileToken(profileId, null)
         // Never leave selection null (issue #478): if the deleted profile was selected,
         // fall back to the default profile instead of clearing selection.
-        if (AuthManager.getSelectedProfileId() == profileId) {
-            if (updatedProfiles.none { it.id == AuthManager.DEFAULT_PROFILE_ID }) {
-                AuthManager.ensureDefaultProfile()
+        val reselectDefault =
+            if (AuthManager.getSelectedProfileId() == profileId) {
+                if (updatedProfiles.none { it.id == AuthManager.DEFAULT_PROFILE_ID }) {
+                    AuthManager.ensureDefaultProfile()
+                }
+                true
+            } else {
+                false
             }
-            AuthManager.setSelectedProfileId(AuthManager.DEFAULT_PROFILE_ID)
+        viewModelScope.launch(ioDispatcher) {
+            if (reselectDefault) {
+                // Same re-home as a manual switch: the WebSocket must leave
+                // the deleted server too, or chat keeps its stale socket.
+                ProfileSwitchCoordinator.switchConnectionProfile(AuthManager.DEFAULT_PROFILE_ID)
+            } else {
+                ApiClient.rebuild()
+            }
+            loadSettings()
         }
-        viewModelScope.launch(ioDispatcher) { loadSettings() }
-        ApiClient.rebuild()
     }
 
     // ── Profile add/edit dialog ──────────────────────────────────────────

app/src/test/java/com/m57/hermescontrol/data/local/AuthManagerTest.kt

@@ -141,6 +141,32 @@ class AuthManagerTest {
         assertEquals(9090, AuthManager.getPort())
     }
 
+    @Test
+    fun testSetSelectedProfileId_refreshesBaseUrlFlow() {
+        AuthManager.ensureDefaultProfile()
+        AuthManager.setBaseUrl("http://10.0.0.1:9119/")
+        AuthManager.saveConnectionProfiles(
+            listOf(
+                ConnectionProfile(
+                    id = AuthManager.DEFAULT_PROFILE_ID,
+                    name = "Default",
+                    baseUrl = "http://10.0.0.1:9119/",
+                ),
+                ConnectionProfile(
+                    id = "prof-2",
+                    name = "Home",
+                    baseUrl = "http://10.0.0.2:9220/",
+                ),
+            ),
+        )
+
+        AuthManager.setSelectedProfileId("prof-2")
+
+        // contextFlow consumers must see the NEW server's URL after a
+        // connection-profile switch, not the previous one (split-brain fix).
+        assertEquals("http://10.0.0.2:9220/", AuthManager.baseUrlFlow.value)
+    }
+
     @Test
     fun testGetAndSetAutoReconnect() {
         AuthManager.setAutoReconnect(false)

app/src/test/java/com/m57/hermescontrol/data/session/ProfileSwitchCoordinatorTest.kt

@@ -113,5 +113,48 @@ class ProfileSwitchCoordinatorTest {
             verify(exactly = 0) { HermesWsClient.connect() }
         }
 
+    @Test
+    fun `connection switch re-homes selection retrofit and socket in order`() =
+        runTest {
+            every { AuthManager.setSelectedProfileId(any()) } returns Unit
+            every { ApiClient.rebuild() } returns Unit
+            coEvery { AuthManager.syncCookieStoreForProfile(any()) } returns Unit
+
+            ProfileSwitchCoordinator.switchConnectionProfile("prof-2")
+
+            // Load-bearing order: selection persists FIRST (token cache +
+            // cookie scope follow), Retrofit re-points, the cookie store swap
+            // is AWAITED (a racing dial mints the ticket with the previous
+            // server's cookie → 401 → dead socket), then the socket re-dials
+            // — so chat's wipe (via the broadcast) lands before the new
+            // gateway's gateway.ready auto-creates the fresh session.
+            coVerify(ordering = Ordering.SEQUENCE) {
+                AuthManager.setSelectedProfileId("prof-2")
+                ApiClient.rebuild()
+                AuthManager.syncCookieStoreForProfile("prof-2")
+                HermesWsClient.disconnect()
+                HermesWsClient.connect()
+            }
+        }
+
+    @Test
+    fun `connection switch broadcasts so chat wipes before the re-dial`() =
+        runTest {
+            every { AuthManager.setSelectedProfileId(any()) } returns Unit
+            every { ApiClient.rebuild() } returns Unit
+            coEvery { AuthManager.syncCookieStoreForProfile(any()) } returns Unit
+            // Subscribe BEFORE the switch — exactly how ChatViewModel does it.
+            val received = Channel<String>(Channel.UNLIMITED)
+            backgroundScope.launch {
+                ProfileSwitchCoordinator.connectionSwitched.collect { received.send(it) }
+            }
+            runCurrent()
+
+            ProfileSwitchCoordinator.switchConnectionProfile("prof-2")
+            runCurrent()
+
+            assertEquals("prof-2", received.tryReceive().getOrNull())
+        }
+
     private fun <T> errorResponse(code: Int): Response<T> = Response.error(code, "{}".toResponseBody(null))
 }

app/src/test/java/com/m57/hermescontrol/ui/chat/ChatUpdateCommandTest.kt

@@ -106,6 +106,7 @@ class ChatUpdateCommandTest {
         // collectors park harmlessly.
         mockkObject(ProfileSwitchCoordinator)
         every { ProfileSwitchCoordinator.switched } returns MutableSharedFlow<String>()
+        every { ProfileSwitchCoordinator.connectionSwitched } returns MutableSharedFlow<String>()
 
         every { HermesWsClient.send(any(), any(), any()) } answers {
             reqCount++

app/src/test/java/com/m57/hermescontrol/ui/chat/ChatViewModelTest.kt

@@ -126,6 +126,7 @@ class ChatViewModelTest {
         every { AuthManager.getSelectedProfileId() } returns null
         mockkObject(ProfileSwitchCoordinator)
         every { ProfileSwitchCoordinator.switched } returns mockSwitchFlow
+        every { ProfileSwitchCoordinator.connectionSwitched } returns MutableSharedFlow<String>()
         every { AuthManager.isTypingEffectEnabled() } returns true
         every { AuthManager.getTypingEffectDelayMs() } returns 30
         every { AuthManager.isAutoReconnect() } returns false

app/src/test/java/com/m57/hermescontrol/ui/chat/SlashCommandDispatchRpcTest.kt

@@ -84,6 +84,7 @@ class SlashCommandDispatchRpcTest {
         // pattern) so the collectors park harmlessly.
         mockkObject(ProfileSwitchCoordinator)
         every { ProfileSwitchCoordinator.switched } returns MutableSharedFlow<String>()
+        every { ProfileSwitchCoordinator.connectionSwitched } returns MutableSharedFlow<String>()
 
         app = mockk(relaxed = true)
         fakeRepo = FakeChatPersistenceRepository()

app/src/test/java/com/m57/hermescontrol/ui/settings/SettingsViewModelTest.kt

@@ -3,8 +3,11 @@ package com.m57.hermescontrol.ui.settings
 import com.m57.hermescontrol.data.config.ConnectionProfile
 import com.m57.hermescontrol.data.local.AuthManager
 import com.m57.hermescontrol.data.remote.ApiClient
+import com.m57.hermescontrol.data.session.ProfileSwitchCoordinator
 import com.m57.hermescontrol.theme.ThemePreference
 import com.m57.hermescontrol.theme.ThemePreset
+import io.mockk.coEvery
+import io.mockk.coVerify
 import io.mockk.every
 import io.mockk.mockkObject
 import io.mockk.unmockkAll
@@ -84,7 +87,15 @@ class SettingsViewModelTest {
         every { AuthManager.getProfileToken(any()) } returns null
         every { AuthManager.ensureDefaultProfile() } returns Unit
 
-        // Ensure ApiClient.rebuild() is stubbed (used by selectProfile)
+        // selectProfile/deleteProfile route the switch through the coordinator
+        // (selection + Retrofit + WebSocket re-dial). Mirror the selection
+        // side-effect like the real coordinator's setSelectedProfileId does,
+        // so loadSettings() observes the new selection.
+        mockkObject(ProfileSwitchCoordinator)
+        coEvery { ProfileSwitchCoordinator.switchConnectionProfile(any()) } answers {
+            storedSelectedProfileId = firstArg()
+            Unit
+        }
         every { ApiClient.rebuild() } returns Unit
     }
 
@@ -158,8 +169,7 @@ class SettingsViewModelTest {
         viewModel.selectProfile("prof-2")
         testDispatcher.scheduler.advanceUntilIdle()
 
-        verify { AuthManager.setSelectedProfileId("prof-2") }
-        verify { ApiClient.rebuild() }
+        coVerify { ProfileSwitchCoordinator.switchConnectionProfile("prof-2") }
         assertEquals("prof-2", viewModel.uiState.value.selectedProfileId)
         assertEquals("Home", viewModel.uiState.value.renameProfileName)
     }
@@ -174,8 +184,7 @@ class SettingsViewModelTest {
         viewModel.selectProfile(AuthManager.DEFAULT_PROFILE_ID)
         testDispatcher.scheduler.advanceUntilIdle()
 
-        verify { AuthManager.setSelectedProfileId(AuthManager.DEFAULT_PROFILE_ID) }
-        verify { ApiClient.rebuild() }
+        coVerify { ProfileSwitchCoordinator.switchConnectionProfile(AuthManager.DEFAULT_PROFILE_ID) }
         assertEquals(AuthManager.DEFAULT_PROFILE_ID, viewModel.uiState.value.selectedProfileId)
     }
 
@@ -187,11 +196,13 @@ class SettingsViewModelTest {
         val viewModel = createViewModel()
 
         viewModel.deleteProfile("prof-1")
+        testDispatcher.scheduler.advanceUntilIdle()
 
         verify { AuthManager.saveConnectionProfiles(any()) }
         verify { AuthManager.setProfileToken("prof-1", null) }
-        verify { AuthManager.setSelectedProfileId(AuthManager.DEFAULT_PROFILE_ID) }
-        verify { ApiClient.rebuild() }
+        // The deleted profile was selected — the fallback switch re-homes
+        // everything (selection + Retrofit + WebSocket) to default.
+        coVerify { ProfileSwitchCoordinator.switchConnectionProfile(AuthManager.DEFAULT_PROFILE_ID) }
     }
 
     @Test
@@ -202,11 +213,13 @@ class SettingsViewModelTest {
         val viewModel = createViewModel()
 
         viewModel.deleteProfile("prof-2")
+        testDispatcher.scheduler.advanceUntilIdle()
 
         verify { AuthManager.saveConnectionProfiles(any()) }
         verify { AuthManager.setProfileToken("prof-2", null) }
         // Selected profile (prof-1) was NOT deleted — should NOT change selection
         verify(exactly = 0) { AuthManager.setSelectedProfileId(any()) }
+        coVerify(exactly = 0) { ProfileSwitchCoordinator.switchConnectionProfile(any()) }
         verify { ApiClient.rebuild() }
     }