feat(profiles): ProfileContext single source of truth + per-server token fallback (phase 1) (#821)

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

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

@@ -25,8 +25,11 @@ import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.async
 import kotlinx.coroutines.cancel
 import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.SharingStarted
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.flow.combine
+import kotlinx.coroutines.flow.stateIn
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.runBlocking
 
@@ -77,6 +80,30 @@ object AuthManager {
     private val _selectedProfileFlow = MutableStateFlow<String?>(null)
     val selectedProfileFlow: StateFlow<String?> = _selectedProfileFlow.asStateFlow()
 
+    private val _baseUrlFlow = MutableStateFlow("")
+    val baseUrlFlow: StateFlow<String> = _baseUrlFlow.asStateFlow()
+
+    private val contextScope = CoroutineScope(Dispatchers.Default)
+
+    /**
+     * The single source of truth for connection state: server URL + token +
+     * selected profile. Emits on login, logout, profile switch, or URL change,
+     * so reactive consumers (screens, switch coordinator) re-home off ONE
+     * flow instead of tracking the pieces separately.
+     */
+    val contextFlow: StateFlow<ProfileContext?> =
+        combine(tokenFlow, baseUrlFlow, selectedProfileFlow) { token, baseUrl, profileId ->
+            if (baseUrl.isBlank()) {
+                null
+            } else {
+                ProfileContext(baseUrl = baseUrl, token = token, profileId = profileId)
+            }
+        }.stateIn(
+            scope = contextScope,
+            started = SharingStarted.Eagerly,
+            initialValue = null,
+        )
+
     /**
      * Initialise the encrypted preferences.
      * Call this once from Application.onCreate() or MainActivity.onCreate().
@@ -103,6 +130,7 @@ object AuthManager {
             val store = ServerStore(dataStore, scope)
             _serverStore = store
             _selectedProfileFlow.value = store.getLatestState().selectedProfileId
+            _baseUrlFlow.value = store.getLatestState().resolvedBaseUrl
 
             if (prefsDeferred == null) {
                 prefsDeferred =
@@ -394,8 +422,7 @@ object AuthManager {
         if (tokenInitialized) return cachedToken
         synchronized(this) {
             if (tokenInitialized) return cachedToken
-            val selectedId = getSelectedProfileId()
-            val token = if (selectedId != null) getProfileToken(selectedId) else null
+            val token = resolveConnectionToken(getSelectedProfileId(), ::getProfileToken)
             cachedToken = token
             tokenInitialized = true
             return token
@@ -403,12 +430,24 @@ object AuthManager {
     }
 
     private fun getTokenInternal(p: SharedPreferences): String? {
-        val selectedId = serverStore.getLatestState().selectedProfileId?.takeIf { it.isNotBlank() }
-        return if (selectedId != null) {
-            p.getString("token_$selectedId", null)
-        } else {
-            null
-        }
+        val selectedId = serverStore.getLatestState().selectedProfileId
+        return resolveConnectionToken(selectedId) { id -> p.getString("token_$id", null) }
+    }
+
+    /**
+     * Per-server token semantics: a profile that has no token of its own
+     * inherits the connection (default) token — same dashboard = same auth.
+     * This is what makes profile switching never require a re-login, and it
+     * is restart-safe (the fallback applies on every resolution, not just
+     * at switch time). Profiles with their own token (a different server
+     * connection) keep it untouched.
+     */
+    internal fun resolveConnectionToken(
+        selectedId: String?,
+        tokenFor: (String) -> String?,
+    ): String? {
+        val id = selectedId?.takeIf { it.isNotBlank() } ?: DEFAULT_PROFILE_ID
+        return tokenFor(id) ?: tokenFor(DEFAULT_PROFILE_ID)
     }
 
     fun setToken(token: String?) {
@@ -444,6 +483,7 @@ object AuthManager {
                     CleartextPolicy.ALLOW_WITH_WARNING,
                 ).baseUrl
                 .toString()
+        _baseUrlFlow.value = normalized
         val selectedId =
             getSelectedProfileId() ?: run {
                 ensureDefaultSelected()

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

@@ -0,0 +1,19 @@
+package com.m57.hermescontrol.data.local
+
+/**
+ * The app's single source of truth for "where am I + who am I".
+ *
+ * Emitted by [AuthManager.contextFlow] whenever the connected server
+ * ([baseUrl]), its [token], or the selected [profileId] changes — so
+ * screens and the switch coordinator can re-home reactively instead of
+ * each layer tracking its own slice of connection state.
+ */
+data class ProfileContext(
+    val baseUrl: String,
+    val token: String?,
+    val profileId: String?,
+) {
+    /** True when a non-default profile is explicitly selected. */
+    val isProfileScoped: Boolean
+        get() = profileId != null && profileId != AuthManager.DEFAULT_PROFILE_ID
+}

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

@@ -199,12 +199,13 @@ class AuthManagerTest {
     }
 
     @Test
-    fun testGetToken_returnsNullWhenProfileHasNoToken() {
+    fun testGetToken_profileWithoutToken_fallsBackToDefault() {
         val profile1 = ConnectionProfile(id = "prof-1", name = "Profile 1", baseUrl = "http://127.0.0.1:9119/")
         AuthManager.saveConnectionProfiles(listOf(profile1))
         every { mockPrefs.getString("token_prof-1", null) } returns null
+        every { mockPrefs.getString("token_${AuthManager.DEFAULT_PROFILE_ID}", null) } returns "connection-token"
         AuthManager.setSelectedProfileId("prof-1")
-        assertNull(AuthManager.getToken())
+        assertEquals("connection-token", AuthManager.getToken())
     }
 
     @Test
@@ -325,40 +326,50 @@ class AuthManagerTest {
     }
 
     @Test
-    fun testGetToken_profileWithNoTokenReturnsNull() {
+    fun testGetToken_profileWithoutToken_fallsBackToDefaultToken() {
         val profileA = ConnectionProfile(id = "prof-a", name = "Profile A", baseUrl = "http://127.0.0.1:9119/")
         val profileB = ConnectionProfile(id = "prof-b", name = "Profile B", baseUrl = "http://127.0.0.1:9119/")
         AuthManager.saveConnectionProfiles(listOf(profileA, profileB))
 
-        // Profile A is selected but has no token → null (no global fallback)
+        // The default profile carries the connection token.
+        every { mockPrefs.getString("token_${AuthManager.DEFAULT_PROFILE_ID}", null) } returns "conn-token"
+
+        // Profile A is selected but has no token → inherits the connection token
         every { mockPrefs.getString("token_prof-a", null) } returns null
         AuthManager.setSelectedProfileId("prof-a")
-        assertNull(AuthManager.getToken())
+        assertEquals("conn-token", AuthManager.getToken())
 
-        // Switch to Profile B, which also has no token → still null
+        // Profile B also has no token → same fallback
         every { mockPrefs.getString("token_prof-b", null) } returns null
         AuthManager.setSelectedProfileId("prof-b")
+        assertEquals("conn-token", AuthManager.getToken())
+
+        // When even the default has no token → null
+        every { mockPrefs.getString("token_${AuthManager.DEFAULT_PROFILE_ID}", null) } returns null
+        AuthManager.setSelectedProfileId("prof-a")
         assertNull(AuthManager.getToken())
     }
 
     @Test
-    fun testGetToken_selectiveProfileTokens_someNull() {
+    fun testGetToken_selectiveProfileTokens_fallsBackWhenMissing() {
         val profileA = ConnectionProfile(id = "prof-a", name = "Profile A", baseUrl = "http://127.0.0.1:9119/")
         val profileB = ConnectionProfile(id = "prof-b", name = "Profile B", baseUrl = "http://127.0.0.1:9119/")
         val profileC = ConnectionProfile(id = "prof-c", name = "Profile C", baseUrl = "http://127.0.0.1:9119/")
         AuthManager.saveConnectionProfiles(listOf(profileA, profileB, profileC))
 
-        // Profile A has a token
+        every { mockPrefs.getString("token_${AuthManager.DEFAULT_PROFILE_ID}", null) } returns "conn-token"
+
+        // Profile A has a token → its own wins
         every { mockPrefs.getString("token_prof-a", null) } returns "token-a"
         AuthManager.setSelectedProfileId("prof-a")
         assertEquals("token-a", AuthManager.getToken())
 
-        // Profile B has no token → null
+        // Profile B has no token → inherits the connection (default) token
         every { mockPrefs.getString("token_prof-b", null) } returns null
         AuthManager.setSelectedProfileId("prof-b")
-        assertNull(AuthManager.getToken())
+        assertEquals("conn-token", AuthManager.getToken())
 
-        // Profile C has its own token too
+        // Profile C has its own token too → its own wins
         every { mockPrefs.getString("token_prof-c", null) } returns "token-c"
         AuthManager.setSelectedProfileId("prof-c")
         assertEquals("token-c", AuthManager.getToken())

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

@@ -0,0 +1,75 @@
+package com.m57.hermescontrol.data.local
+
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNull
+import org.junit.Test
+
+/**
+ * Tests for the per-server token resolution that makes profile switching
+ * restart-safe without a re-login.
+ *
+ * Rule: a profile without its own token inherits the connection (default)
+ * token — same dashboard = same auth.
+ */
+class AuthManagerTokenTest {
+    @Test
+    fun `selected profile with own token keeps it`() {
+        val token = AuthManager.resolveConnectionToken("meow") { id -> if (id == "meow") "tok-meow" else null }
+        assertEquals("tok-meow", token)
+    }
+
+    @Test
+    fun `selected profile without own token inherits default token`() {
+        val token =
+            AuthManager.resolveConnectionToken("meow") { id ->
+                if (id == AuthManager.DEFAULT_PROFILE_ID) "tok-conn" else null
+            }
+        assertEquals("tok-conn", token)
+    }
+
+    @Test
+    fun `default profile uses its own token`() {
+        val token =
+            AuthManager.resolveConnectionToken(AuthManager.DEFAULT_PROFILE_ID) { id ->
+                if (id == AuthManager.DEFAULT_PROFILE_ID) "tok-conn" else null
+            }
+        assertEquals("tok-conn", token)
+    }
+
+    @Test
+    fun `null selection falls back to default token`() {
+        val token =
+            AuthManager.resolveConnectionToken(null) { id ->
+                if (id == AuthManager.DEFAULT_PROFILE_ID) "tok-conn" else null
+            }
+        assertEquals("tok-conn", token)
+    }
+
+    @Test
+    fun `blank selection treated as default`() {
+        val token =
+            AuthManager.resolveConnectionToken("  ") { id ->
+                if (id == AuthManager.DEFAULT_PROFILE_ID) "tok-conn" else null
+            }
+        assertEquals("tok-conn", token)
+    }
+
+    @Test
+    fun `no tokens anywhere returns null`() {
+        assertNull(AuthManager.resolveConnectionToken("meow") { null })
+        assertNull(AuthManager.resolveConnectionToken(null) { null })
+    }
+
+    @Test
+    fun `own token beats default token when both exist`() {
+        val token =
+            AuthManager.resolveConnectionToken("meow") { id ->
+                when (id) {
+                    "meow" -> "tok-meow"
+                    AuthManager.DEFAULT_PROFILE_ID -> "tok-conn"
+                    else -> null
+                }
+            }
+        assertEquals("tok-meow", token)
+    }
+}