address review: probe the active source so media falls back too

An existing token-auth source with an already-synced library would fail playback before
any API call ran: stream and cover-art URLs are built by uri() and fetched by
ExoPlayer/Coil, outside stream(). Probe the active source once when it uses token auth so
the 41 flips and persists before any URL is built.

Also base the retry on the flag the request actually used (concurrent requests no longer
lose their retry), report the fallback from ping() so Add Source flips the toggle instead
of reporting success and saving token auth on, and make the callback non-null.

app/src/main/kotlin/com/subtracks/data/repo/SourceRepository.kt

@@ -31,6 +31,7 @@ class SourceRepository(
 
     @Volatile
     private var active: SubsonicMusicSource? = null
+    private var probedTokenAuthId: Long? = null
 
     init {
         scope.launch {
@@ -38,8 +39,16 @@ class SourceRepository(
                 db.sourcesDao().activeSubsonicConfig(),
                 prefs.maxBitrate,
                 prefs.streamFormat,
-            ) { config, maxBitrate, streamFormat -> config?.toMusicSource(maxBitrate, streamFormat) }
-                .collect { active = it }
+            ) { config, maxBitrate, streamFormat -> Triple(config, maxBitrate, streamFormat) }
+                .collect { (config, maxBitrate, streamFormat) ->
+                    active = config?.toMusicSource(maxBitrate, streamFormat)
+                    config
+                        ?.takeIf { it.useTokenAuth && it.id != probedTokenAuthId }
+                        ?.let { source ->
+                            probedTokenAuthId = source.id
+                            scope.launch { runCatching { source.toClient().check("ping") } }
+                        }
+                }
         }
     }
 
@@ -111,9 +120,12 @@ class SourceRepository(
         username: String,
         password: String,
         useTokenAuth: Boolean,
-    ): Result<Unit> =
+    ): Result<Boolean> =
         withContext(Dispatchers.IO) {
-            runCatching { client(address, username, password, useTokenAuth).check("ping") }
+            var fellBack = false
+            runCatching {
+                client(address, username, password, useTokenAuth) { fellBack = true }.check("ping")
+            }.map { fellBack }
         }
 
     suspend fun activeMusicSource(): MusicSource? {
@@ -121,20 +133,22 @@ class SourceRepository(
         return config.toMusicSource(prefs.maxBitrate.first(), prefs.streamFormat.first())
     }
 
+    private fun SubsonicConfig.toClient(): SubsonicClient =
+        client(
+            address = address,
+            username = username,
+            password = password,
+            useTokenAuth = useTokenAuth,
+            onTokenAuthUnsupported = { disableTokenAuth(id) },
+        )
+
     private fun SubsonicConfig.toMusicSource(
         maxBitrate: Int,
         streamFormat: String?,
     ): SubsonicMusicSource =
         SubsonicMusicSource(
             id = id,
-            client =
-                client(
-                    address = address,
-                    username = username,
-                    password = password,
-                    useTokenAuth = useTokenAuth,
-                    onTokenAuthUnsupported = { disableTokenAuth(id) },
-                ),
+            client = toClient(),
             maxBitrate = maxBitrate,
             streamFormat = streamFormat,
         )
@@ -151,7 +165,7 @@ class SourceRepository(
         username: String,
         password: String,
         useTokenAuth: Boolean,
-        onTokenAuthUnsupported: (() -> Unit)? = null,
+        onTokenAuthUnsupported: () -> Unit = {},
     ) = SubsonicClient(
         baseUrl = normalizeAddress(address).toHttpUrl(),
         username = username,

app/src/main/kotlin/com/subtracks/data/source/subsonic/SubsonicClient.kt

@@ -18,7 +18,7 @@ class SubsonicClient(
     useTokenAuth: Boolean,
     private val http: OkHttpClient,
     private val userAgent: String = "subtracks/android",
-    private val onTokenAuthUnsupported: (() -> Unit)? = null,
+    private val onTokenAuthUnsupported: () -> Unit = {},
 ) {
     @Volatile
     private var useTokenAuth: Boolean = useTokenAuth
@@ -53,14 +53,16 @@ class SubsonicClient(
         method: String,
         params: Map<String, String> = emptyMap(),
         body: (InputStream) -> T,
-    ): T =
-        try {
+    ): T {
+        val usedTokenAuth = useTokenAuth
+        return try {
             execute(method, params, body)
         } catch (failure: SubsonicException) {
-            if (failure.code != TOKEN_AUTH_UNSUPPORTED || !useTokenAuth) throw failure
+            if (failure.code != TOKEN_AUTH_UNSUPPORTED || !usedTokenAuth) throw failure
             disableTokenAuth()
             execute(method, params, body)
         }
+    }
 
     private fun <T> execute(
         method: String,
@@ -85,7 +87,7 @@ class SubsonicClient(
     private fun disableTokenAuth() {
         if (!useTokenAuth) return
         useTokenAuth = false
-        onTokenAuthUnsupported?.invoke()
+        onTokenAuthUnsupported()
     }
 
     companion object {

app/src/main/kotlin/com/subtracks/ui/settings/AddSourceViewModel.kt

@@ -42,10 +42,16 @@ class AddSourceViewModel(
         val current = _state.value
         viewModelScope.launch {
             val result = sourceRepository.ping(current.address, current.username, current.password, current.useTokenAuth)
-            _state.update {
-                it.copy(
+            _state.update { state ->
+                val fellBack = result.getOrDefault(false)
+                state.copy(
                     busy = false,
-                    message = result.fold({ "Connection OK" }, { error -> "Failed: ${error.message}" }),
+                    useTokenAuth = if (fellBack) false else state.useTokenAuth,
+                    message =
+                        result.fold(
+                            { if (fellBack) "Server does not support token auth; using the password instead" else "Connection OK" },
+                            { error -> "Failed: ${error.message}" },
+                        ),
                     isError = result.isFailure,
                 )
             }