fix(aap): Fix flush ANC debounce, HANDSHAKING→READY regression, and flush ordering

Track lastAncSentAt separately so non-ANC commands during flush don't break the ANC echo debounce window. Prioritize ANC for post-flush verification.

Move HANDSHAKING→READY transition to top of processMessage so decoded battery, stem press, and device info messages also trigger it.

Sort flush: AllowOffOption before AncMode before others, preventing device rejection when enabling OFF mode.

app/src/main/java/eu/darken/capod/pods/core/apple/aap/AapConnection.kt

@@ -38,8 +38,7 @@ internal class AapConnection(
     private val device: BluetoothDevice,
     private val profile: AapDeviceProfile,
     private val socketFactory: L2capSocketFactory,
-    private val timeSource: TimeSource,
-    private val psm: Int = 0x1001,
+    timeSource: TimeSource,
 ) {
 
     private val engine = AapSessionEngine(profile, timeSource)
@@ -65,7 +64,7 @@ internal class AapConnection(
         engine.start(scope)
 
         try {
-            val sock = socketFactory.createSocket(device, psm)
+            val sock = socketFactory.createSocket(device, PSM)
             sock.connect()
             socket = sock
             log(TAG, INFO) { "Connected to ${device.address}" }
@@ -168,6 +167,7 @@ internal class AapConnection(
     }
 
     companion object {
+        private const val PSM = 0x1001
         private val TAG = logTag("AAP", "Connection")
     }
 }

app/src/main/java/eu/darken/capod/pods/core/apple/aap/AapSessionEngine.kt

@@ -55,6 +55,8 @@ internal class AapSessionEngine(
     private var ancDebounceJob: Job? = null
     private var lastSentCommand: AapCommand? = null
     private var lastSentAt: Long = 0L
+    /** Separate tracking for ANC sends — not overwritten by non-ANC commands during flush. */
+    private var lastAncSentAt: Long = 0L
     private var handshakeResponseReceived: Boolean = false
 
     /** Stored reference to the socket write callback — set on each [send] / flush call. */
@@ -82,6 +84,7 @@ internal class AapSessionEngine(
         scope = null
         lastSentCommand = null
         lastSentAt = 0L
+        lastAncSentAt = 0L
         activeSendRaw = null
         handshakeResponseReceived = false
         _state.value = AapPodState(connectionState = AapPodState.ConnectionState.DISCONNECTED)
@@ -148,7 +151,9 @@ internal class AapSessionEngine(
     private suspend fun wrappedSend(sendRaw: suspend (AapCommand) -> Unit, command: AapCommand) {
         sendRaw(command)
         lastSentCommand = command
-        lastSentAt = timeSource.currentTimeMillis()
+        val now = timeSource.currentTimeMillis()
+        lastSentAt = now
+        if (command is AapCommand.SetAncMode) lastAncSentAt = now
     }
 
     private fun onVerificationOutcome(outcome: AapSettingsCoordinator.VerificationOutcome) {
@@ -173,6 +178,16 @@ internal class AapSessionEngine(
         val hex = message.raw.joinToString(" ") { "%02X".format(it) }
         log(TAG, VERBOSE) { "MSG cmd=0x${"%04X".format(message.commandType)} len=${message.raw.size} raw=$hex" }
 
+        // HANDSHAKING → READY: first non-settings-echo message means the device is talking.
+        // Must happen before any early returns so decoded messages (battery, stem, etc.) also trigger it.
+        if (!handshakeResponseReceived && message.commandType != 0x0009
+            && _state.value.connectionState == AapPodState.ConnectionState.HANDSHAKING
+        ) {
+            handshakeResponseReceived = true
+            _state.value = _state.value.copy(connectionState = AapPodState.ConnectionState.READY)
+            log(TAG) { "Connection READY" }
+        }
+
         // Issue #173 diagnostic dump
         if (message.commandType == 0x001D) {
             val segments = describeDeviceInfoSegments(message.payload)
@@ -241,8 +256,7 @@ internal class AapSessionEngine(
             // ANC debounce
             if (value is AapSetting.AncMode) {
                 val isFirstAncMode = _state.value.setting<AapSetting.AncMode>() == null
-                val recentAncSend =
-                    lastSentCommand is AapCommand.SetAncMode && (timeSource.currentTimeMillis() - lastSentAt) <= 3000L
+                val recentAncSend = lastAncSentAt > 0L && (timeSource.currentTimeMillis() - lastAncSentAt) <= 3000L
                 if (isFirstAncMode || recentAncSend) {
                     ancDebounceJob?.cancel()
                     _state.value = _state.value.withSetting(key, value).copy(lastMessageAt = timeSource.now())
@@ -309,7 +323,10 @@ internal class AapSessionEngine(
                                 break
                             }
                         }
-                        commands.lastOrNull()?.let {
+                        // Verify ANC mode if it was in the batch (most important for divergence detection).
+                        // Fall back to verifying the last command if no ANC was flushed.
+                        val toVerify = commands.firstOrNull { it is AapCommand.SetAncMode } ?: commands.lastOrNull()
+                        toVerify?.let {
                             coordinator.startVerification(
                                 it,
                                 this,
@@ -322,22 +339,9 @@ internal class AapSessionEngine(
                 }
             }
 
-            // HANDSHAKING → READY transition
-            if (!handshakeResponseReceived && _state.value.connectionState == AapPodState.ConnectionState.HANDSHAKING) {
-                handshakeResponseReceived = true
-                _state.value = _state.value.copy(connectionState = AapPodState.ConnectionState.READY)
-                log(TAG) { "Connection READY" }
-            }
             return
         }
 
-        // Track handshake response for non-setting messages too
-        if (!handshakeResponseReceived && message.commandType != 0x0009 && _state.value.connectionState == AapPodState.ConnectionState.HANDSHAKING) {
-            handshakeResponseReceived = true
-            _state.value = _state.value.copy(connectionState = AapPodState.ConnectionState.READY)
-            log(TAG) { "Connection READY" }
-        }
-
         val payloadHex = message.payload.joinToString(" ") { "%02X".format(it) }
         val sinceSend = if (lastSentAt == 0L) -1L else timeSource.currentTimeMillis() - lastSentAt
         val lastSend = lastSentCommand?.let { it::class.simpleName } ?: "none"

app/src/main/java/eu/darken/capod/pods/core/apple/aap/AapSettingsCoordinator.kt

@@ -73,7 +73,16 @@ internal class AapSettingsCoordinator(
             commands = pendingCommands.values.toList()
             pendingCommands.clear()
         }
-        val sorted = commands.sortedBy { if (it is AapCommand.SetAncMode) 0 else 1 }
+        // Dependency-aware ordering:
+        // AllowOffOption must precede AncMode (device rejects OFF without it)
+        // AncMode must precede mode-dependent settings (e.g. AdaptiveAudioNoise)
+        val sorted = commands.sortedBy {
+            when (it) {
+                is AapCommand.SetAllowOffOption -> 0
+                is AapCommand.SetAncMode -> 1
+                else -> 2
+            }
+        }
         return sorted to snapshot()
     }