fix(aap): Keep device settings visible when BLE scan goes stale

app/src/main/java/eu/darken/capod/monitor/core/DeviceMonitor.kt

@@ -1,5 +1,6 @@
 package eu.darken.capod.monitor.core
 
+import eu.darken.capod.common.bluetooth.BluetoothAddress
 import eu.darken.capod.common.coroutine.AppScope
 import eu.darken.capod.common.debug.logging.Logging.Priority.VERBOSE
 import eu.darken.capod.common.debug.logging.log
@@ -10,6 +11,8 @@ import eu.darken.capod.monitor.core.ble.BlePodMonitor
 import eu.darken.capod.monitor.core.cache.DeviceStateCache
 import eu.darken.capod.monitor.core.cache.toCachedState
 import eu.darken.capod.pods.core.apple.aap.AapConnectionManager
+import eu.darken.capod.pods.core.apple.aap.AapPodState
+import eu.darken.capod.profiles.core.DeviceProfile
 import eu.darken.capod.profiles.core.DeviceProfilesRepo
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.flow.Flow
@@ -48,24 +51,31 @@ class DeviceMonitor @Inject constructor(
     ) { pods, aapStates, cachedStates, profiles ->
         // Live devices — BLE + AAP + cached fallback for missing fields
         val liveDevices = pods.map { pod ->
-            val bondedAddress = pod.meta.profile?.address
             val profile = pod.meta.profile
             PodDevice(
                 profileId = profile?.id,
                 label = profile?.label,
                 ble = pod,
-                aap = bondedAddress?.let { aapStates[it] },
+                aap = aapStates.forProfile(profile),
                 cached = profile?.id?.let { cachedStates[it] },
             )
         }
 
-        // Cached-only devices — profiles with cache but no live BLE
+        // Cached-only devices — profiles with cache but no live BLE.
+        // AAP may still be connected even when BLE scan is stale in a crowded RF environment,
+        // so re-attach AAP state via the same helper — see #483.
         val liveProfileIds = liveDevices.mapNotNull { it.profileId }.toSet()
         val cachedOnlyDevices = profiles
             .filter { it.id !in liveProfileIds }
             .mapNotNull { profile ->
-                cachedStates[profile.id]?.let {
+                cachedStates[profile.id]?.let { cached ->
-                    PodDevice(profileId = profile.id, label = profile.label, ble = null, aap = null, cached = it)
+                    PodDevice(
+                        profileId = profile.id,
+                        label = profile.label,
+                        ble = null,
+                        aap = aapStates.forProfile(profile),
+                        cached = cached,
+                    )
                 }
             }
 
@@ -105,6 +115,14 @@ class DeviceMonitor @Inject constructor(
         return null
     }
 
+    /**
+     * Single source of truth for "find the AAP state that belongs to this profile".
+     * AAP is keyed by the bonded BR/EDR address, which lives on [DeviceProfile.address].
+     * Used by both the live and cached-only branches of [devices] so they cannot drift apart.
+     */
+    private fun Map<BluetoothAddress, AapPodState>.forProfile(profile: DeviceProfile?): AapPodState? =
+        profile?.address?.let { this[it] }
+
     companion object {
         private val TAG = logTag("DeviceMonitor")
     }

app/src/test/java/eu/darken/capod/monitor/core/DeviceMonitorTest.kt

@@ -0,0 +1,184 @@
+package eu.darken.capod.monitor.core
+
+import eu.darken.capod.common.bluetooth.BluetoothAddress
+import eu.darken.capod.monitor.core.aap.AapLifecycleManager
+import eu.darken.capod.monitor.core.ble.BlePodMonitor
+import eu.darken.capod.monitor.core.cache.CachedDeviceState
+import eu.darken.capod.monitor.core.cache.DeviceStateCache
+import eu.darken.capod.pods.core.apple.PodModel
+import eu.darken.capod.pods.core.apple.aap.AapConnectionManager
+import eu.darken.capod.pods.core.apple.aap.AapPodState
+import eu.darken.capod.pods.core.apple.ble.BlePodSnapshot
+import eu.darken.capod.profiles.core.AppleDeviceProfile
+import eu.darken.capod.profiles.core.DeviceProfile
+import eu.darken.capod.profiles.core.DeviceProfilesRepo
+import io.kotest.matchers.shouldBe
+import io.mockk.every
+import io.mockk.mockk
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.test.UnconfinedTestDispatcher
+import kotlinx.coroutines.test.runTest
+import org.junit.jupiter.api.Test
+import testhelpers.BaseTest
+import java.time.Instant
+
+@OptIn(ExperimentalCoroutinesApi::class)
+class DeviceMonitorTest : BaseTest() {
+
+    private val testDispatcher = UnconfinedTestDispatcher()
+
+    private val testAddress: BluetoothAddress = "AA:BB:CC:DD:EE:FF"
+    private val testProfile = AppleDeviceProfile(
+        label = "Test AirPods",
+        model = PodModel.AIRPODS_PRO2_USBC,
+        address = testAddress,
+    )
+    private val noAddressProfile = AppleDeviceProfile(
+        label = "No Address",
+        model = PodModel.AIRPODS_PRO2_USBC,
+        address = null,
+    )
+
+    private val testCachedState = CachedDeviceState(
+        profileId = testProfile.id,
+        model = PodModel.AIRPODS_PRO2_USBC,
+        address = testAddress,
+        lastSeenAt = Instant.parse("2026-04-05T17:52:09.182Z"),
+    )
+
+    private val testAapState = AapPodState(
+        connectionState = AapPodState.ConnectionState.READY,
+        lastMessageAt = Instant.parse("2026-04-05T17:52:47.881Z"),
+    )
+
+    private fun mockBlePodWithProfile(profile: DeviceProfile): BlePodSnapshot {
+        val bleMeta = object : BlePodSnapshot.Meta {
+            override val profile: DeviceProfile? = profile
+        }
+        return mockk(relaxed = true) {
+            every { meta } returns bleMeta
+        }
+    }
+
+    private fun createMonitor(
+        ble: List<BlePodSnapshot> = emptyList(),
+        aap: Map<BluetoothAddress, AapPodState> = emptyMap(),
+        cache: Map<String, CachedDeviceState> = emptyMap(),
+        profiles: List<DeviceProfile> = emptyList(),
+        scope: CoroutineScope,
+    ): DeviceMonitor {
+        val blePodMonitor: BlePodMonitor = mockk {
+            every { devices } returns MutableStateFlow(ble)
+        }
+        val aapManager: AapConnectionManager = mockk {
+            every { allStates } returns MutableStateFlow(aap)
+        }
+        val deviceStateCache: DeviceStateCache = mockk(relaxed = true) {
+            every { cachedStates } returns MutableStateFlow(cache)
+        }
+        val profilesRepo: DeviceProfilesRepo = mockk {
+            every { this@mockk.profiles } returns MutableStateFlow(profiles)
+        }
+        val aapLifecycleManager: AapLifecycleManager = mockk(relaxed = true)
+
+        return DeviceMonitor(
+            appScope = scope,
+            blePodMonitor = blePodMonitor,
+            aapManager = aapManager,
+            deviceStateCache = deviceStateCache,
+            profilesRepo = profilesRepo,
+            aapLifecycleManager = aapLifecycleManager,
+        )
+    }
+
+    @Test
+    fun `BLE present and AAP present - live device has AAP attached`() = runTest(testDispatcher) {
+        val monitor = createMonitor(
+            ble = listOf(mockBlePodWithProfile(testProfile)),
+            aap = mapOf(testAddress to testAapState),
+            cache = mapOf(testProfile.id to testCachedState),
+            profiles = listOf(testProfile),
+            scope = backgroundScope,
+        )
+
+        val devices = monitor.devices.first()
+
+        devices.size shouldBe 1
+        val device = devices.single()
+        device.profileId shouldBe testProfile.id
+        device.isAapConnected shouldBe true
+        device.isAapReady shouldBe true
+    }
+
+    /**
+     * Regression test for https://github.com/d4rken-org/capod/issues/483 — settings disappeared
+     * when BLE went stale even though the AAP socket was still healthy.
+     */
+    @Test
+    fun `BLE stale and cache present and AAP present - cached-only device still has AAP attached`() =
+        runTest(testDispatcher) {
+            val monitor = createMonitor(
+                ble = emptyList(), // BLE evicted
+                aap = mapOf(testAddress to testAapState),
+                cache = mapOf(testProfile.id to testCachedState),
+                profiles = listOf(testProfile),
+                scope = backgroundScope,
+            )
+
+            val devices = monitor.devices.first()
+
+            devices.size shouldBe 1
+            val device = devices.single()
+            device.profileId shouldBe testProfile.id
+            device.address shouldBe testAddress
+            device.isAapConnected shouldBe true
+            device.isAapReady shouldBe true
+        }
+
+    @Test
+    fun `BLE stale and cache present and AAP absent - cached-only device has AAP null`() =
+        runTest(testDispatcher) {
+            val monitor = createMonitor(
+                ble = emptyList(),
+                aap = emptyMap(), // AAP also gone
+                cache = mapOf(testProfile.id to testCachedState),
+                profiles = listOf(testProfile),
+                scope = backgroundScope,
+            )
+
+            val devices = monitor.devices.first()
+
+            devices.size shouldBe 1
+            val device = devices.single()
+            device.profileId shouldBe testProfile.id
+            device.isAapConnected shouldBe false
+        }
+
+    @Test
+    fun `profile without address never binds to AAP entries`() = runTest(testDispatcher) {
+        val cachedForNoAddress = CachedDeviceState(
+            profileId = noAddressProfile.id,
+            model = PodModel.AIRPODS_PRO2_USBC,
+            address = null,
+            lastSeenAt = Instant.parse("2026-04-05T17:52:09.182Z"),
+        )
+        val monitor = createMonitor(
+            ble = emptyList(),
+            // AAP map contains an entry, but it's for a different address.
+            aap = mapOf(testAddress to testAapState),
+            cache = mapOf(noAddressProfile.id to cachedForNoAddress),
+            profiles = listOf(noAddressProfile),
+            scope = backgroundScope,
+        )
+
+        val devices = monitor.devices.first()
+
+        devices.size shouldBe 1
+        val device = devices.single()
+        device.profileId shouldBe noAddressProfile.id
+        device.isAapConnected shouldBe false
+    }
+}