feat(aap): Surface Optimized Charge indicator and Pro 3 toggle

Adds a per-battery 'Optimized' chip on the overview card when pods report wire value 0x05 (CHARGING_OPTIMIZED), which was already decoded but collapsed into a plain 'Charging' in the UI. On AirPods Pro 3, also adds a user-facing toggle for the device-side Optimized Charge Limit (AAP setting 0x3B). - Decode setting 0x3B via decodeAppleBool so unknown values fall through instead of coercing to false - Bypass ear-detection queue for SetDynamicEndOfCharge so the toggle works while pods sit in the closed case - Expose per-slot ChargingState? on PodDevice; StatusChipRow renders 'Optimized' for CHARGING_OPTIMIZED, 'Charging' for CHARGING - New BatteryCard in device settings with experimental warning (pattern matches Sleep Detection) - Generic settingRejectedEvents flow alongside the existing offRejectedEvents so the toggle can show a dedicated snackbar on verification failure
2026-09-14 18:26:11 -04:00 · 2026-04-24 17:27:48 +02:00
parent 89e8b83be4
commit 59b3106c3b
21 changed files with 327 additions and 15 deletions
@@ -42,6 +42,7 @@ import eu.darken.capod.common.navigation.NavigationEventHandler
 import eu.darken.capod.common.settings.SettingsInfoBox
 import eu.darken.capod.common.settings.SettingsSection
 import eu.darken.capod.main.ui.devicesettings.cards.AapUnavailableCard
+import eu.darken.capod.main.ui.devicesettings.cards.BatteryCard
 import eu.darken.capod.main.ui.devicesettings.cards.ControlsCard
 import eu.darken.capod.main.ui.devicesettings.cards.DeviceInfoCard
 import eu.darken.capod.main.ui.devicesettings.cards.NoiseControlCard
@@ -84,6 +85,7 @@ fun DeviceSettingsScreenHost(
    var showListeningModeCycleDialog by rememberSaveable { mutableStateOf(false) }
    val state by vm.state.collectAsStateWithLifecycle(initialValue = null)
    val offRejectedMessage = stringResource(R.string.device_settings_anc_off_rejected_message)
+    val chargeCapRejectedMessage = stringResource(R.string.device_settings_charge_cap_rejected_message)

    LaunchedEffect(Unit) {
        vm.events.collect { event ->
@@ -105,6 +107,10 @@ fun DeviceSettingsScreenHost(
                DeviceSettingsViewModel.Event.OffModeRejectedByDevice -> {
                    snackbarHostState.showSnackbar(offRejectedMessage)
                }
+
+                DeviceSettingsViewModel.Event.DynamicEndOfChargeRejectedByDevice -> {
+                    snackbarHostState.showSnackbar(chargeCapRejectedMessage)
+                }
            }
        }
    }
@@ -139,6 +145,7 @@ fun DeviceSettingsScreenHost(
        onListeningModeCycleChange = { vm.setListeningModeCycle(it) },
        onAllowOffOptionChange = { vm.setAllowOffOption(it) },
        onSleepDetectionChange = { vm.setSleepDetection(it) },
+        onDynamicEndOfChargeChange = { vm.setDynamicEndOfCharge(it) },
        onDeviceNameChange = { vm.setDeviceName(it) },
        onPressControlsClick = { vm.navToPressControls() },
        onForceConnect = { vm.forceConnect() },
@@ -175,6 +182,7 @@ fun DeviceSettingsScreen(
    onListeningModeCycleChange: (Int) -> Unit = {},
    onAllowOffOptionChange: (Boolean) -> Unit = {},
    onSleepDetectionChange: (Boolean) -> Unit = {},
+    onDynamicEndOfChargeChange: (Boolean) -> Unit = {},
    onDeviceNameChange: (String) -> Unit = {},
    onPressControlsClick: () -> Unit = {},
    onForceConnect: () -> Unit = {},
@@ -389,6 +397,19 @@ fun DeviceSettingsScreen(
                    }
                }

+                // ── Battery ──────────────────────────────────
+                if (features.hasDynamicEndOfCharge && device.dynamicEndOfCharge != null) {
+                    item("battery_section") {
+                        BatteryCard(
+                            device = device,
+                            features = features,
+                            enabled = enabled,
+                            onDynamicEndOfChargeChange = onDynamicEndOfChargeChange,
+                            onOpenIssueTracker = onOpenIssueTracker,
+                        )
+                    }
+                }
+
                // ── Connections ───────────────────────────────
                val connectedDevices = device.connectedDevices
                if (connectedDevices != null && connectedDevices.devices.isNotEmpty()) {
@@ -475,6 +496,7 @@ internal fun previewFullState(isPro: Boolean) = DeviceSettingsViewModel.State(
                    muteMic = AapSetting.EndCallMuteMic.MuteMicMode.DOUBLE_PRESS,
                    endCall = AapSetting.EndCallMuteMic.EndCallMode.SINGLE_PRESS,
                ),
+                AapSetting.DynamicEndOfCharge::class to AapSetting.DynamicEndOfCharge(enabled = true),
            ),
        ),
    ),
@@ -79,6 +79,7 @@ class DeviceSettingsViewModel @Inject constructor(
        data class SendFailed(val command: AapCommand, val message: String?) : Event
        data object SystemRenameUnavailable : Event
        data object OffModeRejectedByDevice : Event
+        data object DynamicEndOfChargeRejectedByDevice : Event
    }

    val events = SingleEventFlow<Event>()
@@ -91,6 +92,16 @@ class DeviceSettingsViewModel @Inject constructor(
                }
            }
        }
+        launch {
+            aapManager.settingRejectedEvents.collect { (address, command) ->
+                if (address != currentAddress()) return@collect
+                when (command) {
+                    is AapCommand.SetDynamicEndOfCharge ->
+                        events.tryEmit(Event.DynamicEndOfChargeRejectedByDevice)
+                    else -> Unit // Other rejected commands handled elsewhere (e.g. ANC OFF)
+                }
+            }
+        }
    }

    val state = targetProfileId.flatMapLatest { profileId ->
@@ -285,6 +296,8 @@ class DeviceSettingsViewModel @Inject constructor(

    fun setSleepDetection(enabled: Boolean) = send(AapCommand.SetSleepDetection(enabled))

+    fun setDynamicEndOfCharge(enabled: Boolean) = send(AapCommand.SetDynamicEndOfCharge(enabled))
+
    fun setDeviceName(name: String) = launch {
        val address = currentAddress() ?: return@launch
        try {
@@ -0,0 +1,85 @@
+package eu.darken.capod.main.ui.devicesettings.cards
+
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.twotone.BatteryChargingFull
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.res.stringResource
+import eu.darken.capod.R
+import eu.darken.capod.common.compose.Preview2
+import eu.darken.capod.common.compose.PreviewWrapper
+import eu.darken.capod.common.settings.InfoBoxType
+import eu.darken.capod.common.settings.SettingsInfoBox
+import eu.darken.capod.common.settings.SettingsSection
+import eu.darken.capod.common.settings.SettingsSwitchItem
+import eu.darken.capod.main.ui.devicesettings.previewFullState
+import eu.darken.capod.monitor.core.PodDevice
+import eu.darken.capod.pods.core.apple.PodModel
+import eu.darken.capod.pods.core.apple.aap.protocol.AapSetting
+
+/**
+ * Apple's "Optimized Charge Limit" toggle (AAP setting 0x3B), shown for models that advertise
+ * [PodModel.Features.hasDynamicEndOfCharge]. The wire format follows the Apple-bool convention
+ * used by every other boolean setting. The experimental warning renders below the toggle and
+ * only when enabled — consistent with Sleep Detection and Personalized Volume in the rest of
+ * the app.
+ */
+@Composable
+internal fun BatteryCard(
+    device: PodDevice,
+    features: PodModel.Features,
+    enabled: Boolean,
+    onDynamicEndOfChargeChange: (Boolean) -> Unit = {},
+    onOpenIssueTracker: () -> Unit = {},
+) {
+    if (!features.hasDynamicEndOfCharge) return
+    val cap = device.dynamicEndOfCharge ?: return
+
+    SettingsSection(title = stringResource(R.string.device_settings_category_battery_label)) {
+        SettingsSwitchItem(
+            icon = Icons.TwoTone.BatteryChargingFull,
+            title = stringResource(R.string.device_settings_charge_cap_label),
+            subtitle = stringResource(R.string.device_settings_charge_cap_description),
+            checked = cap.enabled,
+            onCheckedChange = onDynamicEndOfChargeChange,
+            enabled = enabled,
+        )
+        if (cap.enabled) {
+            SettingsInfoBox(
+                title = stringResource(R.string.device_settings_experimental_title),
+                text = stringResource(R.string.device_settings_experimental_description),
+                type = InfoBoxType.WARNING,
+                action = {
+                    TextButton(onClick = onOpenIssueTracker) {
+                        Text(stringResource(R.string.device_settings_experimental_action))
+                    }
+                },
+            )
+        }
+    }
+}
+
+@Preview2
+@Composable
+private fun BatteryCardEnabledPreview() = PreviewWrapper {
+    val state = previewFullState(isPro = true)
+    val device = state.device!!
+    BatteryCard(
+        device = device,
+        features = PodModel.Features(hasDynamicEndOfCharge = true),
+        enabled = true,
+    )
+}
+
+@Preview2
+@Composable
+private fun BatteryCardDisabledPreview() = PreviewWrapper {
+    val state = previewFullState(isPro = true)
+    val device = state.device!!
+    BatteryCard(
+        device = device,
+        features = PodModel.Features(hasDynamicEndOfCharge = true),
+        enabled = false,
+    )
+}
@@ -61,6 +61,7 @@ import eu.darken.capod.common.compose.PreviewWrapper
 import eu.darken.capod.common.compose.preview.MockPodDataProvider
 import eu.darken.capod.monitor.core.PodDevice
 import eu.darken.capod.monitor.core.cachedBatteryFormatted
+import eu.darken.capod.pods.core.apple.aap.AapPodState
 import eu.darken.capod.pods.core.apple.aap.protocol.AapSetting
 import eu.darken.capod.pods.core.apple.ble.devices.DualApplePods
 import eu.darken.capod.pods.core.apple.ble.devices.DualApplePods.LidState
@@ -227,7 +228,8 @@ private fun ColumnScope.DualPodsCardExpanded(
                PodGauge(
                    iconRes = device.leftPodIcon,
                    batteryPercent = device.batteryLeft.toBatteryFloat(),
-                    isCharging = device.isLeftPodCharging ?: false,
+                    chargingState = device.leftPodChargingState
+                        ?: device.isLeftPodCharging?.let { if (it) AapPodState.ChargingState.CHARGING else null },
                    isInEar = device.isLeftInEar ?: false,
                    showEarDetection = device.hasEarDetection && device.hasDualPods,
                    isMicrophone = device.isLeftPodMicrophone ?: false,
@@ -238,7 +240,8 @@ private fun ColumnScope.DualPodsCardExpanded(
                PodGauge(
                    iconRes = device.rightPodIcon,
                    batteryPercent = device.batteryRight.toBatteryFloat(),
-                    isCharging = device.isRightPodCharging ?: false,
+                    chargingState = device.rightPodChargingState
+                        ?: device.isRightPodCharging?.let { if (it) AapPodState.ChargingState.CHARGING else null },
                    isInEar = device.isRightInEar ?: false,
                    showEarDetection = device.hasEarDetection && device.hasDualPods,
                    isMicrophone = device.isRightPodMicrophone ?: false,
@@ -292,7 +295,7 @@ private fun ColumnScope.DualPodsCardExpanded(
 private fun PodGauge(
    iconRes: Int,
    batteryPercent: Float,
-    isCharging: Boolean,
+    chargingState: AapPodState.ChargingState?,
    isInEar: Boolean,
    showEarDetection: Boolean,
    isMicrophone: Boolean,
@@ -370,12 +373,13 @@ private fun PodGauge(

        // Status chips
        StatusChipRow(
-            isCharging = isCharging,
+            chargingState = chargingState,
            isInEar = isInEar,
            showEarDetection = showEarDetection,
            isMicrophone = isMicrophone,
            showMicrophone = showMicrophone,
            chargingLabel = stringResource(R.string.pods_charging_label),
+            chargingOptimizedLabel = stringResource(R.string.pods_charging_optimized_label),
            inEarLabel = stringResource(R.string.pods_inear_label),
            microphoneLabel = stringResource(R.string.pods_microphone_label),
        )
@@ -420,11 +424,17 @@ private fun CaseRow(
            horizontalArrangement = Arrangement.spacedBy(4.dp),
            verticalArrangement = Arrangement.spacedBy(4.dp),
        ) {
-            if (device.isCaseCharging == true) {
-                StatusChip(
+            when (val caseState = device.caseChargingState
+                ?: device.isCaseCharging?.let { if (it) AapPodState.ChargingState.CHARGING else null }) {
+                AapPodState.ChargingState.CHARGING_OPTIMIZED -> StatusChip(
+                    icon = Icons.TwoTone.BatteryChargingFull,
+                    label = stringResource(R.string.pods_charging_optimized_label),
+                )
+                AapPodState.ChargingState.CHARGING -> StatusChip(
                    icon = Icons.TwoTone.BatteryChargingFull,
                    label = stringResource(R.string.pods_charging_label),
                )
+                else -> Unit
            }

            val lidState = device.caseLidState
@@ -58,6 +58,7 @@ import eu.darken.capod.common.compose.PreviewWrapper
 import eu.darken.capod.common.compose.preview.MockPodDataProvider
 import eu.darken.capod.monitor.core.PodDevice
 import eu.darken.capod.monitor.core.cachedBatteryFormatted
+import eu.darken.capod.pods.core.apple.aap.AapPodState
 import eu.darken.capod.pods.core.apple.aap.protocol.AapSetting
 import eu.darken.capod.pods.core.apple.ble.formatBatteryPercent
 import java.time.Instant
@@ -267,11 +268,17 @@ private fun ColumnScope.SinglePodsCardExpanded(
                horizontalArrangement = Arrangement.spacedBy(4.dp),
                verticalArrangement = Arrangement.spacedBy(4.dp),
            ) {
-                if (device.isHeadsetBeingCharged == true) {
-                    StatusChip(
+                when (val headsetState = device.headsetChargingState
+                    ?: device.isHeadsetBeingCharged?.let { if (it) AapPodState.ChargingState.CHARGING else null }) {
+                    AapPodState.ChargingState.CHARGING_OPTIMIZED -> StatusChip(
+                        icon = Icons.TwoTone.BatteryChargingFull,
+                        label = stringResource(R.string.pods_charging_optimized_label),
+                    )
+                    AapPodState.ChargingState.CHARGING -> StatusChip(
                        icon = Icons.TwoTone.BatteryChargingFull,
                        label = stringResource(R.string.pods_charging_label),
                    )
+                    else -> Unit
                }
                if (device.isBeingWorn == true) {
                    StatusChip(
@@ -25,6 +25,7 @@ import androidx.compose.ui.graphics.vector.ImageVector
 import androidx.compose.ui.unit.dp
 import eu.darken.capod.common.compose.Preview2
 import eu.darken.capod.common.compose.PreviewWrapper
+import eu.darken.capod.pods.core.apple.aap.AapPodState

@Composable
 fun StatusChip(
@@ -60,12 +61,13 @@ fun StatusChip(
@OptIn(ExperimentalLayoutApi::class)
@Composable
 fun StatusChipRow(
-    isCharging: Boolean,
+    chargingState: AapPodState.ChargingState?,
    isInEar: Boolean,
    showEarDetection: Boolean,
    isMicrophone: Boolean,
    showMicrophone: Boolean,
    chargingLabel: String,
+    chargingOptimizedLabel: String,
    inEarLabel: String,
    microphoneLabel: String,
    modifier: Modifier = Modifier,
@@ -75,11 +77,16 @@ fun StatusChipRow(
        horizontalArrangement = Arrangement.spacedBy(4.dp),
        verticalArrangement = Arrangement.spacedBy(4.dp),
    ) {
-        if (isCharging) {
-            StatusChip(
+        when (chargingState) {
+            AapPodState.ChargingState.CHARGING_OPTIMIZED -> StatusChip(
+                icon = Icons.TwoTone.BatteryChargingFull,
+                label = chargingOptimizedLabel,
+            )
+            AapPodState.ChargingState.CHARGING -> StatusChip(
                icon = Icons.TwoTone.BatteryChargingFull,
                label = chargingLabel,
            )
+            else -> Unit
        }
        if (showMicrophone && isMicrophone) {
            StatusChip(
@@ -106,12 +113,29 @@ private fun StatusChipChargingPreview() = PreviewWrapper {
@Composable
 private fun StatusChipRowAllPreview() = PreviewWrapper {
    StatusChipRow(
-        isCharging = true,
+        chargingState = AapPodState.ChargingState.CHARGING,
        isInEar = true,
        showEarDetection = true,
        isMicrophone = true,
        showMicrophone = true,
        chargingLabel = "Charging",
+        chargingOptimizedLabel = "Optimized",
+        inEarLabel = "In Ear",
+        microphoneLabel = "Mic",
+    )
+}
+
+@Preview2
+@Composable
+private fun StatusChipRowOptimizedPreview() = PreviewWrapper {
+    StatusChipRow(
+        chargingState = AapPodState.ChargingState.CHARGING_OPTIMIZED,
+        isInEar = false,
+        showEarDetection = true,
+        isMicrophone = true,
+        showMicrophone = true,
+        chargingLabel = "Charging",
+        chargingOptimizedLabel = "Optimized",
        inEarLabel = "In Ear",
        microphoneLabel = "Mic",
    )
@@ -85,6 +85,7 @@ data class PodDevice(
    val hasEarDetection: Boolean get() = model.features.hasEarDetection
    val hasAncControl: Boolean get() = model.features.hasAncControl
    val hasDualMicrophone: Boolean get() = ble is HasDualMicrophone
+    val hasDynamicEndOfCharge: Boolean get() = model.features.hasDynamicEndOfCharge

    // Signal / timing
    val seenLastAt: Instant?
@@ -186,6 +187,15 @@ data class PodDevice(
    val isHeadsetBeingCharged: Boolean?
        get() = aap?.isHeadsetCharging ?: (ble as? HasChargeDetection)?.isHeadsetBeingCharged ?: cached?.isHeadsetCharging

+    // Full per-slot charging state — AAP only (BLE + cache don't carry CHARGING_OPTIMIZED).
+    // Null means "no live AAP reading", which lets callers avoid showing a stale Optimized chip
+    // after the device went out of range. Existing isLeftCharging/etc. remain the Boolean
+    // collapse of CHARGING + CHARGING_OPTIMIZED for everyone who just cares "is it charging".
+    val leftPodChargingState: AapPodState.ChargingState? get() = aap?.leftChargingState
+    val rightPodChargingState: AapPodState.ChargingState? get() = aap?.rightChargingState
+    val caseChargingState: AapPodState.ChargingState? get() = aap?.caseChargingState
+    val headsetChargingState: AapPodState.ChargingState? get() = aap?.headsetChargingState
+
    // Resolved primary pod: AAP cmd 0x08 preferred, BLE bit 5 fallback.
    private val resolvedPrimaryPod: DualBlePodSnapshot.Pod?
        get() = aap?.aapPrimaryPod?.pod?.let { aapPod ->
@@ -337,6 +347,9 @@ data class PodDevice(
    val sleepDetection: AapSetting.SleepDetection?
        get() = aap?.setting()

+    val dynamicEndOfCharge: AapSetting.DynamicEndOfCharge?
+        get() = aap?.setting()
+
    val connectedDevices: AapSetting.ConnectedDevices?
        get() = aap?.setting()

@@ -232,6 +232,7 @@ enum class PodModel(
            hasAllowOffOption = true,
            hasStemConfig = true,
            hasSleepDetection = true,
+            hasDynamicEndOfCharge = true,
        ),
        modelNumbers = setOf("A3063", "A3064", "A3065"), // earphones
        leftPodIconRes = R.drawable.device_airpods_pro2_left,
@@ -558,5 +559,12 @@ enum class PodModel(
        val hasAllowOffOption: Boolean = false,
        val hasStemConfig: Boolean = false,
        val hasSleepDetection: Boolean = false,
+        /**
+         * Apple's "Optimized Charge Limit" (AAP setting 0x3B). Distinct from the older
+         * "Optimized Battery Charging" — that earlier feature isn't exposed as a toggleable
+         * AAP setting. Enable on any model that's been confirmed (via capture) to push 0x3B
+         * on connect and accept writes to it.
+         */
+        val hasDynamicEndOfCharge: Boolean = false,
    )
 }
@@ -68,6 +68,17 @@ class AapConnectionManager @Inject constructor(
    private val _offRejectedEvents = MutableSharedFlow<BluetoothAddress>(extraBufferCapacity = 16)
    val offRejectedEvents: SharedFlow<BluetoothAddress> = _offRejectedEvents.asSharedFlow()

+    /**
+     * Emits when any setting command failed verification on the device side. Unlike
+     * [offRejectedEvents] this covers every rejected write (including the ANC-OFF case); UI
+     * consumers filter by the command type they care about — e.g. the charge-cap toggle shows
+     * a snackbar only for [AapCommand.SetDynamicEndOfCharge].
+     */
+    private val _settingRejectedEvents =
+        MutableSharedFlow<Pair<BluetoothAddress, AapCommand>>(extraBufferCapacity = 16)
+    val settingRejectedEvents: SharedFlow<Pair<BluetoothAddress, AapCommand>> =
+        _settingRejectedEvents.asSharedFlow()
+
    fun deviceState(address: BluetoothAddress) = _allStates.map { it[address] }

    suspend fun connect(
@@ -119,6 +130,14 @@ class AapConnectionManager @Inject constructor(
                }
            }

+            // Forward generic setting-rejection events from this connection (child coroutine).
+            // Covers every rejected write — consumers filter by the command they care about.
+            launch {
+                connection.settingRejected.collect { command ->
+                    _settingRejectedEvents.tryEmit(address to command)
+                }
+            }
+
            connection.state.collect { podState ->
                if (podState.connectionState == AapPodState.ConnectionState.DISCONNECTED) {
                    log(TAG) { "Connection to $address disconnected" }
@@ -53,6 +53,13 @@ data class AapPodState(
    val batteryCase: Float? get() = batteries[BatteryType.CASE]?.percent
    val batteryHeadset: Float? get() = batteries[BatteryType.SINGLE]?.percent

+    // Raw charging state per slot — the full enum, not collapsed to a Boolean. Lets the UI
+    // distinguish CHARGING_OPTIMIZED ("Optimized Charge Limit in effect") from plain CHARGING.
+    val leftChargingState: ChargingState? get() = batteries[BatteryType.LEFT]?.charging
+    val rightChargingState: ChargingState? get() = batteries[BatteryType.RIGHT]?.charging
+    val caseChargingState: ChargingState? get() = batteries[BatteryType.CASE]?.charging
+    val headsetChargingState: ChargingState? get() = batteries[BatteryType.SINGLE]?.charging
+
    // Charging state from AAP battery
    val isLeftCharging: Boolean?
        get() = batteries[BatteryType.LEFT]?.let { it.charging == ChargingState.CHARGING || it.charging == ChargingState.CHARGING_OPTIMIZED }
@@ -46,6 +46,7 @@ internal class AapConnection(
    val keysReceived: SharedFlow<KeyExchangeResult> get() = engine.keysReceived
    val stemPressEvents: SharedFlow<StemPressEvent> get() = engine.stemPressEvents
    val offRejected: SharedFlow<Unit> get() = engine.offRejected
+    val settingRejected: SharedFlow<AapCommand> get() = engine.settingRejected

    private var socket: BluetoothSocket? = null
    private var readerJob: Job? = null
@@ -35,7 +35,11 @@ internal class AapOutboundController(
        runtimeState: OutboundRuntimeState,
        command: AapCommand,
    ): OutboundDecision {
-        if (command !is AapCommand.SetDeviceName) {
+        // SetDeviceName and SetDynamicEndOfCharge bypass ear-gating:
+        //  - Rename is a user-initiated metadata change, independent of wear state.
+        //  - Charge cap (setting 0x3B) is toggled while pods sit in the closed case; queueing
+        //    it until worn would make the toggle look broken for its main use case.
+        if (command !is AapCommand.SetDeviceName && command !is AapCommand.SetDynamicEndOfCharge) {
            val earDetection = podState.setting<AapSetting.EarDetection>()
            if (earDetection != null && !earDetection.isEitherPodInEar) {
                val result = coordinator.enqueue(runtimeState.pendingCommands, command, podState)
@@ -53,6 +53,16 @@ internal class AapSessionEngine(
        MutableSharedFlow<Unit>(extraBufferCapacity = 1, onBufferOverflow = BufferOverflow.DROP_OLDEST)
    val offRejected: SharedFlow<Unit> = _offRejected.asSharedFlow()

+    /**
+     * Fires whenever a write command fails verification after the coordinator's single retry —
+     * i.e. the device neither echoed the expected state nor retried into a matching one.
+     * Separate from [offRejected] which is specialised for the ANC-OFF UX path. Consumers filter
+     * by the command type they care about (e.g. the charge-cap toggle shows a snackbar).
+     */
+    private val _settingRejected =
+        MutableSharedFlow<AapCommand>(extraBufferCapacity = 4, onBufferOverflow = BufferOverflow.DROP_OLDEST)
+    val settingRejected: SharedFlow<AapCommand> = _settingRejected.asSharedFlow()
+
    private val hidTracker = HidTracker { msg -> log(TAG) { msg } }
    private val inboundInterpreter = AapInboundInterpreter(profile)
    private val ancController = AapAncController()
@@ -419,10 +429,12 @@ internal class AapSessionEngine(
    }

    private fun handleRejectedCommand(command: AapCommand?) {
+        if (command == null) return
        if (command is AapCommand.SetAncMode && command.mode == AapSetting.AncMode.Value.OFF) {
            applyAncDecision(ancController.onOffRejected(_state.value, runtimeState.anc))
            _offRejected.tryEmit(Unit)
        }
+        _settingRejected.tryEmit(command)
    }

    private fun scheduleTimer(key: EngineTimerKey, delayMs: Long) {
@@ -172,6 +172,10 @@ internal class AapSettingsCoordinator(
                AapSetting.SleepDetection::class to AapSetting.SleepDetection(enabled = command.enabled)
            }

+            is AapCommand.SetDynamicEndOfCharge -> {
+                AapSetting.DynamicEndOfCharge::class to AapSetting.DynamicEndOfCharge(enabled = command.enabled)
+            }
+
            is AapCommand.SetDeviceName -> {
                val currentInfo = baseState.deviceInfo ?: return null
                return baseState.copy(
@@ -205,6 +209,7 @@ internal class AapSettingsCoordinator(
        is AapCommand.SetAllowOffOption -> { s -> s.setting<AapSetting.AllowOffOption>()?.enabled == command.enabled }
        is AapCommand.SetStemConfig -> { s -> s.setting<AapSetting.StemConfig>()?.claimedPressMask == command.claimedPressMask }
        is AapCommand.SetSleepDetection -> { s -> s.setting<AapSetting.SleepDetection>()?.enabled == command.enabled }
+        is AapCommand.SetDynamicEndOfCharge -> { s -> s.setting<AapSetting.DynamicEndOfCharge>()?.enabled == command.enabled }
        is AapCommand.SetDeviceName -> null
    }
 }
@@ -34,5 +34,6 @@ sealed class AapCommand {
    data class SetAllowOffOption(val enabled: Boolean) : AapCommand()
    data class SetStemConfig(val claimedPressMask: Int) : AapCommand()
    data class SetSleepDetection(val enabled: Boolean) : AapCommand()
+    data class SetDynamicEndOfCharge(val enabled: Boolean) : AapCommand()
    data class SetDeviceName(val name: String) : AapCommand()
 }
@@ -146,6 +146,15 @@ sealed class AapSetting {
        val enabled: Boolean,
    ) : AapSetting()

+    /**
+     * Apple's "Optimized Charge Limit" — AAP setting 0x3B, Apple-bool encoding. Distinct
+     * from the older "Optimized Battery Charging" which Apple doesn't expose as a
+     * user-controllable AAP setting. Supported models push this value on connect.
+     */
+    data class DynamicEndOfCharge(
+        val enabled: Boolean,
+    ) : AapSetting()
+
    data class InCaseTone(
        val enabled: Boolean,
    ) : AapSetting()
@@ -33,7 +33,6 @@ class DefaultAapDeviceProfile(
            AapControlId.HEARING_ASSIST.value,              // 0x33
            AapControlId.HEARING_PROTECTION_PPE.value,      // 0x37
            AapControlId.PPE_CAP_LEVEL_CONFIG.value,        // 0x38
-            AapControlId.DYNAMIC_END_OF_CHARGE.value,       // 0x3B
            AapControlId.UPLINK_EQ_BUD.value,               // 0x3E
        )

@@ -99,6 +98,7 @@ class DefaultAapDeviceProfile(
        is AapCommand.SetAllowOffOption -> buildSettingsMessage(AapControlId.ALLOW_OFF_OPTION.value, encodeAppleBool(command.enabled))
        is AapCommand.SetStemConfig -> buildSettingsMessage(AapControlId.RAW_GESTURES_CONFIG.value, command.claimedPressMask and 0x0F)
        is AapCommand.SetSleepDetection -> buildSettingsMessage(AapControlId.SLEEP_DETECTION.value, encodeAppleBool(command.enabled))
+        is AapCommand.SetDynamicEndOfCharge -> buildSettingsMessage(AapControlId.DYNAMIC_END_OF_CHARGE.value, encodeAppleBool(command.enabled))
        is AapCommand.SetDeviceName -> buildRenameMessage(command.name)
    }

@@ -263,6 +263,14 @@ class DefaultAapDeviceProfile(
                val enabled = decodeAppleBool(value) ?: return null
                AapSetting.SleepDetection::class to AapSetting.SleepDetection(enabled)
            }
+            AapControlId.DYNAMIC_END_OF_CHARGE.value -> {
+                // Apple's "Optimized Charge Limit" — Pro 3 pushes this on connect as value 0x01
+                // (enabled). decodeAppleBool rejects anything that isn't a confirmed bool so
+                // unknown encodings fall through to UnknownSetting logging rather than being
+                // coerced to false.
+                val enabled = decodeAppleBool(value) ?: return null
+                AapSetting.DynamicEndOfCharge::class to AapSetting.DynamicEndOfCharge(enabled)
+            }
            AapControlId.IN_CASE_TONE.value -> {
                // Decoded internally (never exposed in UI) to keep lastMessageAt fresh.
                // Originally labeled "Charging Sounds" — the real case tones are controlled
@@ -283,6 +283,7 @@
    <string name="pods_unknown_contact_dev">This is an unknown device, but it is using similar message format. Let\'s add support for it, contact me :)</string>
    <string name="pods_none_label_short">No device</string>
    <string name="pods_charging_label">Charging</string>
+    <string name="pods_charging_optimized_label">Optimized</string>
    <string name="pods_inear_label">In ear</string>
    <string name="pods_microphone_label">Microphone</string>
    <string name="anc_mode_off">Off</string>
@@ -544,6 +545,10 @@
    <string name="device_settings_rename_system_unavailable_bt_settings_action">Bluetooth Settings</string>
    <string name="device_settings_send_failed">Could not apply setting: %1$s</string>
    <string name="device_settings_anc_off_rejected_message">Off mode isn\'t enabled on this device. Enable \"Allow Off mode\" under Noise Control.</string>
+    <string name="device_settings_category_battery_label">Battery</string>
+    <string name="device_settings_charge_cap_label">Optimized Charge Limit</string>
+    <string name="device_settings_charge_cap_description">Learn your routine and pause charging around 80%% to extend battery life, topping the pods off before you\'re likely to use them.</string>
+    <string name="device_settings_charge_cap_rejected_message">Optimized Charge Limit couldn\'t be changed. This is an experimental feature — please report if it keeps failing.</string>
    <string name="device_settings_category_connections_label">Connected Devices</string>
    <string name="device_settings_connected_devices_description">Other devices currently connected to these AirPods</string>
    <string name="device_settings_connected_device_label">Device %d</string>
@@ -117,6 +117,20 @@ class DefaultAapDeviceProfileNewSettingsTest : BaseAapSessionTest() {
        @Test fun `decode unknown returns null`() { profile.decodeSetting(settingsMessage(0x35, 0x00)).shouldBeNull() }
    }

+    // ── Dynamic End of Charge / "Optimized Charge Limit" (0x3B) ─
+    // Apple-bool wire semantics matching every other boolean setting we've decoded. Real
+    // capture on a Pro 3 after handshake showed rawValue 0x01 (enabled).
+
+    @Nested
+    inner class DynamicEndOfChargeTests {
+        @Test fun `encode enabled`() { profile.encodeCommand(AapCommand.SetDynamicEndOfCharge(true))[7] shouldBe 0x01.toByte() }
+        @Test fun `encode disabled`() { profile.encodeCommand(AapCommand.SetDynamicEndOfCharge(false))[7] shouldBe 0x02.toByte() }
+        @Test fun `encode carries the right setting id`() { profile.encodeCommand(AapCommand.SetDynamicEndOfCharge(true))[6] shouldBe 0x3B.toByte() }
+        @Test fun `decode enabled`() { decodeSetting<AapSetting.DynamicEndOfCharge>(settingsMessage(0x3B, 0x01)).enabled shouldBe true }
+        @Test fun `decode disabled`() { decodeSetting<AapSetting.DynamicEndOfCharge>(settingsMessage(0x3B, 0x02)).enabled shouldBe false }
+        @Test fun `decode unknown returns null`() { profile.decodeSetting(settingsMessage(0x3B, 0x00)).shouldBeNull() }
+    }
+
    // ── In-Case Tone (0x31) ─────────────────────────────────
    // Decode path is kept internally even though the setting is no longer exposed in the UI.
    // See the IN_CASE_TONE branch in DefaultAapDeviceProfile.decodeSetting for rationale.
@@ -171,6 +171,28 @@ class AirPodsPro3AapSessionTest : BaseAapSessionTest() {
        @Test fun `NC one airpod OFF`() {
            decodeSetting<AapSetting.NcWithOneAirPod>("04 00 04 00 09 00 1B 02 00 00 00").enabled shouldBe false
        }
+
+        // DynamicEndOfCharge — Apple's "Optimized Charge Limit", setting 0x3B. Real capture
+        // from a Pro 3 after handshake showed rawValue=0x01 (enabled). Apple-bool semantics
+        // are our current assumption; decodeAppleBool rejects values that aren't 0x01/0x02.
+        @Test fun `dynamic end of charge ON - observed on connect`() {
+            decodeSetting<AapSetting.DynamicEndOfCharge>("04 00 04 00 09 00 3B 01 00 00 00").enabled shouldBe true
+        }
+
+        @Test fun `dynamic end of charge OFF`() {
+            decodeSetting<AapSetting.DynamicEndOfCharge>("04 00 04 00 09 00 3B 02 00 00 00").enabled shouldBe false
+        }
+
+        @Test fun `dynamic end of charge - unknown raw value is not decoded as bool`() {
+            // 0x00 isn't Apple-bool — decoder must fall through (return null) instead of
+            // silently coercing to false. This keeps us honest about the wire format and
+            // lets the unhandled-setting path log the raw bytes for follow-up.
+            profile.decodeSetting(
+                eu.darken.capod.pods.core.apple.aap.protocol.AapPacket.Message.parse(
+                    byteArrayOf(0x04, 0x00, 0x04, 0x00, 0x09, 0x00, 0x3B, 0x00, 0x00, 0x00, 0x00)
+                )!!
+            ).shouldBeNull()
+        }
    }

    // ── ANC Mode Switching (verified audible) ────────────────
@@ -252,7 +274,9 @@ class AirPodsPro3AapSessionTest : BaseAapSessionTest() {

        @Test
        fun `unconfirmed settings IDs decode as UnknownSetting`() {
-            val unconfirmedIds = listOf(0x29, 0x2C, 0x2F, 0x33, 0x30, 0x37, 0x38, 0x3B)
+            // 0x3B (DYNAMIC_END_OF_CHARGE) was previously on this list but has since been
+            // promoted to the DynamicEndOfCharge decoder — see DynamicEndOfCharge tests above.
+            val unconfirmedIds = listOf(0x29, 0x2C, 0x2F, 0x33, 0x30, 0x37, 0x38)
            for (id in unconfirmedIds) {
                val setting = decodeSetting<AapSetting.UnknownSetting>(settingsMessage(id, 0x01))
                setting.settingId shouldBe id
@@ -280,6 +280,27 @@ class AapSessionEngineTest : BaseTest() {
            engineWithEar.state.value.pendingSettingsCount shouldBe 1
        }

+        @Test
+        fun `send bypasses ear gate for SetDynamicEndOfCharge`() = runTest(UnconfinedTestDispatcher()) {
+            // Unlike most settings, the charge-cap toggle is used while pods sit in the
+            // closed case. Queueing it until worn would make the toggle look broken.
+            val profile = mockProfile {
+                every { decodeSetting(any()) } returns (AapSetting.EarDetection::class as KClass<out AapSetting> to AapSetting.EarDetection(
+                    primaryPod = AapSetting.EarDetection.PodPlacement.IN_CASE,
+                    secondaryPod = AapSetting.EarDetection.PodPlacement.IN_CASE,
+                ))
+            }
+            val engine = AapSessionEngine(profile, timeSource)
+            engine.startReady(this as TestScope)
+            engine.processMessage(dummyMessage()) // Set ear detection to IN_CASE
+
+            val sentCommands = mutableListOf<AapCommand>()
+            engine.send(AapCommand.SetDynamicEndOfCharge(false)) { sentCommands.add(it) }
+
+            sentCommands shouldBe listOf(AapCommand.SetDynamicEndOfCharge(false))
+            engine.state.value.pendingSettingsCount shouldBe 0
+        }
+
        @Test
        fun `send immediate when pod in ear`() = runTest(UnconfinedTestDispatcher()) {
            val profile = mockProfile {