refactor(reaction): Switch to sticky resume flag with opt-in cold-wear

Replaces the origin-tracking machinery with a simpler model that matches Apple's iOS/macOS behavior: auto-play strictly resumes a CAP-dispatched pause, gated by a sticky boolean cleared on inactive→active transitions. The original fire-on-cold-wear behavior is preserved as a per-device opt-in 'Start music on wear' setting.
2026-09-16 11:16:12 -04:00 · 2026-05-07 14:08:22 +02:00
parent 278257998b
commit 17663bc759
10 changed files with 273 additions and 359 deletions
@@ -15,23 +15,34 @@ class MediaControl @Inject constructor(
    private val audioManager: AudioManager,
    private val timeSource: TimeSource,
 ) {
-    private var capPauseExpiryElapsedRealtime: Long = 0L
-
-    private val transitionLock = Any()
-
+    /**
+     * Set when [sendPause] dispatches a pause we expect to take effect, cleared when [sendPlay]
+     * dispatches a resume or when music transitions inactive→active from any source. Read by
+     * [PlayPause] to gate auto-resume on pod-in: only resume if we're the ones who paused.
+     *
+     * "Sticky" — no time-based expiry. The original 15-second window was too short for typical
+     * pod-out conversations and had a known race where music starting again via another source
+     * (e.g. user manually resumed) could trigger a stray play-key dispatch on the next pod-in.
+     */
+    @Volatile private var capPaused: Boolean = false
    @Volatile private var lastKnownMusicActive: Boolean = false
-    @Volatile private var externalStopAt: Long = NO_TIMESTAMP
-    @Volatile private var capPauseDispatchedAt: Long = NO_TIMESTAMP

    private val playbackCallback = object : AudioManager.AudioPlaybackCallback() {
        override fun onPlaybackConfigChanged(configs: List<AudioPlaybackConfiguration>) {
-            recordTransition(audioManager.isMusicActive)
+            val nowActive = audioManager.isMusicActive
+            if (!lastKnownMusicActive && nowActive) {
+                // Music started by some source (could be us via sendPlay or someone else).
+                // Either way, our pause memory is stale — drop it so a future pod-in doesn't
+                // re-fire a play key over already-active music.
+                capPaused = false
+            }
+            lastKnownMusicActive = nowActive
        }
    }

    init {
-        // Seed from current state so we can't miss a true→false transition when
-        // MediaControl is constructed while music is already active.
+        // Seed the active flag from current state so we won't miss the next inactive→active
+        // transition if music is already playing when MediaControl is constructed.
        lastKnownMusicActive = audioManager.isMusicActive
        audioManager.registerAudioPlaybackCallback(playbackCallback, null)
    }
@@ -40,74 +51,27 @@ class MediaControl @Inject constructor(
        get() = audioManager.isMusicActive

    val wasRecentlyPausedByCap: Boolean
-        get() = capPauseExpiryElapsedRealtime > timeSource.elapsedRealtime()
-
-    /**
-     * `true` when music has been stopped recently by something *other* than CAP — i.e. the
-     * user paused via the phone, the playing app stopped on its own, or playback ended.
-     *
-     * Used by [PlayPause] to suppress auto-play on pod re-insertion when the user clearly
-     * wanted music to stay stopped. Stays `false` for stops attributed to CAP — those are
-     * detected by [recordTransition] from the pending [capPauseDispatchedAt] set by
-     * [sendPause].
-     */
-    val wasMusicExternallyStoppedRecently: Boolean
-        get() {
-            val nowActive = audioManager.isMusicActive
-            // Defense in depth: if the callback was missed (race, re-register, etc.), record
-            // the transition on read.
-            if (lastKnownMusicActive != nowActive) recordTransition(nowActive)
-            if (nowActive) return false
-            val stoppedAt = externalStopAt
-            return stoppedAt != NO_TIMESTAMP &&
-                timeSource.elapsedRealtime() - stoppedAt < EXTERNAL_STOP_WINDOW_MS
-        }
-
-    private fun recordTransition(nowActive: Boolean) = synchronized(transitionLock) {
-        if (lastKnownMusicActive && !nowActive) {
-            val now = timeSource.elapsedRealtime()
-            val pendingAt = capPauseDispatchedAt
-            val byCap = pendingAt != NO_TIMESTAMP &&
-                (now - pendingAt) < CAP_PAUSE_ATTRIBUTION_TTL_MS
-            if (byCap) {
-                // Consume the pending CAP attribution; clear any stale prior external stop
-                // since we're attributing the *current* state-of-music to CAP.
-                capPauseDispatchedAt = NO_TIMESTAMP
-                externalStopAt = NO_TIMESTAMP
-            } else {
-                externalStopAt = now
-                // Stale pending dispatch (TTL exceeded — pause was probably ignored). Drop it
-                // so a future stop isn't misattributed.
-                capPauseDispatchedAt = NO_TIMESTAMP
-            }
-        } else if (!lastKnownMusicActive && nowActive) {
-            // Music is active again — any pending CAP attribution is stale, and any prior
-            // external stop is no longer "recent" (music has been resumed since).
-            capPauseDispatchedAt = NO_TIMESTAMP
-            externalStopAt = NO_TIMESTAMP
-        }
-        lastKnownMusicActive = nowActive
-    }
+        get() = capPaused

    suspend fun sendPlay() {
        log(TAG, INFO) { "sendPlay()" }
-        if (audioManager.isMusicActive && !wasRecentlyPausedByCap) {
+        if (audioManager.isMusicActive && !capPaused) {
            log(TAG, INFO) { "Music is already playing, not sending play" }
            return
        }
        sendKey(KeyEvent.KEYCODE_MEDIA_PLAY)
-        clearRecentCapPause()
+        capPaused = false
    }

    /**
     * Dispatches a MEDIA_PAUSE key event if music is currently playing.
     *
-     * Returns `true` when a key event was actually dispatched (and the 15-second
-     * [wasRecentlyPausedByCap] window was set), `false` when the call was a no-op because
-     * nothing was playing. Callers that need to distinguish "we actually paused" from "there
-     * was nothing to pause" — e.g. the sleep reaction, which gates its notification and
-     * cooldown on a real pause — should branch on the return value rather than checking
-     * [isPlaying] themselves to avoid a check-then-act race with the audio system.
+     * Returns `true` when a key event was actually dispatched (and the [wasRecentlyPausedByCap]
+     * flag was set), `false` when the call was a no-op because nothing was playing. Callers that
+     * need to distinguish "we actually paused" from "there was nothing to pause" — e.g. the sleep
+     * reaction, which gates its notification and cooldown on a real pause — should branch on the
+     * return value rather than checking [isPlaying] themselves to avoid a check-then-act race
+     * with the audio system.
     */
    suspend fun sendPause(): Boolean {
        log(TAG, INFO) { "sendPause()" }
@@ -115,20 +79,19 @@ class MediaControl @Inject constructor(
            log(TAG, INFO) { "Music is not playing, not sending pause" }
            return false
        }
-        // Set BEFORE dispatch so the resulting active→inactive transition (whether observed
-        // by the playback callback or detected by the getter's read-time fallback) attributes
-        // the stop to CAP. Held under transitionLock for memory ordering against recordTransition.
-        synchronized(transitionLock) {
-            capPauseDispatchedAt = timeSource.elapsedRealtime()
-        }
+        // Set BEFORE the suspending sendKey() call. If we set after, an inactive→active
+        // playback callback that fires during the dispatch (e.g. a fast user resume on the
+        // phone, or another app grabbing audio focus and immediately starting) could clear
+        // capPaused, and then we'd overwrite it back to true on a stale pause — leaving the
+        // sticky flag set while music is genuinely playing.
+        capPaused = true
        sendKey(KeyEvent.KEYCODE_MEDIA_PAUSE)
-        markRecentCapPause()
        return true
    }

    suspend fun sendPlayPause() {
        log(TAG) { "sendPlayPause()" }
-        if (wasRecentlyPausedByCap) {
+        if (capPaused) {
            sendPlay()
            return
        }
@@ -174,23 +137,7 @@ class MediaControl @Inject constructor(
        )
    }

-    private fun markRecentCapPause() {
-        capPauseExpiryElapsedRealtime = timeSource.elapsedRealtime() + RECENT_CAP_PAUSE_WINDOW_MS
-    }
-
-    private fun clearRecentCapPause() {
-        capPauseExpiryElapsedRealtime = 0L
-    }
-
    companion object {
        private val TAG = logTag("MediaControl")
-        private const val RECENT_CAP_PAUSE_WINDOW_MS = 15_000L
-        private const val EXTERNAL_STOP_WINDOW_MS = 60_000L
-        // TTL for a pending CAP-pause attribution. Long enough to cover delayed/missed
-        // playback-config callbacks (the read-time fallback may fire many seconds later);
-        // short enough that an "ignored pause" doesn't wrongly claim a much later external
-        // stop as CAP-attributed.
-        private const val CAP_PAUSE_ATTRIBUTION_TTL_MS = 30_000L
-        private const val NO_TIMESTAMP = -1L
    }
 }
@@ -167,6 +167,7 @@ fun DeviceSettingsScreenHost(
        onOnePodModeChange = { vm.setOnePodMode(it) },
        onAutoPlayChange = { vm.setAutoPlay(it) },
        onAutoPauseChange = { vm.setAutoPause(it) },
+        onStartMusicOnWearChange = { vm.setStartMusicOnWear(it) },
        onAutoConnectChange = { vm.setAutoConnect(it) },
        onAutoConnectConditionChange = { vm.setAutoConnectCondition(it) },
        onShowPopUpOnCaseOpenChange = { vm.setShowPopUpOnCaseOpen(it) },
@@ -205,6 +206,7 @@ fun DeviceSettingsScreen(
    onOnePodModeChange: (Boolean) -> Unit = {},
    onAutoPlayChange: (Boolean) -> Unit = {},
    onAutoPauseChange: (Boolean) -> Unit = {},
+    onStartMusicOnWearChange: (Boolean) -> Unit = {},
    onAutoConnectChange: (Boolean) -> Unit = {},
    onAutoConnectConditionChange: (AutoConnectCondition) -> Unit = {},
    onShowPopUpOnCaseOpenChange: (Boolean) -> Unit = {},
@@ -342,6 +344,7 @@ fun DeviceSettingsScreen(
                        monitorMode = state.monitorMode,
                        onAutoPlayChange = onAutoPlayChange,
                        onAutoPauseChange = onAutoPauseChange,
+                        onStartMusicOnWearChange = onStartMusicOnWearChange,
                        onOnePodModeChange = onOnePodModeChange,
                        onConversationalAwarenessChange = onConversationalAwarenessChange,
                        onSleepDetectionChange = onSleepDetectionChange,
@@ -382,6 +382,15 @@ class DeviceSettingsViewModel @Inject constructor(
        syncEarDetection(autoPause = enabled)
    }

+    fun setStartMusicOnWear(enabled: Boolean) = launch {
+        log(TAG, INFO) { "setStartMusicOnWear($enabled)" }
+        if (enabled && !upgradeRepo.isPro()) {
+            navTo(Nav.Main.Upgrade)
+            return@launch
+        }
+        updateProfileNow { it.copy(startMusicOnWear = enabled) }
+    }
+
    /**
     * Keeps the device-side Automatic Ear Detection setting in sync with the
     * auto-play / auto-pause reaction toggles.  When either reaction is active
@@ -48,6 +48,7 @@ internal fun ReactionsCard(
    monitorMode: MonitorMode,
    onAutoPlayChange: (Boolean) -> Unit = {},
    onAutoPauseChange: (Boolean) -> Unit = {},
+    onStartMusicOnWearChange: (Boolean) -> Unit = {},
    onOnePodModeChange: (Boolean) -> Unit = {},
    onConversationalAwarenessChange: (Boolean) -> Unit = {},
    onSleepDetectionChange: (Boolean) -> Unit = {},
@@ -73,6 +74,16 @@ internal fun ReactionsCard(
                onCheckedChange = onAutoPlayChange,
                requiresUpgrade = !isPro,
            )
+            if (reactions.autoPlay) {
+                SettingsSwitchItem(
+                    icon = Icons.TwoTone.PlayCircle,
+                    title = stringResource(R.string.settings_start_music_on_wear_label),
+                    subtitle = stringResource(R.string.settings_start_music_on_wear_description),
+                    checked = reactions.startMusicOnWear,
+                    onCheckedChange = onStartMusicOnWearChange,
+                    requiresUpgrade = !isPro,
+                )
+            }
            SettingsSwitchItem(
                icon = Icons.TwoTone.PauseCircle,
                title = stringResource(R.string.settings_autopause_label),
@@ -25,6 +25,7 @@ data class AppleDeviceProfile(
    @SerialName("address") override val address: String? = null,
    @SerialName("reactionAutoPause") val autoPause: Boolean = false,
    @SerialName("reactionAutoPlay") val autoPlay: Boolean = false,
+    @SerialName("reactionStartMusicOnWear") val startMusicOnWear: Boolean = false,
    @SerialName("reactionOnePodMode") val onePodMode: Boolean = false,
    @SerialName("reactionAutoConnect") val autoConnect: Boolean = false,
    @SerialName("reactionAutoConnectCondition") val autoConnectCondition: AutoConnectCondition = AutoConnectCondition.WHEN_SEEN,
@@ -49,6 +50,7 @@ data class AppleDeviceProfile(
        get() = ReactionConfig(
            autoPause = autoPause,
            autoPlay = autoPlay,
+            startMusicOnWear = startMusicOnWear,
            onePodMode = onePodMode,
            autoConnect = autoConnect,
            autoConnectCondition = autoConnectCondition,
@@ -62,6 +64,7 @@ data class AppleDeviceProfile(
        "identityKey=${if (identityKey == null) "null" else "<redacted>"}, " +
        "encryptionKey=${if (encryptionKey == null) "null" else "<redacted>"}, " +
        "address=$address, autoPause=$autoPause, autoPlay=$autoPlay, " +
+        "startMusicOnWear=$startMusicOnWear, " +
        "onePodMode=$onePodMode, autoConnect=$autoConnect, " +
        "autoConnectCondition=$autoConnectCondition, " +
        "showPopUpOnCaseOpen=$showPopUpOnCaseOpen, " +
@@ -5,6 +5,7 @@ import eu.darken.capod.reaction.core.autoconnect.AutoConnectCondition
 data class ReactionConfig(
    val autoPause: Boolean = false,
    val autoPlay: Boolean = false,
+    val startMusicOnWear: Boolean = false,
    val onePodMode: Boolean = false,
    val autoConnect: Boolean = false,
    val autoConnectCondition: AutoConnectCondition = AutoConnectCondition.WHEN_SEEN,
@@ -169,7 +169,6 @@ class PlayPause @Inject constructor(

                val isCurrentlyPlaying = mediaControl.isPlaying
                val wasRecentlyPausedByUs = mediaControl.wasRecentlyPausedByCap
-                val wasMusicExternallyStoppedRecently = mediaControl.wasMusicExternallyStoppedRecently

                val source = current.earDetectionSource()

@@ -180,7 +179,7 @@ class PlayPause @Inject constructor(
                    onePodMode = reactions.onePodMode,
                    isCurrentlyPlaying = isCurrentlyPlaying,
                    wasRecentlyPausedByUs = wasRecentlyPausedByUs,
-                    wasMusicExternallyStoppedRecently = wasMusicExternallyStoppedRecently,
+                    startMusicOnWear = reactions.startMusicOnWear,
                )

                // BLE-only autoplay confirmation only applies to UNAUTHENTICATED sources.
@@ -206,7 +205,7 @@ class PlayPause @Inject constructor(
                    shouldStageBleOnlyPlay = shouldStageBleOnlyPlay,
                    isCurrentlyPlaying = isCurrentlyPlaying,
                    wasRecentlyPausedByUs = wasRecentlyPausedByUs,
-                    wasMusicExternallyStoppedRecently = wasMusicExternallyStoppedRecently,
+                    startMusicOnWear = reactions.startMusicOnWear,
                )
                pendingPlayConfirmation = confirmation.pending

@@ -291,11 +290,11 @@ class PlayPause @Inject constructor(
        onePodMode: Boolean,
        isCurrentlyPlaying: Boolean,
        wasRecentlyPausedByUs: Boolean = false,
-        wasMusicExternallyStoppedRecently: Boolean = false,
+        startMusicOnWear: Boolean = false,
    ): PlayPauseDecision = if (onePodMode) {
-        evaluateOnePodMode(previous, current, isCurrentlyPlaying, wasRecentlyPausedByUs, wasMusicExternallyStoppedRecently)
+        evaluateOnePodMode(previous, current, isCurrentlyPlaying, wasRecentlyPausedByUs, startMusicOnWear)
    } else {
-        evaluateNormalMode(previous, current, isCurrentlyPlaying, wasRecentlyPausedByUs, wasMusicExternallyStoppedRecently)
+        evaluateNormalMode(previous, current, isCurrentlyPlaying, wasRecentlyPausedByUs, startMusicOnWear)
    }

    private fun evaluateOnePodMode(
@@ -303,7 +302,7 @@ class PlayPause @Inject constructor(
        current: EarDetectionState,
        isCurrentlyPlaying: Boolean,
        wasRecentlyPausedByUs: Boolean,
-        wasMusicExternallyStoppedRecently: Boolean,
+        startMusicOnWear: Boolean,
    ): PlayPauseDecision {
        val netChange = current.podCount - previous.podCount

@@ -315,13 +314,12 @@ class PlayPause @Inject constructor(
                reason = "One-pod mode: pod(s) removed (net change: $netChange)"
            )

-            // Net increase: pod(s) inserted → play, but only when either we paused recently
-            // (resume our pause / handle the AudioManager.isMusicActive race) or there is no
-            // sign of a recent external stop (cold start). Suppress autoplay otherwise so
-            // CAP doesn't override a user-initiated pause.
+            // Net increase: pod(s) inserted → play, but only when we paused recently OR the user
+            // opted in to firing a play key on cold wear. Without an opt-in, suppress autoplay
+            // so we never override a user-initiated pause or fire over silence.
            netChange > 0 && (
                wasRecentlyPausedByUs ||
-                    (!isCurrentlyPlaying && !wasMusicExternallyStoppedRecently)
+                    (startMusicOnWear && !isCurrentlyPlaying)
                ) -> PlayPauseDecision(
                shouldPlay = true,
                shouldPause = false,
@@ -343,19 +341,18 @@ class PlayPause @Inject constructor(
        current: EarDetectionState,
        isCurrentlyPlaying: Boolean,
        wasRecentlyPausedByCap: Boolean,
-        wasMusicExternallyStoppedRecently: Boolean,
+        startMusicOnWear: Boolean,
    ): PlayPauseDecision {
        val wasWorn = previous.bothInEar
        val isWorn = current.bothInEar

        return when {
-            // Transition: not worn → worn → play, but only when either we paused recently
-            // (resume our pause / handle the AudioManager.isMusicActive race) or there is no
-            // sign of a recent external stop (cold start). Suppress autoplay otherwise so
-            // CAP doesn't override a user-initiated pause.
+            // Transition: not worn → worn → play, but only when we paused recently OR the user
+            // opted in to firing a play key on cold wear. Without an opt-in, suppress autoplay
+            // so we never override a user-initiated pause or fire over silence.
            !wasWorn && isWorn && (
                wasRecentlyPausedByCap ||
-                    (!isCurrentlyPlaying && !wasMusicExternallyStoppedRecently)
+                    (startMusicOnWear && !isCurrentlyPlaying)
                ) -> PlayPauseDecision(
                shouldPlay = true,
                shouldPause = false,
@@ -389,7 +386,7 @@ class PlayPause @Inject constructor(
        shouldStageBleOnlyPlay: Boolean,
        isCurrentlyPlaying: Boolean,
        wasRecentlyPausedByUs: Boolean,
-        wasMusicExternallyStoppedRecently: Boolean = false,
+        startMusicOnWear: Boolean = false,
    ): PlayConfirmationResult {
        val activePending = pending?.takeIf {
            it.profileId == profileId && it.onePodMode == onePodMode && autoPlayEnabled
@@ -399,7 +396,7 @@ class PlayPause @Inject constructor(
            currentState == activePending.targetState &&
            (
                wasRecentlyPausedByUs ||
-                    (!isCurrentlyPlaying && !wasMusicExternallyStoppedRecently)
+                    (startMusicOnWear && !isCurrentlyPlaying)
                )
        ) {
            return PlayConfirmationResult(
@@ -53,7 +53,9 @@
    <string name="settings_autopause_label">Auto pause</string>
    <string name="settings_autopause_description">Pause audio when removing the device from your ear.</string>
    <string name="settings_autopplay_label">Auto play</string>
-    <string name="settings_autoplay_description">Start audio playback when device is worn.</string>
+    <string name="settings_autoplay_description">Resume music when wearing your pods again, if Auto pause stopped it. Music you paused yourself stays paused.</string>
+    <string name="settings_start_music_on_wear_label">Start music on wear</string>
+    <string name="settings_start_music_on_wear_description">Always tries to play music when wearing your pods. May also restart music you paused yourself.</string>
    <string name="settings_eardetection_info_label">Ear detection note</string>
    <string name="settings_eardetection_info_description">If ear detection only works for one pod, this is an Apple limitation. Only the \"primary pod\" (used for microphone) is detected. Configure on Apple devices: Settings → Bluetooth → AirPods → Microphone.</string>
    <string name="settings_fake_data_label">Fake data</string>