Gate nearby notes behind tap-to-reveal consent (#771)

* Add nearby notes tap-to-reveal consent * Stop nearby notes while app is backgrounded
2026-08-08 06:46:11 +00:00 · 2026-07-27 02:17:44 +02:00 · 2026-07-27 02:17:44 +02:00 · d615fc9cc0
commit d615fc9cc0
parent 92d07b22fa
40 changed files with 678 additions and 72 deletions
--- a/app/src/main/java/com/bitchat/android/nostr/LocationNotesManager.kt
+++ b/app/src/main/java/com/bitchat/android/nostr/LocationNotesManager.kt
@ -13,7 +13,7 @@ import kotlinx.coroutines.flow.asStateFlow
 */
@MainThread
 class LocationNotesManager private constructor() {
-    
+
    companion object {
        private const val TAG = "LocationNotesManager"
        private const val MAX_NOTES_IN_MEMORY = 500
@ -27,7 +27,7 @@ class LocationNotesManager private constructor() {
            }
        }
    }
-    
+
    /**
     * Note data class matching iOS implementation
     */
@ -94,6 +94,8 @@ class LocationNotesManager private constructor() {
    
    // Coroutine scope for background operations
    private val scope = CoroutineScope(Dispatchers.Main + SupervisorJob())
+    private var subscribeRetryJob: Job? = null
+    private var initialLoadJob: Job? = null
    
    /**
     * Initialize dependencies
@ -289,6 +291,11 @@ class LocationNotesManager private constructor() {
     * Subscribe to location notes for current geohash
     */
    private fun subscribeAll() {
+        subscribeRetryJob?.cancel()
+        subscribeRetryJob = null
+        initialLoadJob?.cancel()
+        initialLoadJob = null
+
        val currentGeohash = _geohash.value
        if (currentGeohash == null) {
            Log.w(TAG, "Cannot subscribe - no geohash set")
@ -301,7 +308,7 @@ class LocationNotesManager private constructor() {
            Log.e(TAG, "Cannot subscribe - subscribe function not initialized; will retry shortly")
            _state.value = State.LOADING
            // Retry a few times in case initialization is racing the sheet open
-            scope.launch {
+            subscribeRetryJob = scope.launch {
                var attempts = 0
                while (attempts < 10 && subscribeFunc == null) {
                    delay(300)
@ -342,9 +349,9 @@ class LocationNotesManager private constructor() {
        }
        
        // Mark initial load complete after brief delay to allow relay responses
-        scope.launch {
+        initialLoadJob = scope.launch {
            delay(2000) // Wait 2 seconds for initial batch
-            if (!_initialLoadComplete.value!!) {
+            if (_geohash.value == currentGeohash && !_initialLoadComplete.value) {
                _initialLoadComplete.value = true
                _state.value = State.READY
                Log.d(TAG, "Initial load complete for geohash: $currentGeohash (${noteIDs.size} notes)")
@ -441,6 +448,11 @@ class LocationNotesManager private constructor() {
     * Cancel subscription and clear state
     */
    fun cancel() {
+        subscribeRetryJob?.cancel()
+        subscribeRetryJob = null
+        initialLoadJob?.cancel()
+        initialLoadJob = null
+
        if (subscriptionIDs.isNotEmpty()) {
            subscriptionIDs.values.forEach { subId ->
                try {
@ -453,17 +465,26 @@ class LocationNotesManager private constructor() {
        subscribedGeohashes = emptySet()
        _state.value = State.IDLE
    }
-    
+
    /**
-     * Cleanup resources
+     * End the nearby-notes session and discard location-correlated UI state.
+     * Unlike [cancel], this also clears the target so a later activation can
+     * safely subscribe to the same building geohash again.
     */
-    fun cleanup() {
+    fun stop() {
        cancel()
-        scope.cancel()
        _notes.value = emptyList()
        noteIDs.clear()
        _geohash.value = null
        _initialLoadComplete.value = false
        _errorMessage.value = null
    }
+
+    /**
+     * Cleanup resources
+     */
+    fun cleanup() {
+        stop()
+        scope.cancel()
+    }
 }
--- a/app/src/main/java/com/bitchat/android/nostr/NearbyNotesController.kt
+++ b/app/src/main/java/com/bitchat/android/nostr/NearbyNotesController.kt
@ -0,0 +1,130 @@
+package com.bitchat.android.nostr
+
+import androidx.annotation.MainThread
+import com.bitchat.android.geohash.GeohashChannel
+import com.bitchat.android.geohash.GeohashChannelLevel
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
+
+/**
+ * Session-scoped consent gate for nearby location notes.
+ *
+ * Merely rendering the mesh timeline must not open a building-precision Nostr
+ * subscription. A subscription is eligible only after an explicit reveal and
+ * while the app is foregrounded and at least one nearby-notes surface is active.
+ */
+@MainThread
+class NearbyNotesController internal constructor(
+    private val subscribe: (String) -> Unit,
+    private val unsubscribe: () -> Unit,
+) {
+    private val _revealed = MutableStateFlow(false)
+    val revealed: StateFlow<Boolean> = _revealed.asStateFlow()
+
+    private var activeHolders = 0
+    private var locationEnabled = false
+    private var locationAuthorized = false
+    private var appForeground = false
+    private var buildingGeohash: String? = null
+    private var subscribedGeohash: String? = null
+
+    /**
+     * Unlocks nearby notes for this process session. Deactivation deliberately
+     * does not reset consent, matching the iOS privacy model.
+     */
+    fun reveal() {
+        if (_revealed.value) return
+        _revealed.value = true
+        reconcileSubscription()
+    }
+
+    /** Holds the subscription while a nearby-notes surface is visible. */
+    fun activate() {
+        activeHolders += 1
+        reconcileSubscription()
+    }
+
+    /** Releases a matching [activate] hold and unsubscribes after the last one. */
+    fun deactivate() {
+        activeHolders = (activeHolders - 1).coerceAtLeast(0)
+        reconcileSubscription()
+    }
+
+    /** Closes the live subscription whenever the process leaves the foreground. */
+    fun updateAppForeground(isForeground: Boolean) {
+        appForeground = isForeground
+        reconcileSubscription()
+    }
+
+    /**
+     * Updates the privacy-sensitive inputs independently of view activation.
+     * Permission revocation, location disable, or loss of the building cell
+     * immediately closes any live subscription.
+     */
+    fun updateAvailability(
+        locationEnabled: Boolean,
+        locationAuthorized: Boolean,
+        buildingGeohash: String?,
+    ) {
+        this.locationEnabled = locationEnabled
+        this.locationAuthorized = locationAuthorized
+        this.buildingGeohash = buildingGeohash
+            ?.trim()
+            ?.lowercase()
+            ?.takeIf { it.isNotEmpty() }
+        reconcileSubscription()
+    }
+
+    fun offersRevealHint(): Boolean =
+        !_revealed.value &&
+            locationEnabled &&
+            locationAuthorized &&
+            buildingGeohash != null
+
+    private fun reconcileSubscription() {
+        val target = buildingGeohash.takeIf {
+            activeHolders > 0 &&
+                appForeground &&
+                _revealed.value &&
+                locationEnabled &&
+                locationAuthorized
+        }
+
+        if (subscribedGeohash != null && subscribedGeohash != target) {
+            unsubscribe()
+            subscribedGeohash = null
+        }
+
+        if (target != null && subscribedGeohash == null) {
+            subscribe(target)
+            subscribedGeohash = target
+        }
+    }
+
+    companion object {
+        val shared: NearbyNotesController by lazy {
+            val manager = LocationNotesManager.getInstance()
+            NearbyNotesController(
+                subscribe = manager::setGeohash,
+                unsubscribe = manager::stop,
+            )
+        }
+    }
+}
+
+/**
+ * Building precision is location-notes precision and remains private before a
+ * reveal. Explicit bookmarks remain eligible because saving one is itself an
+ * intentional location act.
+ */
+internal fun geohashesForSampling(
+    availableChannels: List<GeohashChannel>,
+    bookmarks: Collection<String>,
+    notesRevealed: Boolean,
+): List<String> = buildSet {
+    availableChannels
+        .filter { notesRevealed || it.level != GeohashChannelLevel.BUILDING }
+        .mapTo(this) { it.geohash }
+    addAll(bookmarks)
+}.toList()
--- a/app/src/main/java/com/bitchat/android/ui/ChatScreen.kt
+++ b/app/src/main/java/com/bitchat/android/ui/ChatScreen.kt
@ -12,19 +12,35 @@ import androidx.compose.runtime.*
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.Alignment
+import androidx.compose.ui.platform.LocalContext
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.ArrowDownward
 import androidx.compose.foundation.BorderStroke
 import androidx.compose.foundation.shape.CircleShape
 import androidx.compose.material3.IconButton
 import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.text.font.FontFamily
 import androidx.compose.ui.text.TextRange
 import androidx.compose.ui.text.input.TextFieldValue
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.Dp
+import androidx.compose.ui.unit.sp
+import androidx.compose.ui.semantics.contentDescription
+import androidx.compose.ui.semantics.semantics
+import androidx.compose.ui.semantics.clearAndSetSemantics
 import androidx.compose.ui.zIndex
+import androidx.lifecycle.DefaultLifecycleObserver
+import androidx.lifecycle.Lifecycle
+import androidx.lifecycle.LifecycleOwner
+import androidx.lifecycle.ProcessLifecycleOwner
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import com.bitchat.android.R
+import com.bitchat.android.geohash.ChannelID
+import com.bitchat.android.geohash.GeohashChannelLevel
+import com.bitchat.android.geohash.LocationChannelManager
 import com.bitchat.android.model.BitchatMessage
+import com.bitchat.android.nostr.LocationNotesManager
+import com.bitchat.android.nostr.NearbyNotesController
 import com.bitchat.android.ui.media.FullScreenImageViewer

 /**
@ -86,6 +102,67 @@ fun ChatScreen(viewModel: ChatViewModel) {

    // Get location channel info for timeline switching
    val selectedLocationChannel by viewModel.selectedLocationChannel.collectAsStateWithLifecycle()
+    val context = LocalContext.current
+    val locationManager = remember { LocationChannelManager.getInstance(context) }
+    val nearbyNotesController = remember { NearbyNotesController.shared }
+    val nearbyNotesRevealed by nearbyNotesController.revealed.collectAsStateWithLifecycle()
+    val locationPermissionState by locationManager.permissionState.collectAsStateWithLifecycle()
+    val locationEnabled by locationManager.effectiveLocationEnabled.collectAsStateWithLifecycle(false)
+    val availableLocationChannels by locationManager.availableChannels.collectAsStateWithLifecycle()
+    val nearbyNotes by remember { LocationNotesManager.getInstance() }
+        .notes
+        .collectAsStateWithLifecycle()
+    val buildingGeohash = availableLocationChannels
+        .firstOrNull { it.level == GeohashChannelLevel.BUILDING }
+        ?.geohash
+    val isMeshTimeline =
+        currentChannel == null &&
+            selectedLocationChannel is ChannelID.Mesh &&
+            selectedPrivatePeer == null &&
+            privateChatSheetPeer == null
+
+    val processLifecycleOwner = remember { ProcessLifecycleOwner.get() }
+    DisposableEffect(processLifecycleOwner, nearbyNotesController) {
+        val lifecycle = processLifecycleOwner.lifecycle
+        val observer = object : DefaultLifecycleObserver {
+            override fun onStart(owner: LifecycleOwner) {
+                nearbyNotesController.updateAppForeground(true)
+            }
+
+            override fun onStop(owner: LifecycleOwner) {
+                nearbyNotesController.updateAppForeground(false)
+            }
+        }
+
+        lifecycle.addObserver(observer)
+        nearbyNotesController.updateAppForeground(
+            lifecycle.currentState.isAtLeast(Lifecycle.State.STARTED),
+        )
+
+        onDispose {
+            lifecycle.removeObserver(observer)
+            nearbyNotesController.updateAppForeground(false)
+        }
+    }
+
+    DisposableEffect(
+        isMeshTimeline,
+        locationEnabled,
+        locationPermissionState,
+        buildingGeohash,
+        nearbyNotesController,
+    ) {
+        nearbyNotesController.updateAvailability(
+            locationEnabled = locationEnabled,
+            locationAuthorized =
+                locationPermissionState == LocationChannelManager.PermissionState.AUTHORIZED,
+            buildingGeohash = buildingGeohash,
+        )
+        if (isMeshTimeline) nearbyNotesController.activate()
+        onDispose {
+            if (isMeshTimeline) nearbyNotesController.deactivate()
+        }
+    }

    // Determine what messages to show based on current context (unified timelines)
    // Legacy private chat timeline removed - private chats now exclusively use PrivateChatSheet
@ -131,58 +208,91 @@ fun ChatScreen(viewModel: ChatViewModel) {
            )

            // Messages area - takes up available space, will compress when keyboard appears
-            MessagesList(
-                messages = displayMessages,
-                currentUserNickname = nickname,
-                meshService = viewModel.meshServiceFacade,
-                modifier = Modifier.weight(1f),
-                forceScrollToBottom = forceScrollToBottom,
-                onScrolledUpChanged = { isUp -> isScrolledUp = isUp },
-                onNicknameClick = { fullSenderName ->
-                    // Single click - mention user in text input
-                    val currentText = messageText.text
-                    
-                    // Extract base nickname and hash suffix from full sender name
-                    val (baseName, hashSuffix) = splitSuffix(fullSenderName)
-                    
-                    // Check if we're in a geohash channel to include hash suffix
-                    val selectedLocationChannel = viewModel.selectedLocationChannel.value
-                    val mentionText = if (selectedLocationChannel is com.bitchat.android.geohash.ChannelID.Location && hashSuffix.isNotEmpty()) {
-                        // In geohash chat - include the hash suffix from the full display name
-                        "@$baseName$hashSuffix"
-                    } else {
-                        // Regular chat - just the base nickname
-                        "@$baseName"
-                    }
-                    
-                    val newText = when {
-                        currentText.isEmpty() -> "$mentionText "
-                        currentText.endsWith(" ") -> "$currentText$mentionText "
-                        else -> "$currentText $mentionText "
-                    }
-                    
-                    messageText = TextFieldValue(
-                        text = newText,
-                        selection = TextRange(newText.length)
+            Column(modifier = Modifier.weight(1f)) {
+                if (isMeshTimeline && nearbyNotesRevealed && nearbyNotes.isNotEmpty()) {
+                    NearbyNotesStrip(
+                        noteCount = nearbyNotes.size,
+                        onClick = { showLocationNotesSheet = true },
                    )
-                },
-                onMessageLongPress = { message ->
-                    // Message long press - open user action sheet with message context
-                    // Extract base nickname from message sender (contains all necessary info)
-                    val (baseName, _) = splitSuffix(message.sender)
-                    selectedUserForSheet = baseName
-                    selectedMessageForSheet = message
-                    showUserSheet = true
-                },
-                onCancelTransfer = { msg ->
-                    viewModel.cancelMediaSend(msg.id)
-                },
-                onImageClick = { currentPath, allImagePaths, initialIndex ->
-                    viewerImagePaths = allImagePaths
-                    initialViewerIndex = initialIndex
-                    showFullScreenImageViewer = true
                }
-            )
+
+                Box(
+                    modifier = Modifier
+                        .weight(1f)
+                        .fillMaxWidth(),
+                ) {
+                    MessagesList(
+                        messages = displayMessages,
+                        currentUserNickname = nickname,
+                        meshService = viewModel.meshServiceFacade,
+                        modifier = Modifier.fillMaxSize(),
+                        forceScrollToBottom = forceScrollToBottom,
+                        onScrolledUpChanged = { isUp -> isScrolledUp = isUp },
+                        onNicknameClick = { fullSenderName ->
+                            // Single click - mention user in text input
+                            val currentText = messageText.text
+
+                            // Extract base nickname and hash suffix from full sender name
+                            val (baseName, hashSuffix) = splitSuffix(fullSenderName)
+
+                            // Check if we're in a geohash channel to include hash suffix
+                            val selectedLocationChannel = viewModel.selectedLocationChannel.value
+                            val mentionText = if (
+                                selectedLocationChannel is ChannelID.Location &&
+                                hashSuffix.isNotEmpty()
+                            ) {
+                                // In geohash chat - include the hash suffix from the full display name
+                                "@$baseName$hashSuffix"
+                            } else {
+                                // Regular chat - just the base nickname
+                                "@$baseName"
+                            }
+
+                            val newText = when {
+                                currentText.isEmpty() -> "$mentionText "
+                                currentText.endsWith(" ") -> "$currentText$mentionText "
+                                else -> "$currentText $mentionText "
+                            }
+
+                            messageText = TextFieldValue(
+                                text = newText,
+                                selection = TextRange(newText.length),
+                            )
+                        },
+                        onMessageLongPress = { message ->
+                            // Message long press - open user action sheet with message context
+                            // Extract base nickname from message sender (contains all necessary info)
+                            val (baseName, _) = splitSuffix(message.sender)
+                            selectedUserForSheet = baseName
+                            selectedMessageForSheet = message
+                            showUserSheet = true
+                        },
+                        onCancelTransfer = { msg ->
+                            viewModel.cancelMediaSend(msg.id)
+                        },
+                        onImageClick = { currentPath, allImagePaths, initialIndex ->
+                            viewerImagePaths = allImagePaths
+                            initialViewerIndex = initialIndex
+                            showFullScreenImageViewer = true
+                        },
+                    )
+
+                    if (
+                        displayMessages.isEmpty() &&
+                        isMeshTimeline &&
+                        !nearbyNotesRevealed &&
+                        locationEnabled &&
+                        locationPermissionState ==
+                            LocationChannelManager.PermissionState.AUTHORIZED &&
+                        buildingGeohash != null
+                    ) {
+                        NearbyNotesRevealHint(
+                            onClick = nearbyNotesController::reveal,
+                            modifier = Modifier.align(Alignment.Center),
+                        )
+                    }
+                }
+            }
            // Input area - stays at bottom
        // Bridge file share from lower-level input to ViewModel
    androidx.compose.runtime.LaunchedEffect(Unit) {
@ -253,7 +363,10 @@ fun ChatScreen(viewModel: ChatViewModel) {
            onShowAppInfo = { viewModel.showAppInfo() },
            onPanicClear = { viewModel.panicClearAllData() },
            onLocationChannelsClick = { showLocationChannelsSheet = true },
-            onLocationNotesClick = { showLocationNotesSheet = true }
+            onLocationNotesClick = {
+                nearbyNotesController.reveal()
+                showLocationNotesSheet = true
+            }
        )

        // Divider under header - positioned after status bar + header height
@ -374,6 +487,68 @@ fun ChatScreen(viewModel: ChatViewModel) {
    }
 }

+@Composable
+private fun NearbyNotesRevealHint(
+    onClick: () -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    val actionLabel = stringResource(R.string.nearby_notes_reveal)
+    TextButton(
+        onClick = onClick,
+        modifier = modifier
+            .fillMaxWidth()
+            .heightIn(min = 48.dp)
+            .padding(horizontal = 24.dp)
+            .semantics { contentDescription = actionLabel },
+    ) {
+        Text(
+            text = "📍 $actionLabel",
+            modifier = Modifier.clearAndSetSemantics { },
+            color = MaterialTheme.colorScheme.primary,
+            fontFamily = FontFamily.Monospace,
+            fontSize = 12.sp,
+        )
+    }
+}
+
+@Composable
+private fun NearbyNotesStrip(
+    noteCount: Int,
+    onClick: () -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    Surface(
+        onClick = onClick,
+        modifier = modifier.fillMaxWidth(),
+        color = MaterialTheme.colorScheme.surfaceVariant.copy(alpha = 0.45f),
+    ) {
+        Row(
+            modifier = Modifier
+                .fillMaxWidth()
+                .heightIn(min = 48.dp)
+                .padding(horizontal = 12.dp, vertical = 7.dp),
+            verticalAlignment = Alignment.CenterVertically,
+        ) {
+            Text(
+                text = "📍 " + if (noteCount == 1) {
+                    stringResource(R.string.nearby_notes_one)
+                } else {
+                    stringResource(R.string.nearby_notes_many, noteCount)
+                },
+                modifier = Modifier.weight(1f),
+                color = MaterialTheme.colorScheme.primary,
+                fontFamily = FontFamily.Monospace,
+                fontSize = 12.sp,
+            )
+            Text(
+                text = "›",
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+                fontSize = 18.sp,
+            )
+        }
+    }
+}
+
@Composable
 fun ChatInputSection(
    messageText: TextFieldValue,
--- a/app/src/main/java/com/bitchat/android/ui/LocationChannelsSheet.kt
+++ b/app/src/main/java/com/bitchat/android/ui/LocationChannelsSheet.kt
@ -34,6 +34,8 @@ import com.bitchat.android.geohash.GeohashChannel
 import com.bitchat.android.geohash.GeohashChannelLevel
 import com.bitchat.android.geohash.LocationChannelManager
 import com.bitchat.android.geohash.GeohashBookmarksStore
+import com.bitchat.android.nostr.NearbyNotesController
+import com.bitchat.android.nostr.geohashesForSampling
 import com.bitchat.android.ui.theme.BASE_FONT_SIZE
 import androidx.compose.ui.res.stringResource
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
@ -61,6 +63,7 @@ fun LocationChannelsSheet(
    // Observe location manager state
    val permissionState by locationManager.permissionState.collectAsStateWithLifecycle()
    val availableChannels by locationManager.availableChannels.collectAsStateWithLifecycle()
+    val notesRevealed by NearbyNotesController.shared.revealed.collectAsStateWithLifecycle()
    val selectedChannel by locationManager.selectedChannel.collectAsStateWithLifecycle()
    val locationNames by locationManager.locationNames.collectAsStateWithLifecycle()
    val appLocationEnabled by locationManager.locationServicesEnabled.collectAsStateWithLifecycle()
@ -534,9 +537,13 @@ fun LocationChannelsSheet(
    }

    // Sampling management: update sampling when channels/bookmarks change
-    LaunchedEffect(isPresented, availableChannels, bookmarks) {
+    LaunchedEffect(isPresented, availableChannels, bookmarks, notesRevealed) {
        if (isPresented) {
-            val geohashes = (availableChannels.map { it.geohash } + bookmarks).toSet().toList()
+            val geohashes = geohashesForSampling(
+                availableChannels = availableChannels,
+                bookmarks = bookmarks,
+                notesRevealed = notesRevealed,
+            )
            viewModel.beginGeohashSampling(geohashes)
        } else {
            viewModel.endGeohashSampling()
--- a/app/src/main/java/com/bitchat/android/ui/LocationNotesSheet.kt
+++ b/app/src/main/java/com/bitchat/android/ui/LocationNotesSheet.kt
@ -32,6 +32,7 @@ import com.bitchat.android.core.ui.component.sheet.BitchatSheetTitle
 import com.bitchat.android.geohash.GeohashChannelLevel
 import com.bitchat.android.geohash.LocationChannelManager
 import com.bitchat.android.nostr.LocationNotesManager
+import com.bitchat.android.nostr.NearbyNotesController
 import java.text.SimpleDateFormat
 import java.util.*
 import java.util.Calendar
@ -58,12 +59,15 @@ fun LocationNotesSheet(
    // Managers
    val notesManager = remember { LocationNotesManager.getInstance() }
    val locationManager = remember { LocationChannelManager.getInstance(context) }
+    val nearbyNotesController = remember { NearbyNotesController.shared }
    
    // State
    val notes by notesManager.notes.collectAsStateWithLifecycle()
    val state by notesManager.state.collectAsStateWithLifecycle(LocationNotesManager.State.IDLE)
    val errorMessage by notesManager.errorMessage.collectAsStateWithLifecycle()
    val initialLoadComplete by notesManager.initialLoadComplete.collectAsStateWithLifecycle(false)
+    val permissionState by locationManager.permissionState.collectAsStateWithLifecycle()
+    val locationEnabled by locationManager.effectiveLocationEnabled.collectAsStateWithLifecycle(false)
    
    // SIMPLIFIED: Get count directly from notes list (no separate counter needed)
    val count = notes.size
@ -94,15 +98,24 @@ fun LocationNotesSheet(
        locationManager.refreshChannels()
    }

-    // Effect to set geohash when sheet opens
-    LaunchedEffect(geohash) {
-        notesManager.setGeohash(geohash)
-    }
-    
-    // Cleanup when sheet closes
-    DisposableEffect(Unit) {
+    // Opening the notes sheet is an explicit reveal. The balanced hold lets
+    // the mesh timeline keep the shared subscription alive after dismissal.
+    DisposableEffect(
+        geohash,
+        locationEnabled,
+        permissionState,
+        nearbyNotesController,
+    ) {
+        nearbyNotesController.updateAvailability(
+            locationEnabled = locationEnabled,
+            locationAuthorized =
+                permissionState == LocationChannelManager.PermissionState.AUTHORIZED,
+            buildingGeohash = geohash,
+        )
+        nearbyNotesController.activate()
+        nearbyNotesController.reveal()
        onDispose {
-            notesManager.cancel()
+            nearbyNotesController.deactivate()
        }
    }

--- a/app/src/main/res/values-ar/strings.xml
+++ b/app/src/main/res/values-ar/strings.xml
@ -401,4 +401,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">فتح قسم حول</string>
+  <string name="nearby_notes_reveal">تحقّق من الملاحظات المتروكة هنا</string>
+  <string name="nearby_notes_one">تُركت ملاحظة واحدة هنا — انقر للقراءة</string>
+  <string name="nearby_notes_many">تُركت %d ملاحظات هنا — انقر للقراءة</string>
 </resources>
--- a/app/src/main/res/values-bn/strings.xml
+++ b/app/src/main/res/values-bn/strings.xml
@ -388,4 +388,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">পরিচিতি খুলুন</string>
+  <string name="nearby_notes_reveal">এখানে রাখা নোট আছে কি না দেখুন</string>
+  <string name="nearby_notes_one">এখানে 1টি নোট রাখা আছে — পড়তে ট্যাপ করুন</string>
+  <string name="nearby_notes_many">এখানে %dটি নোট রাখা আছে — পড়তে ট্যাপ করুন</string>
 </resources>
--- a/app/src/main/res/values-de/strings.xml
+++ b/app/src/main/res/values-de/strings.xml
@ -402,4 +402,7 @@
  <string name="verify_success_body">Du hast %1$s verifiziert</string>
  <string name="verify_success_system_message">verifiziert %1$s</string>
    <string name="cd_open_about">Info öffnen</string>
+  <string name="nearby_notes_reveal">nachsehen, ob hier notizen hinterlassen wurden</string>
+  <string name="nearby_notes_one">1 notiz hier hinterlassen — tippen zum lesen</string>
+  <string name="nearby_notes_many">%d notizen hier hinterlassen — tippen zum lesen</string>
 </resources>
--- a/app/src/main/res/values-es/strings.xml
+++ b/app/src/main/res/values-es/strings.xml
@ -401,4 +401,7 @@
  <string name="verify_success_body">Verificaste a %1$s</string>
  <string name="verify_success_system_message">verificado %1$s</string>
    <string name="cd_open_about">Abrir Acerca de</string>
+  <string name="nearby_notes_reveal">buscar notas dejadas aquí</string>
+  <string name="nearby_notes_one">1 nota dejada aquí — toca para leer</string>
+  <string name="nearby_notes_many">%d notas dejadas aquí — toca para leer</string>
 </resources>
--- a/app/src/main/res/values-fa/strings.xml
+++ b/app/src/main/res/values-fa/strings.xml
@ -388,4 +388,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">باز کردن درباره</string>
+  <string name="nearby_notes_reveal">یادداشت‌های باقی‌مانده در اینجا را بررسی کنید</string>
+  <string name="nearby_notes_one">۱ یادداشت اینجا باقی مانده — برای خواندن ضربه بزنید</string>
+  <string name="nearby_notes_many">%d یادداشت اینجا باقی مانده — برای خواندن ضربه بزنید</string>
 </resources>
--- a/app/src/main/res/values-fil/strings.xml
+++ b/app/src/main/res/values-fil/strings.xml
@ -400,4 +400,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">Buksan ang Tungkol</string>
+  <string name="nearby_notes_reveal">tingnan kung may mga note na naiwan dito</string>
+  <string name="nearby_notes_one">1 note ang naiwan dito — i-tap para basahin</string>
+  <string name="nearby_notes_many">%d note ang naiwan dito — i-tap para basahin</string>
 </resources>
--- a/app/src/main/res/values-fr/strings.xml
+++ b/app/src/main/res/values-fr/strings.xml
@ -414,4 +414,7 @@
  <string name="verify_success_body">Vous avez vérifié %1$s</string>
  <string name="verify_success_system_message">vérifié %1$s</string>
    <string name="cd_open_about">Ouvrir À propos</string>
+  <string name="nearby_notes_reveal">vérifier s\'il y a des notes laissées ici</string>
+  <string name="nearby_notes_one">1 note laissée ici — appuyez pour lire</string>
+  <string name="nearby_notes_many">%d notes laissées ici — appuyez pour lire</string>
 </resources>
--- a/app/src/main/res/values-he/strings.xml
+++ b/app/src/main/res/values-he/strings.xml
@ -54,4 +54,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">פתיחת אודות</string>
+  <string name="nearby_notes_reveal">בדיקה אם הושארו כאן פתקים</string>
+  <string name="nearby_notes_one">פתק אחד הושאר כאן — הקש לקריאה</string>
+  <string name="nearby_notes_many">%d פתקים הושארו כאן — הקש לקריאה</string>
 </resources>
--- a/app/src/main/res/values-hi/strings.xml
+++ b/app/src/main/res/values-hi/strings.xml
@ -401,4 +401,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">परिचय खोलें</string>
+  <string name="nearby_notes_reveal">देखें कि यहाँ नोट छोड़े गए हैं या नहीं</string>
+  <string name="nearby_notes_one">यहाँ 1 नोट छोड़ा गया है — पढ़ने के लिए टैप करें</string>
+  <string name="nearby_notes_many">यहाँ %d नोट छोड़े गए हैं — पढ़ने के लिए टैप करें</string>
 </resources>
--- a/app/src/main/res/values-id/strings.xml
+++ b/app/src/main/res/values-id/strings.xml
@ -401,4 +401,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">Buka Tentang</string>
+  <string name="nearby_notes_reveal">periksa catatan yang ditinggalkan di sini</string>
+  <string name="nearby_notes_one">1 catatan ditinggalkan di sini — ketuk untuk membaca</string>
+  <string name="nearby_notes_many">%d catatan ditinggalkan di sini — ketuk untuk membaca</string>
 </resources>
--- a/app/src/main/res/values-it/strings.xml
+++ b/app/src/main/res/values-it/strings.xml
@ -434,4 +434,7 @@
  <string name="verify_success_body">Hai verificato %1$s</string>
  <string name="verify_success_system_message">verificato %1$s</string>
    <string name="cd_open_about">Apri Informazioni</string>
+  <string name="nearby_notes_reveal">controlla se ci sono note lasciate qui</string>
+  <string name="nearby_notes_one">1 nota lasciata qui — tocca per leggere</string>
+  <string name="nearby_notes_many">%d note lasciate qui — tocca per leggere</string>
 </resources>
--- a/app/src/main/res/values-ja/strings.xml
+++ b/app/src/main/res/values-ja/strings.xml
@ -401,4 +401,7 @@
  <string name="verify_success_body">%1$s を検証しました</string>
  <string name="verify_success_system_message">%1$s を検証しました</string>
    <string name="cd_open_about">このアプリについてを開く</string>
+  <string name="nearby_notes_reveal">ここに残されたメモを確認</string>
+  <string name="nearby_notes_one">ここに1件のメモがあります — タップして読む</string>
+  <string name="nearby_notes_many">ここに%d件のメモがあります — タップして読む</string>
 </resources>
--- a/app/src/main/res/values-ka/strings.xml
+++ b/app/src/main/res/values-ka/strings.xml
@ -388,4 +388,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">აპის შესახებ გახსნა</string>
+  <string name="nearby_notes_reveal">აქ დატოვებული ჩანაწერების შემოწმება</string>
+  <string name="nearby_notes_one">აქ 1 ჩანაწერია დატოვებული — წასაკითხად შეეხეთ</string>
+  <string name="nearby_notes_many">აქ %d ჩანაწერია დატოვებული — წასაკითხად შეეხეთ</string>
 </resources>
--- a/app/src/main/res/values-ko/strings.xml
+++ b/app/src/main/res/values-ko/strings.xml
@ -401,4 +401,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">정보 열기</string>
+  <string name="nearby_notes_reveal">여기 남겨진 쪽지 확인</string>
+  <string name="nearby_notes_one">여기 남겨진 쪽지 1개 — 탭하여 읽기</string>
+  <string name="nearby_notes_many">여기 남겨진 쪽지 %d개 — 탭하여 읽기</string>
 </resources>
--- a/app/src/main/res/values-mg/strings.xml
+++ b/app/src/main/res/values-mg/strings.xml
@ -414,4 +414,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">Sokafy ny momba</string>
+  <string name="nearby_notes_reveal">hizaha raha misy naoty navela teto</string>
+  <string name="nearby_notes_one">naoty 1 no navela teto — tsindrio raha hamaky</string>
+  <string name="nearby_notes_many">naoty %d no navela teto — tsindrio raha hamaky</string>
 </resources>
--- a/app/src/main/res/values-ms/strings.xml
+++ b/app/src/main/res/values-ms/strings.xml
@ -41,4 +41,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">Buka Perihal</string>
+  <string name="nearby_notes_reveal">semak nota yang ditinggalkan di sini</string>
+  <string name="nearby_notes_one">1 nota ditinggalkan di sini — ketik untuk baca</string>
+  <string name="nearby_notes_many">%d nota ditinggalkan di sini — ketik untuk baca</string>
 </resources>
--- a/app/src/main/res/values-ne/strings.xml
+++ b/app/src/main/res/values-ne/strings.xml
@ -400,4 +400,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">परिचय खोल्नुहोस्</string>
+  <string name="nearby_notes_reveal">यहाँ छोडिएका नोटहरू छन् कि हेर्नुहोस्</string>
+  <string name="nearby_notes_one">यहाँ 1 नोट छोडिएको छ — पढ्न ट्याप गर्नुहोस्</string>
+  <string name="nearby_notes_many">यहाँ %d नोटहरू छोडिएका छन् — पढ्न ट्याप गर्नुहोस्</string>
 </resources>
--- a/app/src/main/res/values-nl/strings.xml
+++ b/app/src/main/res/values-nl/strings.xml
@ -432,4 +432,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">Info openen</string>
+  <string name="nearby_notes_reveal">kijk of hier notities zijn achtergelaten</string>
+  <string name="nearby_notes_one">1 notitie hier achtergelaten — tik om te lezen</string>
+  <string name="nearby_notes_many">%d notities hier achtergelaten — tik om te lezen</string>
 </resources>
--- a/app/src/main/res/values-pa-rPK/strings.xml
+++ b/app/src/main/res/values-pa-rPK/strings.xml
@ -388,4 +388,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">ایپ بارے کھولو</string>
+  <string name="nearby_notes_reveal">ایتھے چھڈے نوٹس ویکھو</string>
+  <string name="nearby_notes_one">ایتھے 1 نوٹ چھڈیا گیا — پڑھݨ لئی ٹیپ کرو</string>
+  <string name="nearby_notes_many">ایتھے %d نوٹس چھڈے گئے — پڑھݨ لئی ٹیپ کرو</string>
 </resources>
--- a/app/src/main/res/values-pl/strings.xml
+++ b/app/src/main/res/values-pl/strings.xml
@ -54,4 +54,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">Otwórz informacje</string>
+  <string name="nearby_notes_reveal">sprawdź, czy zostawiono tutaj notatki</string>
+  <string name="nearby_notes_one">1 notatka zostawiona tutaj — stuknij, aby przeczytać</string>
+  <string name="nearby_notes_many">%d notatek zostawionych tutaj — stuknij, aby przeczytać</string>
 </resources>
--- a/app/src/main/res/values-pt-rBR/strings.xml
+++ b/app/src/main/res/values-pt-rBR/strings.xml
@ -400,4 +400,7 @@
  <string name="verify_success_title">Verificado</string>
  <string name="verify_success_body">Você verificou %1$s</string>
  <string name="verify_success_system_message">verificou %1$s</string>
+  <string name="nearby_notes_reveal">ver se há notas deixadas aqui</string>
+  <string name="nearby_notes_one">1 nota deixada aqui — toque para ler</string>
+  <string name="nearby_notes_many">%d notas deixadas aqui — toque para ler</string>
 </resources>
--- a/app/src/main/res/values-pt/strings.xml
+++ b/app/src/main/res/values-pt/strings.xml
@ -401,4 +401,7 @@
  <string name="verify_success_body">Você verificou %1$s</string>
  <string name="verify_success_system_message">verificou %1$s</string>
    <string name="cd_open_about">Abrir Sobre</string>
+  <string name="nearby_notes_reveal">ver se há notas deixadas aqui</string>
+  <string name="nearby_notes_one">1 nota deixada aqui — toque para ler</string>
+  <string name="nearby_notes_many">%d notas deixadas aqui — toque para ler</string>
 </resources>
--- a/app/src/main/res/values-ru/strings.xml
+++ b/app/src/main/res/values-ru/strings.xml
@ -390,4 +390,7 @@
  <string name="verify_success_body">Вы проверили %1$s</string>
  <string name="verify_success_system_message">проверен %1$s</string>
    <string name="cd_open_about">Открыть раздел «О приложении»</string>
+  <string name="nearby_notes_reveal">проверить, есть ли здесь заметки</string>
+  <string name="nearby_notes_one">здесь оставлена 1 заметка — нажмите, чтобы прочитать</string>
+  <string name="nearby_notes_many">здесь оставлено заметок: %d — нажмите, чтобы прочитать</string>
 </resources>
--- a/app/src/main/res/values-sv/strings.xml
+++ b/app/src/main/res/values-sv/strings.xml
@ -388,4 +388,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">Öppna Om</string>
+  <string name="nearby_notes_reveal">kolla om anteckningar lämnats här</string>
+  <string name="nearby_notes_one">1 anteckning lämnad här — tryck för att läsa</string>
+  <string name="nearby_notes_many">%d anteckningar lämnade här — tryck för att läsa</string>
 </resources>
--- a/app/src/main/res/values-ta/strings.xml
+++ b/app/src/main/res/values-ta/strings.xml
@ -41,4 +41,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">அறிமுகத்தைத் திற</string>
+  <string name="nearby_notes_reveal">இங்கே விடப்பட்ட குறிப்புகள் உள்ளதா எனப் பார்க்கவும்</string>
+  <string name="nearby_notes_one">இங்கே 1 குறிப்பு விடப்பட்டுள்ளது — படிக்க தட்டவும்</string>
+  <string name="nearby_notes_many">இங்கே %d குறிப்புகள் விடப்பட்டுள்ளன — படிக்க தட்டவும்</string>
 </resources>
--- a/app/src/main/res/values-th/strings.xml
+++ b/app/src/main/res/values-th/strings.xml
@ -388,4 +388,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">เปิดเกี่ยวกับ</string>
+  <string name="nearby_notes_reveal">ดูว่ามีโน้ตทิ้งไว้ที่นี่หรือไม่</string>
+  <string name="nearby_notes_one">มี 1 โน้ตทิ้งไว้ที่นี่ — แตะเพื่ออ่าน</string>
+  <string name="nearby_notes_many">มี %d โน้ตทิ้งไว้ที่นี่ — แตะเพื่ออ่าน</string>
 </resources>
--- a/app/src/main/res/values-tr/strings.xml
+++ b/app/src/main/res/values-tr/strings.xml
@ -388,4 +388,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">Hakkında’yı aç</string>
+  <string name="nearby_notes_reveal">buraya bırakılan notlara bak</string>
+  <string name="nearby_notes_one">buraya 1 not bırakıldı — okumak için dokun</string>
+  <string name="nearby_notes_many">buraya %d not bırakıldı — okumak için dokun</string>
 </resources>
--- a/app/src/main/res/values-uk/strings.xml
+++ b/app/src/main/res/values-uk/strings.xml
@ -41,4 +41,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">Відкрити розділ «Про застосунок»</string>
+  <string name="nearby_notes_reveal">перевірити, чи залишено тут нотатки</string>
+  <string name="nearby_notes_one">тут залишено 1 нотатку — торкніться, щоб прочитати</string>
+  <string name="nearby_notes_many">тут залишено %d нотаток — торкніться, щоб прочитати</string>
 </resources>
--- a/app/src/main/res/values-ur/strings.xml
+++ b/app/src/main/res/values-ur/strings.xml
@ -401,4 +401,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">تعارف کھولیں</string>
+  <string name="nearby_notes_reveal">دیکھیں کہ یہاں نوٹ چھوڑے گئے ہیں یا نہیں</string>
+  <string name="nearby_notes_one">یہاں 1 نوٹ چھوڑا گیا ہے — پڑھنے کے لیے تھپتھپائیں</string>
+  <string name="nearby_notes_many">یہاں %d نوٹ چھوڑے گئے ہیں — پڑھنے کے لیے تھپتھپائیں</string>
 </resources>
--- a/app/src/main/res/values-vi/strings.xml
+++ b/app/src/main/res/values-vi/strings.xml
@ -388,4 +388,7 @@
  <string name="verify_success_body">You verified %1$s</string>
  <string name="verify_success_system_message">verified %1$s</string>
    <string name="cd_open_about">Mở phần Giới thiệu</string>
+  <string name="nearby_notes_reveal">kiểm tra ghi chú để lại ở đây</string>
+  <string name="nearby_notes_one">có 1 ghi chú để lại ở đây — chạm để đọc</string>
+  <string name="nearby_notes_many">có %d ghi chú để lại ở đây — chạm để đọc</string>
 </resources>
--- a/app/src/main/res/values-zh-rCN/strings.xml
+++ b/app/src/main/res/values-zh-rCN/strings.xml
@ -53,5 +53,7 @@
  <string name="verify_success_title">已验证</string>
  <string name="verify_success_body">你已验证 %1$s</string>
  <string name="verify_success_system_message">已验证 %1$s</string>
+  <string name="nearby_notes_reveal">查看这里留下的留言</string>
+  <string name="nearby_notes_one">这里留有 1 条留言 — 点按阅读</string>
+  <string name="nearby_notes_many">这里留有 %d 条留言 — 点按阅读</string>
 </resources>
-
--- a/app/src/main/res/values-zh-rTW/strings.xml
+++ b/app/src/main/res/values-zh-rTW/strings.xml
@ -53,5 +53,7 @@
  <string name="verify_success_title">已验证</string>
  <string name="verify_success_body">你已验证 %1$s</string>
  <string name="verify_success_system_message">已验证 %1$s</string>
+  <string name="nearby_notes_reveal">查看這裡留下的留言</string>
+  <string name="nearby_notes_one">這裡留有 1 則留言 — 點按閱讀</string>
+  <string name="nearby_notes_many">這裡留有 %d 則留言 — 點按閱讀</string>
 </resources>
-
--- a/app/src/main/res/values-zh/strings.xml
+++ b/app/src/main/res/values-zh/strings.xml
@ -413,4 +413,7 @@
  <string name="verify_success_body">你已验证 %1$s</string>
  <string name="verify_success_system_message">已验证 %1$s</string>
    <string name="cd_open_about">打开“关于”</string>
+  <string name="nearby_notes_reveal">查看这里留下的留言</string>
+  <string name="nearby_notes_one">这里留有 1 条留言 — 点按阅读</string>
+  <string name="nearby_notes_many">这里留有 %d 条留言 — 点按阅读</string>
 </resources>
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@ -234,6 +234,10 @@
  <string name="location_level_region">region</string>

  <!-- Location notes sheet -->
+  <string name="nearby_notes_reveal">check for notes left here</string>
+  <string name="nearby_notes_one">1 note left here — tap to read</string>
+  <!-- Explicit one/many copy mirrors iOS across locales without CLDR quantity gaps. -->
+  <string name="nearby_notes_many" tools:ignore="PluralsCandidate">%d notes left here — tap to read</string>
  <plurals name="location_notes_title">
    <item quantity="one">#%1$s ± 1 • %2$d note</item>
    <item quantity="other">#%1$s ± 1 • %2$d notes</item>
--- a/app/src/test/kotlin/com/bitchat/android/nostr/NearbyNotesControllerTest.kt
+++ b/app/src/test/kotlin/com/bitchat/android/nostr/NearbyNotesControllerTest.kt
@ -0,0 +1,159 @@
+package com.bitchat.android.nostr
+
+import com.bitchat.android.geohash.GeohashChannel
+import com.bitchat.android.geohash.GeohashChannelLevel
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertTrue
+import org.junit.Test
+
+class NearbyNotesControllerTest {
+    private val subscriptions = mutableListOf<String>()
+    private var unsubscribeCount = 0
+
+    private fun controller() = NearbyNotesController(
+        subscribe = subscriptions::add,
+        unsubscribe = { unsubscribeCount += 1 },
+    )
+
+    private fun foregroundController() = controller().also {
+        it.updateAppForeground(true)
+    }
+
+    @Test
+    fun `active mesh timeline does not subscribe before explicit reveal`() {
+        val controller = foregroundController()
+
+        controller.updateAvailability(
+            locationEnabled = true,
+            locationAuthorized = true,
+            buildingGeohash = "u4pruydq",
+        )
+        controller.activate()
+
+        assertTrue(controller.offersRevealHint())
+        assertTrue(subscriptions.isEmpty())
+
+        controller.reveal()
+
+        assertFalse(controller.offersRevealHint())
+        assertEquals(listOf("u4pruydq"), subscriptions)
+    }
+
+    @Test
+    fun `reveal remains dormant until a nearby notes surface is active`() {
+        val controller = foregroundController()
+        controller.updateAvailability(true, true, "u4pruydq")
+
+        controller.reveal()
+
+        assertTrue(subscriptions.isEmpty())
+
+        controller.activate()
+
+        assertEquals(listOf("u4pruydq"), subscriptions)
+    }
+
+    @Test
+    fun `last deactivate unsubscribes exactly once`() {
+        val controller = foregroundController()
+        controller.updateAvailability(true, true, "u4pruydq")
+        controller.reveal()
+        controller.activate()
+        controller.activate()
+
+        controller.deactivate()
+        assertEquals(0, unsubscribeCount)
+
+        controller.deactivate()
+        controller.deactivate()
+
+        assertEquals(1, unsubscribeCount)
+    }
+
+    @Test
+    fun `backgrounding closes the subscription and foregrounding restores it`() {
+        val controller = foregroundController()
+        controller.updateAvailability(true, true, "u4pruydq")
+        controller.activate()
+        controller.reveal()
+
+        controller.updateAppForeground(false)
+
+        assertEquals(1, unsubscribeCount)
+        assertTrue(controller.revealed.value)
+
+        controller.updateAppForeground(false)
+        assertEquals(1, unsubscribeCount)
+
+        controller.updateAppForeground(true)
+        assertEquals(listOf("u4pruydq", "u4pruydq"), subscriptions)
+    }
+
+    @Test
+    fun `disable and permission revocation close the live subscription`() {
+        val controller = foregroundController()
+        controller.updateAvailability(true, true, "u4pruydq")
+        controller.activate()
+        controller.reveal()
+
+        controller.updateAvailability(false, true, "u4pruydq")
+        assertEquals(1, unsubscribeCount)
+
+        controller.updateAvailability(true, true, "u4pruydq")
+        assertEquals(listOf("u4pruydq", "u4pruydq"), subscriptions)
+
+        controller.updateAvailability(true, false, "u4pruydq")
+        assertEquals(2, unsubscribeCount)
+    }
+
+    @Test
+    fun `moving building cells releases old subscription before retargeting`() {
+        val events = mutableListOf<String>()
+        val controller = NearbyNotesController(
+            subscribe = { events += "subscribe:$it" },
+            unsubscribe = { events += "unsubscribe" },
+        )
+        controller.updateAppForeground(true)
+        controller.updateAvailability(true, true, "u4pruydq")
+        controller.activate()
+        controller.reveal()
+
+        controller.updateAvailability(true, true, "u4pruydr")
+
+        assertEquals(
+            listOf(
+                "subscribe:u4pruydq",
+                "unsubscribe",
+                "subscribe:u4pruydr",
+            ),
+            events,
+        )
+    }
+
+    @Test
+    fun `building sampling is excluded until reveal while bookmarks remain eligible`() {
+        val channels = listOf(
+            GeohashChannel(GeohashChannelLevel.BUILDING, "u4pruydq"),
+            GeohashChannel(GeohashChannelLevel.BLOCK, "u4pruyd"),
+            GeohashChannel(GeohashChannelLevel.CITY, "u4pru"),
+        )
+
+        assertEquals(
+            listOf("u4pruyd", "u4pru", "saved123"),
+            geohashesForSampling(
+                availableChannels = channels,
+                bookmarks = listOf("saved123"),
+                notesRevealed = false,
+            ),
+        )
+        assertEquals(
+            listOf("u4pruydq", "u4pruyd", "u4pru", "saved123"),
+            geohashesForSampling(
+                availableChannels = channels,
+                bookmarks = listOf("saved123"),
+                notesRevealed = true,
+            ),
+        )
+    }
+}