refactor: configure favorite-app bottom-bar tabs from the settings page

Reworks how favorites get into the bottom bar, per review: instead of a
grid Pin/Unpin that auto-appended to the bar, favorites are now activated
as a dedicated "Favorite apps" section in the bottom-bar settings page —
kept separate from the built-in destinations because favorites are dynamic
data, not the fixed NavBarItem enum.

- UiSettings/UiSettingsFlow/UISharedPreferences gain bottomBarFavoriteIds
  (a device-local list of FavoriteApp ids), persisted alongside the
  existing bottomBarItems.
- BottomBarSettingsScreen gets a "Favorite apps" section: one toggle per
  favorite to activate/deactivate it as a bottom-bar tab.
- AppBottomBar renders the favorite tabs from that settings list instead of
  a registry-side pinned set.
- FavoriteAppsRegistry drops the pinned-set machinery; the grid drops its
  Pin/Unpin item. The "All apps" grid remains a built-in destination.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MgMpRcWj6y82LxLiwcuzmN

amethyst/src/main/java/com/vitorpamplona/amethyst/favorites/FavoriteAppsRegistry.kt

@@ -22,7 +22,6 @@ package com.vitorpamplona.amethyst.favorites
 
 import android.content.Context
 import android.util.Log
-import androidx.datastore.preferences.core.Preferences
 import androidx.datastore.preferences.core.edit
 import androidx.datastore.preferences.core.stringPreferencesKey
 import androidx.datastore.preferences.preferencesDataStore
@@ -53,37 +52,24 @@ private val Context.favoriteAppsDataStore by preferencesDataStore(name = "favori
  */
 object FavoriteAppsRegistry {
     private val KEY = stringPreferencesKey("favorites")
-    private val PINNED_KEY = stringPreferencesKey("pinned")
 
     private val _favorites = MutableStateFlow<List<FavoriteApp>>(emptyList())
     val favorites: StateFlow<List<FavoriteApp>> = _favorites.asStateFlow()
 
-    // Ordered ids of favorites the user pinned as bottom-bar tabs. Only embeddable favorites
-    // (currently WebUrl) are ever pinned, so a pinned tab always swaps in place — never launches an
-    // activity from the bottom row.
-    private val _pinnedIds = MutableStateFlow<List<String>>(emptyList())
-    val pinnedIds: StateFlow<List<String>> = _pinnedIds.asStateFlow()
-
     private val scope = CoroutineScope(SupervisorJob() + Dispatchers.IO)
 
     @Volatile private var appContext: Context? = null
 
-    /** Binds the app context and hydrates the on-disk lists into [favorites] / [pinnedIds]. Idempotent. */
+    /** Binds the app context and hydrates the on-disk list into [favorites]. Idempotent. */
     fun init(context: Context) {
         if (appContext != null) return
         val ctx = context.applicationContext
         appContext = ctx
         scope.launch {
-            val prefs = ctx.favoriteAppsDataStore.data.first()
-            prefs[KEY]?.let { json ->
-                val loaded = decode(json)
-                // Don't clobber adds made in this session before hydration finished.
-                update { current -> (loaded + current).distinctBy { it.id } }
-            }
-            prefs[PINNED_KEY]?.let { json ->
-                val loaded = decodeIds(json)
-                updatePinned { current -> (loaded + current).distinct() }
-            }
+            val json = ctx.favoriteAppsDataStore.data.first()[KEY] ?: return@launch
+            val loaded = decode(json)
+            // Don't clobber adds made in this session before hydration finished.
+            update { current -> (loaded + current).distinctBy { it.id } }
         }
     }
 
@@ -92,46 +78,22 @@ object FavoriteAppsRegistry {
     /** Adds [app] to the end if not already present (by [FavoriteApp.id]). */
     fun add(app: FavoriteApp) = update { current -> if (current.any { it.id == app.id }) current else current + app }
 
-    fun remove(id: String) {
-        update { current -> current.filterNot { it.id == id } }
-        // A removed favorite can't stay pinned to the bottom bar.
-        setPinned(id, false)
-    }
+    fun remove(id: String) = update { current -> current.filterNot { it.id == id } }
 
     /** Replaces the whole list, e.g. after a drag-reorder. */
     fun setOrder(newOrder: List<FavoriteApp>) = update { newOrder }
 
-    fun isPinned(id: String): Boolean = _pinnedIds.value.contains(id)
-
-    /** Pins or unpins [id] as a bottom-bar tab (appended in pin order). */
-    fun setPinned(
-        id: String,
-        pinned: Boolean,
-    ) = updatePinned { current ->
-        if (pinned) (current + id).distinct() else current - id
-    }
-
     private inline fun update(transform: (List<FavoriteApp>) -> List<FavoriteApp>) {
         val next = transform(_favorites.value)
         if (next == _favorites.value) return
         _favorites.value = next
-        persist(KEY, encode(next))
+        persist(encode(next))
     }
 
-    private inline fun updatePinned(transform: (List<String>) -> List<String>) {
-        val next = transform(_pinnedIds.value)
-        if (next == _pinnedIds.value) return
-        _pinnedIds.value = next
-        persist(PINNED_KEY, JsonMapper.toJson(next))
-    }
-
-    private fun persist(
-        key: Preferences.Key<String>,
-        json: String,
-    ) {
+    private fun persist(json: String) {
         val ctx = appContext ?: return
         scope.launch {
-            ctx.favoriteAppsDataStore.edit { it[key] = json }
+            ctx.favoriteAppsDataStore.edit { it[KEY] = json }
         }
     }
 
@@ -171,14 +133,6 @@ object FavoriteAppsRegistry {
             emptyList()
         }
 
-    private fun decodeIds(json: String): List<String> =
-        try {
-            JsonMapper.fromJson<List<String>>(json)
-        } catch (e: Exception) {
-            Log.w("FavoriteAppsRegistry", "Failed to decode pinned favorites", e)
-            emptyList()
-        }
-
     private const val TYPE_NOSTR = "nostr"
     private const val TYPE_URL = "url"
 }

amethyst/src/main/java/com/vitorpamplona/amethyst/model/UiSettings.kt

@@ -54,6 +54,11 @@ data class UiSettings(
     val showProfileFollowersFeed: Boolean = true,
     val dontShowOnchainPublicWarning: Boolean = false,
     val suggestWorkoutsFromHealthConnect: BooleanType = BooleanType.ALWAYS,
+    // Ids ([FavoriteApp.id][com.vitorpamplona.amethyst.commons.favorites.FavoriteApp.id]) of favorite
+    // apps the user activated as bottom-bar tabs, configured in the bottom-bar settings page. Kept
+    // separate from [bottomBarItems] (the built-in destinations) because favorites are dynamic data,
+    // not a fixed enum.
+    val bottomBarFavoriteIds: List<String> = emptyList(),
 )
 
 enum class ThemeType(

amethyst/src/main/java/com/vitorpamplona/amethyst/model/UiSettingsFlow.kt

@@ -54,6 +54,7 @@ class UiSettingsFlow(
     val showProfileFollowersFeed: MutableStateFlow<Boolean> = MutableStateFlow(true),
     val dontShowOnchainPublicWarning: MutableStateFlow<Boolean> = MutableStateFlow(false),
     val suggestWorkoutsFromHealthConnect: MutableStateFlow<BooleanType> = MutableStateFlow(BooleanType.ALWAYS),
+    val bottomBarFavoriteIds: MutableStateFlow<List<String>> = MutableStateFlow(emptyList()),
 ) {
     val listOfFlows: List<Flow<Any?>> =
         listOf<Flow<Any?>>(
@@ -82,6 +83,7 @@ class UiSettingsFlow(
             showProfileFollowersFeed,
             dontShowOnchainPublicWarning,
             suggestWorkoutsFromHealthConnect,
+            bottomBarFavoriteIds,
         )
 
     // emits at every change in any of the propertyes.
@@ -114,6 +116,7 @@ class UiSettingsFlow(
                 flows[22] as Boolean,
                 flows[23] as Boolean,
                 flows[24] as BooleanType,
+                flows[25] as List<String>,
             )
         }
 
@@ -144,6 +147,7 @@ class UiSettingsFlow(
             showProfileFollowersFeed.value,
             dontShowOnchainPublicWarning.value,
             suggestWorkoutsFromHealthConnect.value,
+            bottomBarFavoriteIds.value,
         )
 
     fun update(torSettings: UiSettings): Boolean {
@@ -249,6 +253,10 @@ class UiSettingsFlow(
             suggestWorkoutsFromHealthConnect.tryEmit(torSettings.suggestWorkoutsFromHealthConnect)
             any = true
         }
+        if (bottomBarFavoriteIds.value != torSettings.bottomBarFavoriteIds) {
+            bottomBarFavoriteIds.tryEmit(torSettings.bottomBarFavoriteIds)
+            any = true
+        }
 
         return any
     }
@@ -299,6 +307,7 @@ class UiSettingsFlow(
                 MutableStateFlow(uiSettings.showProfileFollowersFeed),
                 MutableStateFlow(uiSettings.dontShowOnchainPublicWarning),
                 MutableStateFlow(uiSettings.suggestWorkoutsFromHealthConnect),
+                MutableStateFlow(uiSettings.bottomBarFavoriteIds),
             )
     }
 }

amethyst/src/main/java/com/vitorpamplona/amethyst/model/preferences/UISharedPreferences.kt

@@ -109,6 +109,7 @@ class UiSharedPreferences(
         val UI_USE_TRACKED_BROADCASTS = stringPreferencesKey("ui.use_tracked_broadcasts")
         val UI_AUTOMATICALLY_CREATE_DRAFTS = stringPreferencesKey("ui.automatically_create_drafts")
         val UI_BOTTOM_BAR_ITEMS = stringPreferencesKey("ui.bottom_bar_items")
+        val UI_BOTTOM_BAR_FAVORITES = stringPreferencesKey("ui.bottom_bar_favorites")
         val UI_SHOW_HOME_NEW_THREADS_TAB = booleanPreferencesKey("ui.show_home_new_threads_tab")
         val UI_SHOW_HOME_CONVERSATIONS_TAB = booleanPreferencesKey("ui.show_home_conversations_tab")
         val UI_SHOW_HOME_EVERYTHING_TAB = booleanPreferencesKey("ui.show_home_everything_tab")
@@ -145,6 +146,7 @@ class UiSharedPreferences(
                             ?: if (featureSet == FeatureSetType.COMPLETE) BooleanType.ALWAYS else BooleanType.NEVER,
                     automaticallyCreateDrafts = preferences[UI_AUTOMATICALLY_CREATE_DRAFTS]?.let { BooleanType.valueOf(it) } ?: BooleanType.ALWAYS,
                     bottomBarItems = preferences[UI_BOTTOM_BAR_ITEMS]?.let { decodeBottomBarItems(it) } ?: DefaultBottomBarItems,
+                    bottomBarFavoriteIds = preferences[UI_BOTTOM_BAR_FAVORITES]?.let { decodeFavoriteIds(it) } ?: emptyList(),
                     showHomeNewThreadsTab = preferences[UI_SHOW_HOME_NEW_THREADS_TAB] ?: true,
                     showHomeConversationsTab = preferences[UI_SHOW_HOME_CONVERSATIONS_TAB] ?: true,
                     showHomeEverythingTab = preferences[UI_SHOW_HOME_EVERYTHING_TAB] ?: false,
@@ -195,6 +197,9 @@ class UiSharedPreferences(
                     preferences[UI_USE_TRACKED_BROADCASTS] = sharedSettings.useTrackedBroadcasts.name
                     preferences[UI_AUTOMATICALLY_CREATE_DRAFTS] = sharedSettings.automaticallyCreateDrafts.name
                     preferences[UI_BOTTOM_BAR_ITEMS] = sharedSettings.bottomBarItems.joinToString(",") { it.name }
+                    // Favorite ids contain ':' and '/' (urls / coordinates) but never a newline, so a
+                    // newline is a safe separator.
+                    preferences[UI_BOTTOM_BAR_FAVORITES] = sharedSettings.bottomBarFavoriteIds.joinToString("\n")
                     preferences[UI_SHOW_HOME_NEW_THREADS_TAB] = sharedSettings.showHomeNewThreadsTab
                     preferences[UI_SHOW_HOME_CONVERSATIONS_TAB] = sharedSettings.showHomeConversationsTab
                     preferences[UI_SHOW_HOME_EVERYTHING_TAB] = sharedSettings.showHomeEverythingTab
@@ -212,6 +217,8 @@ class UiSharedPreferences(
             }
         }
 
+        private fun decodeFavoriteIds(raw: String): List<String> = raw.split("\n").filter { it.isNotBlank() }
+
         private fun decodeBottomBarItems(raw: String): List<NavBarItem> {
             if (raw.isEmpty()) return emptyList()
             return raw

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/navigation/bottombars/AppBottomBar.kt

@@ -90,19 +90,21 @@ fun AppBottomBar(
         return
     }
 
-    // User-pinned favorite apps appear as extra tabs after the built-in items. Both kinds embed
-    // in-process (WebUrl → browser surface, NostrApp → napplet surface), so a pinned tab always
-    // swaps in place rather than launching an activity from the bottom row.
+    // Favorite apps the user activated as bottom-bar tabs (configured in the bottom-bar settings page,
+    // stored in ui settings — not auto-appended). Both kinds embed in-process (WebUrl → browser
+    // surface, NostrApp → napplet surface), so such a tab swaps in place rather than launching an
+    // activity from the bottom row.
     val favorites by FavoriteAppsRegistry.favorites.collectAsStateWithLifecycle()
-    val pinnedIds by FavoriteAppsRegistry.pinnedIds.collectAsStateWithLifecycle()
-    val pinnedFavorites =
-        remember(favorites, pinnedIds) {
-            pinnedIds.mapNotNull { id -> favorites.firstOrNull { it.id == id } }
+    val favoriteBarIds by accountViewModel.settings.uiSettingsFlow.bottomBarFavoriteIds
+        .collectAsStateWithLifecycle()
+    val favoriteTabs =
+        remember(favorites, favoriteBarIds) {
+            favoriteBarIds.mapNotNull { id -> favorites.firstOrNull { it.id == id } }
         }
 
     val isKeyboardState by keyboardAsState()
     if (isKeyboardState == KeyboardState.Closed) {
-        RenderBottomMenu(items, pinnedFavorites, selectedRoute, accountViewModel, onClick)
+        RenderBottomMenu(items, favoriteTabs, selectedRoute, accountViewModel, onClick)
     }
 }
 

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/favorites/FavoriteAppsScreen.kt

@@ -134,9 +134,6 @@ fun FavoriteAppsGrid(
     modifier: Modifier = Modifier,
     contentPadding: PaddingValues = PaddingValues(12.dp),
 ) {
-    // Any favorite can be pinned as a bottom-bar tab — both kinds embed in-process.
-    val pinnedIds by FavoriteAppsRegistry.pinnedIds.collectAsStateWithLifecycle()
-
     LazyVerticalGrid(
         columns = GridCells.Adaptive(96.dp),
         modifier = modifier,
@@ -147,8 +144,6 @@ fun FavoriteAppsGrid(
         items(apps, key = { it.id }) { app ->
             FavoriteAppCell(
                 app = app,
-                isPinned = pinnedIds.contains(app.id),
-                onTogglePin = { FavoriteAppsRegistry.setPinned(app.id, !FavoriteAppsRegistry.isPinned(app.id)) },
                 onOpen = { onOpen(app) },
                 onRemove = { onRemove(app) },
             )
@@ -160,8 +155,6 @@ fun FavoriteAppsGrid(
 @Composable
 private fun FavoriteAppCell(
     app: FavoriteApp,
-    isPinned: Boolean,
-    onTogglePin: (() -> Unit)?,
     onOpen: () -> Unit,
     onRemove: () -> Unit,
 ) {
@@ -203,16 +196,6 @@ private fun FavoriteAppCell(
         )
 
         DropdownMenu(expanded = menuOpen, onDismissRequest = { menuOpen = false }) {
-            onTogglePin?.let { toggle ->
-                DropdownMenuItem(
-                    text = { Text(stringResource(if (isPinned) R.string.favorite_app_unpin else R.string.favorite_app_pin)) },
-                    leadingIcon = { Icon(if (isPinned) MaterialSymbols.Star else MaterialSymbols.StarBorder, contentDescription = null) },
-                    onClick = {
-                        menuOpen = false
-                        toggle()
-                    },
-                )
-            }
             DropdownMenuItem(
                 text = { Text(stringResource(R.string.favorite_app_remove)) },
                 leadingIcon = { Icon(MaterialSymbols.Delete, contentDescription = null) },

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/settings/BottomBarSettingsScreen.kt

@@ -58,9 +58,12 @@ import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.zIndex
+import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import com.vitorpamplona.amethyst.R
+import com.vitorpamplona.amethyst.commons.favorites.FavoriteApp
 import com.vitorpamplona.amethyst.commons.icons.symbols.Icon
 import com.vitorpamplona.amethyst.commons.icons.symbols.MaterialSymbols
+import com.vitorpamplona.amethyst.favorites.FavoriteAppsRegistry
 import com.vitorpamplona.amethyst.ui.navigation.bottombars.DefaultBottomBarItems
 import com.vitorpamplona.amethyst.ui.navigation.bottombars.NavBarCatalog
 import com.vitorpamplona.amethyst.ui.navigation.bottombars.NavBarItem
@@ -258,10 +261,64 @@ fun BottomBarSettingsContent(accountViewModel: AccountViewModel) {
             }
         }
 
+        FavoriteAppsSection(accountViewModel)
+
         Spacer(modifier = Modifier.height(16.dp))
     }
 }
 
+/**
+ * Lets the user activate individual favorite apps (nsites / napplets / web clients) as bottom-bar tabs.
+ * A separate section from the built-in destinations above: favorites are dynamic data, stored as
+ * [com.vitorpamplona.amethyst.model.UiSettings.bottomBarFavoriteIds], not the fixed [NavBarItem] enum.
+ * (The "All apps" grid itself is a built-in destination in the list above.)
+ */
+@Composable
+private fun FavoriteAppsSection(accountViewModel: AccountViewModel) {
+    val favorites by FavoriteAppsRegistry.favorites.collectAsStateWithLifecycle()
+    if (favorites.isEmpty()) return
+
+    val flow = accountViewModel.settings.uiSettingsFlow.bottomBarFavoriteIds
+    val activeIds by flow.collectAsStateWithLifecycle()
+
+    SectionDivider(R.string.bottom_bar_settings_favorite_apps)
+
+    favorites.forEach { app ->
+        val checked = app.id in activeIds
+        Row(
+            modifier =
+                Modifier
+                    .fillMaxWidth()
+                    .padding(vertical = 8.dp, horizontal = Size20dp),
+            verticalAlignment = Alignment.CenterVertically,
+            horizontalArrangement = Arrangement.spacedBy(12.dp),
+        ) {
+            Box(modifier = Modifier.size(28.dp), contentAlignment = Alignment.Center) {
+                Icon(
+                    symbol = if (app is FavoriteApp.NostrApp) MaterialSymbols.Apps else MaterialSymbols.Public,
+                    contentDescription = null,
+                    modifier = Modifier.size(24.dp),
+                    tint = MaterialTheme.colorScheme.onBackground,
+                )
+            }
+            Text(
+                text = app.label,
+                style = MaterialTheme.typography.bodyLarge,
+                maxLines = 1,
+                overflow = TextOverflow.Ellipsis,
+                modifier = Modifier.weight(1f),
+            )
+            Switch(
+                checked = checked,
+                onCheckedChange = { on ->
+                    flow.tryEmit(if (on) activeIds + app.id else activeIds - app.id)
+                },
+            )
+        }
+        HorizontalDivider(modifier = Modifier.padding(horizontal = Size20dp))
+    }
+}
+
 private data class Row(
     val item: NavBarItem,
     val pinned: Boolean,

amethyst/src/main/res/values/strings.xml

@@ -678,8 +678,7 @@
     <string name="favorite_app_add">Add to favorites</string>
     <string name="favorite_app_remove">Remove from favorites</string>
     <string name="favorite_app_open_window">Open in its own window</string>
-    <string name="favorite_app_pin">Pin to bottom bar</string>
-    <string name="favorite_app_unpin">Unpin from bottom bar</string>
+    <string name="bottom_bar_settings_favorite_apps">Favorite apps</string>
     <string name="favorite_app_access_title">What this app can access</string>
     <string name="favorite_app_access_static">Runs sandboxed with no special access to your account.</string>
     <string name="favorite_app_access_show">What it can access</string>