From d3cbcc41791c1e9db4ef55c4e6e0e392cb5dee2c Mon Sep 17 00:00:00 2001
From: Paul Woitaschek <woitaschek@posteo.de>
Date: Sat, 27 Dec 2025 20:24:07 +0100
Subject: [PATCH] Move folder picker to settings behind feature flag (#3280)

* Refactor: Introduce a feature flag module

Introduces a new `core:featureflag` module to abstract feature flag implementations. This module provides a `FeatureFlag` interface and a `FeatureFlagFactory` to create feature flags backed by `RemoteConfig`.

Key changes include:
- Creating a new `:core:featureflag` Gradle module.
- Replacing direct `RemoteConfig` usage in `features/cover` and `features/review` with the new `FeatureFlag` abstraction.
- Using a `MemoryFeatureFlag` for testing purposes.

* Move folder picker to settings behind feature flag

This change introduces a feature flag `folder_picker_in_settings`.

When this flag is enabled:
- The folder picker icon is removed from the book overview top bar.
- A new entry to access the audiobook folder management screen is added to the settings menu.

Additionally, feature flag definitions have been centralized into a single `FeatureFlagBindingContainer` for better organization.

* Delete docs/feature-specs/folder_picker_in_settings.md
---
 .idea/inspectionProfiles/ktlint.xml           |  1 +
 .../FeatureFlagBindingContainer.kt            | 41 +++++++++++++++++++
 .../core/featureflag/FeatureFlagFactory.kt    |  7 +++-
 core/strings/src/main/res/values/strings.xml  |  1 +
 features/bookOverview/build.gradle.kts        |  1 +
 .../overview/BookOverviewViewModel.kt         |  5 +++
 .../overview/BookOverviewViewState.kt         |  2 +
 .../bookOverview/views/BookOverview.kt        |  1 +
 .../views/topbar/BookOverviewSearchBar.kt     |  2 +
 .../views/topbar/BookOverviewTopBar.kt        |  2 +
 .../views/topbar/TopBarTrailingIcon.kt        |  5 ++-
 .../voice/features/cover/api/CoverModule.kt   |  9 +---
 features/folderPicker/build.gradle.kts        |  1 +
 .../features/review/ShouldShowReviewDialog.kt |  1 +
 features/settings/build.gradle.kts            |  2 +-
 .../features/settings/SettingsListener.kt     |  2 +
 .../features/settings/SettingsViewModel.kt    | 12 ++++++
 .../features/settings/SettingsViewState.kt    |  2 +
 .../voice/features/settings/views/Settings.kt | 20 +++++++++
 19 files changed, 105 insertions(+), 12 deletions(-)
 create mode 100644 core/featureflag/src/main/kotlin/voice/core/featureflag/FeatureFlagBindingContainer.kt

diff --git a/.idea/inspectionProfiles/ktlint.xml b/.idea/inspectionProfiles/ktlint.xml
index 87e170f75..75a5b63dd 100644
--- a/.idea/inspectionProfiles/ktlint.xml
+++ b/.idea/inspectionProfiles/ktlint.xml
@@ -73,5 +73,6 @@
       <option name="composableFile" value="true" />
       <option name="previewFile" value="true" />
     </inspection_tool>
+    <inspection_tool class="RedundantCompanionReference" enabled="true" level="ERROR" enabled_by_default="true" editorAttributes="ERRORS_ATTRIBUTES" />
   </profile>
 </component>
\ No newline at end of file
diff --git a/core/featureflag/src/main/kotlin/voice/core/featureflag/FeatureFlagBindingContainer.kt b/core/featureflag/src/main/kotlin/voice/core/featureflag/FeatureFlagBindingContainer.kt
new file mode 100644
index 000000000..ba498b4b0
--- /dev/null
+++ b/core/featureflag/src/main/kotlin/voice/core/featureflag/FeatureFlagBindingContainer.kt
@@ -0,0 +1,41 @@
+package voice.core.featureflag
+
+import dev.zacsweers.metro.AppScope
+import dev.zacsweers.metro.BindingContainer
+import dev.zacsweers.metro.ContributesTo
+import dev.zacsweers.metro.Provides
+import dev.zacsweers.metro.Qualifier
+import dev.zacsweers.metro.SingleIn
+
+@BindingContainer
+@ContributesTo(AppScope::class)
+object FeatureFlagBindingContainer {
+
+  @Provides
+  @SingleIn(AppScope::class)
+  @ReviewEnabledFeatureFlagQualifier
+  fun reviewEnabledFeatureFlag(factory: FeatureFlagFactory): FeatureFlag<Boolean> = factory.boolean("review_enabled", defaultValue = false)
+
+  @Provides
+  @SingleIn(AppScope::class)
+  @UserAgentFeatureFlagQualifier
+  fun userAgentFeatureFlag(factory: FeatureFlagFactory): FeatureFlag<String> {
+    return factory.string(key = "user_agent", defaultValue = "Mozilla/5.0")
+  }
+
+  @Provides
+  @SingleIn(AppScope::class)
+  @FolderPickerInSettingsFeatureFlagQualifier
+  fun folderPickerInSettingsFeatureFlag(factory: FeatureFlagFactory): FeatureFlag<Boolean> {
+    return factory.boolean(key = "folder_picker_in_settings")
+  }
+}
+
+@Qualifier
+annotation class ReviewEnabledFeatureFlagQualifier
+
+@Qualifier
+annotation class UserAgentFeatureFlagQualifier
+
+@Qualifier
+annotation class FolderPickerInSettingsFeatureFlagQualifier
diff --git a/core/featureflag/src/main/kotlin/voice/core/featureflag/FeatureFlagFactory.kt b/core/featureflag/src/main/kotlin/voice/core/featureflag/FeatureFlagFactory.kt
index 2dc0a446c..8e2637fb1 100644
--- a/core/featureflag/src/main/kotlin/voice/core/featureflag/FeatureFlagFactory.kt
+++ b/core/featureflag/src/main/kotlin/voice/core/featureflag/FeatureFlagFactory.kt
@@ -6,9 +6,12 @@ import voice.core.remoteconfig.api.RemoteConfig
 @Inject
 class FeatureFlagFactory(private val remoteConfig: RemoteConfig) {
 
-  fun boolean(key: String): FeatureFlag<Boolean> {
+  fun boolean(
+    key: String,
+    defaultValue: Boolean = false,
+  ): FeatureFlag<Boolean> {
     return RemoteConfigFeatureFlag(remoteConfig = remoteConfig) {
-      it.boolean(key = key)
+      it.boolean(key = key, defaultValue = defaultValue)
     }
   }
 
diff --git a/core/strings/src/main/res/values/strings.xml b/core/strings/src/main/res/values/strings.xml
index 925492eba..dc6efa402 100644
--- a/core/strings/src/main/res/values/strings.xml
+++ b/core/strings/src/main/res/values/strings.xml
@@ -27,6 +27,7 @@
     <string name="mark_as_current">Mark as Current</string>
     <string name="mark_as_not_started">Mark as Not Started Yet</string>
     <string name="audiobook_folders_title">Audiobook folders</string>
+    <string name="pref_audiobook_folders_explanation">Manage folders scanned for audiobooks</string>
     <string name="playback_speed">Playback speed</string>
     <string name="bookmark">Bookmark</string>
     <string name="bookmark_edit_title">Edit bookmark</string>
diff --git a/features/bookOverview/build.gradle.kts b/features/bookOverview/build.gradle.kts
index 033905f17..e951c99cc 100644
--- a/features/bookOverview/build.gradle.kts
+++ b/features/bookOverview/build.gradle.kts
@@ -13,6 +13,7 @@ dependencies {
   implementation(projects.core.playback)
   implementation(projects.core.data.api)
   implementation(projects.core.scanner)
+  implementation(projects.core.featureflag)
 
   implementation(libs.lifecycle)
   api(libs.immutable)
diff --git a/features/bookOverview/src/main/kotlin/voice/features/bookOverview/overview/BookOverviewViewModel.kt b/features/bookOverview/src/main/kotlin/voice/features/bookOverview/overview/BookOverviewViewModel.kt
index e55a01293..e6381227a 100644
--- a/features/bookOverview/src/main/kotlin/voice/features/bookOverview/overview/BookOverviewViewModel.kt
+++ b/features/bookOverview/src/main/kotlin/voice/features/bookOverview/overview/BookOverviewViewModel.kt
@@ -25,6 +25,8 @@ import voice.core.data.repo.BookRepository
 import voice.core.data.repo.internals.dao.RecentBookSearchDao
 import voice.core.data.store.CurrentBookStore
 import voice.core.data.store.GridModeStore
+import voice.core.featureflag.FeatureFlag
+import voice.core.featureflag.FolderPickerInSettingsFeatureFlagQualifier
 import voice.core.playback.PlayerController
 import voice.core.playback.playstate.PlayStateManager
 import voice.core.scanner.DeviceHasStoragePermissionBug
@@ -53,6 +55,8 @@ class BookOverviewViewModel(
   private val search: BookSearch,
   private val contentRepo: BookContentRepo,
   private val deviceHasStoragePermissionBug: DeviceHasStoragePermissionBug,
+  @FolderPickerInSettingsFeatureFlagQualifier
+  private val folderPickerInSettingsFeatureFlag: FeatureFlag<Boolean>,
 ) {
 
   private val scope = MainScope()
@@ -123,6 +127,7 @@ class BookOverviewViewModel(
       searchActive = searchActive,
       searchViewState = bookSearchViewState,
       showStoragePermissionBugCard = hasStoragePermissionBug,
+      showFolderPickerIcon = !folderPickerInSettingsFeatureFlag.get(),
     )
   }
 
diff --git a/features/bookOverview/src/main/kotlin/voice/features/bookOverview/overview/BookOverviewViewState.kt b/features/bookOverview/src/main/kotlin/voice/features/bookOverview/overview/BookOverviewViewState.kt
index 81b858576..04932f4ad 100644
--- a/features/bookOverview/src/main/kotlin/voice/features/bookOverview/overview/BookOverviewViewState.kt
+++ b/features/bookOverview/src/main/kotlin/voice/features/bookOverview/overview/BookOverviewViewState.kt
@@ -16,6 +16,7 @@ data class BookOverviewViewState(
   val searchActive: Boolean,
   val searchViewState: BookSearchViewState,
   val showStoragePermissionBugCard: Boolean,
+  val showFolderPickerIcon: Boolean,
 ) {
 
   companion object {
@@ -33,6 +34,7 @@ data class BookOverviewViewState(
         query = "",
       ),
       showStoragePermissionBugCard = false,
+      showFolderPickerIcon = true,
     )
   }
 
diff --git a/features/bookOverview/src/main/kotlin/voice/features/bookOverview/views/BookOverview.kt b/features/bookOverview/src/main/kotlin/voice/features/bookOverview/views/BookOverview.kt
index a6f731597..b6c33e8c8 100644
--- a/features/bookOverview/src/main/kotlin/voice/features/bookOverview/views/BookOverview.kt
+++ b/features/bookOverview/src/main/kotlin/voice/features/bookOverview/views/BookOverview.kt
@@ -276,6 +276,7 @@ internal class BookOverviewPreviewParameterProvider : PreviewParameterProvider<B
         query = "",
       ),
       showStoragePermissionBugCard = false,
+      showFolderPickerIcon = true,
     ),
   )
 }
diff --git a/features/bookOverview/src/main/kotlin/voice/features/bookOverview/views/topbar/BookOverviewSearchBar.kt b/features/bookOverview/src/main/kotlin/voice/features/bookOverview/views/topbar/BookOverviewSearchBar.kt
index eaff83e4a..e20645f2f 100644
--- a/features/bookOverview/src/main/kotlin/voice/features/bookOverview/views/topbar/BookOverviewSearchBar.kt
+++ b/features/bookOverview/src/main/kotlin/voice/features/bookOverview/views/topbar/BookOverviewSearchBar.kt
@@ -23,6 +23,7 @@ internal fun ColumnScope.BookOverviewSearchBar(
   onSearchBookClick: (BookId) -> Unit,
   searchActive: Boolean,
   showAddBookHint: Boolean,
+  showFolderPickerIcon: Boolean,
   searchViewState: BookSearchViewState,
 ) {
   SearchBar(
@@ -47,6 +48,7 @@ internal fun ColumnScope.BookOverviewSearchBar(
           TopBarTrailingIcon(
             searchActive = searchActive,
             showAddBookHint = showAddBookHint,
+            showFolderPickerIcon = showFolderPickerIcon,
             onBookFolderClick = onBookFolderClick,
             onSettingsClick = onSettingsClick,
           )
diff --git a/features/bookOverview/src/main/kotlin/voice/features/bookOverview/views/topbar/BookOverviewTopBar.kt b/features/bookOverview/src/main/kotlin/voice/features/bookOverview/views/topbar/BookOverviewTopBar.kt
index 609ffbe19..5ddb01f16 100644
--- a/features/bookOverview/src/main/kotlin/voice/features/bookOverview/views/topbar/BookOverviewTopBar.kt
+++ b/features/bookOverview/src/main/kotlin/voice/features/bookOverview/views/topbar/BookOverviewTopBar.kt
@@ -46,6 +46,7 @@ internal fun BookOverviewTopBar(
       onSearchBookClick = onSearchBookClick,
       searchActive = viewState.searchActive,
       showAddBookHint = viewState.showAddBookHint,
+      showFolderPickerIcon = viewState.showFolderPickerIcon,
       searchViewState = viewState.searchViewState,
     )
     var showLoading by remember { mutableStateOf(true) }
@@ -84,6 +85,7 @@ private fun BookOverviewTopBarPreview() {
           query = "",
         ),
         showStoragePermissionBugCard = false,
+        showFolderPickerIcon = true,
       ),
       onBookFolderClick = {},
       onSettingsClick = {},
diff --git a/features/bookOverview/src/main/kotlin/voice/features/bookOverview/views/topbar/TopBarTrailingIcon.kt b/features/bookOverview/src/main/kotlin/voice/features/bookOverview/views/topbar/TopBarTrailingIcon.kt
index ff5d4ffbd..8a663b2eb 100644
--- a/features/bookOverview/src/main/kotlin/voice/features/bookOverview/views/topbar/TopBarTrailingIcon.kt
+++ b/features/bookOverview/src/main/kotlin/voice/features/bookOverview/views/topbar/TopBarTrailingIcon.kt
@@ -13,6 +13,7 @@ import voice.features.bookOverview.views.SettingsIcon
 internal fun ColumnScope.TopBarTrailingIcon(
   searchActive: Boolean,
   showAddBookHint: Boolean,
+  showFolderPickerIcon: Boolean,
   onBookFolderClick: () -> Unit,
   onSettingsClick: () -> Unit,
 ) {
@@ -22,7 +23,9 @@ internal fun ColumnScope.TopBarTrailingIcon(
     exit = fadeOut(),
   ) {
     Row {
-      BookFolderIcon(withHint = showAddBookHint, onClick = onBookFolderClick)
+      if (showFolderPickerIcon) {
+        BookFolderIcon(withHint = showAddBookHint, onClick = onBookFolderClick)
+      }
       SettingsIcon(onSettingsClick)
     }
   }
diff --git a/features/cover/src/main/kotlin/voice/features/cover/api/CoverModule.kt b/features/cover/src/main/kotlin/voice/features/cover/api/CoverModule.kt
index 96ae88c81..541680dc5 100644
--- a/features/cover/src/main/kotlin/voice/features/cover/api/CoverModule.kt
+++ b/features/cover/src/main/kotlin/voice/features/cover/api/CoverModule.kt
@@ -13,7 +13,7 @@ import retrofit2.converter.kotlinx.serialization.asConverterFactory
 import retrofit2.converter.scalars.ScalarsConverterFactory
 import retrofit2.create
 import voice.core.featureflag.FeatureFlag
-import voice.core.featureflag.FeatureFlagFactory
+import voice.core.featureflag.UserAgentFeatureFlagQualifier
 
 @ContributesTo(AppScope::class)
 @BindingContainer
@@ -52,11 +52,4 @@ object CoverModule {
       .build()
       .create()
   }
-
-  @Provides
-  @SingleIn(AppScope::class)
-  @UserAgentFeatureFlagQualifier
-  fun userAgentFeatureFlag(factory: FeatureFlagFactory): FeatureFlag<String> {
-    return factory.string(key = "user_agent", defaultValue = "Mozilla/5.0")
-  }
 }
diff --git a/features/folderPicker/build.gradle.kts b/features/folderPicker/build.gradle.kts
index dee711741..db62a5159 100644
--- a/features/folderPicker/build.gradle.kts
+++ b/features/folderPicker/build.gradle.kts
@@ -18,6 +18,7 @@ dependencies {
   implementation(projects.core.data.api)
   implementation(projects.core.documentfile)
   implementation(projects.navigation)
+  implementation(projects.core.featureflag)
 
   implementation(libs.datastore)
   implementation(libs.coil)
diff --git a/features/review/play/src/main/kotlin/voice/features/review/ShouldShowReviewDialog.kt b/features/review/play/src/main/kotlin/voice/features/review/ShouldShowReviewDialog.kt
index cf483086b..cefd45e43 100644
--- a/features/review/play/src/main/kotlin/voice/features/review/ShouldShowReviewDialog.kt
+++ b/features/review/play/src/main/kotlin/voice/features/review/ShouldShowReviewDialog.kt
@@ -6,6 +6,7 @@ import kotlinx.coroutines.flow.first
 import voice.core.data.repo.BookRepository
 import voice.core.data.store.ReviewDialogShownStore
 import voice.core.featureflag.FeatureFlag
+import voice.core.featureflag.ReviewEnabledFeatureFlagQualifier
 import voice.core.playback.playstate.PlayStateManager
 import java.time.Clock
 import java.time.temporal.ChronoUnit
diff --git a/features/settings/build.gradle.kts b/features/settings/build.gradle.kts
index b2446f8ad..8822e8c63 100644
--- a/features/settings/build.gradle.kts
+++ b/features/settings/build.gradle.kts
@@ -8,11 +8,11 @@ dependencies {
   implementation(projects.core.common)
   implementation(projects.navigation)
   implementation(projects.core.strings)
+  implementation(projects.core.featureflag)
   implementation(projects.core.playback)
   implementation(projects.core.ui)
   implementation(projects.core.data.api)
 
-  implementation(libs.androidxCore)
   implementation(libs.androidxCore)
   implementation(libs.material)
 }
diff --git a/features/settings/src/main/kotlin/voice/features/settings/SettingsListener.kt b/features/settings/src/main/kotlin/voice/features/settings/SettingsListener.kt
index 9d43cb2a7..2fc13aa64 100644
--- a/features/settings/src/main/kotlin/voice/features/settings/SettingsListener.kt
+++ b/features/settings/src/main/kotlin/voice/features/settings/SettingsListener.kt
@@ -20,6 +20,7 @@ interface SettingsListener {
   fun setAutoSleepTimerStart(time: LocalTime)
   fun setAutoSleepTimerEnd(time: LocalTime)
   fun toggleAnalytics()
+  fun openFolderPicker()
 
   companion object {
     fun noop() = object : SettingsListener {
@@ -40,6 +41,7 @@ interface SettingsListener {
       override fun setAutoSleepTimerStart(time: LocalTime) {}
       override fun setAutoSleepTimerEnd(time: LocalTime) {}
       override fun toggleAnalytics() {}
+      override fun openFolderPicker() {}
     }
   }
 }
diff --git a/features/settings/src/main/kotlin/voice/features/settings/SettingsViewModel.kt b/features/settings/src/main/kotlin/voice/features/settings/SettingsViewModel.kt
index 218c79a12..553b7f7e2 100644
--- a/features/settings/src/main/kotlin/voice/features/settings/SettingsViewModel.kt
+++ b/features/settings/src/main/kotlin/voice/features/settings/SettingsViewModel.kt
@@ -21,6 +21,8 @@ import voice.core.data.store.DarkThemeStore
 import voice.core.data.store.GridModeStore
 import voice.core.data.store.SeekTimeStore
 import voice.core.data.store.SleepTimerPreferenceStore
+import voice.core.featureflag.FeatureFlag
+import voice.core.featureflag.FolderPickerInSettingsFeatureFlagQualifier
 import voice.core.ui.DARK_THEME_SETTABLE
 import voice.core.ui.GridCount
 import voice.navigation.Destination
@@ -44,6 +46,8 @@ class SettingsViewModel(
   @AnalyticsConsentStore
   private val analyticsConsentStore: DataStore<Boolean>,
   private val gridCount: GridCount,
+  @FolderPickerInSettingsFeatureFlagQualifier
+  private val folderPickerInSettingsFeatureFlag: FeatureFlag<Boolean>,
   dispatcherProvider: DispatcherProvider,
 ) : SettingsListener {
 
@@ -60,6 +64,9 @@ class SettingsViewModel(
       initial = SleepTimerPreference.Default,
     )
     val analyticsEnabled by remember { analyticsConsentStore.data }.collectAsState(initial = false)
+    val showFolderPickerEntry = remember {
+      folderPickerInSettingsFeatureFlag.get()
+    }
     return SettingsViewState(
       useDarkTheme = useDarkTheme,
       showDarkThemePref = DARK_THEME_SETTABLE,
@@ -79,6 +86,7 @@ class SettingsViewModel(
       ),
       analyticsEnabled = analyticsEnabled,
       showAnalyticSetting = appInfoProvider.analyticsIncluded,
+      showFolderPickerEntry = showFolderPickerEntry,
     )
   }
 
@@ -160,6 +168,10 @@ class SettingsViewModel(
     navigator.goTo(Destination.Website("https://voice.woitaschek.de/faq/"))
   }
 
+  override fun openFolderPicker() {
+    navigator.goTo(Destination.FolderPicker)
+  }
+
   override fun setAutoSleepTimer(checked: Boolean) {
     mainScope.launch {
       sleepTimerPreferenceStore.updateData { currentPrefs ->
diff --git a/features/settings/src/main/kotlin/voice/features/settings/SettingsViewState.kt b/features/settings/src/main/kotlin/voice/features/settings/SettingsViewState.kt
index d4a484e27..b93613d7b 100644
--- a/features/settings/src/main/kotlin/voice/features/settings/SettingsViewState.kt
+++ b/features/settings/src/main/kotlin/voice/features/settings/SettingsViewState.kt
@@ -13,6 +13,7 @@ data class SettingsViewState(
   val autoSleepTimer: AutoSleepTimerViewState,
   val showAnalyticSetting: Boolean,
   val analyticsEnabled: Boolean,
+  val showFolderPickerEntry: Boolean,
 ) {
 
   enum class Dialog {
@@ -33,6 +34,7 @@ data class SettingsViewState(
         autoSleepTimer = AutoSleepTimerViewState.preview(),
         analyticsEnabled = false,
         showAnalyticSetting = true,
+        showFolderPickerEntry = false,
       )
     }
   }
diff --git a/features/settings/src/main/kotlin/voice/features/settings/views/Settings.kt b/features/settings/src/main/kotlin/voice/features/settings/views/Settings.kt
index b05fad1ef..00759bebc 100644
--- a/features/settings/src/main/kotlin/voice/features/settings/views/Settings.kt
+++ b/features/settings/src/main/kotlin/voice/features/settings/views/Settings.kt
@@ -6,6 +6,7 @@ import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.automirrored.outlined.HelpOutline
 import androidx.compose.material.icons.automirrored.outlined.ViewList
 import androidx.compose.material.icons.outlined.Analytics
+import androidx.compose.material.icons.outlined.Book
 import androidx.compose.material.icons.outlined.BugReport
 import androidx.compose.material.icons.outlined.Close
 import androidx.compose.material.icons.outlined.GridView
@@ -81,6 +82,25 @@ private fun Settings(
     },
   ) { contentPadding ->
     LazyColumn(contentPadding = contentPadding) {
+      if (viewState.showFolderPickerEntry) {
+        item {
+          ListItem(
+            modifier = Modifier.clickable { listener.openFolderPicker() },
+            leadingContent = {
+              Icon(
+                imageVector = Icons.Outlined.Book,
+                contentDescription = stringResource(StringsR.string.audiobook_folders_title),
+              )
+            },
+            headlineContent = {
+              Text(stringResource(StringsR.string.audiobook_folders_title))
+            },
+            supportingContent = {
+              Text(stringResource(StringsR.string.pref_audiobook_folders_explanation))
+            },
+          )
+        }
+      }
       if (viewState.showDarkThemePref) {
         item {
           DarkThemeRow(viewState.useDarkTheme, listener::toggleDarkTheme)