fix(client/android): clear all favorites when other settings are reset (#6707)

This required some refactoring since we want to move away from
`LiveData` and towards `StateFlow`

Closes #6293

kotlin/android/app/src/main/java/dev/firezone/android/core/data/Repository.kt

@@ -10,6 +10,8 @@ import dev.firezone.android.BuildConfig
 import dev.firezone.android.core.data.model.Config
 import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.asStateFlow
 import kotlinx.coroutines.flow.flow
 import kotlinx.coroutines.flow.flowOn
 import java.security.MessageDigest
@@ -49,6 +51,10 @@ fun ResourceState.toggle(): ResourceState {
     }
 }
 
+// Wrapper class used because `MutableStateFlow` will not
+// notify subscribers if you submit the same object that's already in it.
+class Favorites(val inner: HashSet<String>)
+
 internal class Repository
     @Inject
     constructor(
@@ -56,6 +62,12 @@ internal class Repository
         private val coroutineDispatcher: CoroutineDispatcher,
         private val sharedPreferences: SharedPreferences,
     ) {
+        // We are the only thing that can modify favorites so we shouldn't need to reload it after
+        // this initial load
+        private val _favorites =
+            MutableStateFlow(Favorites(HashSet(sharedPreferences.getStringSet(FAVORITE_RESOURCES_KEY, null).orEmpty())))
+        val favorites = _favorites.asStateFlow()
+
         fun getConfigSync(): Config {
             return Config(
                 sharedPreferences.getString(AUTH_BASE_URL_KEY, null)
@@ -98,9 +110,25 @@ internal class Repository
 
         fun getDeviceIdSync(): String? = sharedPreferences.getString(DEVICE_ID_KEY, null)
 
-        fun getFavoritesSync(): HashSet<String> = HashSet(sharedPreferences.getStringSet(FAVORITE_RESOURCES_KEY, null).orEmpty())
+        private fun saveFavoritesSync() {
+            sharedPreferences.edit().putStringSet(FAVORITE_RESOURCES_KEY, favorites.value.inner).apply()
+            _favorites.value = Favorites(favorites.value.inner)
+        }
 
-        fun saveFavoritesSync(value: HashSet<String>) = sharedPreferences.edit().putStringSet(FAVORITE_RESOURCES_KEY, value).apply()
+        fun addFavoriteResource(id: String) {
+            favorites.value.inner.add(id)
+            saveFavoritesSync()
+        }
+
+        fun removeFavoriteResource(id: String) {
+            favorites.value.inner.remove(id)
+            saveFavoritesSync()
+        }
+
+        fun resetFavorites() {
+            favorites.value.inner.clear()
+            saveFavoritesSync()
+        }
 
         fun getToken(): Flow<String?> =
             flow {

kotlin/android/app/src/main/java/dev/firezone/android/core/di/DataModule.kt

@@ -12,6 +12,7 @@ import dagger.hilt.android.qualifiers.ApplicationContext
 import dagger.hilt.components.SingletonComponent
 import dev.firezone.android.core.data.Repository
 import kotlinx.coroutines.CoroutineDispatcher
+import javax.inject.Singleton
 
 @Module
 @InstallIn(SingletonComponent::class)
@@ -21,6 +22,7 @@ class DataModule {
         @ApplicationContext context: Context,
     ): Bundle = (context.getSystemService(Context.RESTRICTIONS_SERVICE) as android.content.RestrictionsManager).applicationRestrictions
 
+    @Singleton
     @Provides
     internal fun provideRepository(
         @ApplicationContext context: Context,

kotlin/android/app/src/main/java/dev/firezone/android/features/session/ui/ResourceDetailsBottomSheet.kt

@@ -172,7 +172,7 @@ class ResourceDetailsBottomSheet(
     private fun refreshButtons() {
         val addToFavoritesBtn: MaterialButton = view.findViewById(R.id.addToFavoritesBtn)
         val removeFromFavoritesBtn: MaterialButton = view.findViewById(R.id.removeFromFavoritesBtn)
-        val isFavorite = viewModel.favoriteResourcesLiveData.value!!.contains(resource.id)
+        val isFavorite = viewModel.isFavorite(resource.id)
         addToFavoritesBtn.visibility = if (isFavorite) View.GONE else View.VISIBLE
         removeFromFavoritesBtn.visibility = if (isFavorite) View.VISIBLE else View.GONE
     }

kotlin/android/app/src/main/java/dev/firezone/android/features/session/ui/SessionActivity.kt

@@ -8,9 +8,9 @@ import android.content.ServiceConnection
 import android.os.Bundle
 import android.os.IBinder
 import android.util.Log
-import android.view.View
 import androidx.activity.viewModels
 import androidx.appcompat.app.AppCompatActivity
+import androidx.lifecycle.lifecycleScope
 import androidx.recyclerview.widget.DividerItemDecoration
 import androidx.recyclerview.widget.LinearLayoutManager
 import com.google.android.material.tabs.TabLayout
@@ -20,6 +20,7 @@ import dev.firezone.android.core.data.toggle
 import dev.firezone.android.databinding.ActivitySessionBinding
 import dev.firezone.android.features.settings.ui.SettingsActivity
 import dev.firezone.android.tunnel.TunnelService
+import kotlinx.coroutines.launch
 
 @AndroidEntryPoint
 class SessionActivity : AppCompatActivity() {
@@ -129,6 +130,7 @@ class SessionActivity : AppCompatActivity() {
                 override fun onTabReselected(tab: TabLayout.Tab) {}
             },
         )
+        viewModel.tabSelected(binding.tabLayout.selectedTabPosition)
     }
 
     private fun setupObservers() {
@@ -143,24 +145,20 @@ class SessionActivity : AppCompatActivity() {
             refreshList()
         }
 
-        viewModel.favoriteResourcesLiveData.observe(this) {
-            refreshList()
+        // This coroutine could still resume while the Activity is not shown, but this is probably
+        // fine since the Flow will only emit if the user interacts with the UI anyway.
+        lifecycleScope.launch {
+            viewModel.favorites.collect {
+                refreshList()
+            }
         }
         viewModel.tabSelected(binding.tabLayout.selectedTabPosition)
-        viewModel.favoriteResourcesLiveData.value = viewModel.repo.getFavoritesSync()
     }
 
     private fun refreshList(afterLoad: () -> Unit = {}) {
-        if (viewModel.forceAllResourcesTab()) {
-            binding.tabLayout.selectTab(binding.tabLayout.getTabAt(SessionViewModel.RESOURCES_TAB_ALL), true)
-        }
-        binding.tabLayout.visibility =
-            if (viewModel.showFavoritesTab()) {
-                View.VISIBLE
-            } else {
-                View.GONE
-            }
+        viewModel.forceTab()?.let { tab -> binding.tabLayout.selectTab(binding.tabLayout.getTabAt(tab), true) }
 
+        binding.tabLayout.visibility = viewModel.tabLayoutVisibility()
         resourcesAdapter.submitList(viewModel.resourcesList(internetState())) {
             afterLoad()
         }

kotlin/android/app/src/main/java/dev/firezone/android/features/session/ui/SessionViewModel.kt

@@ -1,36 +1,36 @@
 /* Licensed under Apache 2.0 (C) 2024 Firezone, Inc. */
 package dev.firezone.android.features.session.ui
 
+import android.view.View
 import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.ViewModel
 import dagger.hilt.android.lifecycle.HiltViewModel
+import dev.firezone.android.core.data.Favorites
 import dev.firezone.android.core.data.Repository
 import dev.firezone.android.core.data.ResourceState
 import dev.firezone.android.tunnel.TunnelService.Companion.State
 import dev.firezone.android.tunnel.model.Resource
 import dev.firezone.android.tunnel.model.isInternetResource
+import kotlinx.coroutines.flow.StateFlow
 import javax.inject.Inject
 
 @HiltViewModel
 internal class SessionViewModel
     @Inject
     constructor() : ViewModel() {
+        // Must be `internal` because Dagger does not support injection into `private` fields
         @Inject
         internal lateinit var repo: Repository
-        private val _favoriteResourcesLiveData = MutableLiveData<HashSet<String>>(HashSet())
         private val _serviceStatusLiveData = MutableLiveData<State>()
         private val _resourcesLiveData = MutableLiveData<List<Resource>>(emptyList())
-        private var showOnlyFavorites: Boolean = false
+        private var selectedTab = RESOURCES_TAB_FAVORITES
 
-        val favoriteResourcesLiveData: MutableLiveData<HashSet<String>>
-            get() = _favoriteResourcesLiveData
         val serviceStatusLiveData: MutableLiveData<State>
             get() = _serviceStatusLiveData
         val resourcesLiveData: MutableLiveData<List<Resource>>
             get() = _resourcesLiveData
-
-        private val favoriteResources: HashSet<String>
-            get() = favoriteResourcesLiveData.value!!
+        val favorites: StateFlow<Favorites>
+            get() = repo.favorites
 
         // Actor name
         fun clearActorName() = repo.clearActorName()
@@ -38,22 +38,11 @@ internal class SessionViewModel
         fun getActorName() = repo.getActorNameSync()
 
         fun addFavoriteResource(id: String) {
-            val value = favoriteResources
-            value.add(id)
-            repo.saveFavoritesSync(value)
-            // Update LiveData
-            _favoriteResourcesLiveData.value = value
+            repo.addFavoriteResource(id)
         }
 
         fun removeFavoriteResource(id: String) {
-            val value = favoriteResources
-            value.remove(id)
-            repo.saveFavoritesSync(value)
-            if (forceAllResourcesTab()) {
-                showOnlyFavorites = false
-            }
-            // Update LiveData
-            _favoriteResourcesLiveData.value = value
+            repo.removeFavoriteResource(id)
         }
 
         fun clearToken() = repo.clearToken()
@@ -69,40 +58,37 @@ internal class SessionViewModel
                     }
                 }
 
-            return if (favoriteResources.isEmpty()) {
+            return if (repo.favorites.value.inner.isEmpty()) {
                 resources
-            } else if (showOnlyFavorites) {
-                resources.filter { favoriteResources.contains(it.id) }
+            } else if (selectedTab == RESOURCES_TAB_FAVORITES) {
+                resources.filter { repo.favorites.value.inner.contains(it.id) }
             } else {
                 resources
             }
         }
 
-        fun forceAllResourcesTab(): Boolean {
-            return favoriteResources.isEmpty()
-        }
-
-        fun showFavoritesTab(): Boolean {
-            return favoriteResources.isNotEmpty()
-        }
+        fun forceTab(): Int? =
+            if (repo.favorites.value.inner.isEmpty()) {
+                RESOURCES_TAB_ALL
+            } else {
+                null
+            }
 
         fun tabSelected(position: Int) {
-            showOnlyFavorites =
-                when (position) {
-                    RESOURCES_TAB_FAVORITES -> {
-                        true
-                    }
-
-                    RESOURCES_TAB_ALL -> {
-                        false
-                    }
-
-                    else -> throw IllegalArgumentException("Invalid tab position: $position")
-                }
+            selectedTab = position
         }
 
+        fun isFavorite(id: String) = repo.favorites.value.inner.contains(id)
+
+        fun tabLayoutVisibility(): Int =
+            if (repo.favorites.value.inner.isNotEmpty()) {
+                View.VISIBLE
+            } else {
+                View.GONE
+            }
+
         companion object {
-            const val RESOURCES_TAB_FAVORITES = 0
-            const val RESOURCES_TAB_ALL = 1
+            private const val RESOURCES_TAB_FAVORITES = 0
+            private const val RESOURCES_TAB_ALL = 1
         }
     }

kotlin/android/app/src/main/java/dev/firezone/android/features/settings/ui/SettingsViewModel.kt

@@ -144,6 +144,7 @@ internal class SettingsViewModel
 
         fun resetSettingsToDefaults() {
             config = repo.getDefaultConfigSync()
+            repo.resetFavorites()
             onFieldUpdated()
             actionMutableLiveData.postValue(
                 ViewAction.FillSettings(config),

website/src/components/Changelog/Android.tsx

@@ -9,6 +9,15 @@ export default function Android() {
       href="https://play.google.com/store/apps/details?id=dev.firezone.android"
       title="Android"
     >
+      {/*
+      <Entry version="1.3.3" date={new Date("todo")}>
+        <ul className="list-disc space-y-2 pl-4 mb-4">
+          <ChangeItem pull="6707">
+            Resetting the settings now resets the list of favorited Resources, too.
+          </ChangeItem>
+        </ul>
+      </Entry>
+      */}
       <Entry version="1.3.2" date={new Date("2024-09-05")}>
         <ul className="list-disc space-y-2 pl-4 mb-4">
           <ChangeItem pull="6605">