Add followedTopicsState in ForYouViewModel

Change-Id: I30e243a8cbfa46e3d3f61a5f1feb1b514cfba9c5

core/ui/src/main/java/com/google/samples/apps/nowinandroid/core/ui/NewsFeed.kt

@@ -37,6 +37,7 @@ import androidx.compose.ui.tooling.preview.Devices
 import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import com.google.samples.apps.nowinandroid.core.designsystem.theme.NiaTheme
+import com.google.samples.apps.nowinandroid.core.domain.model.FollowableTopic
 import com.google.samples.apps.nowinandroid.core.domain.model.SaveableNewsResource
 import com.google.samples.apps.nowinandroid.core.model.data.previewNewsResources
 
@@ -61,6 +62,7 @@ fun LazyGridScope.newsFeed(
                 NewsResourceCardExpanded(
                     newsResource = saveableNewsResource.newsResource,
                     isBookmarked = saveableNewsResource.isSaved,
+                    // ToDo add list of followed topics
                     onClick = { launchCustomChromeTab(context, resourceUrl, backgroundColor) },
                     onToggleBookmark = {
                         onNewsResourcesCheckedChanged(
@@ -104,6 +106,18 @@ sealed interface NewsFeedUiState {
     ) : NewsFeedUiState
 }
 
+/**
+ * A sealed hierarchy describing the state of the followed topics
+ */
+sealed interface FollowedTopicsState {
+
+    object Loading : FollowedTopicsState
+
+    data class Topics(
+        val topics: List<FollowableTopic>
+    ) : FollowedTopicsState
+}
+
 @Preview
 @Composable
 fun NewsFeedLoadingPreview() {

feature/foryou/src/main/java/com/google/samples/apps/nowinandroid/feature/foryou/ForYouScreen.kt

@@ -99,12 +99,14 @@ internal fun ForYouRoute(
 ) {
     val onboardingUiState by viewModel.onboardingUiState.collectAsStateWithLifecycle()
     val feedState by viewModel.feedState.collectAsStateWithLifecycle()
+    val followedTopicsState by viewModel.followedTopicsState.collectAsStateWithLifecycle()
     val isSyncing by viewModel.isSyncing.collectAsStateWithLifecycle()
 
     ForYouScreen(
         isSyncing = isSyncing,
         onboardingUiState = onboardingUiState,
         feedState = feedState,
+        followedTopicsState = followedTopicsState,
         onTopicCheckedChanged = viewModel::updateTopicSelection,
         saveFollowedTopics = viewModel::dismissOnboarding,
         onNewsResourcesCheckedChanged = viewModel::updateNewsResourceSaved,
@@ -117,6 +119,7 @@ internal fun ForYouScreen(
     isSyncing: Boolean,
     onboardingUiState: OnboardingUiState,
     feedState: NewsFeedUiState,
+    followedTopicsState:
     onTopicCheckedChanged: (String, Boolean) -> Unit,
     saveFollowedTopics: () -> Unit,
     onNewsResourcesCheckedChanged: (String, Boolean) -> Unit,
@@ -176,6 +179,7 @@ internal fun ForYouScreen(
 
         newsFeed(
             feedState = feedState,
+            // ToDo : add followed topics list
             onNewsResourcesCheckedChanged = onNewsResourcesCheckedChanged,
         )
 

feature/foryou/src/main/java/com/google/samples/apps/nowinandroid/feature/foryou/ForYouViewModel.kt

@@ -22,7 +22,9 @@ import com.google.samples.apps.nowinandroid.core.data.repository.UserDataReposit
 import com.google.samples.apps.nowinandroid.core.data.util.SyncStatusMonitor
 import com.google.samples.apps.nowinandroid.core.domain.GetFollowableTopicsUseCase
 import com.google.samples.apps.nowinandroid.core.domain.GetSaveableNewsResourcesUseCase
+import com.google.samples.apps.nowinandroid.core.domain.TopicSortField
 import com.google.samples.apps.nowinandroid.core.domain.model.SaveableNewsResource
+import com.google.samples.apps.nowinandroid.core.ui.FollowedTopicsState
 import com.google.samples.apps.nowinandroid.core.ui.NewsFeedUiState
 import dagger.hilt.android.lifecycle.HiltViewModel
 import javax.inject.Inject
@@ -42,7 +44,7 @@ class ForYouViewModel @Inject constructor(
     syncStatusMonitor: SyncStatusMonitor,
     private val userDataRepository: UserDataRepository,
     private val getSaveableNewsResources: GetSaveableNewsResourcesUseCase,
-    getFollowableTopics: GetFollowableTopicsUseCase
+    private val getFollowableTopics: GetFollowableTopicsUseCase
 ) : ViewModel() {
 
     private val shouldShowOnboarding: Flow<Boolean> =
@@ -55,6 +57,15 @@ class ForYouViewModel @Inject constructor(
             initialValue = false
         )
 
+    val followedTopicsState: StateFlow<FollowedTopicsState> =
+        getFollowableTopics().map(
+            FollowedTopicsState::Topics
+        ).stateIn(
+            scope = viewModelScope,
+            started = SharingStarted.WhileSubscribed(5_000),
+            initialValue = FollowedTopicsState.Loading
+        )
+
     val feedState: StateFlow<NewsFeedUiState> =
         userDataRepository.userData
             .map { userData ->