Display number of comments

app/src/main/java/org/schabi/newpipe/paging/CommentsSource.kt

@@ -8,13 +8,19 @@ import org.schabi.newpipe.extractor.NewPipe
 import org.schabi.newpipe.extractor.Page
 import org.schabi.newpipe.extractor.comments.CommentsInfo
 import org.schabi.newpipe.extractor.comments.CommentsInfoItem
+import org.schabi.newpipe.ui.components.video.comment.CommentInfo
 import org.schabi.newpipe.util.NO_SERVICE_ID
 
 class CommentsSource(
     serviceId: Int,
-    private val url: String?,
+    private val url: String,
-    private val repliesPage: Page?
+    private val repliesPage: Page?,
+    private val commentInfo: CommentInfo? = null,
 ) : PagingSource<Page, CommentsInfoItem>() {
+    constructor(commentInfo: CommentInfo) : this(
+        commentInfo.serviceId, commentInfo.url, commentInfo.nextPage, commentInfo
+    )
+
     init {
         require(serviceId != NO_SERVICE_ID) { "serviceId is NO_SERVICE_ID" }
     }
@@ -29,17 +35,11 @@ class CommentsSource(
                 val info = CommentsInfo.getMoreItems(service, url, it)
                 LoadResult.Page(info.items, null, info.nextPage)
             } ?: run {
-                val info = CommentsInfo.getInfo(service, url)
+                val info = commentInfo ?: CommentInfo(CommentsInfo.getInfo(service, url))
-                if (info.isCommentsDisabled) {
+                LoadResult.Page(info.comments, null, info.nextPage)
-                    LoadResult.Error(CommentsDisabledException())
-                } else {
-                    LoadResult.Page(info.relatedItems, null, info.nextPage)
-                }
             }
         }
     }
 
     override fun getRefreshKey(state: PagingState<Page, CommentsInfoItem>) = null
 }
-
-class CommentsDisabledException : RuntimeException()

app/src/main/java/org/schabi/newpipe/ui/components/video/comment/Comment.kt

@@ -166,7 +166,13 @@ fun Comment(comment: CommentsInfoItem) {
                     .cachedIn(coroutineScope)
             }
 
-            CommentSection(parentComment = comment, commentsFlow = flow)
+            Surface(color = MaterialTheme.colorScheme.background) {
+                CommentSection(
+                    commentsFlow = flow,
+                    commentCount = comment.replyCount,
+                    parentComment = comment
+                )
+            }
         }
     }
 }

app/src/main/java/org/schabi/newpipe/ui/components/video/comment/CommentInfo.kt

@@ -0,0 +1,21 @@
+package org.schabi.newpipe.ui.components.video.comment
+
+import androidx.compose.runtime.Immutable
+import org.schabi.newpipe.extractor.Page
+import org.schabi.newpipe.extractor.comments.CommentsInfo
+import org.schabi.newpipe.extractor.comments.CommentsInfoItem
+
+@Immutable
+class CommentInfo(
+    val serviceId: Int,
+    val url: String,
+    val comments: List<CommentsInfoItem>,
+    val nextPage: Page?,
+    val commentCount: Int,
+    val isCommentsDisabled: Boolean
+) {
+    constructor(commentsInfo: CommentsInfo) : this(
+        commentsInfo.serviceId, commentsInfo.url, commentsInfo.relatedItems, commentsInfo.nextPage,
+        commentsInfo.commentsCount, commentsInfo.isCommentsDisabled
+    )
+}

app/src/main/java/org/schabi/newpipe/ui/components/video/comment/CommentSection.kt

@@ -7,20 +7,19 @@ import androidx.compose.foundation.lazy.rememberLazyListState
 import androidx.compose.material3.HorizontalDivider
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Surface
+import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
-import androidx.compose.runtime.derivedStateOf
 import androidx.compose.runtime.getValue
-import androidx.compose.runtime.remember
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.input.nestedscroll.nestedScroll
 import androidx.compose.ui.platform.rememberNestedScrollInteropConnection
+import androidx.compose.ui.res.pluralStringResource
+import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.tooling.preview.Preview
-import androidx.compose.ui.tooling.preview.PreviewParameter
-import androidx.compose.ui.tooling.preview.PreviewParameterProvider
 import androidx.compose.ui.unit.dp
+import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import androidx.lifecycle.viewmodel.compose.viewModel
 import androidx.paging.LoadState
-import androidx.paging.LoadStates
 import androidx.paging.PagingData
 import androidx.paging.compose.collectAsLazyPagingItems
 import kotlinx.coroutines.flow.Flow
@@ -30,106 +29,157 @@ import org.schabi.newpipe.R
 import org.schabi.newpipe.extractor.Page
 import org.schabi.newpipe.extractor.comments.CommentsInfoItem
 import org.schabi.newpipe.extractor.stream.Description
-import org.schabi.newpipe.paging.CommentsDisabledException
 import org.schabi.newpipe.ui.components.common.LoadingIndicator
 import org.schabi.newpipe.ui.components.common.NoItemsMessage
 import org.schabi.newpipe.ui.theme.AppTheme
 import org.schabi.newpipe.viewmodels.CommentsViewModel
+import org.schabi.newpipe.viewmodels.util.Resource
 
 @Composable
 fun CommentSection(commentsViewModel: CommentsViewModel = viewModel()) {
-    CommentSection(commentsFlow = commentsViewModel.comments)
+    Surface(color = MaterialTheme.colorScheme.background) {
+        val state by commentsViewModel.uiState.collectAsStateWithLifecycle()
+        CommentSection(state, commentsViewModel.comments)
+    }
+}
+
+@Composable
+private fun CommentSection(
+    uiState: Resource<CommentInfo>,
+    commentsFlow: Flow<PagingData<CommentsInfoItem>>
+) {
+    when (uiState) {
+        is Resource.Loading -> LoadingIndicator(modifier = Modifier.padding(top = 8.dp))
+
+        is Resource.Success -> {
+            val commentsInfo = uiState.data
+            CommentSection(
+                commentsFlow = commentsFlow,
+                commentCount = commentsInfo.commentCount,
+                isCommentsDisabled = commentsInfo.isCommentsDisabled
+            )
+        }
+
+        is Resource.Error -> {
+            // This is not rendered as VideoDetailFragment handles errors
+        }
+    }
 }
 
 @Composable
 fun CommentSection(
+    commentsFlow: Flow<PagingData<CommentsInfoItem>>,
+    commentCount: Int,
     parentComment: CommentsInfoItem? = null,
-    commentsFlow: Flow<PagingData<CommentsInfoItem>>
+    isCommentsDisabled: Boolean = false,
 ) {
     val comments = commentsFlow.collectAsLazyPagingItems()
-    val itemCount by remember { derivedStateOf { comments.itemCount } }
     val nestedScrollInterop = rememberNestedScrollInteropConnection()
     val state = rememberLazyListState()
 
-    Surface(color = MaterialTheme.colorScheme.background) {
+    LazyColumnScrollbar(state = state) {
-        LazyColumnScrollbar(state = state) {
+        LazyColumn(
-            LazyColumn(modifier = Modifier.nestedScroll(nestedScrollInterop), state = state) {
+            modifier = Modifier.nestedScroll(nestedScrollInterop),
-                if (parentComment != null) {
+            state = state
+        ) {
+            if (parentComment != null) {
+                item {
+                    CommentRepliesHeader(comment = parentComment)
+                    HorizontalDivider(thickness = 1.dp)
+                }
+            }
+
+            if (comments.itemCount == 0) {
+                item {
+                    val refresh = comments.loadState.refresh
+                    if (refresh is LoadState.Loading) {
+                        LoadingIndicator(modifier = Modifier.padding(top = 8.dp))
+                    } else {
+                        val message = if (refresh is LoadState.Error) {
+                            R.string.error_unable_to_load_comments
+                        } else if (isCommentsDisabled) {
+                            R.string.comments_are_disabled
+                        } else {
+                            R.string.no_comments
+                        }
+                        NoItemsMessage(message)
+                    }
+                }
+            } else {
+                // The number of replies is already shown in the main comment section
+                if (parentComment == null) {
                     item {
-                        CommentRepliesHeader(comment = parentComment)
+                        Text(
-                        HorizontalDivider(thickness = 1.dp)
+                            modifier = Modifier.padding(start = 8.dp),
+                            text = pluralStringResource(R.plurals.comments, commentCount, commentCount),
+                            fontWeight = FontWeight.Bold
+                        )
                     }
                 }
 
-                if (itemCount == 0) {
+                items(comments.itemCount) {
-                    item {
+                    Comment(comment = comments[it]!!)
-                        val refresh = comments.loadState.refresh
-                        if (refresh is LoadState.Loading) {
-                            LoadingIndicator(modifier = Modifier.padding(top = 8.dp))
-                        } else {
-                            val error = (refresh as? LoadState.Error)?.error
-                            val message = if (error is CommentsDisabledException) {
-                                R.string.comments_are_disabled
-                            } else {
-                                R.string.no_comments
-                            }
-                            NoItemsMessage(message)
-                        }
-                    }
-                } else {
-                    items(itemCount) {
-                        Comment(comment = comments[it]!!)
-                    }
                 }
             }
         }
     }
 }
 
-private class CommentDataProvider : PreviewParameterProvider<PagingData<CommentsInfoItem>> {
+@Preview(name = "Light mode", uiMode = Configuration.UI_MODE_NIGHT_NO)
-    private val notLoading = LoadState.NotLoading(true)
+@Preview(name = "Dark mode", uiMode = Configuration.UI_MODE_NIGHT_YES)
-
+@Composable
-    override val values = sequenceOf(
+private fun CommentSectionLoadingPreview() {
-        // Normal view
+    AppTheme {
-        PagingData.from(
+        Surface(color = MaterialTheme.colorScheme.background) {
-            listOf(
+            CommentSection(uiState = Resource.Loading, commentsFlow = flowOf())
-                CommentsInfoItem(
+        }
-                    commentText = Description(
+    }
-                        "Comment 1\n\nThis line should be hidden by default.",
-                        Description.PLAIN_TEXT
-                    ),
-                    uploaderName = "Test",
-                    replies = Page(""),
-                    replyCount = 10
-                )
-            ) + (2..10).map {
-                CommentsInfoItem(
-                    commentText = Description("Comment $it", Description.PLAIN_TEXT),
-                    uploaderName = "Test"
-                )
-            }
-        ),
-        // Comments disabled
-        PagingData.from(
-            listOf<CommentsInfoItem>(),
-            LoadStates(LoadState.Error(CommentsDisabledException()), notLoading, notLoading)
-        ),
-        // No comments
-        PagingData.from(
-            listOf<CommentsInfoItem>(),
-            LoadStates(notLoading, notLoading, notLoading)
-        )
-    )
 }
 
 @Preview(name = "Light mode", uiMode = Configuration.UI_MODE_NIGHT_NO)
 @Preview(name = "Dark mode", uiMode = Configuration.UI_MODE_NIGHT_YES)
 @Composable
-private fun CommentSectionPreview(
+private fun CommentSectionSuccessPreview() {
-    @PreviewParameter(CommentDataProvider::class) pagingData: PagingData<CommentsInfoItem>
+    val comments = listOf(
-) {
+        CommentsInfoItem(
+            commentText = Description(
+                "Comment 1\n\nThis line should be hidden by default.",
+                Description.PLAIN_TEXT
+            ),
+            uploaderName = "Test",
+            replies = Page(""),
+            replyCount = 10
+        )
+    ) + (2..10).map {
+        CommentsInfoItem(
+            commentText = Description("Comment $it", Description.PLAIN_TEXT),
+            uploaderName = "Test"
+        )
+    }
+
     AppTheme {
-        CommentSection(commentsFlow = flowOf(pagingData))
+        Surface(color = MaterialTheme.colorScheme.background) {
+            CommentSection(
+                uiState = Resource.Success(
+                    CommentInfo(
+                        serviceId = 1, url = "", comments = comments, nextPage = null,
+                        commentCount = 10, isCommentsDisabled = false
+                    )
+                ),
+                commentsFlow = flowOf(PagingData.from(comments))
+            )
+        }
+    }
+}
+
+@Preview(name = "Light mode", uiMode = Configuration.UI_MODE_NIGHT_NO)
+@Preview(name = "Dark mode", uiMode = Configuration.UI_MODE_NIGHT_YES)
+@Composable
+private fun CommentSectionErrorPreview() {
+    AppTheme {
+        Surface(color = MaterialTheme.colorScheme.background) {
+            CommentSection(uiState = Resource.Error(RuntimeException()), commentsFlow = flowOf())
+        }
     }
 }
 
@@ -153,6 +203,8 @@ private fun CommentRepliesPreview() {
     val flow = flowOf(PagingData.from(replies))
 
     AppTheme {
-        CommentSection(parentComment = comment, commentsFlow = flow)
+        Surface(color = MaterialTheme.colorScheme.background) {
+            CommentSection(parentComment = comment, commentsFlow = flow, commentCount = 10)
+        }
     }
 }

app/src/main/java/org/schabi/newpipe/viewmodels/CommentsViewModel.kt

@@ -6,17 +6,39 @@ import androidx.lifecycle.viewModelScope
 import androidx.paging.Pager
 import androidx.paging.PagingConfig
 import androidx.paging.cachedIn
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.flow.SharingStarted
+import kotlinx.coroutines.flow.filterIsInstance
+import kotlinx.coroutines.flow.flatMapLatest
+import kotlinx.coroutines.flow.flowOn
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.flow.stateIn
+import org.schabi.newpipe.extractor.comments.CommentsInfo
 import org.schabi.newpipe.paging.CommentsSource
-import org.schabi.newpipe.util.KEY_SERVICE_ID
+import org.schabi.newpipe.ui.components.video.comment.CommentInfo
 import org.schabi.newpipe.util.KEY_URL
-import org.schabi.newpipe.util.NO_SERVICE_ID
+import org.schabi.newpipe.viewmodels.util.Resource
 
 class CommentsViewModel(savedStateHandle: SavedStateHandle) : ViewModel() {
-    private val serviceId = savedStateHandle[KEY_SERVICE_ID] ?: NO_SERVICE_ID
+    val uiState = savedStateHandle.getStateFlow(KEY_URL, "")
-    private val url = savedStateHandle.get<String>(KEY_URL)
+        .map {
+            try {
+                Resource.Success(CommentInfo(CommentsInfo.getInfo(it)))
+            } catch (e: Exception) {
+                Resource.Error(e)
+            }
+        }
+        .flowOn(Dispatchers.IO)
+        .stateIn(viewModelScope, SharingStarted.WhileSubscribed(), Resource.Loading)
 
-    val comments = Pager(PagingConfig(pageSize = 20, enablePlaceholders = false)) {
+    @OptIn(ExperimentalCoroutinesApi::class)
-        CommentsSource(serviceId, url, null)
+    val comments = uiState
-    }.flow
+        .filterIsInstance<Resource.Success<CommentInfo>>()
+        .flatMapLatest {
+            Pager(PagingConfig(pageSize = 20, enablePlaceholders = false)) {
+                CommentsSource(it.data)
+            }.flow
+        }
         .cachedIn(viewModelScope)
 }

app/src/main/java/org/schabi/newpipe/viewmodels/util/Resource.kt

@@ -0,0 +1,7 @@
+package org.schabi.newpipe.viewmodels.util
+
+sealed class Resource<out T> {
+    data object Loading : Resource<Nothing>()
+    class Success<T>(val data: T) : Resource<T>()
+    class Error(val throwable: Throwable) : Resource<Nothing>()
+}

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

@@ -856,4 +856,8 @@
     <string name="show_less">Show less</string>
     <string name="import_settings_vulnerable_format">The settings in the export being imported use a vulnerable format that was deprecated since NewPipe 0.27.0. Make sure the export being imported is from a trusted source, and prefer using only exports obtained from NewPipe 0.27.0 or newer in the future. Support for importing settings in this vulnerable format will soon be removed completely, and then old versions of NewPipe will not be able to import settings of exports from new versions anymore.</string>
     <string name="auto_queue_description">Next</string>
+    <plurals name="comments">
+        <item quantity="one">%d comment</item>
+        <item quantity="other">%d comments</item>
+    </plurals>
 </resources>