From 6463af83a32b1e26bad60ac946120e8f1a26da4b Mon Sep 17 00:00:00 2001
From: ganfra <francoisg@matrix.org>
Date: Tue, 1 Oct 2024 23:01:40 +0200
Subject: [PATCH] timeline : do not call focusOnLive too soon #2

---
 .../impl/timeline/TimelineController.kt       |  5 ++--
 .../impl/timeline/TimelinePresenter.kt        | 24 +++++++++++++------
 2 files changed, 20 insertions(+), 9 deletions(-)

diff --git a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/timeline/TimelineController.kt b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/timeline/TimelineController.kt
index bb64e58212..7354f2bedc 100644
--- a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/timeline/TimelineController.kt
+++ b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/timeline/TimelineController.kt
@@ -57,8 +57,9 @@ class TimelineController @Inject constructor(
         return detachedTimeline.map { !it.isPresent }
     }
 
-    fun currentPaginationStatus(direction: Timeline.PaginationDirection): Timeline.PaginationStatus {
-        return currentTimelineFlow.value.paginationStatus(direction).value
+    @OptIn(ExperimentalCoroutinesApi::class)
+    fun paginationStatus(direction: Timeline.PaginationDirection): Flow<Timeline.PaginationStatus> {
+        return currentTimelineFlow.flatMapLatest { timeline -> timeline.paginationStatus(direction)}
     }
 
     suspend fun invokeOnCurrentTimeline(block: suspend (Timeline.() -> Any)) {
diff --git a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/timeline/TimelinePresenter.kt b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/timeline/TimelinePresenter.kt
index 2989701c9f..ad1ce919fe 100644
--- a/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/timeline/TimelinePresenter.kt
+++ b/features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/timeline/TimelinePresenter.kt
@@ -53,6 +53,7 @@ import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.combine
 import kotlinx.coroutines.flow.launchIn
+import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.flow.onEach
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
@@ -130,6 +131,8 @@ class TimelinePresenter @AssistedInject constructor(
         val renderReadReceipts by sessionPreferencesStore.isRenderReadReceiptsEnabled().collectAsState(initial = true)
         val isLive by timelineController.isLive().collectAsState(initial = true)
 
+        var shouldFocusOnLive by rememberSaveable { mutableStateOf(false) }
+
         fun handleEvents(event: TimelineEvents) {
             when (event) {
                 is TimelineEvents.LoadMore -> {
@@ -142,7 +145,7 @@ class TimelinePresenter @AssistedInject constructor(
                         if (event.firstIndex == 0) {
                             newEventState.value = NewEventState.None
                         }
-                        println("## sendReadReceiptIfNeeded firstVisibleIndex: ${event.firstIndex}")
+                        shouldFocusOnLive = false
                         appScope.sendReadReceiptIfNeeded(
                             firstVisibleIndex = event.firstIndex,
                             timelineItems = timelineItems,
@@ -151,12 +154,7 @@ class TimelinePresenter @AssistedInject constructor(
                         )
                     } else {
                         newEventState.value = NewEventState.None
-                        if (event.firstIndex == 0) {
-                            val forwardPaginationStatus = timelineController.currentPaginationStatus(Timeline.PaginationDirection.FORWARDS)
-                            if (!forwardPaginationStatus.hasMoreToLoad) {
-                                timelineController.focusOnLive()
-                            }
-                        }
+                        shouldFocusOnLive = event.firstIndex == 0
                     }
                 }
                 is TimelineEvents.SelectPollAnswer -> appScope.launch {
@@ -193,6 +191,18 @@ class TimelinePresenter @AssistedInject constructor(
             }
         }
 
+        val hasMoreToLoadForward by remember {
+            timelineController
+                .paginationStatus(Timeline.PaginationDirection.FORWARDS)
+                .map { it.hasMoreToLoad }
+        }.collectAsState(false)
+
+        LaunchedEffect(shouldFocusOnLive, hasMoreToLoadForward) {
+            if (shouldFocusOnLive && !hasMoreToLoadForward) {
+                timelineController.focusOnLive()
+            }
+        }
+
         LaunchedEffect(focusRequestState) {
             when (val currentFocusRequestState = focusRequestState) {
                 is FocusRequestState.Requested -> {