fix: update last read message on conversation opening [WPB-7208]

app/src/main/kotlin/com/wire/android/ui/home/conversations/ConversationScreen.kt

@@ -887,6 +887,7 @@ private fun SnackBarMessage(
     }
 }
 
+@Suppress("ComplexMethod")
 @SuppressLint("UnusedMaterial3ScaffoldPaddingParameter")
 @Composable
 fun MessageList(
@@ -914,6 +915,8 @@ fun MessageList(
     interactionAvailability: InteractionAvailability,
 ) {
     val prevItemCount = remember { mutableStateOf(lazyPagingMessages.itemCount) }
+    val readLastMessageAtStartTriggered = remember { mutableStateOf(false) }
+
     LaunchedEffect(lazyPagingMessages.itemCount) {
         if (lazyPagingMessages.itemCount > prevItemCount.value && selectedMessageId == null) {
             val canScrollToLastMessage = prevItemCount.value > 0
@@ -926,17 +929,20 @@ fun MessageList(
         }
     }
 
+    // update last read message when scroll ends
     LaunchedEffect(lazyListState.isScrollInProgress) {
         if (!lazyListState.isScrollInProgress && lazyPagingMessages.itemCount > 0) {
             val lastVisibleMessage = lazyPagingMessages[lazyListState.firstVisibleItemIndex] ?: return@LaunchedEffect
+            updateLastReadMessage(lastVisibleMessage, lastUnreadMessageInstant, onUpdateConversationReadDate)
+        }
+    }
 
-            val lastVisibleMessageInstant = Instant.parse(lastVisibleMessage.header.messageTime.utcISO)
-
-            // TODO: This IF condition should be in the UseCase
-            //       If there are no unread messages, then use distant future and don't update read date
-            if (lastVisibleMessageInstant > (lastUnreadMessageInstant ?: Instant.DISTANT_FUTURE)) {
-                onUpdateConversationReadDate(lastVisibleMessage.header.messageTime.utcISO)
-            }
+    // update last read message on start
+    LaunchedEffect(lazyPagingMessages.itemCount) {
+        if (!readLastMessageAtStartTriggered.value && lazyPagingMessages.itemSnapshotList.items.isNotEmpty()) {
+            val lastVisibleMessage = lazyPagingMessages[lazyListState.firstVisibleItemIndex] ?: return@LaunchedEffect
+            readLastMessageAtStartTriggered.value = true
+            updateLastReadMessage(lastVisibleMessage, lastUnreadMessageInstant, onUpdateConversationReadDate)
         }
     }
 
@@ -1023,6 +1029,20 @@ fun MessageList(
         })
 }
 
+private fun updateLastReadMessage(
+    lastVisibleMessage: UIMessage,
+    lastUnreadMessageInstant: Instant?,
+    onUpdateConversationReadDate: (String) -> Unit
+) {
+    val lastVisibleMessageInstant = Instant.parse(lastVisibleMessage.header.messageTime.utcISO)
+
+    // TODO: This IF condition should be in the UseCase
+    //       If there are no unread messages, then use distant future and don't update read date
+    if (lastVisibleMessageInstant > (lastUnreadMessageInstant ?: Instant.DISTANT_FUTURE)) {
+        onUpdateConversationReadDate(lastVisibleMessage.header.messageTime.utcISO)
+    }
+}
+
 @Composable
 fun JumpToLastMessageButton(
     coroutineScope: CoroutineScope = rememberCoroutineScope(),