fix(core): Channel doesn't auto display again after being hidden.

Signed-off-by: xsahil03x <xdsahil@gmail.com>

packages/stream_chat_flutter_core/CHANGELOG.md

@@ -1,3 +1,8 @@
+## Upcoming
+
+- [[#1356]](https://github.com/GetStream/stream-chat-flutter/issues/1356) Channel doesn't auto display again after being
+  hidden.
+
 ## 6.0.0
 
 - Updated dependencies to resolvable versions.

packages/stream_chat_flutter_core/lib/src/stream_channel.dart

@@ -387,12 +387,20 @@ class StreamChannelState extends State<StreamChannel> {
         (it) => it.user.id == channel.client.state.currentUser?.id,
       );
 
-      if (read != null &&
-          !(channel.state!.messages
-                  .any((it) => it.createdAt.compareTo(read.lastRead) > 0) &&
-              channel.state!.messages
-                  .any((it) => it.createdAt.compareTo(read.lastRead) <= 0))) {
-        _futures.add(_loadChannelAtTimestamp(read.lastRead));
+      if (read == null) return;
+
+      final messages = channel.state!.messages;
+      final lastRead = read.lastRead;
+
+      final hasNewMessages =
+          messages.any((it) => it.createdAt.isAfter(lastRead));
+      final hasOldMessages =
+          messages.any((it) => it.createdAt.isBeforeOrEqualTo(lastRead));
+
+      // Only load messages if the unread message is in-between the messages.
+      // Otherwise, we can just load the channel normally.
+      if (hasNewMessages && hasOldMessages) {
+        _futures.add(_loadChannelAtTimestamp(lastRead));
       }
     }
   }
@@ -449,3 +457,9 @@ class StreamChannelState extends State<StreamChannel> {
     return child;
   }
 }
+
+extension on DateTime {
+  bool isBeforeOrEqualTo(DateTime other) {
+    return isBefore(other) || isAtSameMomentAs(other);
+  }
+}

packages/stream_chat_flutter_core/lib/src/stream_channel_list_event_handler.dart

@@ -101,14 +101,19 @@ class StreamChannelListEventHandler {
   /// we are currently watching.
   ///
   /// By default, this moves the channel to the top of the list.
-  void onMessageNew(Event event, StreamChannelListController controller) {
+  void onMessageNew(Event event, StreamChannelListController controller) async {
     final channelCid = event.cid;
     if (channelCid == null) return;
 
     final channels = [...controller.currentItems];
 
     final channelIndex = channels.indexWhere((it) => it.cid == channelCid);
-    if (channelIndex <= 0) return;
+    if (channelIndex <= 0) {
+      // If the channel is not in the list, It might be hidden.
+      // So, we just refresh the list.
+      await controller.refresh(resetValue: false);
+      return;
+    }
 
     final channel = channels.removeAt(channelIndex);
     channels.insert(0, channel);