From 0055d9e61d28962c023c3ded4b419d0919c8acb9 Mon Sep 17 00:00:00 2001
From: Kevin Wang <kevmo314@gmail.com>
Date: Wed, 6 Jul 2022 10:57:39 -0400
Subject: [PATCH] fix: add messageId and timestamp to clear event (#544)

---
 lib/components/pinnable/scroll_view.dart |  2 +-
 lib/models/adapters/messages.dart        | 13 +++++++++++--
 lib/models/messages.dart                 |  7 ++++++-
 lib/models/messages/message.dart         |  4 +++-
 4 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/lib/components/pinnable/scroll_view.dart b/lib/components/pinnable/scroll_view.dart
index 1bfb3b580..9f9d4c6ba 100644
--- a/lib/components/pinnable/scroll_view.dart
+++ b/lib/components/pinnable/scroll_view.dart
@@ -55,7 +55,7 @@ class PinnableMessageScrollView extends ScrollView {
             (context, index) => itemBuilder(index + offset),
             findChildIndexCallback: (key) {
               final index = findChildIndexCallback(key);
-              return index == null ? null : index - offset;
+              return index == null || index == -1 ? null : index - offset;
             },
             childCount: intermediateCount,
             semanticIndexOffset: offset,
diff --git a/lib/models/adapters/messages.dart b/lib/models/adapters/messages.dart
index e8cfd5f01..b47969e45 100644
--- a/lib/models/adapters/messages.dart
+++ b/lib/models/adapters/messages.dart
@@ -36,7 +36,13 @@ class UpdateDeltaEvent extends DeltaEvent {
 }
 
 class ClearDeltaEvent extends DeltaEvent {
-  const ClearDeltaEvent();
+  final String messageId;
+  final DateTime timestamp;
+
+  const ClearDeltaEvent({
+    required this.messageId,
+    required this.timestamp,
+  });
 }
 
 DeltaEvent? _toDeltaEvent(
@@ -107,7 +113,10 @@ DeltaEvent? _toDeltaEvent(
           timestamp: data['timestamp'].toDate());
       return AppendDeltaEvent(model);
     case "clear":
-      return const ClearDeltaEvent();
+      return ClearDeltaEvent(
+        messageId: change.doc.id,
+        timestamp: data['timestamp'].toDate(),
+      );
     case "host":
       if (data['hosterChannelId'] == null) {
         // Since we might have some events saved without this field.
diff --git a/lib/models/messages.dart b/lib/models/messages.dart
index 77df9c3d0..ed67bc502 100644
--- a/lib/models/messages.dart
+++ b/lib/models/messages.dart
@@ -45,7 +45,12 @@ class MessagesModel extends ChangeNotifier {
             }
           }
         } else if (event is ClearDeltaEvent) {
-          _messages = [ChatClearedEventModel()];
+          _messages = [
+            ChatClearedEventModel(
+              messageId: event.messageId,
+              timestamp: event.timestamp,
+            )
+          ];
           _tts?.stop();
         }
         notifyListeners();
diff --git a/lib/models/messages/message.dart b/lib/models/messages/message.dart
index 0648712d7..5f4e51e4e 100644
--- a/lib/models/messages/message.dart
+++ b/lib/models/messages/message.dart
@@ -23,5 +23,7 @@ class SystemMessageModel extends MessageModel {
 }
 
 class ChatClearedEventModel extends MessageModel {
-  ChatClearedEventModel() : super(messageId: "", timestamp: DateTime.now());
+  ChatClearedEventModel(
+      {required String messageId, required DateTime timestamp})
+      : super(messageId: messageId, timestamp: timestamp);
 }