From 2350e93db33d18f247491f9ba635c4e16a7c56e1 Mon Sep 17 00:00:00 2001
From: Nuno Vieira <nuno.fcvieira93@gmail.com>
Date: Fri, 6 Dec 2024 16:14:04 +0000
Subject: [PATCH] Fix message thread reply footnote view not shown if parent
 message not in cache (#681)

* First solution: Provide the reply in the parentMessage parameter and do workaround

* Revert "First solution: Provide the reply in the parentMessage parameter and do workaround"

This reverts commit cfb4b2ed9eeee59c066a54f47577e5c17b52f097.

* Final solution: Create a Lazy view that waits for the parent message to be fetched

This solution requires the least amount of changes and there is also no breaking change

* Update CHANGELOG.md

* Remove unused properties

* PR feedback

* Fix Xcode 15

* Fix Xcode 15

* Use on appear instead

* Please....
---
 CHANGELOG.md                                  |  2 +
 .../MessageList/MessageContainerView.swift    | 14 +++++++
 .../MessageList/MessageRepliesView.swift      | 42 +++++++++++++++++++
 3 files changed, 58 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 83acba62..8cf27ff8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 # Upcoming
 
+### 🐞 Fixed
+- Fix message thread reply footnote view not shown if parent message not in cache [#681](https://github.com/GetStream/stream-chat-swiftui/pull/681)
 ### ⚡ Performance
 - Improve message search performance [#680](https://github.com/GetStream/stream-chat-swiftui/pull/680)
 
diff --git a/Sources/StreamChatSwiftUI/ChatChannel/MessageList/MessageContainerView.swift b/Sources/StreamChatSwiftUI/ChatChannel/MessageList/MessageContainerView.swift
index ea39a48d..594fb3bf 100644
--- a/Sources/StreamChatSwiftUI/ChatChannel/MessageList/MessageContainerView.swift
+++ b/Sources/StreamChatSwiftUI/ChatChannel/MessageList/MessageContainerView.swift
@@ -185,6 +185,20 @@ public struct MessageContainerView<Factory: ViewFactory>: View {
                             )
                             .accessibilityElement(children: .contain)
                             .accessibility(identifier: "MessageRepliesView")
+                        } else if message.showReplyInChannel, let parentId = message.parentMessageId {
+                            /// In case the parent message is not available in the local cache, we need to fetch it from the remote server.
+                            /// The lazy view uses the `factory.makeMessageRepliesShownInChannelView` internally once the parent message is fetched.
+                            LazyMessageRepliesView(
+                                factory: factory,
+                                channel: channel,
+                                message: message,
+                                parentMessageController: chatClient.messageController(
+                                    cid: channel.cid,
+                                    messageId: parentId
+                                )
+                            )
+                            .accessibilityElement(children: .contain)
+                            .accessibility(identifier: "MessageRepliesView")
                         }
                     }
                     
diff --git a/Sources/StreamChatSwiftUI/ChatChannel/MessageList/MessageRepliesView.swift b/Sources/StreamChatSwiftUI/ChatChannel/MessageList/MessageRepliesView.swift
index 8aec642c..69dcd7ab 100644
--- a/Sources/StreamChatSwiftUI/ChatChannel/MessageList/MessageRepliesView.swift
+++ b/Sources/StreamChatSwiftUI/ChatChannel/MessageList/MessageRepliesView.swift
@@ -116,3 +116,45 @@ public struct MessageRepliesView<Factory: ViewFactory>: View {
         }
     }
 }
+
+/// Lazy view that uses the message controller to fetch the parent message before creating message replies view.
+/// This is needed when the parent message is not available in the local cache.
+/// Changing the `parentMessage` to `nil` in the `MessageRepliesView` would case multiple changes including breaking changes.
+struct LazyMessageRepliesView<Factory: ViewFactory>: View {
+    @StateObject private var parentMessageObserver: ChatMessageController.ObservableObject
+
+    var factory: Factory
+    var channel: ChatChannel
+    var message: ChatMessage
+
+    init(
+        factory: Factory,
+        channel: ChatChannel,
+        message: ChatMessage,
+        parentMessageController: ChatMessageController
+    ) {
+        _parentMessageObserver = StateObject(wrappedValue: parentMessageController.observableObject)
+        self.factory = factory
+        self.channel = channel
+        self.message = message
+    }
+
+    var body: some View {
+        VStack {
+            if let parentMessage = parentMessageObserver.message {
+                factory.makeMessageRepliesShownInChannelView(
+                    channel: channel,
+                    message: message,
+                    parentMessage: parentMessage,
+                    replyCount: parentMessage.replyCount
+                )
+            } else {
+                EmptyView()
+            }
+        }.onAppear {
+            if parentMessageObserver.message == nil {
+                parentMessageObserver.controller.synchronize()
+            }
+        }
+    }
+}