feat: Can't collapse single message

Author: Matthieu-dgl

Mail/Views/Thread/Message/MessageView.swift

@@ -41,6 +41,8 @@ struct MessageView: View {
 
     @ObservedRealmObject var message: Message
 
+    private let isSingleMessage: Bool
+
     private var isRemoteContentBlocked: Bool {
         return (UserDefaults.shared.displayExternalContent == .askMe || message.folder?.role == .spam)
             && !message.localSafeDisplay
@@ -50,13 +52,20 @@ struct MessageView: View {
         threadForcedExpansion[message.uid] == .expanded
     }
 
+    init(threadForcedExpansion: Binding<[String: MessageExpansionType]>, message: Message, isSingleMessage: Bool) {
+        _threadForcedExpansion = threadForcedExpansion
+        self.message = message
+        self.isSingleMessage = isSingleMessage
+    }
+
     var body: some View {
         VStack(spacing: 0) {
             MessageHeaderView(
                 message: message,
                 isMessageExpanded: Binding(get: {
                     isMessageExpanded
                 }, set: { newValue in
+                    guard !isSingleMessage else { return }
                     threadForcedExpansion[message.uid] = newValue ? .expanded : .collapsed
                 })
             )
@@ -97,14 +106,16 @@ struct MessageView: View {
 #Preview("Message collapsed", traits: .sizeThatFitsLayout) {
     MessageView(
         threadForcedExpansion: .constant([PreviewHelper.sampleMessage.uid: .collapsed]),
-        message: PreviewHelper.sampleMessage
+        message: PreviewHelper.sampleMessage,
+        isSingleMessage: true
     )
 }
 
 @available(iOS 17.0, *)
 #Preview("Message expanded", traits: .sizeThatFitsLayout) {
     MessageView(
         threadForcedExpansion: .constant([PreviewHelper.sampleMessage.uid: .expanded]),
-        message: PreviewHelper.sampleMessage
+        message: PreviewHelper.sampleMessage,
+        isSingleMessage: false
     )
 }

Mail/Views/Thread/MessageListView.swift

@@ -49,7 +49,11 @@ struct MessageListView: View {
                             }
                         } else if messageExpansion[message.uid] != .superCollapsed {
                             VStack(spacing: 0) {
-                                MessageView(threadForcedExpansion: $messageExpansion, message: message)
+                                MessageView(
+                                    threadForcedExpansion: $messageExpansion,
+                                    message: message,
+                                    isSingleMessage: messages.count == 1
+                                )
                                 if divider(for: message) {
                                     IKDivider(type: .full)
                                 }

MailNotificationContentExtension/NotificationViewController.swift

@@ -93,7 +93,7 @@ class NotificationViewController: UIViewController, UNNotificationContentExtensi
 
             let messageWorker = MessagesWorker(mailboxManager: mailboxManager)
             let messageView = ScrollView {
-                MessageView(threadForcedExpansion: .constant([messageUid: .expanded]), message: message)
+                MessageView(threadForcedExpansion: .constant([messageUid: .expanded]), message: message, isSingleMessage: true)
                     .environment(\.isMessageInteractive, false)
                     .environment(\.currentUser, MandatoryEnvironmentContainer(value: currentUser))
                     .environmentObject(mailboxManager)