action_sheet: Implement resolve/unresolve in topic action sheet

Fixes: zulip#744

assets/l10n/app_en.arb

@@ -92,6 +92,22 @@
   "@actionSheetOptionUnfollowTopic":  {
     "description": "Label for unfollowing a topic on action sheet."
   },
+  "actionSheetOptionResolveTopic": "Mark as resolved",
+  "@actionSheetOptionResolveTopic": {
+    "description": "Label for the 'Mark as resolved' button on the topic action sheet."
+  },
+  "actionSheetOptionUnresolveTopic": "Mark as unresolved",
+  "@actionSheetOptionUnresolveTopic": {
+    "description": "Label for the 'Mark as unresolved' button on the topic action sheet."
+  },
+  "errorResolveTopicFailedTitle": "Failed to mark topic as resolved",
+  "@errorResolveTopicFailedTitle": {
+    "description": "Error title when marking a topic as resolved failed."
+  },
+  "errorUnresolveTopicFailedTitle": "Failed to mark topic as unresolved",
+  "@errorUnresolveTopicFailedTitle": {
+    "description": "Error title when marking a topic as unresolved failed."
+  },
   "actionSheetOptionCopyMessageText": "Copy message text",
   "@actionSheetOptionCopyMessageText":  {
     "description": "Label for copy message text button on action sheet."

lib/api/model/model.dart

@@ -695,6 +695,12 @@ extension type const TopicName(String _value) {
   /// The key to use for "same topic as" comparisons.
   String canonicalize() => apiName.toLowerCase();
 
+  /// Whether the topic starts with [resolvedTopicPrefix].
+  bool get isResolved => _value.startsWith(resolvedTopicPrefix);
+
+  /// This [TopicName] plus the [resolvedTopicPrefix] prefix.
+  TopicName resolve() => TopicName(resolvedTopicPrefix + _value);
+
   /// A [TopicName] with [resolvedTopicPrefixRegexp] stripped if present.
   TopicName unresolve() =>
     TopicName(_value.replaceFirst(resolvedTopicPrefixRegexp, ''));

lib/generated/l10n/zulip_localizations.dart

@@ -243,6 +243,30 @@ abstract class ZulipLocalizations {
   /// **'Unfollow topic'**
   String get actionSheetOptionUnfollowTopic;
 
+  /// Label for the 'Mark as resolved' button on the topic action sheet.
+  ///
+  /// In en, this message translates to:
+  /// **'Mark as resolved'**
+  String get actionSheetOptionResolveTopic;
+
+  /// Label for the 'Mark as unresolved' button on the topic action sheet.
+  ///
+  /// In en, this message translates to:
+  /// **'Mark as unresolved'**
+  String get actionSheetOptionUnresolveTopic;
+
+  /// Error title when marking a topic as resolved failed.
+  ///
+  /// In en, this message translates to:
+  /// **'Failed to mark topic as resolved'**
+  String get errorResolveTopicFailedTitle;
+
+  /// Error title when marking a topic as unresolved failed.
+  ///
+  /// In en, this message translates to:
+  /// **'Failed to mark topic as unresolved'**
+  String get errorUnresolveTopicFailedTitle;
+
   /// Label for copy message text button on action sheet.
   ///
   /// In en, this message translates to:

lib/generated/l10n/zulip_localizations_ar.dart

@@ -79,6 +79,18 @@ class ZulipLocalizationsAr extends ZulipLocalizations {
   @override
   String get actionSheetOptionUnfollowTopic => 'Unfollow topic';
 
+  @override
+  String get actionSheetOptionResolveTopic => 'Mark as resolved';
+
+  @override
+  String get actionSheetOptionUnresolveTopic => 'Mark as unresolved';
+
+  @override
+  String get errorResolveTopicFailedTitle => 'Failed to mark topic as resolved';
+
+  @override
+  String get errorUnresolveTopicFailedTitle => 'Failed to mark topic as unresolved';
+
   @override
   String get actionSheetOptionCopyMessageText => 'Copy message text';
 

lib/generated/l10n/zulip_localizations_en.dart

@@ -79,6 +79,18 @@ class ZulipLocalizationsEn extends ZulipLocalizations {
   @override
   String get actionSheetOptionUnfollowTopic => 'Unfollow topic';
 
+  @override
+  String get actionSheetOptionResolveTopic => 'Mark as resolved';
+
+  @override
+  String get actionSheetOptionUnresolveTopic => 'Mark as unresolved';
+
+  @override
+  String get errorResolveTopicFailedTitle => 'Failed to mark topic as resolved';
+
+  @override
+  String get errorUnresolveTopicFailedTitle => 'Failed to mark topic as unresolved';
+
   @override
   String get actionSheetOptionCopyMessageText => 'Copy message text';
 

lib/generated/l10n/zulip_localizations_ja.dart

@@ -79,6 +79,18 @@ class ZulipLocalizationsJa extends ZulipLocalizations {
   @override
   String get actionSheetOptionUnfollowTopic => 'Unfollow topic';
 
+  @override
+  String get actionSheetOptionResolveTopic => 'Mark as resolved';
+
+  @override
+  String get actionSheetOptionUnresolveTopic => 'Mark as unresolved';
+
+  @override
+  String get errorResolveTopicFailedTitle => 'Failed to mark topic as resolved';
+
+  @override
+  String get errorUnresolveTopicFailedTitle => 'Failed to mark topic as unresolved';
+
   @override
   String get actionSheetOptionCopyMessageText => 'Copy message text';
 

lib/generated/l10n/zulip_localizations_nb.dart

@@ -79,6 +79,18 @@ class ZulipLocalizationsNb extends ZulipLocalizations {
   @override
   String get actionSheetOptionUnfollowTopic => 'Unfollow topic';
 
+  @override
+  String get actionSheetOptionResolveTopic => 'Mark as resolved';
+
+  @override
+  String get actionSheetOptionUnresolveTopic => 'Mark as unresolved';
+
+  @override
+  String get errorResolveTopicFailedTitle => 'Failed to mark topic as resolved';
+
+  @override
+  String get errorUnresolveTopicFailedTitle => 'Failed to mark topic as unresolved';
+
   @override
   String get actionSheetOptionCopyMessageText => 'Copy message text';
 

lib/generated/l10n/zulip_localizations_pl.dart

@@ -79,6 +79,18 @@ class ZulipLocalizationsPl extends ZulipLocalizations {
   @override
   String get actionSheetOptionUnfollowTopic => 'Nie śledź wątku';
 
+  @override
+  String get actionSheetOptionResolveTopic => 'Mark as resolved';
+
+  @override
+  String get actionSheetOptionUnresolveTopic => 'Mark as unresolved';
+
+  @override
+  String get errorResolveTopicFailedTitle => 'Failed to mark topic as resolved';
+
+  @override
+  String get errorUnresolveTopicFailedTitle => 'Failed to mark topic as unresolved';
+
   @override
   String get actionSheetOptionCopyMessageText => 'Skopiuj tekst wiadomości';
 

lib/generated/l10n/zulip_localizations_ru.dart

@@ -79,6 +79,18 @@ class ZulipLocalizationsRu extends ZulipLocalizations {
   @override
   String get actionSheetOptionUnfollowTopic => 'Не отслеживать тему';
 
+  @override
+  String get actionSheetOptionResolveTopic => 'Mark as resolved';
+
+  @override
+  String get actionSheetOptionUnresolveTopic => 'Mark as unresolved';
+
+  @override
+  String get errorResolveTopicFailedTitle => 'Failed to mark topic as resolved';
+
+  @override
+  String get errorUnresolveTopicFailedTitle => 'Failed to mark topic as unresolved';
+
   @override
   String get actionSheetOptionCopyMessageText => 'Скопировать текст сообщения';
 

lib/generated/l10n/zulip_localizations_sk.dart

@@ -79,6 +79,18 @@ class ZulipLocalizationsSk extends ZulipLocalizations {
   @override
   String get actionSheetOptionUnfollowTopic => 'Prestať sledovať tému';
 
+  @override
+  String get actionSheetOptionResolveTopic => 'Mark as resolved';
+
+  @override
+  String get actionSheetOptionUnresolveTopic => 'Mark as unresolved';
+
+  @override
+  String get errorResolveTopicFailedTitle => 'Failed to mark topic as resolved';
+
+  @override
+  String get errorUnresolveTopicFailedTitle => 'Failed to mark topic as unresolved';
+
   @override
   String get actionSheetOptionCopyMessageText => 'Skopírovať text správy';
 

lib/widgets/action_sheet.dart

@@ -166,9 +166,13 @@ class ActionSheetCancelButton extends StatelessWidget {
 /// Show a sheet of actions you can take on a topic.
 ///
 /// Needs a [PageRoot] ancestor.
+///
+/// The API request for resolving/unresolving a topic needs a message ID.
+/// If [someMessageIdInTopic] is null, the button for that will be absent.
 void showTopicActionSheet(BuildContext context, {
   required int channelId,
   required TopicName topic,
+  required int? someMessageIdInTopic,
 }) {
   final pageContext = PageRoot.contextOf(context);
 
@@ -245,6 +249,12 @@ void showTopicActionSheet(BuildContext context, {
       pageContext: pageContext);
   }));
 
+  if (someMessageIdInTopic != null) {
+    optionButtons.add(ResolveUnresolveButton(pageContext: pageContext,
+      topic: topic,
+      someMessageIdInTopic: someMessageIdInTopic));
+  }
+
   if (optionButtons.isEmpty) {
     // TODO(a11y): This case makes a no-op gesture handler; as a consequence,
     //   we're presenting some UI (to people who use screen-reader software) as
@@ -377,6 +387,80 @@ class UserTopicUpdateButton extends ActionSheetMenuItemButton {
   }
 }
 
+class ResolveUnresolveButton extends ActionSheetMenuItemButton {
+  ResolveUnresolveButton({
+    super.key,
+    required this.topic,
+    required this.someMessageIdInTopic,
+    required super.pageContext,
+  }) : _actionIsResolve = !topic.isResolved;
+
+  /// The topic that the action sheet was opened for.
+  ///
+  /// There might not currently be any messages with this topic;
+  /// see dartdoc of [ActionSheetMenuItemButton].
+  final TopicName topic;
+
+  /// The message ID that was passed when opening the action sheet.
+  ///
+  /// The message with this ID might currently not exist,
+  /// or might exist with a different topic;
+  /// see dartdoc of [ActionSheetMenuItemButton].
+  final int someMessageIdInTopic;
+
+  final bool _actionIsResolve;
+
+  @override
+  IconData get icon => _actionIsResolve ? ZulipIcons.check : ZulipIcons.check_remove;
+
+  @override
+  String label(ZulipLocalizations zulipLocalizations) {
+    return _actionIsResolve
+      ? zulipLocalizations.actionSheetOptionResolveTopic
+      : zulipLocalizations.actionSheetOptionUnresolveTopic;
+  }
+
+  @override void onPressed() async {
+    final zulipLocalizations = ZulipLocalizations.of(pageContext);
+    final store = PerAccountStoreWidget.of(pageContext);
+
+    // We *could* check here if the topic has changed since the action sheet was
+    // opened (see dartdoc of [ActionSheetMenuItemButton]) and abort if so.
+    // We simplify by not doing so.
+    // There's already an inherent race that that check wouldn't help with:
+    // when you tap the button, an intervening topic change may already have
+    // happened, just not reached us in an event yet.
+    // Discussion, including about what web does:
+    //   https://github.com/zulip/zulip-flutter/pull/1301#discussion_r1936181560
+
+    try {
+      await updateMessage(store.connection,
+        messageId: someMessageIdInTopic,
+        topic: _actionIsResolve ? topic.resolve() : topic.unresolve(),
+        propagateMode: PropagateMode.changeAll,
+        sendNotificationToOldThread: false,
+        sendNotificationToNewThread: true,
+      );
+    } catch (e) {
+      if (!pageContext.mounted) return;
+
+      String? errorMessage;
+      switch (e) {
+        case ZulipApiException():
+          errorMessage = e.message;
+          // TODO(#741) specific messages for common errors, like network errors
+          //   (support with reusable code)
+        default:
+      }
+
+      final title = _actionIsResolve
+        ? zulipLocalizations.errorResolveTopicFailedTitle
+        : zulipLocalizations.errorUnresolveTopicFailedTitle;
+      showErrorDialog(context: pageContext, title: title, message: errorMessage);
+    }
+  }
+}
+
 /// Show a sheet of actions you can take on a message in the message list.
 ///
 /// Must have a [MessageListPage] ancestor.

lib/widgets/inbox.dart

@@ -507,7 +507,8 @@ class _TopicItem extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    final _StreamSectionTopicData(:topic, :count, :hasMention) = data;
+    final _StreamSectionTopicData(
+      :topic, :count, :hasMention, :lastUnreadId) = data;
 
     final store = PerAccountStoreWidget.of(context);
     final subscription = store.subscriptions[streamId]!;
@@ -525,7 +526,9 @@ class _TopicItem extends StatelessWidget {
             MessageListPage.buildRoute(context: context, narrow: narrow));
         },
         onLongPress: () => showTopicActionSheet(context,
-          channelId: streamId, topic: topic),
+          channelId: streamId,
+          topic: topic,
+          someMessageIdInTopic: lastUnreadId),
         child: ConstrainedBox(constraints: const BoxConstraints(minHeight: 34),
           child: Row(crossAxisAlignment: CrossAxisAlignment.center, children: [
             const SizedBox(width: 63),

lib/widgets/message_list.dart

@@ -404,8 +404,20 @@ class MessageListAppBarTitle extends StatelessWidget {
           width: double.infinity,
           child: GestureDetector(
             behavior: HitTestBehavior.translucent,
-            onLongPress: () => showTopicActionSheet(context,
-              channelId: streamId, topic: topic),
+            onLongPress: () {
+              final someMessage = MessageListPage.ancestorOf(context)
+                .model?.messages.firstOrNull;
+              // If someMessage is null, the topic action sheet won't have a
+              // resolve/unresolve button. That seems OK; in that case we're
+              // either still fetching messages (and the user can reopen the
+              // sheet after that finishes) or there aren't any messages to
+              // act on anyway.
+              assert(someMessage == null || narrow.containsMessage(someMessage));
+              showTopicActionSheet(context,
+                channelId: streamId,
+                topic: topic,
+                someMessageIdInTopic: someMessage?.id);
+            },
             child: Column(
               crossAxisAlignment: willCenterTitle ? CrossAxisAlignment.center
                                                   : CrossAxisAlignment.start,
@@ -1127,7 +1139,9 @@ class StreamMessageRecipientHeader extends StatelessWidget {
             MessageListPage.buildRoute(context: context,
               narrow: TopicNarrow.ofMessage(message))),
       onLongPress: () => showTopicActionSheet(context,
-        channelId: message.streamId, topic: topic),
+        channelId: message.streamId,
+        topic: topic,
+        someMessageIdInTopic: message.id),
       child: ColoredBox(
         color: backgroundColor,
         child: Row(