Add and handle live-updates to saved snippets data

lib/api/model/events.dart

@@ -37,6 +37,13 @@ sealed class Event {
           case 'update': return RealmUserUpdateEvent.fromJson(json);
           default: return UnexpectedEvent.fromJson(json);
         }
+      case 'saved_snippets':
+        switch (json['op'] as String) {
+          case 'add': return SavedSnippetsAddEvent.fromJson(json);
+          case 'update': return SavedSnippetsUpdateEvent.fromJson(json);
+          case 'remove': return SavedSnippetsRemoveEvent.fromJson(json);
+          default: return UnexpectedEvent.fromJson(json);
+        }
       case 'stream':
         switch (json['op'] as String) {
           case 'create': return ChannelCreateEvent.fromJson(json);
@@ -336,6 +343,71 @@ class RealmUserUpdateEvent extends RealmUserEvent {
   Map<String, dynamic> toJson() => _$RealmUserUpdateEventToJson(this);
 }
 
+/// A Zulip event of type `saved_snippets`.
+///
+/// The corresponding API docs are in several places for
+/// different values of `op`; see subclasses.
+sealed class SavedSnippetsEvent extends Event {
+  @override
+  @JsonKey(includeToJson: true)
+  String get type => 'saved_snippets';
+
+  String get op;
+
+  SavedSnippetsEvent({required super.id});
+}
+
+/// A [SavedSnippetsEvent] with op `add`: https://zulip.com/api/get-events#saved_snippets-add
+@JsonSerializable(fieldRename: FieldRename.snake)
+class SavedSnippetsAddEvent extends SavedSnippetsEvent {
+  @override
+  String get op => 'add';
+
+  final SavedSnippet savedSnippet;
+
+  SavedSnippetsAddEvent({required super.id, required this.savedSnippet});
+
+  factory SavedSnippetsAddEvent.fromJson(Map<String, dynamic> json) =>
+    _$SavedSnippetsAddEventFromJson(json);
+
+  @override
+  Map<String, dynamic> toJson() => _$SavedSnippetsAddEventToJson(this);
+}
+
+/// A [SavedSnippetsEvent] with op `update`: https://zulip.com/api/get-events#saved_snippets-update
+@JsonSerializable(fieldRename: FieldRename.snake)
+class SavedSnippetsUpdateEvent extends SavedSnippetsEvent {
+  @override
+  String get op => 'update';
+
+  final SavedSnippet savedSnippet;
+
+  SavedSnippetsUpdateEvent({required super.id, required this.savedSnippet});
+
+  factory SavedSnippetsUpdateEvent.fromJson(Map<String, dynamic> json) =>
+    _$SavedSnippetsUpdateEventFromJson(json);
+
+  @override
+  Map<String, dynamic> toJson() => _$SavedSnippetsUpdateEventToJson(this);
+}
+
+/// A [SavedSnippetsEvent] with op `remove`: https://zulip.com/api/get-events#saved_snippets-remove
+@JsonSerializable(fieldRename: FieldRename.snake)
+class SavedSnippetsRemoveEvent extends SavedSnippetsEvent {
+  @override
+  String get op => 'remove';
+
+  final int savedSnippetId;
+
+  SavedSnippetsRemoveEvent({required super.id, required this.savedSnippetId});
+
+  factory SavedSnippetsRemoveEvent.fromJson(Map<String, dynamic> json) =>
+    _$SavedSnippetsRemoveEventFromJson(json);
+
+  @override
+  Map<String, dynamic> toJson() => _$SavedSnippetsRemoveEventToJson(this);
+}
+
 /// A Zulip event of type `stream`.
 ///
 /// The corresponding API docs are in several places for

lib/api/model/initial_snapshot.dart

@@ -48,6 +48,8 @@ class InitialSnapshot {
 
   final List<RecentDmConversation> recentPrivateConversations;
 
+  final List<SavedSnippet>? savedSnippets; // TODO(server-10)
+
   final List<Subscription> subscriptions;
 
   final UnreadMessagesSnapshot unreadMsgs;
@@ -132,6 +134,7 @@ class InitialSnapshot {
     required this.serverTypingStartedWaitPeriodMilliseconds,
     required this.realmEmoji,
     required this.recentPrivateConversations,
+    required this.savedSnippets,
     required this.subscriptions,
     required this.unreadMsgs,
     required this.streams,

lib/api/model/model.dart

@@ -311,6 +311,30 @@ enum UserRole{
   }
 }
 
+/// An item in `saved_snippets` from the initial snapshot.
+///
+/// For docs, search for "saved_snippets:"
+/// in <https://zulip.com/api/register-queue>.
+@JsonSerializable(fieldRename: FieldRename.snake)
+class SavedSnippet {
+  SavedSnippet({
+    required this.id,
+    required this.title,
+    required this.content,
+    required this.dateCreated,
+  });
+
+  final int id;
+  final String title;
+  final String content;
+  final int dateCreated;
+
+  factory SavedSnippet.fromJson(Map<String, Object?> json) =>
+    _$SavedSnippetFromJson(json);
+
+  Map<String, dynamic> toJson() => _$SavedSnippetToJson(this);
+}
+
 /// As in `streams` in the initial snapshot.
 ///
 /// Not called `Stream` because dart:async uses that name.

lib/api/route/saved_snippets.dart

@@ -0,0 +1,30 @@
+import 'package:json_annotation/json_annotation.dart';
+
+import '../core.dart';
+
+part 'saved_snippets.g.dart';
+
+/// https://zulip.com/api/create-saved-snippet
+Future<CreateSavedSnippetResult> createSavedSnippet(ApiConnection connection, {
+  required String title,
+  required String content,
+}) {
+  return connection.post('createSavedSnippet', CreateSavedSnippetResult.fromJson, 'saved_snippets', {
+    'title': RawParameter(title),
+    'content': RawParameter(content),
+  });
+}
+
+@JsonSerializable(fieldRename: FieldRename.snake)
+class CreateSavedSnippetResult {
+  final int savedSnippetId;
+
+  CreateSavedSnippetResult({
+    required this.savedSnippetId,
+  });
+
+  factory CreateSavedSnippetResult.fromJson(Map<String, dynamic> json) =>
+    _$CreateSavedSnippetResultFromJson(json);
+
+  Map<String, dynamic> toJson() => _$CreateSavedSnippetResultToJson(this);
+}

lib/model/saved_snippet.dart

@@ -0,0 +1,35 @@
+import 'package:collection/collection.dart';
+
+import '../api/model/events.dart';
+import '../api/model/model.dart';
+
+mixin SavedSnippetStore {
+  Map<int, SavedSnippet> get savedSnippets;
+}
+
+class SavedSnippetStoreImpl with SavedSnippetStore {
+  SavedSnippetStoreImpl({required Iterable<SavedSnippet> savedSnippets})
+    : _savedSnippets = {
+        for (final savedSnippet in savedSnippets)
+          savedSnippet.id: savedSnippet,
+      };
+
+  @override
+  late Map<int, SavedSnippet> savedSnippets = UnmodifiableMapView(_savedSnippets);
+  final Map<int, SavedSnippet> _savedSnippets;
+
+  void handleSavedSnippetsEvent(SavedSnippetsEvent event) {
+    switch (event) {
+      case SavedSnippetsAddEvent(:final savedSnippet):
+        _savedSnippets[savedSnippet.id] = savedSnippet;
+
+      case SavedSnippetsUpdateEvent(:final savedSnippet):
+        assert(_savedSnippets[savedSnippet.id]!.dateCreated
+                 == savedSnippet.dateCreated); // TODO(log)
+        _savedSnippets[savedSnippet.id] = savedSnippet;
+
+      case SavedSnippetsRemoveEvent(:final savedSnippetId):
+        _savedSnippets.remove(savedSnippetId);
+    }
+  }
+}

lib/model/store.dart

@@ -29,6 +29,7 @@ import 'message_list.dart';
 import 'recent_dm_conversations.dart';
 import 'recent_senders.dart';
 import 'channel.dart';
+import 'saved_snippet.dart';
 import 'settings.dart';
 import 'typing_status.dart';
 import 'unreads.dart';
@@ -431,7 +432,7 @@ Uri? tryResolveUrl(Uri baseUrl, String reference) {
 /// This class does not attempt to poll an event queue
 /// to keep the data up to date.  For that behavior, see
 /// [UpdateMachine].
-class PerAccountStore extends PerAccountStoreBase with ChangeNotifier, EmojiStore, UserStore, ChannelStore, MessageStore {
+class PerAccountStore extends PerAccountStoreBase with ChangeNotifier, EmojiStore, SavedSnippetStore, UserStore, ChannelStore, MessageStore {
   /// Construct a store for the user's data, starting from the given snapshot.
   ///
   /// The global store must already have been updated with
@@ -485,6 +486,8 @@ class PerAccountStore extends PerAccountStoreBase with ChangeNotifier, EmojiStor
       emailAddressVisibility: initialSnapshot.emailAddressVisibility,
       emoji: EmojiStoreImpl(
         core: core, allRealmEmoji: initialSnapshot.realmEmoji),
+      savedSnippets: SavedSnippetStoreImpl(
+        savedSnippets: initialSnapshot.savedSnippets ?? []),
       userSettings: initialSnapshot.userSettings,
       typingNotifier: TypingNotifier(
         core: core,
@@ -523,6 +526,7 @@ class PerAccountStore extends PerAccountStoreBase with ChangeNotifier, EmojiStor
     required this.customProfileFields,
     required this.emailAddressVisibility,
     required EmojiStoreImpl emoji,
+    required SavedSnippetStoreImpl savedSnippets,
     required this.userSettings,
     required this.typingNotifier,
     required UserStoreImpl users,
@@ -534,6 +538,7 @@ class PerAccountStore extends PerAccountStoreBase with ChangeNotifier, EmojiStor
     required this.recentSenders,
   }) : _realmEmptyTopicDisplayName = realmEmptyTopicDisplayName,
        _emoji = emoji,
+       _savedSnippets = savedSnippets,
        _users = users,
        _channels = channels,
        _messages = messages;
@@ -619,6 +624,10 @@ class PerAccountStore extends PerAccountStoreBase with ChangeNotifier, EmojiStor
   ////////////////////////////////
   // Data attached to the self-account on the realm.
 
+  @override
+  Map<int, SavedSnippet> get savedSnippets => _savedSnippets.savedSnippets;
+  final SavedSnippetStoreImpl _savedSnippets;
+
   final UserSettings? userSettings; // TODO(server-5)
 
   final TypingNotifier typingNotifier;
@@ -868,6 +877,11 @@ class PerAccountStore extends PerAccountStoreBase with ChangeNotifier, EmojiStor
         autocompleteViewManager.handleRealmUserUpdateEvent(event);
         notifyListeners();
 
+      case SavedSnippetsEvent():
+        assert(debugLog('server event: saved_snippets/${event.op}'));
+        _savedSnippets.handleSavedSnippetsEvent(event);
+        notifyListeners();
+
       case ChannelEvent():
         assert(debugLog("server event: stream/${event.op}"));
         _channels.handleChannelEvent(event);

test/api/model/model_checks.dart

@@ -21,6 +21,12 @@ extension UserChecks on Subject<User> {
   Subject<bool> get isSystemBot => has((x) => x.isSystemBot, 'isSystemBot');
 }
 
+extension SavedSnippetChecks on Subject<SavedSnippet> {
+  Subject<int> get id => has((x) => x.id, 'id');
+  Subject<String> get title => has((x) => x.title, 'title');
+  Subject<String> get content => has((x) => x.content, 'content');
+}
+
 extension ZulipStreamChecks on Subject<ZulipStream> {
 }