api: Add save_snippet events and handle live-updates

Signed-off-by: Zixuan James Li <zixuan@zulip.com>

Author: PIG208

lib/api/model/events.dart

@@ -37,6 +37,12 @@ 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 '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 +342,54 @@ 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 `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/events.g.dart

@@ -0,0 +1,27 @@
+import '../api/model/events.dart';
+import '../api/model/model.dart';
+
+mixin SavedSnippetStore {
+  Iterable<SavedSnippet> get savedSnippets;
+}
+
+class SavedSnippetStoreImpl with SavedSnippetStore {
+  SavedSnippetStoreImpl({required Iterable<SavedSnippet> savedSnippets})
+    : _savedSnippets = Map.fromIterable(
+        savedSnippets, key: (x) => (x as SavedSnippet).id);
+
+  @override
+  Iterable<SavedSnippet> get savedSnippets => _savedSnippets.values;
+
+  final Map<int, SavedSnippet> _savedSnippets;
+
+  void handleSavedSnippetsEvent(SavedSnippetsEvent event) {
+    switch (event) {
+      case SavedSnippetsAddEvent(:final savedSnippet):
+        _savedSnippets[savedSnippet.id] = savedSnippet;
+
+      case SavedSnippetsRemoveEvent(:final savedSnippetId):
+        _savedSnippets.remove(savedSnippetId);
+    }
+  }
+}

lib/model/saved_snippet.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 'typing_status.dart';
 import 'unreads.dart';
 import 'user.dart';
@@ -295,7 +296,7 @@ class AccountNotFoundException implements Exception {}
 /// 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 ChangeNotifier with EmojiStore, UserStore, ChannelStore, MessageStore {
+class PerAccountStore extends ChangeNotifier with EmojiStore, UserStore, SavedSnippetStore, ChannelStore, MessageStore {
   /// Construct a store for the user's data, starting from the given snapshot.
   ///
   /// The global store must already have been updated with
@@ -337,6 +338,8 @@ class PerAccountStore extends ChangeNotifier with EmojiStore, UserStore, Channel
       emoji: EmojiStoreImpl(
         realmUrl: realmUrl, allRealmEmoji: initialSnapshot.realmEmoji),
       accountId: accountId,
+      savedSnippets: SavedSnippetStoreImpl(
+        savedSnippets: initialSnapshot.savedSnippets ?? []),
       userSettings: initialSnapshot.userSettings,
       typingNotifier: TypingNotifier(
         connection: connection,
@@ -379,6 +382,7 @@ class PerAccountStore extends ChangeNotifier with EmojiStore, UserStore, Channel
     required this.emailAddressVisibility,
     required EmojiStoreImpl emoji,
     required this.accountId,
+    required SavedSnippetStoreImpl savedSnippets,
     required this.userSettings,
     required this.typingNotifier,
     required UserStoreImpl users,
@@ -395,6 +399,7 @@ class PerAccountStore extends ChangeNotifier with EmojiStore, UserStore, Channel
        _realmEmptyTopicDisplayName = realmEmptyTopicDisplayName,
        _emoji = emoji,
        _users = users,
+        _savedSnippets = savedSnippets,
        _channels = channels,
        _messages = messages;
 
@@ -499,6 +504,10 @@ class PerAccountStore extends ChangeNotifier with EmojiStore, UserStore, Channel
   /// Will throw if called after [dispose] has been called.
   Account get account => _globalStore.getAccount(accountId)!;
 
+  @override
+  Iterable<SavedSnippet> get savedSnippets => _savedSnippets.savedSnippets;
+  final SavedSnippetStoreImpl _savedSnippets; // TODO(server-10)
+
   final UserSettings? userSettings; // TODO(server-5)
 
   final TypingNotifier typingNotifier;
@@ -726,6 +735,11 @@ class PerAccountStore extends ChangeNotifier with EmojiStore, UserStore, Channel
         autocompleteViewManager.handleRealmUserUpdateEvent(event);
         notifyListeners();
 
+      case SavedSnippetsEvent():
+        assert(debugLog('server event: saved_snippet/${event.op}'));
+        _savedSnippets.handleSavedSnippetsEvent(event);
+        notifyListeners();
+
       case ChannelEvent():
         assert(debugLog("server event: stream/${event.op}"));
         _channels.handleChannelEvent(event);

lib/model/store.dart

@@ -21,6 +21,10 @@ 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');
+}
+
 extension ZulipStreamChecks on Subject<ZulipStream> {
 }
 

test/api/model/model_checks.dart

@@ -233,6 +233,28 @@ final User thirdUser = user(fullName: 'Third User');
 
 final User fourthUser  = user(fullName: 'Fourth User');
 
+////////////////////////////////////////////////////////////////
+// Data attached to the self-account on the realm
+//
+
+int _nextSavedSnippetId() => _lastSavedSnippetId++;
+int _lastSavedSnippetId = 1;
+
+SavedSnippet savedSnippet({
+  int? id,
+  String? title,
+  String? content,
+  int? dateCreated,
+}) {
+  _checkPositive(id, 'saved snippet ID');
+  return SavedSnippet(
+    id: id ?? _nextSavedSnippetId(),
+    title: title ?? 'A saved snippet',
+    content: content ?? 'foo bar baz',
+    dateCreated: dateCreated ?? 1741390853,
+  );
+}
+
 ////////////////////////////////////////////////////////////////
 // Streams and subscriptions.
 //

test/example_data.dart

@@ -0,0 +1,26 @@
+import 'package:checks/checks.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:zulip/api/model/events.dart';
+import 'package:zulip/api/model/model.dart';
+
+import '../api/model/model_checks.dart';
+import '../example_data.dart' as eg;
+import 'store_checks.dart';
+
+void main() {
+  test('handleSavedSnippetEvent', () {
+    final store = eg.store(initialSnapshot: eg.initialSnapshot(
+      savedSnippets: [eg.savedSnippet(id: 101)]));
+
+    store.handleEvent(SavedSnippetsAddEvent(
+      id: 1, savedSnippet: eg.savedSnippet(id: 102)));
+    check(store).savedSnippets.deepEquals(<Condition<Object?>>[
+      (it) => it.isA<SavedSnippet>().id.equals(101),
+      (it) => it.isA<SavedSnippet>().id.equals(102),
+    ]);
+
+    store.handleEvent(SavedSnippetsRemoveEvent(
+      id: 2, savedSnippetId: 101));
+    check(store).savedSnippets.single.id.equals(102);
+  });
+}

test/model/saved_snippet.dart

@@ -45,6 +45,7 @@ extension PerAccountStoreChecks on Subject<PerAccountStore> {
   Subject<int> get accountId => has((x) => x.accountId, 'accountId');
   Subject<Account> get account => has((x) => x.account, 'account');
   Subject<int> get selfUserId => has((x) => x.selfUserId, 'selfUserId');
+  Subject<Iterable<SavedSnippet>> get savedSnippets => has((x) => x.savedSnippets, 'savedSnippets');
   Subject<UserSettings?> get userSettings => has((x) => x.userSettings, 'userSettings');
   Subject<Map<int, ZulipStream>> get streams => has((x) => x.streams, 'streams');
   Subject<Map<String, ZulipStream>> get streamsByName => has((x) => x.streamsByName, 'streamsByName');