readChat method

Future<ChatEventsVersionedMixin?> readChat(
  1. ChatId chatId,
  2. ChatItemId untilId
)

Marks the specified Chat as read for the authenticated MyUser until the specified ChatItem inclusively.

There is no notion of a single ChatItem being read or not separately in a Chat. Only a whole Chat as a sequence of ChatItems can be read until some its position (concrete ChatItem). So, any ChatItem may be considered as read or not by comparing its ChatItem.at with the LastChatRead.at of the authenticated MyUser: if it's below (less or equal) then the ChatItem is read, otherwise it's unread.

This mutation should be called whenever the authenticated MyUser reads new ChatItems appeared in the Chat's UI and directly influences the Chat.unreadCount value.

Authentication

Mandatory.

Result

Only the following ChatEvent may be produced on success:

Idempotent

Succeeds as no-op (and returns no ChatEvent) if the specified Chat is already read by the authenticated MyUser until the specified ChatItem.

Implementation

Future<ChatEventsVersionedMixin?> readChat(
  ChatId chatId,
  ChatItemId untilId,
) async {
  Log.debug('readChat($chatId, $untilId)', '$runtimeType');

  final variables = ReadChatArguments(id: chatId, untilId: untilId);
  final QueryResult result = await client.mutate(
    MutationOptions(
      operationName: 'ReadChat',
      document: ReadChatMutation(variables: variables).document,
      variables: variables.toJson(),
    ),
    onException:
        (data) => ReadChatException(
          (ReadChat$Mutation.fromJson(data).readChat
                  as ReadChat$Mutation$ReadChat$ReadChatError)
              .code,
        ),
  );
  return (ReadChat$Mutation.fromJson(result.data!).readChat
      as ChatEventsVersionedMixin?);
}