getChatById method

Implementation

@override
Future<ChatModel> getChatById(String chatId) async {
  var currentUser = await _userService.getCurrentUser();
  var chatCollection = await _db
      .collection(_options.usersCollectionName)
      .doc(currentUser?.id)
      .collection(_options.userChatsCollectionName)
      .doc(chatId)
      .get();

  if (chatCollection.exists && chatCollection.data()?['users'] != null) {
    // ignore: avoid_dynamic_calls
    var otherUser = chatCollection.data()?['users'].firstWhere(
          (element) => element != currentUser?.id,
        );
    var user = await _userService.getUser(otherUser);
    return PersonalChatModel(
      id: chatId,
      user: user!,
      canBeDeleted: chatCollection.data()?['can_be_deleted'] ?? true,
    );
  } else {
    var groupChatCollection = await _db
        .collection(_options.chatsMetaDataCollectionName)
        .doc(chatId)
        .withConverter(
          fromFirestore: (snapshot, _) =>
              FirebaseChatDocument.fromJson(snapshot.data()!, snapshot.id),
          toFirestore: (chat, _) => chat.toJson(),
        )
        .get();
    var chat = groupChatCollection.data();
    var users = <ChatUserModel>[];
    for (var userId in chat?.users ?? []) {
      var user = await _userService.getUser(userId);
      if (user != null) {
        users.add(user);
      }
    }
    return GroupChatModel(
      id: chat?.id ?? chatId,
      title: chat?.title ?? '',
      imageUrl: chat?.imageUrl ?? '',
      users: users,
      canBeDeleted: chat?.canBeDeleted ?? true,
    );
  }
}