ChatRoomViewModel.swift

final class ChatRoomViewModel: ObservableObject {
    /// service used to send message to chat room
    private let messagingService: MessageSendable
    
    /// username of current user of application
    private(set) var username: String
    
    /// current message typed in view
    @Published var typedMessage = ""
    
    
    /// message to display to user upon error
    @Published var errorMessage: String? = nil
    
    
    /// constructor that injects services used within the view model
    init(messagingService: MessageSendable, username: String) {
        self.messagingService = messagingService
        self.username = username
    }
   
    //MARK - intents
    //... implementation of intents left out for readability
}