Default reducer implementation

DefaultReducer.kt

class DefaultReducer(
    private val resources: Resources,
) : Reducer<Mutation, ViewState> {
    
     override fun invoke(mutation: Mutation, currentState: ViewState): ViewState =
        when (mutation) {
            Mutation.DismissLostConnection ->
                currentState.mutateToDismissLostConnection()
            is Mutation.ShowContent ->
                currentState.mutateToShowContent(users = mutation.users)
            is Mutation.ShowError ->
                currentState.mutateToShowError(exception = mutation.exception)
            Mutation.ShowLoader ->
                currentState.mutateToShowLoader()
            Mutation.ShowLostConnection ->
                currentState.mutateToShowLostConnection()
        }

    private fun ViewState.mutateToShowContent(users: List<UserDataModel>) =
        copy(
            isLoaderVisible = false,
            isUserListVisible = true,
            userStates = userStates.toMutableList().apply {
                addAll(users.map { it.toUserState() })
            },
            isErrorVisible = false,
        )

    private fun ViewState.mutateToShowError(exception: Exception) =
        copy(
            isLoaderVisible = false,
            isUserListVisible = false,
            isErrorVisible = true,
            errorMessage = resources.getString(R.string.userlist_text_generic_error)
                .format(exception.message),
        )
        
    private fun ItemModel.toItemState() = ...
    
    ...
}