Navigator.kt

enum class Screen(var screen: String) {
   ERROR("Error"),
   INVASIVE_SPECIES_MAP("Invasive Species Map"),
   SPOTTER("Spotter");

   override fun toString(): String = screen
}

class Navigator(
   private val navController: NavController,
   private val resources: Resources
) {

   fun navigateToError(from: Screen) {
      val currentDestination = navController.currentDestination?.id
       if (currentDestination != R.id.errorFragment) {
           val bundle = bundleOf(
               PREVIOUS_DESTINATION_ID to from.fragmentId(),
               PREVIOUS_DESTINATION_LABEL to from.fragmentLabel()

           )
           navController.navigate(R.id.action_go_to_error, bundle)
       }
   }

   fun navigateToInvasiveSpeciesMap() {
       if (navController.currentDestination?.id != Screen.INVASIVE_SPECIES_MAP.fragmentId()) {
           navController.navigate(R.id.action_go_to_invasive_species_map)
       }
   }

   private fun Screen.fragmentId(): Int {
       return when (this) {
           Screen.INVASIVE_SPECIES_MAP -> R.id.invasiveSpeciesMapFragment
           else -> R.id.errorFragment
       }
   }

   private fun Screen.fragmentLabel(): String {
       return when (this) {
           Screen.INVASIVE_SPECIES_MAP -> resources.getString(R.string.invasive_species_map_label)
           else -> resources.getString(R.string.generalMessageError)
       }
   }

   companion object {
       const val PREVIOUS_DESTINATION_ID = "PREVIOUS_DESTINATION_ID"
       const val PREVIOUS_DESTINATION_LABEL = "PREVIOUS_DESTINATION_LABEL"
   }
}