import io.ktor.server.application.*
import io.ktor.server.cio.*
import io.ktor.server.engine.*
import io.ktor.server.response.*
import io.ktor.server.routing.*
import java.io.File
import java.util.*

fun main(args: Array<String>) {

  val propertiesPath = args.firstOrNull() 
    ?: error("missing properties file arg")
  
  val propertiesFile = File(propertiesPath).takeIf(File::exists) 
    ?: error("could not find properties file $propertiesPath")
  
  val properties = propertiesFile.reader().use { reader ->
    Properties().apply { load(reader) }.map { (k, v) -> k.toString() to v.toString() }
  }

  embeddedServer(
    CIO,
    port = 8080,
    module = Application::myApplicationModule
  ).start(wait = true)
}

fun Application.myApplicationModule(
  properties: Map<String, String>
) {
  routing {
    get("/") {
      call.respondText(properties["helloWorldResponse"]!!)
    }
  }
}