Modularized code

Moved all resource creation code to modules (thin cake pattern)
Cleanup
Added test actor running on fx thread

src/main/resources/application.conf

@@ -1,5 +1,5 @@
 javafx-dispatcher {
   type = "Dispatcher"
-  executor = "akka.dispatch.gui.JavaFXEventThreadExecutorServiceConfigurator"
+  executor = "nova.monadic_sfx.executors.JavaFXEventThreadExecutorServiceConfigurator"
   throughput = 1
 }

src/main/scala/nova/monadic_sfx/Main.scala

@@ -1,60 +1,22 @@
 package nova.monadic_sfx
 
-import scalafx.application.JFXApp
-import scalafx.application.JFXApp.PrimaryStage
 import monix.eval.Task
-import monix.execution.Scheduler
 // import sttp.client.asynchttpclient.monix.AsyncHttpClientMonixBackend
 // import sttp.client._
 // import sttp.client.circe._
 // import io.circe.generic.auto._
-import scala.util.Failure
-import scala.util.Success
-import akka.{actor => classic}
 import nova.monadic_sfx.executors._
 import cats.effect.Resource
-import nova.monadic_sfx.models._
-import nova.monadic_sfx.ui.DefaultUI
-import nova.monadic_sfx.http.Backend
-import nova.monadic_sfx.modules.MainModule
-import scalafx.stage.Stage
-import scalafx.scene.layout.FlowPane
-import nova.monadic_sfx.pages.LoginPage
-import scala.concurrent.duration._
 import sttp.client.asynchttpclient.monix.AsyncHttpClientMonixBackend
-import scalafx.Includes._
-import scala.concurrent.Await
-import akka.actor.typed.scaladsl.adapter._
-import scalafx.application.Platform
 import io.odin.syntax._
-// import io.odin._
 import io.odin.monix._
-import nova.monadic_sfx.pages.HomePage
-import monix.execution.Callback
 import monix.eval.TaskApp
 import cats.effect.ExitCode
-import scalafx.scene.layout.HBox
-import scalafx.scene.Scene
 import cats.implicits._
-import cats.effect.Clock
-import cats.effect.Sync
 
-object Main extends TaskApp {
+object Main extends MainModule with TaskApp {
 
-  // lazy val schedulers: Schedulers = new Schedulers()
-  // override implicit def scheduler: Scheduler = schedulers.fx
   override def run(args: List[String]): Task[ExitCode] = {
-    // val logger = consoleLogger().withAsyncUnsafe()
-
-    // lazy val backendTask = AsyncHttpClientMonixBackend()
-    // lazy val actorSystemTask = Task {
-    //   classic.ActorSystem(
-    //     name = "FXActorSystem"
-    //   )
-    // }
-
-    // implicit lazy val FSync = Sync[Task]
-    // implicit lazy val FClock = Clock[Task]
     // val startTime = Task.clock
     //   .monotonic(scala.concurrent.duration.MILLISECONDS)
     //   .map(Duration.fromNanos(_))
@@ -62,108 +24,13 @@ object Main extends TaskApp {
       // clock <- Resource.liftF(Task(Task.clock))
       logger <- consoleLogger().withAsync()
       backend <- AsyncHttpClientMonixBackend.resource()
-      actorSystem <-
-        Resource.make(logger.info("Creating Actor System") >> Task {
-          classic.ActorSystem(
-            name = "FXActorSystem"
-          )
-        })(sys =>
-          logger.info("Shutting down actor system") >> Task.fromFuture(
-            sys.terminate()
-          ) >> logger.info("Actor System terminated")
-        )
-      // _ <- Resource.liftF(logger.info(Thread.currentThread().getName()))
-      fxApp <- Resource.make(logger.info("Creating FX Application") >> Task {
-        // val appStage = makePrimaryStage(backend, actorSystem)
-        // stage = appStage
-        // val stage2 = new PrimaryStage {
-        //   scene = new Scene(new HBox())
-        // }
-        val app: JFXApp = new JFXApp {
-          lazy val schedulers: Schedulers = new Schedulers()
-
-          implicit lazy val defaultScheduler: Scheduler = schedulers.fx
-
-          val application =
-            for {
-              appStage <- logger.info("Inside JFX application stage") >> Task(
-                makePrimaryStage(backend, actorSystem)
-              )
-              _ <- Task { stage = appStage }
-              _ <- Task.sleep(2.seconds)
-              loginScene <- LoginPage(appStage, backend, actorSystem)
-              _ <- Task {
-                // appStage.maximized = true
-                appStage.height = 800
-                appStage.width = 800
-                appStage
-                  .scene()
-                  .setRoot(
-                    loginScene
-                  )
-              }
-            } yield ()
-          application.timed.runAsync(
-            new Callback[Throwable, (FiniteDuration, Unit)] {
-
-              override def onSuccess(value: (FiniteDuration, Unit)): Unit = {
-                val (duration, _) = value
-                println(
-                  s"Application started successfully in ${duration.toSeconds} seconds"
-                )
-              }
-
-              override def onError(e: Throwable): Unit = {
-                println("Application start failed. Reason -")
-                e.printStackTrace()
-              }
-
-            }
-          )
-
-          override def stopApp() = {
-            Platform.exit()
-            // System.exit(0)
-          }
-        }
-        app
-      })(app => logger.info("Stopping FX Application") >> Task(app.stopApp()))
-      // _ <- Resource.liftF(Task.unit.executeOn(defaultScheduler))
-      _ <- Resource.liftF(logger.info(Thread.currentThread().getName()))
+      actorSystem <- actorResource(logger)
+      reqs <- Resource.liftF(Task(requesters(backend, actorSystem)))
+      schedulers <- Resource.liftF(Task(new Schedulers()))
+      fxApp <- fxAppResource(logger, backend, actorSystem, reqs, schedulers)
     } yield (fxApp)
-// >> logger.info("test")
     appResource
       .use(fxApp => Task(fxApp.main(args.toArray)))
       .as(ExitCode.Success)
   }
-
-  def makePrimaryStage(
-      backend: AppTypes.HttpBackend,
-      actorSystem: classic.ActorSystem
-  ) = {
-    new PrimaryStage {
-      scene = new DefaultUI().scene
-      // onCloseRequest = () => {
-      // val f2 = actorSystem.terminate()
-      // val f1 = backend.close().runToFuture
-
-      // println("Closing backend")
-      // Await.result(f1, 3.seconds)
-      // println("Closing actor system")
-      // println(Thread.currentThread().getName())
-      // Await.result(f2, 3.seconds)
-      // println("Actor system closed")
-      // Platform.exit()
-      // System.exit(0)
-      // }
-    }
-  }
 }
-
-// class MyFxApp extends javafx.application.Application {
-
-//   override def start(stage: javafx.stage.Stage): Unit = {
-//     stage.show()
-//   }
-
-// }

src/main/scala/nova/monadic_sfx/MainModule.scala

@@ -0,0 +1,7 @@
+package nova.monadic_sfx
+
+import nova.monadic_sfx.actors.ActorModule
+import nova.monadic_sfx.ui.UiModule
+import nova.monadic_sfx.http.HttpModule
+
+trait MainModule extends ActorModule with UiModule with HttpModule

src/main/scala/nova/monadic_sfx/actors/ActorModule.scala

@@ -0,0 +1,49 @@
+package nova.monadic_sfx.actors
+
+import io.odin.Logger
+import monix.eval.Task
+import cats.effect.Resource
+import akka.actor._
+import akka.actor.typed.scaladsl.adapter._
+import akka.actor.typed.scaladsl.Behaviors
+import com.softwaremill.macwire._
+import akka.actor.typed.Behavior
+import akka.actor.typed.DispatcherSelector
+
+trait ActorModule {
+  def actorResource(logger: Logger[Task]): Resource[Task, ActorSystem] =
+    Resource.make(logger.info("Creating Actor System") >> Task {
+      ActorSystem(
+        name = "FXActorSystem"
+      )
+    })(sys =>
+      logger.info("Shutting down actor system") >> Task.fromFuture(
+        sys.terminate()
+      ) >> logger.info("Actor System terminated")
+    )
+
+  def testActor(
+      system: ActorSystem
+  ): akka.actor.typed.ActorRef[Counter.Command] = {
+    val behaviour: Behavior[Counter.Command] =
+      Behaviors.setup(context => wire[Counter])
+    system.spawn(
+      behaviour,
+      "CounterActor",
+      DispatcherSelector.fromConfig("javafx-dispatcher")
+    )
+  }
+
+  def testActorL(
+      system: ActorSystem
+  ): Task[akka.actor.typed.ActorRef[Counter.Command]] =
+    Task {
+      val behaviour: Behavior[Counter.Command] =
+        Behaviors.setup(context => wire[Counter])
+      system.spawn(
+        behaviour,
+        "CounterActor",
+        DispatcherSelector.fromConfig("javafx-dispatcher")
+      )
+    }
+}

src/main/scala/nova/monadic_sfx/actors/TestActor.scala

@@ -0,0 +1,34 @@
+package nova.monadic_sfx.actors
+
+import akka.actor.typed._
+import akka.actor.typed.scaladsl._
+
+object Counter {
+  sealed trait Command
+  case object Increment extends Command
+  final case class GetValue(replyTo: ActorRef[Value]) extends Command
+  final case class Value(n: Int)
+
+  def apply(): Behavior[Command] = {
+    Behaviors.setup(context => new Counter(context))
+  }
+}
+
+class Counter(context: ActorContext[Counter.Command])
+    extends AbstractBehavior[Counter.Command](context) {
+  import Counter._
+
+  private var n = 0
+
+  override def onMessage(msg: Command): Behavior[Counter.Command] = {
+    msg match {
+      case Increment =>
+        n += 1
+        context.log.debug("Incremented counter to [{}]", n)
+        this
+      case GetValue(replyTo) =>
+        replyTo ! Value(n)
+        Behaviors.stopped
+    }
+  }
+}

src/main/scala/nova/monadic_sfx/executors/ExecutorsModule.scala

@@ -0,0 +1,5 @@
+package nova.monadic_sfx.executors
+
+trait ExecutorsModule {
+  lazy val schedulers = new Schedulers()
+}

src/main/scala/nova/monadic_sfx/executors/GUIExecutor.scala

@@ -20,7 +20,7 @@ import scala.concurrent.ExecutionContext
 import java.util.concurrent.Executor
 
 // First we wrap invokeLater/runLater as an ExecutorService
-abstract class GUIExecutorService extends AbstractExecutorService {
+trait GUIExecutorService extends AbstractExecutorService {
   def execute(command: Runnable): Unit
 
   def shutdown(): Unit = ()

src/main/scala/nova/monadic_sfx/http/Backend.scala

@@ -1,10 +0,0 @@
-package nova.monadic_sfx.http
-
-import sttp.client.asynchttpclient.monix.AsyncHttpClientMonixBackend
-import nova.monadic_sfx.AppTypes
-
-object Backend {
-  val backend = AsyncHttpClientMonixBackend
-    .resource()
-  def apply() = { backend }
-}

src/main/scala/nova/monadic_sfx/http/HttpModule.scala

@@ -0,0 +1,28 @@
+package nova.monadic_sfx.http
+
+import nova.monadic_sfx.http.requests.DummyRequest
+import nova.monadic_sfx.AppTypes
+
+trait HttpModule {
+  def requesters(
+      backend: AppTypes.HttpBackend,
+      system: akka.actor.ActorSystem
+  ): Requesters = {
+    import com.softwaremill.macwire._
+    val dummyRequester = wire[DummyRequest]
+    wire[Requesters]
+  }
+}
+
+class Requesters(val dummyRequester: DummyRequest)
+
+// object Requesters {
+//   def apply(
+//       backend: AppTypes.HttpBackend,
+//       system: akka.actor.ActorSystem
+//   ): Requesters = {
+//     import com.softwaremill.macwire._
+//     val dummyRequester = wire[DummyRequest]
+//     wire[Requesters]
+//   }
+// }

src/main/scala/nova/monadic_sfx/http/requests/DummyRequest.scala

@@ -8,20 +8,36 @@ import sttp.client._
 import sttp.client.circe._
 import io.circe.generic.auto._
 import nova.monadic_sfx.models._
+import cats.data.EitherT
 
 class DummyRequest(backend: HttpBackend) extends AppTypes {
   private implicit val _backend = backend
   def send() = {
     Task
-      .suspend(
-        (for {
+      .suspend {
+        for {
           req <-
             basicRequest
               .get(uri"https://httpbin.org/get")
               .response(asJson[HttpBinResponse])
               .send()
-        } yield println(req)) >>
-          Task(println(Thread.currentThread().getName()))
-      )
+        } yield (req)
+      }
+
+  }
+
+  def test() = {
+    for {
+      res <- send()
+      res3 <- Task { res.body }
+      res2 <- Task {
+        res3.fold(
+          err => {
+            err.toString()
+          },
+          value => value.toString()
+        )
+      }
+    } yield (res3)
   }
 }

src/main/scala/nova/monadic_sfx/modules/MainModule.scala

@@ -1,79 +0,0 @@
-package nova.monadic_sfx.modules
-
-import nova.monadic_sfx.executors.Schedulers
-import monix.execution.Scheduler
-import nova.monadic_sfx.http.requests.DummyRequest
-import monix.eval.Task
-import akka.{actor => classic}
-import cats.effect.Resource
-import nova.monadic_sfx.AppTypes
-
-trait MainModule {
-  import com.softwaremill.macwire._
-//   val schedulers: Schedulers = new Schedulers()
-
-//   implicit val defaultScheduler: Scheduler = schedulers.fx
-
-//   val program =
-//     for {
-//       backend <- Backend()
-//       fxActorSystem <-
-//         Resource
-//           .make(Task {
-//             classic.ActorSystem(
-//               name = "FXActorSystem"
-//             )
-//           })(sys => Task(sys.terminate()))
-
-//     } yield {
-//       val dummyRequester = wire[DummyRequest]
-//       dummyRequester.send()
-//     }
-
-//   val program = Backend().use(backend =>
-//     Resource
-//       .make(Task {
-//         classic.ActorSystem(
-//           name = "FXActorSystem"
-//         )
-//       })(sys => Task(sys.terminate()))
-//       .use { implicit system =>
-//         // system.spa
-//         // system.typed
-//         // val javaFxActor = system.actorOf(
-//         //   Props[JavaFxActor]().withDispatcher("javafx-dispatcher"),
-//         //   "javaFxActor"
-//         // )
-//         // val swingActor = system.actorOf(
-//         //   Props[SwingActor]().withDispatcher("swing-dispatcher"),
-//         //   "swingActor"
-//         // )
-//         Task(new DummyRequest(backend)) >>
-//           Task.unit
-//       }
-//   )
-  def schedulers: Schedulers
-
-  def defaultScheduler: Scheduler
-
-  def backendTask: Task[AppTypes.HttpBackend]
-  def actorSystemTask: Task[classic.ActorSystem]
-
-  def deps =
-    for {
-      backend <- backendTask
-      actorSystem <- actorSystemTask
-      dummyRequesterTask <- Task {
-        wireDeps(backend, actorSystem)
-      }
-    } yield dummyRequesterTask
-
-  def wireDeps(
-      backend: AppTypes.HttpBackend,
-      system: classic.ActorSystem
-  ): DummyRequest = {
-    wire[DummyRequest]
-    // new DummyRequest(backend)
-  }
-
-}

src/main/scala/nova/monadic_sfx/pages/HomePage.scala

@@ -1,39 +0,0 @@
-package nova.monadic_sfx.pages
-import nova.monadic_sfx.AppTypes
-import scalafx.scene.control.TextField
-import scalafx.scene.control._
-import scalafx.scene.layout.VBox
-import scalafx.scene.Node
-import scalafx.Includes._
-import scalafx.scene.layout.HBox
-import scalafx.scene.text.Text
-import scalafx.scene.Parent
-import scalafx.application.JFXApp.PrimaryStage
-
-class HomePage(
-    backend: AppTypes.HttpBackend,
-    system: akka.actor.ActorSystem,
-    onLogout: () => Unit
-) {
-  private lazy val root = new HBox {
-    children = List(
-      new Text {
-        text = "hello"
-      },
-      new Button {
-        text = "logout"
-        onAction = () => onLogout()
-      }
-    )
-  }
-  def render = root
-}
-
-object HomePage {
-  def apply(
-      backend: AppTypes.HttpBackend,
-      system: akka.actor.ActorSystem,
-      onLogout: () => Unit
-  ): Parent =
-    new HomePage(backend, system, onLogout).render
-}

src/main/scala/nova/monadic_sfx/pages/LoginPage.scala

@@ -1,102 +0,0 @@
-package nova.monadic_sfx.pages
-import nova.monadic_sfx.AppTypes
-import scalafx.scene.control.TextField
-import scalafx.scene.control._
-import scalafx.scene.layout.VBox
-import scalafx.scene.Node
-import scalafx.Includes._
-import scalafx.scene.Parent
-import scalafx.application.JFXApp.PrimaryStage
-import nova.monadic_sfx.http.requests.DummyRequest
-import monix.eval.Task
-import monix.execution.Scheduler
-// import io.odin.syntax._
-// import _root_.monix.eval.Task
-// import io.odin.monix._
-// import javafx.beans.property.ObjectProperty
-// import javafx.event.{ActionEvent, EventHandler}
-class LoginPage(
-    appStage: PrimaryStage,
-    backend: AppTypes.HttpBackend,
-    system: akka.actor.ActorSystem
-) {
-
-  val dummyRequester = new DummyRequest(backend)
-
-  //pure function callbacks, but with side effects still
-  private def onLogout(stage: PrimaryStage) =
-    for {
-      _ <- Task { println("logging out") }
-      root <- render
-      _ <- Task(stage.scene().setRoot(root))
-    } yield ()
-
-  private def onLogin(stage: PrimaryStage) =
-    Task.deferAction { implicit Scheduler =>
-      for {
-        _ <- Task(println("logging in"))
-        root <- Task {
-          stage
-            .scene()
-            .setRoot(
-              HomePage(
-                backend,
-                system,
-                () => runFxTask(onLogout(appStage))
-              )
-            )
-        }
-      } yield ()
-    }
-
-  private lazy val root = Task.deferAction(implicit scheduler =>
-    Task {
-      new VBox {
-        children = Seq(
-          new Label {
-            text = "username"
-          },
-          new TextField(),
-          new Label {
-            text = "password"
-          },
-          new TextField(),
-          new Button {
-            text = "Login"
-            onAction = () =>
-              runFxTask {
-                Task
-                  .parZip2(
-                    dummyRequester
-                      .send(),
-                    // .executeOn(Scheduler.global)
-                    onLogin(appStage)
-                  )
-              }
-          }
-        )
-      }
-    }
-  )
-  def render: Task[Parent] = root
-
-  /**
-    * Implicitly runs monix task as fire and forget. \
-    * For use in ScalaFX callbacks.
-    *
-    * @param task
-    * @param s
-    */
-  def runFxTask[T](task: => Task[T])(implicit s: Scheduler) = {
-    task.runAsyncAndForget
-  }
-
-}
-
-object LoginPage {
-  def apply(
-      appStage: PrimaryStage,
-      backend: AppTypes.HttpBackend,
-      system: akka.actor.ActorSystem
-  ) = new LoginPage(appStage, backend, system).render
-}

src/main/scala/nova/monadic_sfx/ui/MyFxApp.scala

@@ -0,0 +1,90 @@
+package nova.monadic_sfx.ui
+
+import scalafx.application.JFXApp
+import nova.monadic_sfx.executors.Schedulers
+import monix.execution.Scheduler
+import monix.eval.Task
+import nova.monadic_sfx.screens.LoginScreen
+import nova.monadic_sfx.AppTypes
+import scalafx.application.Platform
+import scala.concurrent.duration._
+import io.odin.Logger
+import monix.execution.Callback
+import com.softwaremill.macwire._
+import nova.monadic_sfx.http.Requesters
+
+import akka.actor._
+import akka.actor.typed.Behavior
+import akka.actor.typed.scaladsl.adapter._
+import akka.actor.typed.scaladsl.Behaviors
+import nova.monadic_sfx.actors.Counter
+import akka.actor.typed.DispatcherSelector
+
+class MyFxApp(
+    logger: Logger[Task],
+    backend: AppTypes.HttpBackend,
+    actorSystem: akka.actor.ActorSystem,
+    requesters: Requesters,
+    schedulers: Schedulers
+) extends JFXApp {
+
+  implicit lazy val defaultScheduler: Scheduler = schedulers.fx
+
+  lazy val application =
+    for {
+      appStage <- Task(
+        UiModule.makePrimaryStage(backend, actorSystem)
+      )
+      //   _ <- Task {
+      //     val counterActor = testActor(actorSystem)
+      //     counterActor ! (Counter.Increment)
+      //   }
+      _ <- Task { stage = appStage }
+      _ <- Task.sleep(2.seconds)
+      loginScene <- wire[LoginScreen].render
+      _ <- Task {
+        // appStage.maximized = true
+        appStage.height = 800
+        appStage.width = 800
+        appStage
+          .scene()
+          .setRoot(
+            loginScene
+          )
+      }
+    } yield ()
+
+  def testActor(
+      system: ActorSystem
+  ): akka.actor.typed.ActorRef[Counter.Command] = {
+    val behaviour: Behavior[Counter.Command] =
+      Behaviors.setup(context => wire[Counter])
+    system.spawn(
+      behaviour,
+      "CounterActor",
+      DispatcherSelector.fromConfig("javafx-dispatcher")
+    )
+  }
+
+  application.timed.runAsync(
+    new Callback[Throwable, (FiniteDuration, Unit)] {
+
+      override def onSuccess(value: (FiniteDuration, Unit)): Unit = {
+        val (duration, _) = value
+        println(
+          s"Application started successfully in ${duration.toSeconds} seconds"
+        )
+      }
+
+      override def onError(e: Throwable): Unit = {
+        println("Application start failed. Reason -")
+        e.printStackTrace()
+      }
+
+    }
+  )
+
+  override def stopApp() = {
+    Platform.exit()
+  }
+}

src/main/scala/nova/monadic_sfx/ui/UiModule.scala

@@ -0,0 +1,37 @@
+package nova.monadic_sfx.ui
+
+import scalafx.application.JFXApp
+import monix.eval.Task
+import nova.monadic_sfx.AppTypes
+import scalafx.application.JFXApp.PrimaryStage
+import io.odin.Logger
+import cats.effect.Resource
+import com.softwaremill.macwire._
+import nova.monadic_sfx.http.Requesters
+import nova.monadic_sfx.executors.Schedulers
+
+trait UiModule {
+  def fxAppResource(
+      logger: Logger[Task],
+      backend: AppTypes.HttpBackend,
+      actorSystem: akka.actor.ActorSystem,
+      requesters: Requesters,
+      schedulers: Schedulers
+  ): Resource[Task, JFXApp] =
+    Resource.make(logger.info("Creating FX Application") >> Task {
+      val app: JFXApp = wire[MyFxApp]
+      app
+    })(app => logger.info("Stopping FX Application") >> Task(app.stopApp()))
+
+}
+
+object UiModule {
+  def makePrimaryStage(
+      backend: AppTypes.HttpBackend,
+      actorSystem: akka.actor.ActorSystem
+  ) = {
+    new PrimaryStage {
+      scene = new DefaultUI().scene
+    }
+  }
+}

src/main/scala/nova/monadic_sfx/ui/screens/HomeScreen.scala

@@ -0,0 +1,45 @@
+package nova.monadic_sfx.screens
+import nova.monadic_sfx.AppTypes
+import scalafx.scene.control.TextField
+import scalafx.scene.control._
+import scalafx.scene.layout.VBox
+import scalafx.scene.Node
+import scalafx.Includes._
+import scalafx.scene.layout.HBox
+import scalafx.scene.text.Text
+import scalafx.scene.Parent
+import scalafx.application.JFXApp.PrimaryStage
+import monix.eval.Task
+import nova.monadic_sfx.util.Action
+
+class HomeScreen(
+    backend: AppTypes.HttpBackend,
+    system: akka.actor.ActorSystem,
+    onLogout: () => Task[Unit]
+) {
+  private lazy val root = Task.deferAction { implicit s =>
+    Task {
+      new HBox {
+        children = List(
+          new Text {
+            text = "hello"
+          },
+          new Button {
+            text = "logout"
+            onAction = () => Action.asyncT(onLogout())
+          }
+        )
+      }
+    }
+  }
+  def render = root
+}
+
+object HomeScreen {
+  def apply(
+      backend: AppTypes.HttpBackend,
+      system: akka.actor.ActorSystem,
+      onLogout: () => Task[Unit]
+  ): Task[Parent] =
+    new HomeScreen(backend, system, onLogout).render
+}

src/main/scala/nova/monadic_sfx/ui/screens/LoginScreen.scala

@@ -0,0 +1,108 @@
+package nova.monadic_sfx.screens
+import nova.monadic_sfx.AppTypes
+import scalafx.scene.control.TextField
+import scalafx.scene.control._
+import scalafx.scene.layout.VBox
+import scalafx.scene.Node
+import scalafx.Includes._
+import scalafx.scene.Parent
+import scalafx.application.JFXApp.PrimaryStage
+import nova.monadic_sfx.http.requests.DummyRequest
+import monix.eval.Task
+import monix.execution.Scheduler
+import cats.effect.Effect
+import cats.effect.implicits._
+import nova.monadic_sfx.util.Action
+import io.odin.Logger
+import nova.monadic_sfx.http.Requesters
+import sttp.client.Response
+import nova.monadic_sfx.models.HttpBinResponse
+import sttp.client.ResponseError
+import nova.monadic_sfx.executors.Schedulers
+import nova.monadic_sfx.ui.screens.Screen
+// import io.odin.syntax._
+// import _root_.monix.eval.Task
+// import io.odin.monix._
+// import javafx.beans.property.ObjectProperty
+// import javafx.event.{ActionEvent, EventHandler}
+class LoginScreen(
+    override protected val appStage: PrimaryStage,
+    logger: Logger[Task],
+    backend: AppTypes.HttpBackend,
+    system: akka.actor.ActorSystem,
+    requesters: Requesters,
+    schedulers: Schedulers
+) extends Screen {
+  val dummyRequester: DummyRequest = requesters.dummyRequester
+  //pure function callbacks, but with side effects still
+
+  // lazy val hs = {
+  //   import com.softwaremill.macwire._
+  //   lazy val action = () => onLogout(appStage)
+  //   wire[HomeScreen]
+  // }
+
+  private def onLogout(stage: PrimaryStage) =
+    for {
+      _ <- logger.info("Logging out")
+      root <- render
+      _ <- changeRootL(root)
+    } yield ()
+
+  private def onLogin(stage: PrimaryStage) =
+    for {
+      _ <- logger.info("Logging in")
+      homeScreen <- HomeScreen(
+        backend,
+        system,
+        () => onLogout(appStage)
+      )
+      _ <- Task { stage.scene().setRoot(homeScreen) }
+    } yield ()
+
+  private lazy val root = Task.deferAction(implicit scheduler =>
+    Task {
+      new VBox {
+        children = Seq(
+          new Label {
+            text = "username"
+          },
+          new TextField(),
+          new Label {
+            text = "password"
+          },
+          new TextField(),
+          new Button {
+            text = "Login"
+            onAction = () =>
+              Action.asyncT {
+                Task
+                  .parSequence(
+                    List(
+                      testRequest,
+                      // .executeOn(Scheduler.global)
+                      onLogin(appStage)
+                    )
+                  )
+              }
+          }
+        )
+      }
+    }
+  )
+  def render: Task[Parent] = root
+
+  val testRequest = for {
+    res <- dummyRequester.send()
+    _ <- logger.info(res.body.toString())
+  } yield ()
+
+}
+
+// object LoginScreen {
+//   def apply(
+//       appStage: PrimaryStage,
+//       backend: AppTypes.HttpBackend,
+//       system: akka.actor.ActorSystem
+//   ) = new LoginScreen(appStage, backend, system).render
+// }

src/main/scala/nova/monadic_sfx/ui/screens/Screen.scala

@@ -0,0 +1,13 @@
+package nova.monadic_sfx.ui.screens
+
+import scalafx.application.JFXApp.PrimaryStage
+import scalafx.scene.Parent
+import monix.eval.Task
+
+trait Screen {
+  protected def appStage: PrimaryStage
+  def changeRoot(root: Parent): Unit = {
+    appStage.scene().setRoot(root)
+  }
+  def changeRootL(root: Parent): Task[Unit] = Task(changeRoot(root))
+}

src/main/scala/nova/monadic_sfx/util/Action.scala

@@ -0,0 +1,23 @@
+package nova.monadic_sfx.util
+
+import monix.eval.Task
+import monix.execution.Scheduler
+import cats.effect.Effect
+import cats.effect.implicits._
+
+object Action {
+
+  /**
+    * Implicitly runs monix task as fire and forget. \
+    * For use in ScalaFX callbacks.
+    *
+    * @param task
+    * @param s
+    */
+  def asyncT[T](task: => Task[T])(implicit s: Scheduler): Unit = {
+    task.runAsyncAndForget
+  }
+
+  def asyncF[F[_]: Effect, T](cb: => F[T]): Unit =
+    cb.toIO.unsafeRunAsyncAndForget()
+}