refactoring and scaffolding

imperative-shell/event-loop.sml

@@ -3,18 +3,19 @@ struct
   open CML
   open InputMessage
 
-  fun update inputMailbox =
+  local
+  fun loop (inputMailbox, drawMailbox, mouseX, mouseY, model) =
     let
-      val _ =
-        case Mailbox.recv inputMailbox of
-          MOUSE_MOVE {x, y} =>
-            print (String.concat
-              ["x pos: ", Int.toString x, ", y pos: ", Int.toString y, "\n"])
-        | MOUSE_LEFT_CLICK => print "clicked mouse\n"
-        | MOUSE_LEFT_RELEASE => print "released mouse\n"
+      val inputMsg = Mailbox.recv inputMailbox
+      val (model, drawMsg, mouseX, mouseY) = AppUpdate.update (model, mouseX, mouseY, inputMsg)
+      val _ = Mailbox.send (drawMailbox, drawMsg)
     in
-      update inputMailbox
+      loop (inputMailbox, drawMailbox, mouseX, mouseY, model)
     end
+  in
+    fun update (inputMailbox, drawMailbox) =
+      loop (inputMailbox, drawMailbox, 0, 0, AppType.initial)
+  end
 
   fun draw (window, graphDrawObject, buttonDrawObject, buttonDrawLength) =
     if not (Glfw.windowShouldClose window) then

imperative-shell/input-callbacks.sml

@@ -14,4 +14,18 @@ struct
         Mailbox.send (mailbox, MOUSE_LEFT_RELEASE)
     else
       ()
+
+  fun registerCallbacks (window, inputMailbox) =
+        let
+          val mouseMoveCallback = mouseMoveCallback inputMailbox
+          val _ = Input.exportMouseMoveCallback mouseMoveCallback
+          val _ = Input.setMouseMoveCallback window
+
+          val mouseClickCallback =
+            mouseClickCallback inputMailbox
+          val _ = Input.exportMouseClickCallback mouseClickCallback
+          val _ = Input.setMouseClickCallback window
+        in
+          ()
+        end
 end

imperative-shell/shell.sml

@@ -17,24 +17,13 @@ struct
       val buttonDrawObject = AppDraw.initButton ()
 
       val inputMailbox = Mailbox.mailbox ()
-      (* Set callback sender *)
-      val _ = CML.spawn (fn () =>
-        let
-          val mouseMoveCallback = InputCallbacks.mouseMoveCallback inputMailbox
-          val _ = Input.exportMouseMoveCallback mouseMoveCallback
-          val _ = Input.setMouseMoveCallback window
+      val drawMailbox = Mailbox.mailbox ()
 
-          val mouseClickCallback =
-            InputCallbacks.mouseClickCallback inputMailbox
-          val _ = Input.exportMouseClickCallback mouseClickCallback
-          val _ = Input.setMouseClickCallback window
-        in
-          ()
-        end)
-      (* Set callback listener *)
-      val _ = CML.spawn (fn () => EventLoop.update inputMailbox)
+      val _ = CML.spawn (fn () => InputCallbacks.registerCallbacks (window, inputMailbox))
+      val _ = CML.spawn (fn () => EventLoop.update (inputMailbox, drawMailbox))
+      val _ = CML.spawn (fn () => EventLoop.draw (window, graphDrawObject, buttonDrawObject, 0))
     in
-      EventLoop.draw (window, graphDrawObject, buttonDrawObject, 0)
+      ()
     end
 end