package com.cpex.javafx.util;

import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Skin;
import javafx.scene.control.TextInputControl;
import javafx.stage.Window;
import javafx.stage.WindowEvent;

import com.sun.javafx.scene.control.skin.TextInputControlSkin;

public class FxBugs
{

   public static void installMemoryLeakWorkaround(TextInputControl control)
   {
      TextControlMemoryLeakWorkaround workaround = new TextControlMemoryLeakWorkaround(control);
      workaround.install();
   }

   private static class TextControlMemoryLeakWorkaround implements ChangeListener, EventHandler<WindowEvent>
   {
      private final TextInputControl control;
      
      private Scene scene;

      private Window window;
      
      public TextControlMemoryLeakWorkaround(TextInputControl control)
      {
         this.control = control;
         scene = null;
         window = null;
      }

      public void install()
      {
         control.sceneProperty().addListener(this);
         setScene(control.getScene());
      }

      @Override
      public void changed(ObservableValue observable, Object oldValue, Object newValue)
      {
         if (observable == control.sceneProperty())
         {
            setScene(control.getScene());
         }
         else if (scene != null && observable == scene.windowProperty())
         {
            setWindow(scene.getWindow());
         }
      }

      @Override
      public void handle(WindowEvent event)
      {
         applyWorkaround();
      }

      private void setScene(Scene scene)
      {
         if (this.scene != scene)
         {
            Window window = null;

            if (this.scene != null)
            {
               this.scene.windowProperty().removeListener(this);
            }

            this.scene = scene;

            if (this.scene != null)
            {
               this.scene.windowProperty().addListener(this);
            }

            setWindow(window);
         }
      }

      private void setWindow(Window window)
      {
         if (this.window != window)
         {
            boolean hadWindow = false;
            if (this.window != null)
            {
               this.window.removeEventFilter(WindowEvent.WINDOW_HIDING, this);
               hadWindow = true;
            }

            this.window = window;

            if (this.window != null)
            {
               this.window.addEventFilter(WindowEvent.WINDOW_HIDING, this);
            }
            else if (hadWindow)
            {
               applyWorkaround();
            }
         }
      }

      private void applyWorkaround()
      {
         Skin<?> skin = control.getSkin();
         if (skin instanceof TextInputControlSkin)
         {
            TextInputControlSkin ticSkin = (TextInputControlSkin) skin;

            try
            {
               ticSkin.setCaretAnimating(false);
            }
            catch (Exception e)
            {
               // ignored
            }

            try
            {
               ticSkin.dispose();
            }
            catch (Exception e)
            {
               // ignored
            }
         }
      }
   } // end class TextControlMemoryLeakWorkaround

   private FxBugs()
   {
      // empty
   }

}