package bluej.utility.javafx;

import bluej.utility.Debug;
import javafx.embed.swing.SwingNode;
import javafx.event.EventHandler;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;
import threadchecker.OnThread;
import threadchecker.Tag;

import java.awt.AWTEvent;
import java.awt.Component;
import java.awt.EventQueue;
import java.awt.Toolkit;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.security.AccessController;
import java.security.PrivilegedAction;




| In SwingNode, there is a SwingKeyEventHandler class which translates
| FX keypresses into Swing keypresses.  Unfortunately it has a bug,
| wherein AltGr shortcuts on Windows (which are used frequently by
| some non-English users) do not work correctly.  This is bug:<p>
|
| Https://bugs.openjdk.java.net/browse/JDK-8088471
|
| <p>And currently has no fix date.  Thankfully, a commenter on the bug
| pointed to a solution: overriding the handler to suppress modifiers
| on a particular event.
|
| <p>So this class is a near-copy of SwingNode.SwingKeyEventHandler,
| with that suggested fix.  Since some of the fields and classes we are
| using are private or package-private, we have to use reflection
| to access them.  Not nice, but I can't see any other way to do it.
|
@OnThread(Tag.FXPlatform)
public class SwingKeyEventHandlerFixed implements EventHandler<KeyEvent>{    
   private final SwingNode swingNode;
   
   private Field lwFrameField;

   @OnThread(Tag.Any)
   
   public SwingKeyEventHandlerFixed(SwingNode swingNode)
   {        
      this.swingNode = swingNode;
       
      try
       {
         lwFrameField = SwingNode.class.getDeclaredField("lwFrame");
         lwFrameField.setAccessible(true);         
         }
       
      catch (NoSuchFieldException e)
       {
         e.printStackTrace();         
         }     
      }

   
   @Override
   
   public void handle(javafx.scene.input.KeyEvent event)
   {        
      try
       {
         handleSub(event);         
         }
       
      catch (Exception e)
       {
         Debug.reportError(e);         
         }     
      }

   
   public void handleSub(javafx.scene.input.KeyEvent event) throws IllegalAccessException, ClassNotFoundException, NoSuchMethodException, InvocationTargetException
   {
      Component frame = (Component) lwFrameField.get(swingNode);
      if (frame == null) {            
         return;         
         }
      if (event.getCharacter().isEmpty()) {            
         
         return;         
         }
       
      
      if (event.getCode() == KeyCode.LEFT  ||
      event.getCode() == KeyCode.RIGHT ||
      event.getCode() == KeyCode.UP ||
      event.getCode() == KeyCode.DOWN ||
      event.getCode() == KeyCode.TAB)
       {
         event.consume();         
         }

      Method fxKeyEventTypeToKeyID = Class.forName("javafx.embed.swing.SwingEvents").getDeclaredMethod("fxKeyEventTypeToKeyID", javafx.scene.input.KeyEvent.class);
      fxKeyEventTypeToKeyID.setAccessible(true);

      int swingID = (Integer)fxKeyEventTypeToKeyID.invoke(null, event);
      if (swingID < 0) {            
         return;         
         }

      Method fxKeyModsToKeyMods = Class.forName("javafx.embed.swing.SwingEvents").getDeclaredMethod("fxKeyModsToKeyMods", javafx.scene.input.KeyEvent.class);
      fxKeyModsToKeyMods.setAccessible(true);

      int swingModifiers = (Integer)fxKeyModsToKeyMods.invoke(null, event);
      int swingKeyCode = event.getCode().getCode();
      char swingChar = event.getCharacter().charAt(0);

       
      
      
      if (event.getEventType() == javafx.scene.input.KeyEvent.KEY_PRESSED) {
         String text = event.getText();
         if (text.length() == 1) {
            swingChar = text.charAt(0);             
            }         
         }
       
      
      
      if (event.getEventType() == KeyEvent.KEY_TYPED && event.isAltDown() && event.isControlDown())
       {            
         swingModifiers = 0;         
         }

      long swingWhen = System.currentTimeMillis();
       
      java.awt.event.KeyEvent keyEvent = new java.awt.event.KeyEvent(
           
      frame, swingID, swingWhen, swingModifiers,
           
      swingKeyCode, swingChar);
       
      AccessController.doPrivileged(new PostEventAction(keyEvent));     
      }

   
   private static class PostEventAction implements PrivilegedAction<Void>
   {        
      private AWTEvent event;
       
      public PostEventAction(AWTEvent event)
{                     
this.event = event;         
         }
       
      @Override
      @OnThread(value = Tag.FXPlatform, ignoreParent = true)
       
      public Void run()
{         
EventQueue eq = Toolkit.getDefaultToolkit().getSystemEventQueue();
         eq.postEvent(event);
           
         return null;         
         }     
      } 
   }