java/jshell.support/src/org/netbeans/modules/jshell/editor/ConsoleEditor.java - netbeans - Git at Google

 /*
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
  * regarding copyright ownership.  The ASF licenses this file
  * to you under the Apache License, Version 2.0 (the
  * "License"); you may not use this file except in compliance
  * with the License.  You may obtain a copy of the License at
  *
  *   http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing,
  * software distributed under the License is distributed on an
  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  * KIND, either express or implied.  See the License for the
  * specific language governing permissions and limitations
  * under the License.
  */
 package org.netbeans.modules.jshell.editor;

 import com.sun.source.util.Trees;
 import java.awt.Point;
 import java.awt.Rectangle;
 import java.awt.event.ActionEvent;
 import java.beans.PropertyChangeEvent;
 import java.beans.PropertyChangeListener;
 import javax.swing.Action;
 import javax.swing.ImageIcon;
 import javax.swing.JComponent;
 import javax.swing.JEditorPane;
 import javax.swing.JLabel;
 import javax.swing.JLayeredPane;
 import javax.swing.SwingUtilities;
 import javax.swing.event.DocumentEvent;
 import javax.swing.event.DocumentListener;
 import javax.swing.text.BadLocationException;
 import javax.swing.text.Caret;
 import javax.swing.text.Document;
 import javax.swing.text.Position;
 import org.netbeans.api.editor.caret.MoveCaretsOrigin;
 import org.netbeans.api.editor.document.LineDocument;
 import org.netbeans.api.editor.document.LineDocumentUtils;
 import org.netbeans.modules.java.preprocessorbridge.spi.WrapperFactory;
 import org.netbeans.modules.jshell.env.JShellEnvironment;
 import org.netbeans.modules.jshell.env.ShellEvent;
 import org.netbeans.modules.jshell.env.ShellListener;
 import org.netbeans.modules.jshell.env.ShellRegistry;
 import org.netbeans.modules.jshell.env.ShellStatus;
 import org.netbeans.modules.jshell.model.ConsoleEvent;
 import org.netbeans.modules.jshell.model.ConsoleListener;
 import org.netbeans.modules.jshell.model.ConsoleModel;
 import org.netbeans.modules.jshell.model.ConsoleSection;
 import org.netbeans.modules.jshell.model.Rng;
 import org.netbeans.modules.jshell.support.ShellSession;
 import org.netbeans.spi.editor.caret.CascadingNavigationFilter;
 import org.netbeans.spi.editor.caret.NavigationFilterBypass;
 import org.openide.nodes.Node;
 import org.openide.text.CloneableEditor;
 import org.openide.text.CloneableEditorSupport;
 import org.openide.util.Exceptions;
 import org.openide.util.Lookup;
 import org.openide.util.NbBundle;
 import org.openide.windows.TopComponent;

 /**
  *
  * @author sdedic
  */
 @TopComponent.Description(
         preferredID = "JShellEditor",
         iconBase = "org/netbeans/modules/jshell/resources/jshell-terminal.png",
         persistenceType = TopComponent.PERSISTENCE_NEVER
 )
 @TopComponent.Registration(mode = "editor", openAtStartup = false)
 public class ConsoleEditor extends CloneableEditor {

     private ShellSession session;
     private CL cl;
     private Lookup lookup;

     public ConsoleEditor(CloneableEditorSupport support, Lookup lookup) {
         super(support);
         this.lookup = lookup;
     }

     @Override
     protected void componentOpened() {
         super.componentOpened();
     }

     @Override
     protected void componentShowing() {
         super.componentShowing();
         if (session == null) {
             Node n = lookup.lookup(Node.class);
             if (n != null) {
                 getLookup(); // will initialize Lookup
                 setActivatedNodes(new Node[] { n });
             }
             initialize();
             if (session == null && pane != null) {
                 pane.addPropertyChangeListener("document",
                         (e) -> initialize());
             }
         } else {
             updateHourglass();
         }
     }


     @Override
     protected void componentHidden() {
         removeProgressIndicator();
         super.componentHidden();
     }

     private void updateHourglass() {
         ShellStatus status = env.getStatus();

         if (status == ShellStatus.STARTING) {
             showProgressIndicator(prepareInitPanel(), 0, null);
             return;
         } else if (status == ShellStatus.EXECUTE) {
             String label = env.getSession().getExecutionLabel();
             ConsoleModel model = session.getModel();
             ConsoleSection e = model.getExecutingSection();
             if (e != null) {
                 showHourglass(e.getEnd(), label);
                 return;
             }
         }
         removeProgressIndicator();
     }


     @Override
     protected void componentClosed() {
         removeProgressIndicator();
         super.componentClosed();
         pane = null;
         if (cloneableEditorSupport().getOpenedPanes() == null && session != null) {
             try {
                 // terminate the JShell
                 session.getEnv().shutdown();
             } catch (Exception ex) {
                 Exceptions.printStackTrace(ex);
             }
         }
     }

     private JShellEnvironment env;

     private volatile boolean detached;

     private synchronized void detachFromSession() {
         session.getModel().removeConsoleListener(cl);
         cl = null;
         detached = true;
     }

     private void initialize() {
         assert SwingUtilities.isEventDispatchThread();
         JEditorPane pane = getEditorPane();
         if (pane == null) {
             return;
         }
         this.pane = pane;
         Document d = getEditorPane().getDocument();
         ShellSession s  = ShellSession.get(d);

         if (s == null || s == this.session) {
             // some default document, not interesting
             return;
         }
         if (s != this.session && this.session != null) {
             detachFromSession();
         }
         final JShellEnvironment env = ShellRegistry.get().getOwnerEnvironment(s.getConsoleFile());
         this.session = s;

         synchronized (this) {
             detached = false;
             cl = new CL();
             session.getModel().addConsoleListener(cl);
         }
         if (env != null && env != this.env) {
             this.env = env;
             env.addShellListener(cl);
         }

         // post in order to synchronize after initial shell startup
         session.post(() -> {
             SwingUtilities.invokeLater(this::initialResetCaret);
         });

         pane.setNavigationFilter(new NavFilter());

         d.addDocumentListener(new DocumentListener() {
             @Override
             public void insertUpdate(DocumentEvent e) {
                 maybeDiscardEdits();
             }

             @Override
             public void removeUpdate(DocumentEvent e) {
                 maybeDiscardEdits();
             }

             @Override
             public void changedUpdate(DocumentEvent e) {
                 maybeDiscardEdits();
             }
         });
         d.putProperty(WrapperFactory.class, new WrapperFactory() {
             @Override
             public Trees wrapTrees(Trees trees) {
                 return new CompletionFilter(trees);
             }

         });
         SwingUtilities.invokeLater(this::updateHourglass);
     }

     private void initialResetCaret() {
         resetEditableArea(true);
     }

     private void resetEditableArea(boolean caret) {
         if (pane == null || pane.getDocument() == null) {
             // probably closed
             return;
         }

         Document document = pane.getDocument();
         // may block/delay, check detached inside.
         document.render(() -> {
             if (detached) {
                 return;
             }
             final LineDocument ld = LineDocumentUtils.as(document, LineDocument.class);
             if (ld == null) {
                 return;
             }
             ConsoleModel model = session.getModel();
             ConsoleSection input = model.getInputSection();
             if (input != null) {
                 int commandStart = input.getPartBegin();
     //            pane.setCaretPosition(commandStart);
                 if (commandStart > 0 && commandStart < document.getLength()) {
                     return;
                 }
                 if (caret) {
                     pane.setCaretPosition(commandStart);
                 }
             }
         });
     }

     /**
      * Modifies the movement of the caret ot strongly prefer movement within the
      * editable section.
      * If the caret is currently in non-editable section of the console, the filter does nothing
      * When in editable section, and the filter would escape it (either leave input section
      * entirely, or go to a prompt part of it), the filter will catch the caret and
      * <ul>
      * <li>if the caret is already at the first or last row of the input section, pass the navigation on.
      * <li>If the caret goes up or down, magicPosition is used to compute offset at the first/last
      * line of the input section; caret will go to that place.
      * </ul>
      * <ul>
      * <li>if the caret would enter the prompt but remain on the line (i.e. left), the caret will be moved at
      * the end of the preceding line, as if movement was made at the beginning of line.
      * <li>if the caret goes to the start of prompt (begin-line), nothing happens.
      * </ul>
      */
     private class NavFilter extends CascadingNavigationFilter {
         private JEditorPane lastPane;

         @Override
         public void moveDot(FilterBypass fb, int dot, Position.Bias bias) {
             if (handle(fb, dot, bias, true)) {
                 super.moveDot(fb, dot, bias);
             }
         }

         private void setMoveDot(FilterBypass fb, int dot, Position.Bias bias, boolean setOrMove) {
             if (setOrMove) {
                 super.moveDot(fb, dot, bias);
             } else {
                 super.setDot(fb, dot, bias);
             }
         }

         private boolean handle(FilterBypass fb, int dot, Position.Bias bias, boolean setOrMove) {
             // sadly actions must set up a flag in order to be 'compatible':
             JEditorPane p = pane;
             if (p == null) {
                 return true;
             }
             this.lastPane = p;
             if (p.getClientProperty("navigational.action") == null) {
                 if (!(fb instanceof NavigationFilterBypass)) {
                     return true;
                 }
                 MoveCaretsOrigin orig = ((NavigationFilterBypass)fb).getOrigin();
                 if (!MoveCaretsOrigin.DIRECT_NAVIGATION.equals(orig.getActionType())) {
                     return true;
                 }
             }
             int current = fb.getCaret().getDot();
             ConsoleSection input = session.getModel().getInputSection();
             if (input == null) {
                 return true;
             }
             int s = input.getStart();
             int e = input.getEnd();

             try {
                 if (current >= s && current <= e) {
                     // move from within the area
                     if (dot >= s && dot <= e) {
                         return filterWithinSection(input, fb, dot, bias, setOrMove);
                     } else {
                         return filterOutOfSection(input, fb, dot, bias, setOrMove);
                     }
                 }
                 return true;
             } catch (BadLocationException ex) {
                 Exceptions.printStackTrace(ex);
                 // permit to navigate
                 return true;
             }
         }

         /**
          * Handles movement within section. Essentialy just ensures that the caret remains after the prompts.
          * @param fb
          * @param dot
          * @param bias
          * @param setOrMove
          * @return B
          */
         private boolean filterWithinSection(ConsoleSection s, FilterBypass fb, int dot, Position.Bias bias, boolean setOrMove) {
             Caret c = fb.getCaret();
             int curPos = c.getDot();
             LineDocument ld = LineDocumentUtils.as(lastPane.getDocument(), LineDocument.class);
             if (ld == null) {
                 return true;
             }
             int curLine =  LineDocumentUtils.getLineStart(ld, c.getDot());
             int dotLine =  LineDocumentUtils.getLineStart(ld, dot);
             // I want to avoid positioning into the prompts:
             for (Rng range : s.getPartRanges()) {
                 if (range.start > dot) {
                     if (curLine == dotLine) {
                         // if the previous position was also in this range, just relax -
                         // positioned by e.g. mouse, let's do any movement necessary:
                         if (curPos == curLine) {
                             // exception, go to start
                             setMoveDot(fb, range.start, bias, setOrMove);
                             return false;
                         }
                         if (curPos < range.start) {
                             return true;
                         }
                     }
                     if (dot == dotLine) {
                         // jump at the beginning of the line, assuming HOME
                         if (curPos == range.start) {
                             return true;
                         } else {
                             setMoveDot(fb, range.start, bias, setOrMove);
                             return false;
                         }
                     } else if (dotLine == curLine) {
                         // assuming LEFT, WORD-LEFT etc
                         setMoveDot(fb, Math.max(0, dot = dotLine - 1), bias, setOrMove);
                         return false;
                     }
                     setMoveDot(fb, range.start, bias, setOrMove);
                     return false;
                 }
                 if (range.end >= dot) {
                     break;
                 }
             }
             return true;
         }

         private boolean filterOutOfSection(ConsoleSection s, FilterBypass fb, int dot, Position.Bias bias, boolean setOrMove) throws BadLocationException {
             Caret c = fb.getCaret();
             Point magPosition = c.getMagicCaretPosition();
             int curPos = c.getDot();
             if (magPosition == null) {
                 // some other action that move-up / move-down, i.e. start of document / end document, navigation
                 if (curPos == s.getPartBegin()|| curPos == s.getEnd()) {
                     return true;
                 }
                 int nDot;
                 if (dot < s.getPartBegin()&& curPos != s.getStart()) {
                     nDot = s.getPartBegin();
                 } else if (dot > s.getEnd() && curPos != s.getEnd()) {
                     nDot = s.getEnd();
                 } else {
                     return true;
                 }
                 setMoveDot(fb, nDot, bias, setOrMove);
                 return false;
             }

             // magicPosition is set, so the move is accross the lines (in Y axis)
             LineDocument ld = LineDocumentUtils.as(lastPane.getDocument(), LineDocument.class);
             if (ld == null) {
                 return true;
             }
             int curLine =  LineDocumentUtils.getLineStart(ld, c.getDot());
             int ref;
             if (dot < s.getStart()) {
                 // measure Y; get X from magicPosition.
                 ref  = LineDocumentUtils.getLineStart(ld, s.getStart());
             } else if (dot >= s.getEnd()) {
                 ref  = LineDocumentUtils.getLineStart(ld, s.getEnd());
             } else {
                 return true;
             }
             if (curLine == ref) {
                 return true;
             }
             Rectangle rect = lastPane.getUI().modelToView(lastPane, ref);
             rect.x = magPosition.x;
             int pos = lastPane.getUI().viewToModel(lastPane, rect.getLocation());
             if (pos < 0) {
                 return true;
             }
             // I want to avoid positioning into the prompts:
             for (Rng range : s.getPartRanges()) {
                 if (range.start > pos) {
                     pos = range.start;
                     break;
                 }
                 if (range.end >= pos) {
                     break;
                 }
             }
             setMoveDot(fb, pos, bias, setOrMove);
             return false;
         }

         @Override
         public void setDot(FilterBypass fb, int dot, Position.Bias bias) {
             if (handle(fb, dot, bias, false)) {
                 super.setDot(fb, dot, bias);
             }
         }

     }

     private void maybeDiscardEdits() {
         ShellStatus s = env.getStatus();
         ShellSession session = env.getSession();
         if (session == null || session.getModel() == null) {
             return;
         }
         if (session.getModel().isWritingResponse()) {
             OverrideEditorActions.flushUndoQueue(env.getConsoleDocument());
         } else if (s == ShellStatus.INIT || s == ShellStatus.EXECUTE || s == ShellStatus.STARTING) {
             OverrideEditorActions.flushUndoQueue(env.getConsoleDocument());
         }
     }

     private void updateStatusAndActivate() {
         updateHourglass();
         ShellStatus s = env.getStatus();
         if (s == ShellStatus.READY) {
             this.requestVisible();
             OverrideEditorActions.flushUndoQueue(env.getConsoleDocument());
         } else if (s == ShellStatus.EXECUTE) {
             OverrideEditorActions.flushUndoQueue(env.getConsoleDocument());
         }
     }

     private class CL implements ConsoleListener, Runnable, PropertyChangeListener, ShellListener {
         private boolean caret;
         private ShellSession saveSession;

         private CL() {
             this.saveSession = session;
         }

         @Override
         public void shellCreated(ShellEvent ev) {}

         @Override
         public void shellSettingsChanged(ShellEvent ev) {}

         @Override
         public void shellStatusChanged(ShellEvent ev) {
             SwingUtilities.invokeLater(ConsoleEditor.this::updateStatusAndActivate);
         }

         @Override
         public void shellStarted(ShellEvent ev) {
             if (session != env.getSession()) {
                 SwingUtilities.invokeLater(ConsoleEditor.this::initialize);
             }
         }

         @Override
         public void shellShutdown(ShellEvent ev) {
             env.removeShellListener(this);
         }

         @Override
         public void propertyChange(PropertyChangeEvent evt) {
             if (evt.getSource() == session &&
                 ShellSession.PROP_ACTIVE.equals(evt.getPropertyName())) {
                 if (evt.getNewValue() != Boolean.TRUE) {
                     detachFromSession();
                 }
             }
         }

         public void run() {
             if (detached || session != saveSession) {
                 return;
             }
             resetEditableArea(caret);
         }

         @Override
         public void sectionCreated(ConsoleEvent e) {
             if (e.containsInput()) {
                 caret = true;
                 SwingUtilities.invokeLater(this);
             }
         }

         @Override
         public void sectionUpdated(ConsoleEvent e) {
             if (e.containsInput()) {
                 SwingUtilities.invokeLater(this);
             }
         }

         @Override
         public void executing(ConsoleEvent e) {
             SwingUtilities.invokeLater(ConsoleEditor.this::updateHourglass);
         }

         public void closed(ConsoleEvent e) {
             detachFromSession();
         }
     }

     private ExecutingGlassPanel  executeWaitPanel;
     private JLabel  initializingPanel;

     private ExecutingGlassPanel prepareWaitPanel() {
         if (executeWaitPanel == null) {
             ExecutingGlassPanel p = new ExecutingGlassPanel();
             p.addStopListener(this::stopExecution);
             executeWaitPanel = p;
         }
         return executeWaitPanel;
     }

     private JComponent prepareInitPanel() {
         JLabel l = initializingPanel;
         if (initializingPanel == null) {
             l = new JLabel(Bundle.MSG_Initializing(), JLabel.LEADING);
             l.setIcon(new ImageIcon(
                 getClass().getClassLoader().getResource(
                     "org/netbeans/modules/jshell/resources/wait16.gif"
                 )
             ));
             initializingPanel = l;
         }
         return initializingPanel;
     }

     private void stopExecution(ActionEvent e) {
         Action a = pane.getActionMap().get(StopExecutionAction.NAME);
         a.actionPerformed(e);
         /*
         if (session != null) {
             BaseProgressUtils.runOffEventDispatchThread(session::stopExecutingCode,
                     Bundle.LBL_AttemptingStop(), null, false, 100, 2000);
         }
                 */
     }

     private JComponent progressIndicator;

     private JLayeredPane lastLayeredPane;

     private void removeProgressIndicator() {
         if (lastLayeredPane == null || progressIndicator == null) {
             return;
         }
         progressIndicator.setVisible(false);
         JLayeredPane lp = lastLayeredPane;
         lp.remove(progressIndicator);
         lp.repaint();
         progressIndicator = null;

     }

     private void showProgressIndicator(JComponent indicator, int position, String label) {
         removeProgressIndicator();
         try {
             if (pane == null) {
                 return;
             }
             Rectangle r =  pane.getUI().modelToView(pane, position);
             JLayeredPane lp = JLayeredPane.getLayeredPaneAbove(pane);
             if (lp == null) {
                 return;
             }
             if (r == null) {
                 r = new Rectangle(); // 0:0
             }

             lp.add(indicator, JLayeredPane.POPUP_LAYER, 0);
             r.setSize(indicator.getPreferredSize());
             Rectangle converted = SwingUtilities.convertRectangle(
                     pane, r, lp);
             indicator.setBounds(converted);
             indicator.setVisible(true);
             this.lastLayeredPane = lp;
             this.progressIndicator = indicator;
         } catch (BadLocationException ex) {

         }

     }

     @NbBundle.Messages({
             "MSG_Evaluating=Evaluating, please wait...",
             "MSG_Initializing=Loading and initializing Java Shell. Please wait..."
     })
     private void showHourglass(int offset, String label) {
         ExecutingGlassPanel panel = prepareWaitPanel();
         panel.setMessage(label);
         showProgressIndicator(panel, offset + 1, label); // the character AFTER the termianting newline; should be on the next line.
     }

     @Override
     public int getPersistenceType() {
         return PERSISTENCE_NEVER;
     }
 }
	/*
	* Licensed to the Apache Software Foundation (ASF) under one
	* or more contributor license agreements. See the NOTICE file
	* distributed with this work for additional information
	* regarding copyright ownership. The ASF licenses this file
	* to you under the Apache License, Version 2.0 (the
	* "License"); you may not use this file except in compliance
	* with the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing,
	* software distributed under the License is distributed on an
	* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
	* KIND, either express or implied. See the License for the
	* specific language governing permissions and limitations
	* under the License.
	*/
	package org.netbeans.modules.jshell.editor;

	import com.sun.source.util.Trees;
	import java.awt.Point;
	import java.awt.Rectangle;
	import java.awt.event.ActionEvent;
	import java.beans.PropertyChangeEvent;
	import java.beans.PropertyChangeListener;
	import javax.swing.Action;
	import javax.swing.ImageIcon;
	import javax.swing.JComponent;
	import javax.swing.JEditorPane;
	import javax.swing.JLabel;
	import javax.swing.JLayeredPane;
	import javax.swing.SwingUtilities;
	import javax.swing.event.DocumentEvent;
	import javax.swing.event.DocumentListener;
	import javax.swing.text.BadLocationException;
	import javax.swing.text.Caret;
	import javax.swing.text.Document;
	import javax.swing.text.Position;
	import org.netbeans.api.editor.caret.MoveCaretsOrigin;
	import org.netbeans.api.editor.document.LineDocument;
	import org.netbeans.api.editor.document.LineDocumentUtils;
	import org.netbeans.modules.java.preprocessorbridge.spi.WrapperFactory;
	import org.netbeans.modules.jshell.env.JShellEnvironment;
	import org.netbeans.modules.jshell.env.ShellEvent;
	import org.netbeans.modules.jshell.env.ShellListener;
	import org.netbeans.modules.jshell.env.ShellRegistry;
	import org.netbeans.modules.jshell.env.ShellStatus;
	import org.netbeans.modules.jshell.model.ConsoleEvent;
	import org.netbeans.modules.jshell.model.ConsoleListener;
	import org.netbeans.modules.jshell.model.ConsoleModel;
	import org.netbeans.modules.jshell.model.ConsoleSection;
	import org.netbeans.modules.jshell.model.Rng;
	import org.netbeans.modules.jshell.support.ShellSession;
	import org.netbeans.spi.editor.caret.CascadingNavigationFilter;
	import org.netbeans.spi.editor.caret.NavigationFilterBypass;
	import org.openide.nodes.Node;
	import org.openide.text.CloneableEditor;
	import org.openide.text.CloneableEditorSupport;
	import org.openide.util.Exceptions;
	import org.openide.util.Lookup;
	import org.openide.util.NbBundle;
	import org.openide.windows.TopComponent;

	/**
	*
	* @author sdedic
	*/
	@TopComponent.Description(
	preferredID = "JShellEditor",
	iconBase = "org/netbeans/modules/jshell/resources/jshell-terminal.png",
	persistenceType = TopComponent.PERSISTENCE_NEVER
	)
	@TopComponent.Registration(mode = "editor", openAtStartup = false)
	public class ConsoleEditor extends CloneableEditor {

	private ShellSession session;
	private CL cl;
	private Lookup lookup;

	public ConsoleEditor(CloneableEditorSupport support, Lookup lookup) {
	super(support);
	this.lookup = lookup;
	}

	@Override
	protected void componentOpened() {
	super.componentOpened();
	}

	@Override
	protected void componentShowing() {
	super.componentShowing();
	if (session == null) {
	Node n = lookup.lookup(Node.class);
	if (n != null) {
	getLookup(); // will initialize Lookup
	setActivatedNodes(new Node[] { n });
	}
	initialize();
	if (session == null && pane != null) {
	pane.addPropertyChangeListener("document",
	(e) -> initialize());
	}
	} else {
	updateHourglass();
	}
	}


	@Override
	protected void componentHidden() {
	removeProgressIndicator();
	super.componentHidden();
	}

	private void updateHourglass() {
	ShellStatus status = env.getStatus();

	if (status == ShellStatus.STARTING) {
	showProgressIndicator(prepareInitPanel(), 0, null);
	return;
	} else if (status == ShellStatus.EXECUTE) {
	String label = env.getSession().getExecutionLabel();
	ConsoleModel model = session.getModel();
	ConsoleSection e = model.getExecutingSection();
	if (e != null) {
	showHourglass(e.getEnd(), label);
	return;
	}
	}
	removeProgressIndicator();
	}


	@Override
	protected void componentClosed() {
	removeProgressIndicator();
	super.componentClosed();
	pane = null;
	if (cloneableEditorSupport().getOpenedPanes() == null && session != null) {
	try {
	// terminate the JShell
	session.getEnv().shutdown();
	} catch (Exception ex) {
	Exceptions.printStackTrace(ex);
	}
	}
	}

	private JShellEnvironment env;

	private volatile boolean detached;

	private synchronized void detachFromSession() {
	session.getModel().removeConsoleListener(cl);
	cl = null;
	detached = true;
	}

	private void initialize() {
	assert SwingUtilities.isEventDispatchThread();
	JEditorPane pane = getEditorPane();
	if (pane == null) {
	return;
	}
	this.pane = pane;
	Document d = getEditorPane().getDocument();
	ShellSession s = ShellSession.get(d);

	if (s == null \|\| s == this.session) {
	// some default document, not interesting
	return;
	}
	if (s != this.session && this.session != null) {
	detachFromSession();
	}
	final JShellEnvironment env = ShellRegistry.get().getOwnerEnvironment(s.getConsoleFile());
	this.session = s;

	synchronized (this) {
	detached = false;
	cl = new CL();
	session.getModel().addConsoleListener(cl);
	}
	if (env != null && env != this.env) {
	this.env = env;
	env.addShellListener(cl);
	}

	// post in order to synchronize after initial shell startup
	session.post(() -> {
	SwingUtilities.invokeLater(this::initialResetCaret);
	});

	pane.setNavigationFilter(new NavFilter());

	d.addDocumentListener(new DocumentListener() {
	@Override
	public void insertUpdate(DocumentEvent e) {
	maybeDiscardEdits();
	}

	@Override
	public void removeUpdate(DocumentEvent e) {
	maybeDiscardEdits();
	}

	@Override
	public void changedUpdate(DocumentEvent e) {
	maybeDiscardEdits();
	}
	});
	d.putProperty(WrapperFactory.class, new WrapperFactory() {
	@Override
	public Trees wrapTrees(Trees trees) {
	return new CompletionFilter(trees);
	}

	});
	SwingUtilities.invokeLater(this::updateHourglass);
	}

	private void initialResetCaret() {
	resetEditableArea(true);
	}

	private void resetEditableArea(boolean caret) {
	if (pane == null \|\| pane.getDocument() == null) {
	// probably closed
	return;
	}

	Document document = pane.getDocument();
	// may block/delay, check detached inside.
	document.render(() -> {
	if (detached) {
	return;
	}
	final LineDocument ld = LineDocumentUtils.as(document, LineDocument.class);
	if (ld == null) {
	return;
	}
	ConsoleModel model = session.getModel();
	ConsoleSection input = model.getInputSection();
	if (input != null) {
	int commandStart = input.getPartBegin();
	// pane.setCaretPosition(commandStart);
	if (commandStart > 0 && commandStart < document.getLength()) {
	return;
	}
	if (caret) {
	pane.setCaretPosition(commandStart);
	}
	}
	});
	}

	/**
	* Modifies the movement of the caret ot strongly prefer movement within the
	* editable section.
	* If the caret is currently in non-editable section of the console, the filter does nothing
	* When in editable section, and the filter would escape it (either leave input section
	* entirely, or go to a prompt part of it), the filter will catch the caret and
	* <ul>
	* <li>if the caret is already at the first or last row of the input section, pass the navigation on.
	* <li>If the caret goes up or down, magicPosition is used to compute offset at the first/last
	* line of the input section; caret will go to that place.
	* </ul>
	* <ul>
	* <li>if the caret would enter the prompt but remain on the line (i.e. left), the caret will be moved at
	* the end of the preceding line, as if movement was made at the beginning of line.
	* <li>if the caret goes to the start of prompt (begin-line), nothing happens.
	* </ul>
	*/
	private class NavFilter extends CascadingNavigationFilter {
	private JEditorPane lastPane;

	@Override
	public void moveDot(FilterBypass fb, int dot, Position.Bias bias) {
	if (handle(fb, dot, bias, true)) {
	super.moveDot(fb, dot, bias);
	}
	}

	private void setMoveDot(FilterBypass fb, int dot, Position.Bias bias, boolean setOrMove) {
	if (setOrMove) {
	super.moveDot(fb, dot, bias);
	} else {
	super.setDot(fb, dot, bias);
	}
	}

	private boolean handle(FilterBypass fb, int dot, Position.Bias bias, boolean setOrMove) {
	// sadly actions must set up a flag in order to be 'compatible':
	JEditorPane p = pane;
	if (p == null) {
	return true;
	}
	this.lastPane = p;
	if (p.getClientProperty("navigational.action") == null) {
	if (!(fb instanceof NavigationFilterBypass)) {
	return true;
	}
	MoveCaretsOrigin orig = ((NavigationFilterBypass)fb).getOrigin();
	if (!MoveCaretsOrigin.DIRECT_NAVIGATION.equals(orig.getActionType())) {
	return true;
	}
	}
	int current = fb.getCaret().getDot();
	ConsoleSection input = session.getModel().getInputSection();
	if (input == null) {
	return true;
	}
	int s = input.getStart();
	int e = input.getEnd();

	try {
	if (current >= s && current <= e) {
	// move from within the area
	if (dot >= s && dot <= e) {
	return filterWithinSection(input, fb, dot, bias, setOrMove);
	} else {
	return filterOutOfSection(input, fb, dot, bias, setOrMove);
	}
	}
	return true;
	} catch (BadLocationException ex) {
	Exceptions.printStackTrace(ex);
	// permit to navigate
	return true;
	}
	}

	/**
	* Handles movement within section. Essentialy just ensures that the caret remains after the prompts.
	* @param fb
	* @param dot
	* @param bias
	* @param setOrMove
	* @return B
	*/
	private boolean filterWithinSection(ConsoleSection s, FilterBypass fb, int dot, Position.Bias bias, boolean setOrMove) {
	Caret c = fb.getCaret();
	int curPos = c.getDot();
	LineDocument ld = LineDocumentUtils.as(lastPane.getDocument(), LineDocument.class);
	if (ld == null) {
	return true;
	}
	int curLine = LineDocumentUtils.getLineStart(ld, c.getDot());
	int dotLine = LineDocumentUtils.getLineStart(ld, dot);
	// I want to avoid positioning into the prompts:
	for (Rng range : s.getPartRanges()) {
	if (range.start > dot) {
	if (curLine == dotLine) {
	// if the previous position was also in this range, just relax -
	// positioned by e.g. mouse, let's do any movement necessary:
	if (curPos == curLine) {
	// exception, go to start
	setMoveDot(fb, range.start, bias, setOrMove);
	return false;
	}
	if (curPos < range.start) {
	return true;
	}
	}
	if (dot == dotLine) {
	// jump at the beginning of the line, assuming HOME
	if (curPos == range.start) {
	return true;
	} else {
	setMoveDot(fb, range.start, bias, setOrMove);
	return false;
	}
	} else if (dotLine == curLine) {
	// assuming LEFT, WORD-LEFT etc
	setMoveDot(fb, Math.max(0, dot = dotLine - 1), bias, setOrMove);
	return false;
	}
	setMoveDot(fb, range.start, bias, setOrMove);
	return false;
	}
	if (range.end >= dot) {
	break;
	}
	}
	return true;
	}

	private boolean filterOutOfSection(ConsoleSection s, FilterBypass fb, int dot, Position.Bias bias, boolean setOrMove) throws BadLocationException {
	Caret c = fb.getCaret();
	Point magPosition = c.getMagicCaretPosition();
	int curPos = c.getDot();
	if (magPosition == null) {
	// some other action that move-up / move-down, i.e. start of document / end document, navigation
	if (curPos == s.getPartBegin()\|\| curPos == s.getEnd()) {
	return true;
	}
	int nDot;
	if (dot < s.getPartBegin()&& curPos != s.getStart()) {
	nDot = s.getPartBegin();
	} else if (dot > s.getEnd() && curPos != s.getEnd()) {
	nDot = s.getEnd();
	} else {
	return true;
	}
	setMoveDot(fb, nDot, bias, setOrMove);
	return false;
	}

	// magicPosition is set, so the move is accross the lines (in Y axis)
	LineDocument ld = LineDocumentUtils.as(lastPane.getDocument(), LineDocument.class);
	if (ld == null) {
	return true;
	}
	int curLine = LineDocumentUtils.getLineStart(ld, c.getDot());
	int ref;
	if (dot < s.getStart()) {
	// measure Y; get X from magicPosition.
	ref = LineDocumentUtils.getLineStart(ld, s.getStart());
	} else if (dot >= s.getEnd()) {
	ref = LineDocumentUtils.getLineStart(ld, s.getEnd());
	} else {
	return true;
	}
	if (curLine == ref) {
	return true;
	}
	Rectangle rect = lastPane.getUI().modelToView(lastPane, ref);
	rect.x = magPosition.x;
	int pos = lastPane.getUI().viewToModel(lastPane, rect.getLocation());
	if (pos < 0) {
	return true;
	}
	// I want to avoid positioning into the prompts:
	for (Rng range : s.getPartRanges()) {
	if (range.start > pos) {
	pos = range.start;
	break;
	}
	if (range.end >= pos) {
	break;
	}
	}
	setMoveDot(fb, pos, bias, setOrMove);
	return false;
	}

	@Override
	public void setDot(FilterBypass fb, int dot, Position.Bias bias) {
	if (handle(fb, dot, bias, false)) {
	super.setDot(fb, dot, bias);
	}
	}

	}

	private void maybeDiscardEdits() {
	ShellStatus s = env.getStatus();
	ShellSession session = env.getSession();
	if (session == null \|\| session.getModel() == null) {
	return;
	}
	if (session.getModel().isWritingResponse()) {
	OverrideEditorActions.flushUndoQueue(env.getConsoleDocument());
	} else if (s == ShellStatus.INIT \|\| s == ShellStatus.EXECUTE \|\| s == ShellStatus.STARTING) {
	OverrideEditorActions.flushUndoQueue(env.getConsoleDocument());
	}
	}

	private void updateStatusAndActivate() {
	updateHourglass();
	ShellStatus s = env.getStatus();
	if (s == ShellStatus.READY) {
	this.requestVisible();
	OverrideEditorActions.flushUndoQueue(env.getConsoleDocument());
	} else if (s == ShellStatus.EXECUTE) {
	OverrideEditorActions.flushUndoQueue(env.getConsoleDocument());
	}
	}

	private class CL implements ConsoleListener, Runnable, PropertyChangeListener, ShellListener {
	private boolean caret;
	private ShellSession saveSession;

	private CL() {
	this.saveSession = session;
	}

	@Override
	public void shellCreated(ShellEvent ev) {}

	@Override
	public void shellSettingsChanged(ShellEvent ev) {}

	@Override
	public void shellStatusChanged(ShellEvent ev) {
	SwingUtilities.invokeLater(ConsoleEditor.this::updateStatusAndActivate);
	}

	@Override
	public void shellStarted(ShellEvent ev) {
	if (session != env.getSession()) {
	SwingUtilities.invokeLater(ConsoleEditor.this::initialize);
	}
	}

	@Override
	public void shellShutdown(ShellEvent ev) {
	env.removeShellListener(this);
	}

	@Override
	public void propertyChange(PropertyChangeEvent evt) {
	if (evt.getSource() == session &&
	ShellSession.PROP_ACTIVE.equals(evt.getPropertyName())) {
	if (evt.getNewValue() != Boolean.TRUE) {
	detachFromSession();
	}
	}
	}

	public void run() {
	if (detached \|\| session != saveSession) {
	return;
	}
	resetEditableArea(caret);
	}

	@Override
	public void sectionCreated(ConsoleEvent e) {
	if (e.containsInput()) {
	caret = true;
	SwingUtilities.invokeLater(this);
	}
	}

	@Override
	public void sectionUpdated(ConsoleEvent e) {
	if (e.containsInput()) {
	SwingUtilities.invokeLater(this);
	}
	}

	@Override
	public void executing(ConsoleEvent e) {
	SwingUtilities.invokeLater(ConsoleEditor.this::updateHourglass);
	}

	public void closed(ConsoleEvent e) {
	detachFromSession();
	}
	}

	private ExecutingGlassPanel executeWaitPanel;
	private JLabel initializingPanel;

	private ExecutingGlassPanel prepareWaitPanel() {
	if (executeWaitPanel == null) {
	ExecutingGlassPanel p = new ExecutingGlassPanel();
	p.addStopListener(this::stopExecution);
	executeWaitPanel = p;
	}
	return executeWaitPanel;
	}

	private JComponent prepareInitPanel() {
	JLabel l = initializingPanel;
	if (initializingPanel == null) {
	l = new JLabel(Bundle.MSG_Initializing(), JLabel.LEADING);
	l.setIcon(new ImageIcon(
	getClass().getClassLoader().getResource(
	"org/netbeans/modules/jshell/resources/wait16.gif"
	)
	));
	initializingPanel = l;
	}
	return initializingPanel;
	}

	private void stopExecution(ActionEvent e) {
	Action a = pane.getActionMap().get(StopExecutionAction.NAME);
	a.actionPerformed(e);
	/*
	if (session != null) {
	BaseProgressUtils.runOffEventDispatchThread(session::stopExecutingCode,
	Bundle.LBL_AttemptingStop(), null, false, 100, 2000);
	}
	*/
	}

	private JComponent progressIndicator;

	private JLayeredPane lastLayeredPane;

	private void removeProgressIndicator() {
	if (lastLayeredPane == null \|\| progressIndicator == null) {
	return;
	}
	progressIndicator.setVisible(false);
	JLayeredPane lp = lastLayeredPane;
	lp.remove(progressIndicator);
	lp.repaint();
	progressIndicator = null;

	}

	private void showProgressIndicator(JComponent indicator, int position, String label) {
	removeProgressIndicator();
	try {
	if (pane == null) {
	return;
	}
	Rectangle r = pane.getUI().modelToView(pane, position);
	JLayeredPane lp = JLayeredPane.getLayeredPaneAbove(pane);
	if (lp == null) {
	return;
	}
	if (r == null) {
	r = new Rectangle(); // 0:0
	}

	lp.add(indicator, JLayeredPane.POPUP_LAYER, 0);
	r.setSize(indicator.getPreferredSize());
	Rectangle converted = SwingUtilities.convertRectangle(
	pane, r, lp);
	indicator.setBounds(converted);
	indicator.setVisible(true);
	this.lastLayeredPane = lp;
	this.progressIndicator = indicator;
	} catch (BadLocationException ex) {

	}

	}

	@NbBundle.Messages({
	"MSG_Evaluating=Evaluating, please wait...",
	"MSG_Initializing=Loading and initializing Java Shell. Please wait..."
	})
	private void showHourglass(int offset, String label) {
	ExecutingGlassPanel panel = prepareWaitPanel();
	panel.setMessage(label);
	showProgressIndicator(panel, offset + 1, label); // the character AFTER the termianting newline; should be on the next line.
	}

	@Override
	public int getPersistenceType() {
	return PERSISTENCE_NEVER;
	}
	}