/*
    * 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.apache.log4j.chainsaw.helper;
  
  import java.awt.Component;
  import java.awt.Container;
  import java.awt.Dimension;
  import java.awt.EventQueue;
  import java.awt.FileDialog;
  import java.awt.Frame;
  import java.awt.Toolkit;
  import java.awt.event.ActionEvent;
  import java.awt.event.KeyEvent;
  import java.io.File;
  import java.util.ArrayList;
  import java.util.List;
  
  import java.util.Locale;
  import javax.swing.AbstractAction;
  import javax.swing.Action;
  import javax.swing.InputMap;
  import javax.swing.JButton;
  import javax.swing.JComponent;
  import javax.swing.JDialog;
  import javax.swing.JFileChooser;
  import javax.swing.KeyStroke;
  import javax.swing.SwingUtilities;
  
  /**
   * A collection of standard utility methods for use within Swing.
   * 
   * @author Paul Smith <psmith@apache.org>
   *
   */
  public final class SwingHelper {
    /**
     * Centers the Component on screen.
     *
     * @param component
     */
    public static void centerOnScreen(Component component) {
      Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
      component.setLocation(
        (screenSize.width / 2) - (component.getWidth() / 2),
        (screenSize.height / 2) - (component.getHeight() / 2));
    }
    
    /**
     * This method configures a standard Cancel action, bound to the ESC key, to dispose of the dialog,
     * and sets the buttons action to be this action, and adds the action to the dialog's rootPane 
     * action map
     * @param dialog
     * @param cancelButton
     */
    public static void configureCancelForDialog(final JDialog dialog, JButton cancelButton) {
      String CANCEL_ACTION_KEY = "CANCEL_ACTION_KEY";
      int noModifiers = 0;
      KeyStroke escapeKey = KeyStroke.getKeyStroke(KeyEvent.VK_ESCAPE, noModifiers, false);
      InputMap inputMap = dialog.getRootPane().getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT);
      inputMap.put(escapeKey, CANCEL_ACTION_KEY);
      
      Action closeAction = new AbstractAction("Cancel") {
  
        public void actionPerformed(ActionEvent arg0) {
          dialog.dispose();
        }};
      cancelButton.setAction(closeAction);
      dialog.getRootPane().getActionMap().put(CANCEL_ACTION_KEY, closeAction);
      
    }
  
    public static void invokeOnEDT(Runnable runnable) {
      if (EventQueue.isDispatchThread()) {
        runnable.run();
      } else {
        EventQueue.invokeLater(runnable);
      }
    }
  
    public static boolean isMacOSX() {
      return System.getProperty("os.name").toLowerCase(Locale.ENGLISH).startsWith("mac os x");
    }
  
    public static List orderOKCancelButtons(JButton okButton, JButton cancelButton) {
     List result = new ArrayList();
     if (isMacOSX()) {
       result.add(cancelButton);
       result.add(okButton);
     } else {
       result.add(okButton);
       result.add(cancelButton);
     }
     return result;
   }
 
   public static File promptForFile(Container parent, String defaultPath, String title, boolean loadDialog) {
         if (SwingHelper.isMacOSX()) {
             //use filedialog on mac
             Component root = SwingUtilities.getRoot(parent);
             Frame frame = null;
             if (root instanceof Frame) {
               frame = (Frame) root;
             }
 
             FileDialog fileDialog = new FileDialog(frame, title);
             fileDialog.setModal(true);
             fileDialog.setMode(loadDialog ? FileDialog.LOAD : FileDialog.SAVE);
             if (defaultPath != null) {
               fileDialog.setDirectory(defaultPath);
             }
             fileDialog.setVisible(true);
             String fileString = fileDialog.getFile();
             if (fileString == null) {
               return null;
             }
           if (fileDialog.getDirectory() != null) {
             return new File(fileDialog.getDirectory(), fileString);
           } else {
             return new File(fileString);
           }
           } else {
 
                 JFileChooser chooser;
                 if (defaultPath != null) {
                   chooser = new JFileChooser(defaultPath);
                 } else {
                   chooser = new JFileChooser();
                 }
 
                 chooser.setDialogTitle(title);
 
                 chooser.setAcceptAllFileFilterUsed(true);
 
                 int i;
                 if (loadDialog) {
                   i = chooser.showOpenDialog(parent);
                 } else {
                   i = chooser.showSaveDialog(parent);
                 }
 
                 if (i != JFileChooser.APPROVE_OPTION) {
                     return null;
                 }
             return chooser.getSelectedFile();
         }
     }
 }