////////////////////////////////////////////////////////////////////////////////
   // checkstyle: Checks Java source code for adherence to a set of rules.
   // Copyright (C) 2001-2019 the original author or authors.
   //
   // This library is free software; you can redistribute it and/or
   // modify it under the terms of the GNU Lesser General Public
   // License as published by the Free Software Foundation; either
   // version 2.1 of the License, or (at your option) any later version.
   //
  // This library is distributed in the hope that it will be useful,
  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  // Lesser General Public License for more details.
  //
  // You should have received a copy of the GNU Lesser General Public
  // License along with this library; if not, write to the Free Software
  // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  ////////////////////////////////////////////////////////////////////////////////
  
  package com.puppycrawl.tools.checkstyle.gui;
  
  import java.awt.BorderLayout;
  import java.awt.GridLayout;
  import java.awt.event.ActionEvent;
  import java.awt.event.KeyEvent;
  import java.io.File;
  
  import javax.swing.AbstractAction;
  import javax.swing.BorderFactory;
  import javax.swing.JButton;
  import javax.swing.JComboBox;
  import javax.swing.JFileChooser;
  import javax.swing.JFrame;
  import javax.swing.JLabel;
  import javax.swing.JOptionPane;
  import javax.swing.JPanel;
  import javax.swing.JScrollPane;
  import javax.swing.JSplitPane;
  import javax.swing.JTextArea;
  import javax.swing.SwingConstants;
  import javax.swing.filechooser.FileFilter;
  
  import com.puppycrawl.tools.checkstyle.api.CheckstyleException;
  import com.puppycrawl.tools.checkstyle.gui.MainFrameModel.ParseMode;
  
  /**
   * Displays information about a parse tree.
   * The user can change the file that is parsed and displayed
   * using a JFileChooser.
   *
   * @noinspection MagicNumber
   */
  public class MainFrame extends JFrame {
  
      private static final long serialVersionUID = 7970053543351871890L;
  
      /** Checkstyle frame model. */
      private final transient MainFrameModel model = new MainFrameModel();
      /** Reload action. */
      private final ReloadAction reloadAction = new ReloadAction();
      /** Code text area. */
      private JTextArea textArea;
      /** Tree table. */
      private TreeTable treeTable;
  
      /** Create a new MainFrame. */
      public MainFrame() {
          createContent();
      }
  
      /** Create content of this MainFrame. */
      private void createContent() {
          setLayout(new BorderLayout());
  
          textArea = new JTextArea(20, 15);
          textArea.setEditable(false);
          final JScrollPane textAreaScrollPane = new JScrollPane(textArea);
  
          treeTable = new TreeTable(model.getParseTreeTableModel());
          treeTable.setEditor(textArea);
          treeTable.setLinePositionMap(model.getLinesToPosition());
          final JScrollPane treeTableScrollPane = new JScrollPane(treeTable);
  
          final JSplitPane splitPane = new JSplitPane(JSplitPane.VERTICAL_SPLIT, treeTableScrollPane,
              textAreaScrollPane);
          add(splitPane, BorderLayout.CENTER);
          splitPane.setResizeWeight(0.7);
  
          add(createButtonsPanel(), BorderLayout.PAGE_END);
  
          pack();
      }
  
      /**
       * Create buttons panel.
       * @return buttons panel.
       */
      private JPanel createButtonsPanel() {
          final JButton openFileButton = new JButton(new FileSelectionAction());
         openFileButton.setMnemonic(KeyEvent.VK_S);
         openFileButton.setText("Open File");
 
         reloadAction.setEnabled(false);
         final JButton reloadFileButton = new JButton(reloadAction);
         reloadFileButton.setMnemonic(KeyEvent.VK_R);
         reloadFileButton.setText("Reload File");
 
         final JComboBox<ParseMode> modesCombobox = new JComboBox<>(ParseMode.values());
         modesCombobox.setSelectedIndex(0);
         modesCombobox.addActionListener(event -> {
             model.setParseMode((ParseMode) modesCombobox.getSelectedItem());
             reloadAction.actionPerformed(null);
         });
 
         final JLabel modesLabel = new JLabel("Modes:", SwingConstants.RIGHT);
         final int leftIndentation = 10;
         modesLabel.setBorder(BorderFactory.createEmptyBorder(0, leftIndentation, 0, 0));
 
         final JPanel buttonPanel = new JPanel();
         buttonPanel.setLayout(new GridLayout(1, 2));
         buttonPanel.add(openFileButton);
         buttonPanel.add(reloadFileButton);
 
         final JPanel modesPanel = new JPanel();
         modesPanel.add(modesLabel);
         modesPanel.add(modesCombobox);
 
         final JPanel mainPanel = new JPanel();
         mainPanel.setLayout(new BorderLayout());
         mainPanel.add(buttonPanel);
         mainPanel.add(modesPanel, BorderLayout.LINE_END);
 
         return mainPanel;
     }
 
     /**
      * Open file and load it.
      * @param sourceFile the file to open.
      */
     public void openFile(File sourceFile) {
         try {
             model.openFile(sourceFile);
             setTitle(model.getTitle());
             reloadAction.setEnabled(model.isReloadActionEnabled());
             textArea.setText(model.getText());
             treeTable.setLinePositionMap(model.getLinesToPosition());
         }
         catch (final CheckstyleException ex) {
             JOptionPane.showMessageDialog(this, ex.getMessage());
         }
     }
 
     /**
      * Handler for file selection action events.
      */
     private class FileSelectionAction extends AbstractAction {
 
         private static final long serialVersionUID = 1762396148873280589L;
 
         @Override
         public void actionPerformed(ActionEvent event) {
             final JFileChooser fileChooser = new JFileChooser(model.getLastDirectory());
             final FileFilter filter = new JavaFileFilter();
             fileChooser.setFileFilter(filter);
 
             final int returnCode = fileChooser.showOpenDialog(MainFrame.this);
             if (returnCode == JFileChooser.APPROVE_OPTION) {
                 final File file = fileChooser.getSelectedFile();
                 openFile(file);
             }
         }
 
     }
 
     /**
      * Handler for reload action events.
      */
     private class ReloadAction extends AbstractAction {
 
         private static final long serialVersionUID = -890320994114628011L;
 
         @Override
         public void actionPerformed(ActionEvent event) {
             openFile(model.getCurrentFile());
         }
 
     }
 
     /**
      * Filter for Java files.
      */
     private static class JavaFileFilter extends FileFilter {
 
         @Override
         public boolean accept(File file) {
             return MainFrameModel.shouldAcceptFile(file);
         }
 
         @Override
         public String getDescription() {
             return "Java Source File";
         }
 
     }
 
 }