package jsetool.gui;

import java.awt.*;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.*;

import javax.swing.*;
import javax.swing.border.BevelBorder;

/**
 * @author Mike Lawson
 * 
 * @since Oct 29, 2004
 * 
 * The FSMEditingPane class allows the user to enter a FSM graphically. It
 * includes a toolbar and a pane on which to draw the FSM.
 * 
 *  
 */
public class FSMEditingPane extends JPanel
{

  protected FSMDrawingPane drawingPane;

  protected JScrollPane    scroll = null;

  /**
   * Constructs a new finite state machine editing pane.
   */
  public FSMEditingPane()
  {
    configureDisplay();
  }

  /**
   * Returns the labeled state the user has selected to be the initial state
   * 
   * @return LabeledState
   */
  public LabeledState getInitialState()
  {
    return drawingPane.getInitialState();
  }

  /**
   * Reads the drawing pane from the given file name.
   * 
   * @param file
   * @throws Exception
   */
  public void readDrawingPane(File file) throws Exception
  {
    File saveFile = file;

    FileInputStream fis = new FileInputStream(saveFile);

    ObjectInputStream ois = new ObjectInputStream(fis);

    drawingPane = (FSMDrawingPane) ois.readObject();
    scroll.setViewportView(drawingPane);
  }

  /**
   * Clears all the objects out of the drawing.
   */
  public void resetObjects()
  {
    drawingPane.resetObjects();

  }

  /**
   * Saves the drawing pane to the given file name.
   * 
   * @param file
   * @throws Exception
   */
  public void saveDrawingPane(File file) throws Exception
  {
    File saveFile = file;
    FileOutputStream fos = new FileOutputStream(saveFile);

    ObjectOutputStream oos = new ObjectOutputStream(fos);

    oos.writeObject(drawingPane);
  }

  /*
   * (non-Javadoc)
   * 
   * @see jsetool.gui.DrawingPane#configureDisplay()
   */
  protected void configureDisplay()
  {
    setLayout(new BorderLayout());
    
    JPanel buttonPanel = createButtonPanel();
    // put the button panel on the left hand side of the panel 
    JPanel tempPanel = new JPanel();
    tempPanel.setLayout(new BorderLayout());
    tempPanel.add(buttonPanel, BorderLayout.WEST);
    tempPanel.setBorder(new BevelBorder(0));
    add(tempPanel, BorderLayout.NORTH);

    drawingPane = new FSMDrawingPane();
    
    scroll = new JScrollPane(drawingPane);
    scroll.setPreferredSize(new Dimension(200, 200));
    scroll.setAutoscrolls(true);
    scroll.setBorder(new BevelBorder(0));
    add(scroll, BorderLayout.CENTER);

  }

  /**
   * Clears the current diagram.
   *  
   */
  public void clearDiagram()
  {
    drawingPane = new FSMDrawingPane();
    scroll.setViewportView(drawingPane);
  }

  /**
   * Prompts the user for a file to read and reads it.
   *  
   */
  protected void promptAndReadDrawing()
  {
    try
    {
      JFileChooser fc = new JFileChooser();
      int retval = fc.showOpenDialog(this);
      if (retval == JFileChooser.APPROVE_OPTION)
      {
        readDrawingPane(fc.getSelectedFile());
      }

    }
    catch (Exception e)
    {
      e.printStackTrace();
      JOptionPane.showMessageDialog(this, "Failed to load drawing", "Error Reading", JOptionPane.ERROR_MESSAGE);
    }

  }

  /**
   * Prompts the user for a file to write to and writes it.
   *  
   */
  protected void promptAndSaveDrawing()
  {
    try
    {
      JFileChooser fc = new JFileChooser();
      int retval = fc.showSaveDialog(this);
      if (retval == JFileChooser.APPROVE_OPTION)
      {
        saveDrawingPane(fc.getSelectedFile());
      }

    }
    catch (Exception e)
    {
      e.printStackTrace();
      JOptionPane.showMessageDialog(this, "Failed to save drawing", "Error Saving", JOptionPane.ERROR_MESSAGE);
    }
  }

  /**
   * Creates the panel that shows the drawing tools. The panel is assumed to be
   * drawn top to bottom.
   * 
   * @return JPanel
   */
  private JPanel createButtonPanel()
  {
    JPanel buttonPanel = new JPanel();

    JButton newStateButton = makeStateButton();

    buttonPanel.add(newStateButton);

    JButton drawEdgeButton = makeEdgeButton();
    buttonPanel.add(drawEdgeButton);

    // Normal Operations Button
    JButton normalOpsButton = makeNormalOpsButton();
    buttonPanel.add(normalOpsButton);

    JButton saveButton = makeSaveButton();
    buttonPanel.add(saveButton);

    JButton loadButton = makeLoadButton();
    buttonPanel.add(loadButton);

    JButton clearButton = makeClearButton();
   
    buttonPanel.add(clearButton);
    
    return buttonPanel;

  }
  
  /**
   * @return
   */
  private JButton makeButton(String imagePath, String defaultText)
  {
    ImageIcon icon = getImageIcon(imagePath);
    
    JButton button = null;
    if (icon == null)
    {
      button = new JButton(defaultText);
    }
    else
    {
      Image img = icon.getImage();
      icon.setImage(img.getScaledInstance(12, 12, Image.SCALE_SMOOTH));
      button = new JButton(icon);
      button.setPreferredSize(new Dimension(24, 24));
      button.setToolTipText(defaultText);
    }
    
    return button;
  }

  /**
   * @return
   */
  private JButton makeClearButton()
  {
    JButton clearButton = makeButton("images/new.gif", "Clear");
    
    clearButton.addActionListener(new ActionListener()
    {
      public void actionPerformed(ActionEvent e)
      {
        clearDiagram();
      }
    });
    return clearButton;
  }

  /**
   * @return
   */
  private JButton makeLoadButton()
  {
    //  Load Button
    JButton loadButton = makeButton("images/open.gif", "Load");
    loadButton.addActionListener(new ActionListener()
    {

      public void actionPerformed(ActionEvent e)
      {
        promptAndReadDrawing();

      }

    });
    return loadButton;
  }

  /**
   * @return
   */
  private JButton makeSaveButton()
  {
    // Save Button
    JButton saveButton = makeButton("images/save.gif", "Save");
    saveButton.addActionListener(new ActionListener()
    {

      public void actionPerformed(ActionEvent e)
      {
        promptAndSaveDrawing();

      }

    });
    return saveButton;
  }

  /**
   * @return
   */
  private JButton makeNormalOpsButton()
  {
    JButton normalOpsButton = makeButton("images/Select.gif", "Select");
    
    normalOpsButton.addActionListener(new ActionListener()
    {

      public void actionPerformed(ActionEvent e)
      {
        drawingPane.drawingNormalOpsSelected();

      }

    });
    return normalOpsButton;
  }

  

  /**
   * @return
   */
  private JButton makeEdgeButton()
  {
    JButton drawEdgeButton = makeButton("images/BlueArrow.gif", "Connect");
    drawEdgeButton.addActionListener(new ActionListener()
    {

      public void actionPerformed(ActionEvent e)
      {
        drawingPane.drawingEdgeToolSelected();

      }

    });
    return drawEdgeButton;
  }

  /**
   * @return
   */
  private JButton makeStateButton()
  {
    // New State Button
    JButton newStateButton = makeButton("images/State.gif", "State");
    newStateButton.addActionListener(new ActionListener()
    {

      public void actionPerformed(ActionEvent e)
      {
        drawingPane.drawingStateToolSelected();

      }

    });
    return newStateButton;
  }

  private ImageIcon getImageIcon(String path)
  {
    int MAX_IMAGE_SIZE = 2400;  //Change this to the size of
                                 //your biggest image, in bytes.
    int count = 0;
    
    BufferedInputStream imgStream = new BufferedInputStream(
       this.getClass().getResourceAsStream(path));
    
    if (imgStream != null) {
        byte buf[] = new byte[MAX_IMAGE_SIZE];
        try {
            count = imgStream.read(buf);
            imgStream.close();
        } catch (java.io.IOException ioe) {
            System.err.println("Couldn't read stream from file: " + path);
            ioe.printStackTrace();
            return null;
        }
        if (count <= 0) {
            System.err.println("Empty file: " + path);
            return null;
        }
        return new ImageIcon(Toolkit.getDefaultToolkit().createImage(buf));
    } else {
        System.err.println("Couldn't find file: " + path);
        return null;
    }
  }
}