/*
 * A Java Applet that animates B-Trees
 * Copyright (C) 2002 Uday Bondhugula
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
 * USA.
 *
 */

import java.applet.*; 
import java.awt.*; 
import java.awt.event.*;
import javax.swing.*;

public class TreeApplet extends Applet	{ 
    Panel controlPane; 
    ButtonGroup cbg; 
    JTextField keyField; 
    MyCanvas canvas; 
    JTextArea displayArea; 
    Panel subControlPane1, subControlPane3; 
    Thread runner;
    int key;
    JButton nextButton, prevButton; 
    Image arrow, treePicture;
    DocPanel docp; 

    public void init()	{
        MediaTracker tracker = new MediaTracker(this);
        arrow = getImage(getCodeBase(), "ARROW_3D.gif"); 
        treePicture = getImage(getCodeBase(), "tree-picture.gif");
        tracker.addImage(arrow, 0);
        tracker.addImage(treePicture, 1);
        try	{
            showStatus("Loading Images ...");
            tracker.waitForID(0);
            tracker.waitForID(1);
        } catch (InterruptedException e)	{}
        showStatus("Finished loading images");
        setForeground(Color.black); 
        setBackground(Color.white); 
        setLayout(new BorderLayout()); 

        Panel header = new Panel(); 
        header.setBackground(MyCanvas.gold); 
        header.add(new JLabel("2-3-4  Trees")); 
        add(header, BorderLayout.NORTH); 

        Panel drawingPane = new Panel(); 
        drawingPane.setLayout(new BorderLayout());
        canvas = new MyCanvas(this); 
        drawingPane.add(canvas); 
        add(drawingPane, BorderLayout.CENTER); 

        controlPane = new Panel();
        controlPane.setLayout(new GridLayout(2, 1)); 
        controlPane.setForeground(Color.black); 
        // controlPane.setBackground(Color.lightGray); 

        subControlPane1 = new Panel();
        // subControlPane1.setBackground(Color.lightGray); 

        GridBagLayout gridbag = new GridBagLayout(); 
        GridBagConstraints c = new GridBagConstraints(); 
        subControlPane1.setLayout(gridbag); 

        c.fill = GridBagConstraints.BOTH; 

        c.weightx = 0.0;
        c.gridwidth = GridBagConstraints.REMAINDER;
        JLabel mode = new JLabel("Select Mode: "); 
        gridbag.setConstraints(mode, c); 
        subControlPane1.add(mode); 
        cbg = new ButtonGroup(); 
        makeCheckbox("Single step", gridbag, c); 
        makeCheckbox("Run", gridbag, c); 
        makeCheckbox("Step by step", gridbag, c); 
        c.gridwidth = 1;
        makebutton("Prev step", subControlPane1);
        gridbag.setConstraints(prevButton, c);
        c.gridwidth = GridBagConstraints.REMAINDER; 
        makebutton("Next step", subControlPane1);
        gridbag.setConstraints(nextButton, c);

        Panel subControlPane2 = new Panel()	{
            public Insets getInsets()	{
                return new Insets(25, 0, 0, 0);
            }
        };

        subControlPane2.setLayout(gridbag);
        //subControlPane2.setBackground(Color.lightGray);
        c.weightx = 1.0;
        c.gridwidth = 1;
        JLabel l = new JLabel("  Enter key value: ");
        gridbag.setConstraints(l, c); 
        subControlPane2.add(l); 
        c.gridwidth = GridBagConstraints.REMAINDER; 
        keyField = new JTextField(0); 
        keyField.setBackground(Color.white); 
        keyField.setForeground(Color.black); 
        gridbag.setConstraints(keyField, c); 
        subControlPane2.add(keyField);
        gridbag.setConstraints(subControlPane2, c); 
        subControlPane1.add(subControlPane2); 
        controlPane.add(subControlPane1);

        subControlPane3 = new Panel();
        //subControlPane3.setBackground(Color.lightGray);
        subControlPane3.setLayout(new GridLayout(5, 1)); 
        makebutton("Insert", subControlPane3); 
        makebutton("Delete", subControlPane3); 
        makebutton("Search", subControlPane3); 
        makebutton("Reset", subControlPane3); 
        makebutton("Exit", subControlPane3); 

        controlPane.add(subControlPane3); 
        controlPane.setSize(100, 800); 
        add(controlPane, BorderLayout.EAST); 

        Panel display = new Panel(); 
        display.setLayout(new BorderLayout()); 
        displayArea = new JTextArea(4, 50);
        displayArea.setEditable(false); 
        displayArea.setBackground(new Color(255, 255, 235)); 
        displayArea.setForeground(Color.black); 
        displayArea.setFont(new Font("Helvetica", Font.BOLD, 11)); 
        JScrollPane jsp = new JScrollPane(displayArea,
                JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
                JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);


        docp = new DocPanel(displayArea); 
        displayArea.setText(docp.whatNext);
        display.add(docp, BorderLayout.WEST); 
        display.add(jsp, BorderLayout.CENTER); 
        add(display, BorderLayout.SOUTH); 
    } 


    protected void makebutton(String name, Panel panel) { 
        JButton button = new JButton(name); 
        button.addActionListener(canvas); 
        //button.setBackground(Color.lightGray); 
        button.setForeground(Color.black); 
        if (name.equals("Prev step"))		{ 
            button.setEnabled(false); 
            prevButton = button;
        } 
        if (name.equals("Next step"))		{ 
            nextButton = button; 
            button.setEnabled(false); 
        } 
        panel.add(button); 
    } 

    protected void makeCheckbox(String name, GridBagLayout gridbag, GridBagConstraints c) { 
        JRadioButton cbox = new JRadioButton(name, false); 
        if (name.equals("Single step"))	cbox.setSelected(true); 
        gridbag.setConstraints(cbox, c);
        //cbox.setBackground(Color.lightGray); 
        cbox.setForeground(Color.black);
        cbox.addItemListener(canvas);
        subControlPane1.add(cbox);
        cbg.add(cbox);
    }


    public Insets getInsets()	{
        return new Insets(10, 10, 10, 10);
    }

    public void start()	{}
    public void stop()	{
        if (canvas.runner != null)	canvas.runner = null;
    }
}