/**
 * Calculator
 * A shareware calculator
 *
 * @author {@link http://blog.csdn.net/hongweijin Bingbing Li}
 *
 * @recitation 0101 Matt Carlson
 *
 * @date 12/7/2005 12:08AM
 *
 */
 
 import javax.swing.*;
 import javax.swing.border.*;
 import java.awt.*;
 import java.awt.event.*;
 
 public class Calculator extends JFrame implements ActionListener
 {
     public static final int WIDTH = 800;            // width of the window                  
     public static final int HEIGHT = 600;           // height of the window                 
     public static final int BUTTON_WIDTH = 80;      // width of the buttons                 
     public static final int BUTTON_HEIGHT = 60;     // height of the buttons                
                                                                                             
     private CardLayout dealer;                      // card layout                          
     private JPanel        deckPanel;                   // used to card layout                  
                                                                                             
     private JTextField result;                      // the calculate result                 
     private JCheckBoxMenuItem scientificMode;       // the menu item of the mode            
                                                                                             
     private Box vPanel1;                            // the first line buttons of the        
                                                        // scientific mode.                     
                                                                                             
     private JButton mod;                            // the modular button                   
     private JButton xey;                            // the button of Yth root of X          
     private JButton ms;                             // save button                          
    private JButton mr;                             // release the stored value             
     private    JButton mc;                             // clear the stored value               
                                                                                             
     private double head = 0.0;                      // the first number of the equation     
     private double tail = 0.0;                      // the second number of the equation    
                                                                                             
     private boolean substitution = true;            // whether substituted the answer or not
                                                                                             
     private String operatedCommand = 'NOTHING';     // the current operated command         
     private String preOperatedCommand = 'NOTHING';  // remember the pre-operated command
     
     private double variableMemory = 0.0;            // the variable of the memory
     
     private JButton jButtonR;                       // the register's button
     private JButton jButtonE;                       // the edit's button
     
     private JTextField nameField;                   // the field of the name
     private JTextField countryField;                // the field of the country
     private JTextField zipField;                    // the field of the zip
     private JTextField stateField;                  // the field of the state
     private JTextField cityField ;                  // the field of the city
     private JTextField streetAddressField;          // the field of the address
     
     private JTextField first;                       // the first part of the key
     private JTextField second;                      // the second part of the key
     private JTextField third;                       // the third part of the key
     private JTextField fourth;                      // the fourth part of the key
     
     
     public Calculator()
     {
         setSize(WIDTH, HEIGHT);
         setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         setTitle('Normal Calculator');
         
         Container contentPre = getContentPane();    // the container of the window
         
         dealer = new CardLayout();                  // create a new card layout
         deckPanel = new JPanel();                    
         deckPanel.setLayout(dealer);
         
         Box content = Box.createVerticalBox();      // create a new vertical Box 
         
         Box registration = Box.createVerticalBox();
         
         /****************************************************
         *    menu
         *   file
         *****************************************************/
         JMenu fileMenu = new JMenu('File');         
         JMenuItem exitItemOfFile = new JMenuItem('Exit');
         exitItemOfFile.addActionListener(this);
         fileMenu.add(exitItemOfFile);
         /**
         *    menu
         *   settings
         */
         JMenu settingsMenu = new JMenu('Settings');
         JMenuItem registrationInfo = new JMenuItem('Registration Info');
         registrationInfo.addActionListener(this);
         settingsMenu.add(registrationInfo);
         
         scientificMode = new JCheckBoxMenuItem('Scientific Mode');
         scientificMode.addActionListener(this);
         settingsMenu.add(scientificMode);
         
         JMenuBar jMenuBar = new JMenuBar();
         jMenuBar.add(fileMenu);
         jMenuBar.add(settingsMenu);
         setJMenuBar(jMenuBar);
         
         /****************************************************
         *    textFiled panel
        *****************************************************/
        
        result = new JTextField('0');                     // the initiated value of the answer
        result.setBackground(Color.CYAN);                 // set the back ground color with cyan
        result.setHorizontalAlignment(JTextField.RIGHT);  // set the horizontal alignment  
        
        
        content.add(result);
             
         content.add(paintButtons());
         
         deckPanel.add('cal', content);                    // add the calculators card to the layout
         
         registration.add(paintRegistration());            // add the register window
         
         deckPanel.add('reg', registration);               // add the register window to the layout
         
         contentPre.add(deckPanel);                   // add the cards to the container
     }
     
     /**
     * paint the buttons of the two models.
     *
     */
     public Box paintButtons() 
     {
         /****************************************************
        *    Buttons
        *****************************************************/
        
         /**
         *    line1
         */ 
         vPanel1 = Box.createVerticalBox();                                      
         
         // add the backwards's button                                                                           
         JButton backwards = new JButton('1/X');                                     
         backwards.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));       
         backwards.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));     
         backwards.addActionListener(this);                                          
         vPanel1.add(backwards);    
                                                          
         // add the factorial button                                                                            
         JButton factorial = new JButton('X!');                                      
         factorial.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));       
         factorial.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));     
         factorial.addActionListener(this);                                          
         vPanel1.add(factorial);                                                     
         
         // add the square's button                                                                            
         JButton square = new JButton('<html>X<sup>2</sup></html>');                 
         square.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));          
         square.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));        
         square.addActionListener(this);
         square.setActionCommand('sqr');                                             
         vPanel1.add(square);                                                        
         
         // add the square root's button                                                                            
         JButton squareRoot = new JButton('\u221a');                                 
         squareRoot.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));      
         squareRoot.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));    
         squareRoot.addActionListener(this);                                         
         vPanel1.add(squareRoot);                                                    
               
         // add the power's button                                                                       
         JButton power = new JButton('<html>X<sup>Y</sup></html>');                  
         power.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));           
         power.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));         
         power.addActionListener(this);   
         power.setActionCommand('pow');                                           
         vPanel1.add(power);                                                         
                  
         /**
         *    line2
         */
         Box vPanel2 = Box.createVerticalBox();
         
         // add the modular button 
         mod = new JButton('Mod');
         mod.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         mod.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         mod.addActionListener(this);
         vPanel2.add(mod);
                  
         // add the seven button 
         JButton seven = new JButton('7');
         seven.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         seven.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         seven.addActionListener(this);
         vPanel2.add(seven); 
         
         // add the four button 
         JButton four = new JButton('4');
         four.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         four.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         four.addActionListener(this);
         vPanel2.add(four); 
         
         // add the one button 
         JButton one = new JButton('1');
         one.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         one.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         one.addActionListener(this);
         vPanel2.add(one); 
         
         // add the zero button 
         JButton zero = new JButton('0');
         zero.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         zero.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         zero.addActionListener(this);
         vPanel2.add(zero);
         
         /**
         *    line3
         */
         Box vPanel3 = Box.createVerticalBox();
         
         // add the Yth root of X button 
         xey = new JButton('XeY');
         xey.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         xey.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         xey.addActionListener(this);
         vPanel3.add(xey);
              
          // add the eight button 
         JButton eight = new JButton('8');
         eight.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
        eight.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         eight.addActionListener(this);
         vPanel3.add(eight); 
         
         // add the five button 
         JButton five = new JButton('5');
         five.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         five.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         five.addActionListener(this);
         vPanel3.add(five); 
         
         // add the two button 
         JButton two = new JButton('2');
         two.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         two.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         two.addActionListener(this);
         vPanel3.add(two); 
         
         // add the dot button 
         JButton dot = new JButton('.');
         dot.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         dot.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         dot.addActionListener(this);
         vPanel3.add(dot);      
         
         /**
         *    line4
         */
         Box vPanel4 = Box.createVerticalBox();
         
         // add the MS button 
         ms = new JButton('MS');
         ms.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
        ms.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         ms.addActionListener(this);
         vPanel4.add(ms);
             
         // add the nine button 
         JButton nine = new JButton('9');
         nine.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         nine.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         nine.addActionListener(this);
         vPanel4.add(nine); 
         
         // add the six button 
         JButton six = new JButton('6');
         six.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         six.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         six.addActionListener(this);
         vPanel4.add(six); 
         
         // add the three button 
         JButton three = new JButton('3');
         three.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         three.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         three.addActionListener(this);
         vPanel4.add(three); 
         
         // add the plusMinus button 
         JButton plusMinus = new JButton('\u00b1');
         plusMinus.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         plusMinus.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         plusMinus.addActionListener(this);
         vPanel4.add(plusMinus);     
         
         /**
         *    line5
         */
         Box vPanel5 = Box.createVerticalBox();
         
         // add the MR button 
         mr = new JButton('MR');
         mr.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         mr.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         mr.addActionListener(this);
         vPanel5.add(mr);
         
         // add the division button 
         JButton division = new JButton('\u00F7');
         division.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         division.setPreferredSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));
         division.addActionListener(this);
         vPanel5.add(division); 
         
         // add the multiplication button 
         JButton multiplication = new JButton('\u00d7');
         multiplication.setMaximumSize(new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT));