//
// FILE:     AddingFrame.java
// AUTHOR:   Stuart Reges 
// DATE:     1999/08/27
// COMMENT:  Class AddingFrame provides the user interface
//           for a graphical adding machine.
//
// MODIFIED: 2012/09/10 by Eugene Wallingford
// CHANGE:   Updated constructor
//                   to name the window for CS 2530.
//           Changed updateDisplay()
//                   to send the accumulator a displayValue() message.
//           Changed constructor
//                   to use class that implements an interface.
//

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

public class AddingFrame extends CloseableFrame
{
  private Accumulator myAccumulator;  // accumulator for math
  private JTextField  myText;         // text display
  
  public AddingFrame()
  {
    // create frame and accumulator
    setSize(200, 250);
    setTitle("CS 2530 Adder");
    Container contentPane = getContentPane();
    myAccumulator = new BasicAccumulator();
 
    // create and add text field for current display
    myText = new JTextField("0", 20);
    contentPane.add(myText, "North");
    myText.setHorizontalAlignment(JTextField.RIGHT);
  
    // create and add button panel for adding machine
    JPanel buttons = createButtonPanel();
    contentPane.add(buttons, "Center");
  
    // create and add clear button at the bottom
    JButton clear = new JButton("Clear");
    clear.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e)
      {
        myAccumulator.clear();
        updateDisplay();
      }
    });
    contentPane.add(clear, "South");
  }

  private JPanel createButtonPanel()
  // post: creates a panel of buttons with digits placed as
  //       in an adding machine, with minus and plus buttons
  //       surrounding 0 in the bottom row.  Adds listeners
  //       to each button to modify accumulator and update
  //       the display.
  {
    JPanel buttons = new JPanel();
    buttons.setLayout(new GridLayout(4, 3));
    digitButton(buttons, 7);
    digitButton(buttons, 8);
    digitButton(buttons, 9);
    digitButton(buttons, 4);
    digitButton(buttons, 5);
    digitButton(buttons, 6);
    digitButton(buttons, 1);
    digitButton(buttons, 2);
    digitButton(buttons, 3);
    JButton minus = new JButton("-");
    minus.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e)
      {
        myAccumulator.minus();
        updateDisplay();
      }
    });
    buttons.add(minus);
    digitButton(buttons, 0);
    JButton plus = new JButton("+");
    plus.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e)
      {
        myAccumulator.plus();
        updateDisplay();
      }
    });
    buttons.add(plus);
    return buttons;
  }
  
  private void digitButton(JPanel buttons, final int value)
  // post: adds a single digit button to the buttons panel
  //       and adds a listener that calls the accumulator
  //       with that digit value.
  {
    JButton b = new JButton("" + value);
    b.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e)
      {
        myAccumulator.addDigit(value);
        updateDisplay();
      }
    });
    buttons.add(b);
  }
  
  private void updateDisplay()
  // post: updates the text display to the current display
  //       value returned by the accumulator
  {
    myText.setText("" + myAccumulator.displayValue());
  }
}