// Simplified P5 with one button for addition
// Author: Irena Pevac
// Date: Nov 23, 2013
// Project: Calculator
// Event driven programming
import java.text.DecimalFormat;
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;

public class Calculator extends JApplet implements ActionListener
{
private String text1,text2,textResult;
private JLabel label,labelEast,labelWest, labelResult;
private JButton buttonPlus, buttonSubtract, buttonMultiply, buttonDivide, buttonModulo;
private JTextField t1, t2;
private JPanel panel, northPanel, midPanel, eastPanel, westPanel,
southPanel;
private int  n1, n2, nResult;
private double one,two,Result;
private Font f = new Font("Arial", Font.BOLD, 22);

public void init()
{
BorderLayout bLayout = new BorderLayout();
GridLayout gLayout = new GridLayout(4,1);
panel = new JPanel();
panel.setLayout(bLayout);
        text1 = "";
        text2 = "";
textResult = "";
        t1 = new JTextField(10);
t1.setFont(new Font("Arial", Font.BOLD, 16));
t1.setText(text1);
        t2 = new JTextField(10);
t2.setFont(new Font("Arial", Font.BOLD, 16));
t2.setText(text2);
label = new JLabel("Type in two integer numbers and " +
                           "press operation to calculate result.");
labelEast = new JLabel( " Enter number2 ");
labelWest = new JLabel( " Enter number1 ");
labelResult = new JLabel(" Result:                    ");
labelResult.setFont(f);

northPanel = new JPanel();
northPanel.setPreferredSize(new Dimension ( 500, 50));
eastPanel = new JPanel();
eastPanel.setPreferredSize(new Dimension ( 200, 100));
westPanel = new JPanel();
westPanel.setPreferredSize(new Dimension ( 200, 100));
midPanel = new JPanel();
midPanel.setPreferredSize(new Dimension ( 100, 100));
midPanel.setBackground(Color.yellow);
southPanel = new JPanel();
southPanel.setPreferredSize(new Dimension ( 500, 250));

eastPanel.add(labelEast);
eastPanel.add(t2);
westPanel.add(labelWest);
westPanel.add(t1);
northPanel.add(label);
southPanel.add(labelResult);

midPanel.setLayout(new BoxLayout(midPanel, BoxLayout.Y_AXIS));
buttonPlus = (new JButton(" + "));
buttonPlus.setFont(f);
buttonPlus.setAlignmentX(Component.CENTER_ALIGNMENT);
buttonPlus.setAlignmentY(Component.CENTER_ALIGNMENT);
midPanel.add(buttonPlus);
buttonSubtract = (new JButton(" - "));
buttonSubtract.setFont(f);
buttonSubtract.setAlignmentX(Component.CENTER_ALIGNMENT);
buttonSubtract.setAlignmentY(Component.CENTER_ALIGNMENT);
midPanel.add(buttonSubtract);
buttonMultiply= (new JButton(" * "));
buttonMultiply.setFont(f);
buttonMultiply.setAlignmentX(Component.CENTER_ALIGNMENT);
buttonMultiply.setAlignmentY(Component.CENTER_ALIGNMENT);
midPanel.add(buttonMultiply);
buttonDivide= (new JButton(" / "));
buttonDivide.setFont(f);
buttonDivide.setAlignmentX(Component.CENTER_ALIGNMENT);
buttonDivide.setAlignmentY(Component.CENTER_ALIGNMENT);
midPanel.add(buttonDivide);
buttonModulo= (new JButton(" % "));
buttonModulo.setFont(f);
buttonModulo.setAlignmentX(Component.CENTER_ALIGNMENT);
buttonModulo.setAlignmentY(Component.CENTER_ALIGNMENT);
midPanel.add(buttonModulo);

panel.add(northPanel, BorderLayout.NORTH);
panel.add(southPanel, BorderLayout.SOUTH);
panel.add(eastPanel, BorderLayout.EAST);
panel.add(westPanel, BorderLayout.WEST);
panel.add(midPanel, BorderLayout.CENTER);

buttonPlus.addActionListener(this);
buttonSubtract.addActionListener(this);
buttonMultiply.addActionListener(this);
buttonDivide.addActionListener(this);
buttonModulo.addActionListener(this);
add(panel);
t1.setFocusable(true);
    }

public void actionPerformed(ActionEvent e)
    {
        if (e.getSource() == buttonPlus)
        {
             text1 = t1.getText();
             n1 = Integer.parseInt(text1);
             text2 = t2.getText();
             n2 = Integer.parseInt(text2);
             nResult = n1+n2;
             labelResult.setText( "RESULT:  " + text1 + " + " + text2 + " = " + nResult);
        }
        if(e.getSource()== buttonSubtract)
        {
                 text1 = t1.getText();
                 n1 = Integer.parseInt(text1);
                 text2 = t2.getText();
                 n2 = Integer.parseInt(text2);
                 nResult = n1-n2;
                 labelResult.setText( "RESULT:  " + text1 + " - " + text2 + " = " + nResult);
        }
        if(e.getSource()== buttonMultiply)
        {
                 text1 = t1.getText();
                 n1 = Integer.parseInt(text1);
                 text2 = t2.getText();
                 n2 = Integer.parseInt(text2);
                 nResult = n1*n2;
                 labelResult.setText( "RESULT:  " + text1 + " * " + text2 + " = " + nResult);
        }
        if(e.getSource()== buttonDivide)
        {
                 DecimalFormat twoDForm = new DecimalFormat("#.##");
                 text1 = t1.getText();
                 one = Double.parseDouble(text1);
                 text2 = t2.getText();
                 two = Double.parseDouble(text2);
                 Result = one/two;
                 labelResult.setText( "RESULT:  " + text1 + " / " + text2 + " = " + twoDForm.format(Result));
        }
        if(e.getSource()== buttonModulo)
        {
                 text1 = t1.getText();
                 n1 = Integer.parseInt(text1);
                 text2 = t2.getText();
                 n2 = Integer.parseInt(text2);
                 nResult = n1%n2;
                 labelResult.setText( "RESULT:  " + text1 + " % " + text2 + " = " + nResult);
        }
    }
}