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

public class StaffingProgram extends JFrame
{
	private JLabel resultAL, resultBL, resultCL, outputAL, outputBL, outputCL;
	private JTextField resultATF, resultBTF, resultCTF, outputATF, outputBTF, outputCTF;
	private JButton calculateB, exitB;
	private CalculateButtonHandler cbHandler;
	private ExitButtonHandler ebHandler;
	

	private static final int WIDTH = 900;
	private static final int HEIGHT = 600;

	public StaffingProgram()
	{
	
		
		resultAL = new JLabel("Please enter the number of employees presently on duty at location A: ", 
			SwingConstants.RIGHT);
		resultBL = new JLabel("Please enter the number of employees presently on duty at location B: ",
			SwingConstants.RIGHT);
		resultCL = new JLabel("Please enter the number of employees presently on duty at location C: ",
			SwingConstants.RIGHT);
		outputAL = new JLabel("Number of employees under or over for location A: ",
			SwingConstants.RIGHT);
		outputBL = new JLabel("Number of employees under or over for location B: ",
			SwingConstants.RIGHT);
		outputCL = new JLabel("Number of employees under or over for location C: ",
			SwingConstants.RIGHT);
		
		
		
		
		
		
		resultATF = new JTextField(10);
		resultBTF = new JTextField(10);
		resultCTF = new JTextField(10);
		outputATF = new JTextField(10);
		outputBTF = new JTextField(10);
		outputCTF = new JTextField(10);
		
		
		

		calculateB = new JButton("Calculate");
		cbHandler = new CalculateButtonHandler();
		calculateB.addActionListener(cbHandler);

		exitB = new JButton("Exit");
		ebHandler = new ExitButtonHandler();
		exitB.addActionListener(ebHandler);
		

		setTitle("Staffing Level Calculations");

		Container pane = getContentPane();

		pane.setLayout(new GridLayout(7, 2));

		
		pane.add(resultAL);
		pane.add(resultATF);
		pane.add(resultBL);
		pane.add(resultBTF);
		pane.add(resultCL);
		pane.add(resultCTF);
		pane.add(outputAL);
		pane.add(outputATF);
		pane.add(outputBL);
		pane.add(outputBTF);
		pane.add(outputCL);
		pane.add(outputCTF);
		pane.add(calculateB);
		pane.add(exitB);

		setSize(WIDTH, HEIGHT);
		setVisible(true);
		setDefaultCloseOperation(EXIT_ON_CLOSE);
	}

	private class CalculateButtonHandler implements ActionListener
	{
		public void actionPerformed(ActionEvent e)
		{
			double resulta, resultb, resultc;
			
			
			resulta = Double.parseDouble(resultATF.getText());
			resultb = Double.parseDouble(resultBTF.getText());
			resultc = Double.parseDouble(resultCTF.getText());
			
	try
	{
			if (resulta > 5)
			{resulta = resulta - 5;
			outputATF.setText("You are overstaffed by " + resulta);}
			if (resulta < 5)
			{resulta = 5 - resulta;
			outputATF.setText("You are understaffed by " + resulta);}
			if (resulta == 5)
			{outputATF.setText("Your staffing is sufficient");}
			
			
			if (resultb > 8){
			resultb = resultb - 8;
			outputBTF.setText("You are overstaffed by " + resultb);
			}
			if (resultb < 8){
			resultb = 8 - resultb;
			outputBTF.setText("You are understaffed by " + resultb);
			}
			if (resultb == 8){
			outputBTF.setText("Your staffing is sufficient");
			}
			
						

			if (resultc > 10){
			resultc = resultc - 10;
			outputCTF.setText("You are overstaffed by " + resultc);
			}
			if (resultc < 10){
			resultc = 10 - resultc;
			outputCTF.setText("You are understaffed by " + resultc);
			}
			if (resultc == 10){
			outputCTF.setText("Your staffing is sufficient");
			}

			else
			{
			throw new TheException(); //calls
            		}
	}
			catch (TheException ev)
        		{
            		outputATF.setText("" +ev + " You must enter a number");
       			}

		}
	}


class TheException extends Exception
{
	public String toString()
	{
		return "Illegal";
	}
}



	private class ExitButtonHandler implements ActionListener
	{
		public void actionPerformed(ActionEvent e)
		{
			System.exit(0);
		}
	}
	
	public static void main(String[] args) throws IOException
	{
		StaffingProgram rectObject = new StaffingProgram();
	}
}