/**
 * Program for Calculating Progressive Income Tax
 *
 * @author tkrogers
 * @version 10-14-11
 */
import java.awt.* ;
import java.awt.event.* ;
import javax.swing.* ;
 
// Do not alter the following code ///////////////////////////////////////////////////////////////////////
public class ProgressiveIncomeTax extends JPanel implements ActionListener {
    private JTextField  input ;
    private JTextArea  output ;
    private int             onSwitch1,
                                onSwitch2 ;                  
    private double      incomeDollars,
                                taxableIncome,
                                tax1,
                                tax2,
                                totalTax,
                                nominalTaxRate ;
   
    public static void main ( ) {
 
        createAndShowGUI ( ) ;
    }
 
    // constructor
    public ProgressiveIncomeTax ( ) {        
        setLayout( new GridLayout ( 2,1 ) ) ;          
        input = new JTextField( "   Enter income in $ ", 40 ) ;        
        input.addActionListener ( this ) ;          
        output = new JTextArea ( "  Income " + incomeDollars + "\n",5, 40  ) ;        
        output.setEditable ( false ) ;        
        JScrollPane scrollPane = new JScrollPane ( input ) ;                
        add ( scrollPane ) ; 
        add ( output ) ;          
    }
 
    // Creates a graphical user interface.
    private static void createAndShowGUI ( ) {        
        JFrame frame = new JFrame ( "Progressive Tax Calculator" ) ;        
        frame.setDefaultCloseOperation ( JFrame.EXIT_ON_CLOSE ) ;          
        // Add contents to the window.        
        frame.add(new ProgressiveIncomeTax ( ) ) ;          
        // Displays the window.        
        frame.pack ( ) ;        
        frame.setVisible ( true ) ;    
    }
 
    // Outputs results when <enter> is pressed after inputting an income.
    public void actionPerformed ( ActionEvent e ) {
        String s = input.getText ( ) ;
        s = s.substring ( 21 ).trim ( ) ;
        incomeDollars = Double.parseDouble ( s ) ;
        input.setText ( "   Enter income in $ " ) ;
        calculateTax ( ) ;
        output.setText ( "  Income $" + incomeDollars +
                         "\n  Taxable Income $" + taxableIncome +
                         "\n  Total Tax $" + totalTax +
                         "\n  Nominal Tax Rate " + nominalTaxRate + "%" ) ;
    }
 
    // Sets the number of decmal places show for doubles and rounds appropriately.
    public double decimalPlaces ( int decimals, double x) {
        double d = Math.pow ( 10, decimals ) ;
        x = ( ( int ) ( (x + 0.5 / d ) * d ) ) / d  ;
        return x ;
    }
 
    //Calculates the tax
    public void calculateTax ( ) {
        taxableIncome = ( incomeDollars - 19999.99 )  * onSwitch1 ( ) ;
        taxableIncome = decimalPlaces ( 2, taxableIncome ) ;
        tax1 = taxableIncome *.25 ;
        tax2 = ( taxableIncome -10000 ) * 0.10 * onSwitch2 ( ) ;
        totalTax = tax1 + tax2 ;
        roundUpTax ( ) ;
        calculateNominalTaxRate ( ) ;
    }
// Complete the code shown below. Do not alter the above code.
/////////////////////////////////////////////////////////////////////////////////////////////////////
 
    //Calculates the on-switch for the 1st tax rate.
    public int onSwitch1 ( ) {
    // Add the required code.  
        return 0 ;
    }
 
    //Calculates the the on-switch for the 2nd tax rate.
    public int onSwitch2 ( ) {
    // Add the required code.
        return s ;
    }
 
    // Rounds tenths of cents upward
    public void roundUpTax ( ) {
    // Add the required code.
    }
 
    //Calculates the the nominal tax rate.
    public void calculateNominalTaxRate ( ) {
    // Add the required code.    
    }
}