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

public class CarGUI extends JFrame implements ActionListener {
    private Car		car;
    private DecimalFormat	format	= new DecimalFormat("######.0###");
    
    // GUI  components
    private JLabel lblDrive = null;
    private JLabel lblInTank = null;
    private JTextField txtDrive = null;
    private JButton btnDrive = null;
    private JButton btnFill = null;
    
    /**
     * Answers a GUI for the Car object
     * @param Car  c   the Car object
     **/
    
    public CarGUI(Car c) {
        super(c.getCarName());
        car = c;
        // init gui stuff
        lblDrive = new JLabel("Miles to Drive: ");
        lblInTank = new JLabel("Left in Tank: " + car.getFuelInTank());
        txtDrive = new JTextField(5);
        btnDrive = new JButton("Drive");
        btnFill	 = new JButton("Fill Up");
        
        setupLayout();
 	setDefaultCloseOperation(EXIT_ON_CLOSE);
    }
    
    /**
     * Encapsulates the layout of the GUI
     **/
    public void setupLayout() {
        Container c = getContentPane();
        c.setLayout(new FlowLayout());
        c.add(lblDrive);
        c.add(txtDrive);
        c.add(btnDrive);
        c.add(btnFill);
        c.add(lblInTank);
        
        btnDrive.addActionListener(this);
        btnFill.addActionListener(this);
        
        setSize(250, 100);
        setLocation(100, 100);
        setVisible(true);
    }
    
    /**
     * Responds to button clicks
     * @param ActionEvent e  the event (button click)
     *
     **/
    public void actionPerformed(ActionEvent e) {
        if (e.getSource() == btnDrive) {
            if (txtDrive.getText().trim().compareTo("") != 0){
                double d = Double.parseDouble( txtDrive.getText());
                car.drive(d);
                
                lblInTank.setText("Left in Tank: " +
                format.format(car.getFuelInTank()));
                txtDrive.setText("");
            }
        } else if(e.getSource() == btnFill) {
            car.fillTank();
            lblInTank.setText("Left in Tank: " +
            car.getFuelInTank());
        }
    }
    
    public static void main(String args[]) {
        CarGUI cg1 = new CarGUI(new Car("Ford Mustang"));
        CarGUI cg2 = new CarGUI(new Car("Honda Accord", 35, 12));
    }
}