import java.awt.Component;
import java.awt.Dimension;
import java.awt.Image;
import java.net.URL;

import javax.swing.ImageIcon;
import javax.swing.JButton;

public final class UIHelper
{
    public static JButton createButton(String text)
    {
        JButton button = new JButton(text);
        button.setFocusPainted(true);
        button.setBorderPainted(true);
        button.setContentAreaFilled(true);
        return button;
    }

    public static JButton createButton(String text, String icon)
    {
        return createButton(text, icon, false);
    }

    public static JButton createButton(String text, String icon, boolean flat)
    {
        ImageIcon iconNormal = readImageIcon(icon + ".png");
        ImageIcon iconHighlight = readImageIcon(icon + "_highlight.png");
        ImageIcon iconPressed = readImageIcon(icon + "_pressed.png");

        JButton button = new JButton(text, iconNormal);
        button.setFocusPainted(!flat);
        button.setBorderPainted(!flat);
        button.setContentAreaFilled(!flat);
        if (iconHighlight != null) 
        {
            button.setRolloverEnabled(true);
            button.setRolloverIcon(iconHighlight);
        }
        if (iconPressed != null)
            button.setPressedIcon(iconPressed);
        return button;
    }

    public static void centerOnScreen(Component component)
    {
        Dimension paneSize = component.getSize();
        Dimension screenSize = component.getToolkit().getScreenSize();
        component.setLocation(
            (screenSize.width - paneSize.width) / 2,
            (screenSize.height - paneSize.height) / 2);
    }

    public static ImageIcon readImageIcon(String fileName)
    {
        Image image = readImage(fileName);
        if (image == null)
            return null;

        return new ImageIcon(image);
    }

    public static Image readImage(String fileName)
    {
        URL url = UIHelper.class.getResource("images/" + fileName);
        if (url == null)
            return null;

        return java.awt.Toolkit.getDefaultToolkit().getImage(url);
    }

}