package cytoscape.util.swing;

import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Insets;
import java.awt.RenderingHints;

import javax.swing.AbstractAction;
import javax.swing.BorderFactory;
import javax.swing.Icon;
import javax.swing.JButton;


/**
 * Button with drop down menu.
 *
 * @version 0.7
 * @since Cytoscape 2.5
 * @author kono
  */
public class DropDownMenuButton extends JButton {
    private final Icon buttonIcon = new MenuArrowIcon();

    /**
     * Creates a new DropDownMenuButton object.
     *
     * @param action DOCUMENT ME!
     */
    public DropDownMenuButton(final AbstractAction action) {
        super(action);
        this.setFocusPainted(false);

        this.setBorder(
            BorderFactory.createEmptyBorder(4, 4, 4,
                4 + buttonIcon.getIconWidth()));
    }

    /**
     * DOCUMENT ME!
     *
     * @param g DOCUMENT ME!
     */
    public void paintComponent(Graphics g) {
        super.paintComponent(g);

        Dimension dim = getSize();
        Insets ins = getInsets();
        int x = dim.width - ins.right;
        int y = ins.top +
            ((dim.height - ins.top - ins.bottom - buttonIcon.getIconHeight()) / 2);
        buttonIcon.paintIcon(this, g, x, y);
    }

    class MenuArrowIcon
        implements Icon {
        public void paintIcon(Component c, Graphics g, int x, int y) {
            Graphics2D g2 = (Graphics2D) g;
            // Turn AA on
            g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                RenderingHints.VALUE_ANTIALIAS_ON);

            g2.setColor(Color.black);
            g2.translate(x, y);
            g2.drawLine(2, 3, 6, 3);
            g2.drawLine(3, 4, 5, 4);
            g2.drawLine(4, 5, 4, 5);
            g2.translate(-x, -y);
        }

        public int getIconWidth() {
            return 9;
        }

        public int getIconHeight() {
            return 9;
        }
    }
}