package utility.borders;

import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.border.AbstractBorder;

/**
 * This border consists of dashed lines where you can specify
 * their thickness, length and colors. You can swap the specified colors
 * at any time programmatically.
 * @author Konrad Borowiecki
 */
public class DashedBorder extends AbstractBorder {
	private static final long serialVersionUID = 1L;
	private int thickness;
	private int dashSize;
	private Color color1;
	private Color color2;

	public DashedBorder(int thickness, int dashSize, Color color1, Color color2) {
		this.thickness = thickness;
		this.dashSize = dashSize;
		this.color1 = color1;
		this.color2 = color2;
	}

	@Override
	public synchronized void paintBorder(Component c, Graphics g, int x, int y, int width, int height) {
		Graphics2D g2 = (Graphics2D) g;
		//size of a step for width
		int cW = width / dashSize;
		int restCW = width % dashSize;
		for(int i = 0; i < dashSize; i++) {
			int mod1 = cW * i;
			int mod2 = cW * (i + 1);
			//if this is the last loop's operation
			if(i == dashSize - 1)
				mod2 = mod2 + restCW + 1;
			if(i % 2 == 0) {
				g2.setColor(color2);
				//top
				g2.fillRect(x + mod1, y, mod2 - mod1, thickness);
				//bottom
				g2.fillRect(x + mod1, y + height - thickness, mod2 - mod1, thickness);
			}
			if(i % 2 == 1) {
				g2.setColor(color1);
				//top
				g2.fillRect(x + mod1, y, mod2 - mod1, thickness);
				//bottom
				g2.fillRect(x + mod1, y + height - thickness, mod2 - mod1, thickness);
			}
		}
		//size of step for height
		int cH = height / dashSize;
		int restCH = height % dashSize;
		for(int i = 0; i < dashSize; i++) {
			int mod1 = cH * i;
			int mod2 = cH * (i + 1);
			//if this is the last loop's operation
			if(i == dashSize - 1)
				mod2 = mod2 + restCH + 1;
			if(i % 2 == 0) {
				g2.setColor(color1);
				//left
				//g2.drawLine(pX, pY + mod1, pX, pY + mod2);
				g2.fillRect(x, y + mod1, thickness, mod2 - mod1);
				//right
				//g2.drawLine(pX + pW, pY + mod1, pX + pW, pY + mod2);
				g2.fillRect(x + width - thickness, y + mod1, thickness, mod2 - mod1);
			}
			if(i % 2 == 1) {
				g2.setColor(color2);
				//left
				g2.fillRect(x, y + mod1, thickness, mod2 - mod1);
				//right
				g2.fillRect(x + width - thickness, y + mod1, thickness, mod2 - mod1);
			}
		}
	}

	/** A helpful function allowing to swap colors after the object was created,
	 * might be useful, for example, to create blinking effect. */
	public synchronized void swapColors() {
		Color color1Temp = color1;
		Color color2Temp = color2;
		color1 = color2Temp;
		color2 = color1Temp;
	}

	public static void main(String[] args) {
		SwingUtilities.invokeLater(new Runnable() {
			@Override
			public void run() {
				final JPanel p = new JPanel();
				p.setBackground(Color.WHITE);
				p.setPreferredSize(new Dimension(200, 200));
				final DashedBorder db = new DashedBorder(5, 20, Color.CYAN, Color.BLUE);
				p.setBorder(db);
				JPanel contentPane = new JPanel();
				contentPane.add(p);
				JButton b = new JButton("Swap Colors");
				b.addActionListener(new ActionListener() {
					@Override
					public void actionPerformed(ActionEvent e) {
						db.swapColors();
						p.repaint();
					}
				});
				contentPane.add(b);
				JFrame f = new JFrame();
				f.setContentPane(contentPane);
				f.setSize(400, 300);
				f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
				f.setVisible(true);
			}
		});
	}
}