/**
 * File: Ticker.java
 * Author: Brian Borowski
 * Date created: May 1999
 * Date last modified: August 22, 2007
 */
import java.awt.Color;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import javax.swing.JComponent;

public class Ticker extends JComponent implements Runnable {
    private int xPos, strWidth, fontHeight, fontDescent;
    private Thread runner;
    private String text;
    private Color textColor, backColor;
    private Font font = new Font("SansSerif", Font.PLAIN, 24);

    public Ticker(String text, Color textColor, Color backColor) {
        this.text = text;
        this.textColor = textColor;
        this.backColor = backColor;
        FontMetrics fontMetrics = getFontMetrics(font);
        fontHeight = fontMetrics.getHeight();
        fontDescent = fontMetrics.getDescent();
        strWidth = fontMetrics.stringWidth(text);
        xPos = Integer.MAX_VALUE;
        setDoubleBuffered(true);
    }

    public void setTextColor(Color textColor) {
        this.textColor = textColor;
    }

    public void setBackgroundColor(Color backColor) {
        this.backColor = backColor;
    }

    public void start() {
        if (runner == null) {
            runner = new Thread(this);
            runner.start();
        }
    }

    public void stop() {
        runner = null;
    }

    public void run() {
        Thread thisThread = Thread.currentThread();
        while (runner == thisThread) {
            xPos -= 1;
            repaint();
            try {
                runner.sleep(25);
            } catch (InterruptedException ie) { }
        }
    }

    public void paintComponent(Graphics g) {
        int canvasWidth = getSize().width,
            canvasHeight = getSize().height,
            yPos = (canvasHeight - fontHeight) / 2 + fontHeight - fontDescent;
        g.setColor(backColor);
        g.fillRect(0, 0, canvasWidth, canvasHeight);
        g.setColor(textColor);
        g.setFont(font);
        if (xPos > canvasWidth) {
            xPos = canvasWidth;
        }
        if (xPos < 0) {
            if (xPos <= -strWidth) {
                xPos = canvasWidth - strWidth;
            } else {
                g.drawString(text, canvasWidth + xPos, yPos);
            }
        }
        g.drawString(text, xPos, yPos);
    }
}