import java.awt.*;

public class SketchBoard extends Canvas
{
	public Line lines[]=null;
	public float scanx;
	public InterestingPoint currentIP=null;
	private int lastx=0;
	public int MAX_X, MAX_Y, OFF_X, OFF_Y, NUM_LINES;
	public Line select_line=null;

	private InterestingPoint lastpoint=null;

	public SketchBoard(Line l[], float Scanx, InterestingPoint ip, 
					   Line sl, int _MAX_X, int _MAX_Y, int _OFF_X, int _OFF_Y, int _NUM_LINES)
	{
		lines=l;
		scanx=Scanx;
		currentIP=ip;
		select_line=sl;
		MAX_X=_MAX_X;
		MAX_Y=_MAX_Y;
		OFF_X=_OFF_X;
		OFF_Y=_OFF_Y;
		NUM_LINES=_NUM_LINES;
	}


	public void paint(Graphics gd)
	{
		if(lines==null) return;

		// erase our previous stuff
		if(lastpoint!=null) lastpoint.erase(gd, OFF_X, 0+ OFF_Y, this.getBackground());
		gd.setColor(this.getBackground());
		Dimension d=this.size();
		gd.fillRect(0,0,d.width, d.height);

		gd.drawLine(lastx +OFF_X,0+ OFF_Y,
					lastx +OFF_X, MAX_Y+ OFF_Y);
		// draw our new stuff
		gd.setColor(Color.black);
		for(int i=0;i<NUM_LINES;i++)
		{
			gd.drawLine((int)lines[i].p1.x+ OFF_X, (int)lines[i].p1.y + OFF_Y,
					   (int)lines[i].p2.x+ OFF_X, (int)lines[i].p2.y + OFF_Y);
		}
		gd.setPaintMode();
		lastx=(int)scanx;
		gd.setColor(Color.red);
		gd.drawLine((int)scanx +OFF_X,0+ OFF_Y, 
					(int)scanx +OFF_X, MAX_Y+OFF_Y);

		if(select_line!=null)
	    {
			gd.setColor(Color.blue);
			gd.drawLine((int)select_line.p1.x+OFF_X,(int)select_line.p1.y+OFF_Y,
						(int)select_line.p2.x+OFF_X,(int)select_line.p2.y+OFF_Y);
		}
		if(currentIP!=null) currentIP.paint(gd, OFF_X, 0+ OFF_Y);
		lastpoint=currentIP;
	} // paint

	public void update(Graphics g)
	{
		paint(g);
	}

	public void repaint(Graphics g)
	{
		paint(g);
	}

}