//SpacePanel.java
import java.awt.*;

class SpacePanel extends Panel
{
	public int xstart,ystart,xwidth,yheight;
	public int ixstart,iystart,ixwidth,iyheight;
	Einstein EIN;
	FontMetrics Fm;
	Stars s;
	
	public void init()
	{
		xstart = ixstart;
		ystart = iystart;
		xwidth = ixwidth;
		yheight = iyheight;
		s = new Stars(this);
	}
	
	public void thickLine (int x0, int y0, int x1, int y1,Graphics g) 
	{
		g.drawLine(x0,y0,x1,y1);
		if (Math.abs(x1-x0) > Math.abs(y1-y0)) 
		{
			g.drawLine(x0,y0-1,x1,y1-1); 
			g.drawLine(x0,y0+1,x1,y1+1);
		}
		else 
		{
			g.drawLine(x0-1,y0,x1-1,y1); 
			g.drawLine(x0+1,y0,x1+1,y1);
		}
    }
	
	public void refocus(double newStart)
	{
		xstart = (int)newStart;
	}
	
	public void thickArrow (int x0, int y0, int x1, int y1,Graphics g) 
	{
		double w, dw = 0.5, r = 12, dx = x1-x0, dy = y0-y1;
		thickLine(x0,y0,x1,y1,g);
		//g.fillRect(x0,y0-4,x1-x0-4,7);
		w = Math.atan2(dy,dx);
		x0 = (int)(x1-r*Math.cos(w+dw)+0.5); 
		y0 = (int)(y1+r*Math.sin(w+dw)+0.5); 
		thickLine(x0,y0,x1,y1,g);
		x0 = (int)(x1-r*Math.cos(w-dw)+0.5); 
		y0 = (int)(y1+r*Math.sin(w-dw)+0.5); 
		thickLine(x0,y0,x1,y1,g);
    }

	public int mapX(double x)//Maps x to screen
	{
		Rectangle r = getBounds();
		int newX = (int) ((x-xstart)*(r.width/xwidth));		
		//console.println("X= "+x+" newX= "+newX);
		return newX;
	}
	
	public int mapBack(double newX)
	{
		Rectangle r = getBounds();
		return ((int) newX/(r.width/xwidth)+xstart);
	}
	
	public int mapY(double y)//Maps y to screen
	{
		Rectangle r = getBounds();
		int newY = (int) ((r.height/yheight)*(ystart-y));	 
		//console.println("Y= "+y+" newY= "+newY);
		return newY;
	}
	
	public SpacePanel(int xstart,int ystart,int width,int height,Einstein EIN)
	{
		super();
		this.xstart = xstart;
		this.ixstart = xstart;
		this.ystart = ystart;
		this.iystart = ystart;
		this.xwidth = width;
		this.ixwidth = width;
		this.yheight = height;
		this.iyheight = height;
		Font spaceFont = new Font("Serif",Font.PLAIN,12);
		setFont(spaceFont);
		Fm = getFontMetrics(spaceFont);
		this.EIN = EIN;
		s = new Stars(this);
	}
	
	
	public void paint(Graphics gr)
	{
		Rectangle r = getBounds();

		EIN.offscr.setColor(Color.white);
		EIN.offscr.fillRect(0,0,r.width,r.height);
		EIN.offscr.setColor(Color.black);
		EIN.offscr.fillRoundRect(0,0,r.width,r.height,20,20);
		EIN.offscr.setColor(Color.white);
		s.draw(EIN.offscr);
		for (int loop=0;loop<11;loop++)
		{
			EIN.offscr.fillOval(mapX(xstart+loop*(xwidth/10))-1,mapY(0)-1,2,2);
		}
		if ((xstart < 0) && ((xstart+xwidth) > 0))
		for (int loop=0;loop<11;loop++)
		{
			EIN.offscr.fillOval(mapX(0)-1,mapY(ystart - loop*(yheight/10))-1,2,2);
		}
		
		if (EIN.mover != null)
			EIN.mover.draw(EIN.frame,EIN.offscr);
		if (EIN.topValue != 0)
		{
			EIN.offscr.setColor(Color.blue);
			int arrowLength = EIN.topValue+5;
			thickArrow((r.width-arrowLength)/2,25,(r.width-arrowLength)/2+arrowLength,25,EIN.offscr);
		}
		gr.drawImage(EIN.image,0,0,this);
	}
	
	public void update(Graphics g)
	{
		if (EIN.frame == Reality.OBSERVER_FRAME)
		{
			if ((EIN.reality.theirX) > (xstart+xwidth))
			{
				refocus(xstart+xwidth);
			}
		}
		paint(g);
	}
		
}