package awb;
import java.awt.*;

public class Segment extends GraphicsObject
{
    // order is important!  Don't change it.
    public final static int TOP = 1;
    public final static int LEFT = 2;
    public final static int BOTTOM = 4;
    public final static int RIGHT = 8; 
    public static int SIZE = 50;

    public final static int MPP = Race.MPP;	// meters per pixel

    private RaceCar myCar;
    private int myIn, myOut;
    private boolean myBlank;
    private int myLength;

    public Segment(int x, int y)
    {
	myX = x;
	myY = y;
	myBlank = true;
	myWidth = SIZE;		// in terms of pixels,
	myHeight = SIZE;	//   not meters
    }	

    public Segment(int x, int y, int in, int out)
    {
	myX = x;
	myY = y;
	myIn = in;
	myOut = out;
	myHeight = SIZE;
	myWidth = SIZE;
	myBlank = false;
	myLength = findLength();
    }

    public static void setSize(int s)
    {
	SIZE = s;
    }

    public static int getSize()
    {
	return SIZE;
    }

    public boolean isTurn()
    {
	return (! isStraight());
    }

    public boolean isStraight()
    {
	return (((myIn + myOut) == (BOTTOM + TOP)) ||
		((myIn + myOut) == (LEFT + RIGHT)));
    }

    public boolean isLTurn()
    {
	// System.out.println("(L) Segment at " + myX + ", " + myY
		// + " has in " + myIn + " and out " + myOut);

	return (((myOut * 2) == (myIn)) ||
		((myIn == TOP) && (myOut == RIGHT)));
    }

    public boolean isRTurn()
    {
	// System.out.println("(R) Segment at " + myX + ", " + myY
		// + " has in " + myIn + " and out " + myOut);

	return (((myIn * 2) == (myOut)) ||
		((myIn == RIGHT) && (myOut == TOP)));
    }

    public int getDir(int x, int y)
    {
	if ((myIn == TOP) && (myOut == BOTTOM)) return 180;
	if ((myIn == BOTTOM) && (myOut == TOP)) return 0;
	if ((myIn == LEFT) && (myOut == RIGHT)) return 90;
	if ((myIn == RIGHT) && (myOut == LEFT)) return 270;

	double r;

	if ((myIn == RIGHT) && (myOut == BOTTOM))
	{
	    r = atan(myHeight-y,myWidth-x);
	    return (180 + toDegrees(r)) % 360;
	}

	if ((myIn == TOP) && (myOut == RIGHT))
	{
	    r = atan(y, myWidth-x);
	    return (540 - toDegrees(r)) % 360;
	}

	if ((myIn == LEFT) && (myOut == TOP))
	{
	    r = atan(y,x);
	    return toDegrees(r);
	}

	if ((myIn == BOTTOM) && (myOut == LEFT))
	{
	    r = atan(myHeight-y, x);
	    return 360 - toDegrees(r);
	}

	if ((myIn == BOTTOM) && (myOut == RIGHT))
	{
	    r = atan(myHeight-y,myWidth-x);
	    return (360 + toDegrees(r)) % 360;
	}

	if ((myIn == RIGHT) && (myOut == TOP))
	{
	    r = atan(y,myWidth-x);
	    return 360 - toDegrees(r);
	}

	if ((myIn == TOP) && (myOut == LEFT))
	{
	    r = atan(y,x);
	    return (180 + toDegrees(r)) % 360;
	}

	if ((myIn == LEFT) && (myOut == BOTTOM))
	{
	    r = atan(myHeight-y,x);
	    return (540 - toDegrees(r)) % 360;
	}

	System.out.println("ERROR!! returning -1 from getDir()");
	return -1;	// error
    }

    public void draw(Graphics g)
    {
	g.setColor(Color.green);
	g.fillRect(myX,myY,myWidth,myHeight);

	// gridlines:
	// g.setColor(Color.black);
	// g.drawRect(myX,myY,myWidth,myHeight);

	if (myBlank) return;

	g.setColor(Color.gray);
	if ((myIn + myOut) == (LEFT + RIGHT))
	{
	    g.fillRect(myX,myY+(myHeight/3),myWidth,myHeight/3);
	    return;
	}

	if ((myIn + myOut) == (TOP + BOTTOM))
	{
	    g.fillRect(myX+(myWidth/3),myY,myWidth/3,myHeight);
	    return;
	}

	if ((myIn + myOut) == (BOTTOM + RIGHT))
	{
	    int x = myX + (myWidth/3);
	    int y = myY + (myHeight/3);
	    int w = 4 * (myWidth/3);
	    g.setColor(Color.gray);
	    g.fillArc(x,y,w,w,90,90);

	    x = myX + (2 * (myWidth/3));
	    y = myY + (2 * (myHeight/3));
	    w = 2 * (myWidth/3);
	    g.setColor(Color.green);
	    g.fillArc(x,y,w,w,90,90);

	    return;
	}

	if ((myIn + myOut) == (BOTTOM + LEFT))
	{
	    int x = myX - (2 * (myWidth/3));
	    int y = myY + (myHeight/3);
	    int w = 4 * (myWidth/3);
	    g.setColor(Color.gray);
	    g.fillArc(x,y,w,w,0,90);

	    x = myX - (myWidth/3);
	    y = myY + (2 * (myHeight/3));
	    w = 2 * (myWidth/3);
	    g.setColor(Color.green);
	    g.fillArc(x,y,w,w,0,90);

	    return;
	}

	if ((myIn + myOut) == (TOP + LEFT))
	{
	    int x = myX - (2 * (myWidth/3));
	    int y = myY - (2 * (myHeight/3));
	    int w = 4 * (myWidth/3);
	    g.setColor(Color.gray);
	    g.fillArc(x,y,w,w,270,90);

	    x = myX - (myWidth/3);
	    y = myY - (myHeight/3);
	    w = 2 * (myWidth/3);
	    g.setColor(Color.green);
	    g.fillArc(x,y,w,w,270,90);

	    return;
	}

	if ((myIn + myOut) == (TOP + RIGHT))
	{
	    int x = myX + (myWidth/3);
	    int y = myY - (2 *(myHeight/3));
	    int w = 4 * (myWidth/3);
	    g.setColor(Color.gray);
	    g.fillArc(x,y,w,w,180,90);

	    x = myX + (2 * (myWidth/3));
	    y = myY - (myHeight/3);
	    w = 2 * (myWidth/3);
	    g.setColor(Color.green);
	    g.fillArc(x,y,w,w,180,90);

	    return;
	}
    }

    public boolean onTrack(int x, int y)
    {
	if ((myIn + myOut) == (TOP + BOTTOM))
	{
	    return ((x >= (myWidth/3)) && (x <= (2 * (myWidth/3))));
	}

	if ((myIn + myOut) == (LEFT + RIGHT))
	{
	    return ((y >= (myHeight/3)) && (y <= (2 * (myHeight/3))));
	}


	int inner = myWidth/3;
	int outer = 2 * (myWidth/3);

	if ((myIn + myOut) == (RIGHT + BOTTOM)) 
	{
	    x -= myWidth;
	    y -= myHeight;
	}
	if ((myIn + myOut) == (TOP + RIGHT)) 
	{
	    x -= myWidth;
	}
	if ((myIn + myOut) == (BOTTOM + LEFT))
	{
	    y -= myHeight;
	}
	// System.out.println("Segment.onTrack(): x: " + x
		// + ", y: " + y);
	int d = (int)Math.sqrt((x*x) + (y*y));

	// System.out.println("Segment.onTrack(): d2: " + d
		// + ", inner: " + inner + ", outer: " + outer);

	return ((d >= inner) && (d <= outer));	
    }

    public int getLeftDist(int x, int y)
    {
	// System.out.println("  Segment.getLeftDist()");
	// System.out.println("    x,y: " + x + ", " + y);
	// System.out.println("    w,h: " + myWidth + ", " + myHeight);
	// System.out.println("    i,o: " + myIn + ", " + myOut);

	if ((myIn == TOP) && (myOut == BOTTOM))
	    return ((2*myWidth/3) - x) * MPP;

	if ((myIn == BOTTOM) && (myOut == TOP))
	    return (x - (myWidth/3)) * MPP;

	if ((myIn == LEFT) && (myOut == RIGHT))
	    return (y - (myHeight/3)) * MPP;

	if ((myIn == RIGHT) && (myOut == LEFT))
	    return ((2*myHeight/3) - y) * MPP;

	int inner = myWidth/3;
	int outer = 2 * (myWidth/3);

	if ((myIn + myOut) == (RIGHT + BOTTOM)) 
	{
	    x -= myWidth;
	    y -= myHeight;
	}
	if ((myIn + myOut) == (TOP + RIGHT)) 
	{
	    x -= myWidth;
	}
	if ((myIn + myOut) == (BOTTOM + LEFT))
	{
	    y -= myHeight;
	}
	int d = (int)Math.sqrt((x*x) + (y*y));
	if (isLTurn()) return (d - inner) * Race.MPP;
	else return (outer - d) * Race.MPP;
    }

    public int getRightDist(int x, int y)
    {
	if ((myIn == BOTTOM) && (myOut == TOP))
	    return ((2*myWidth/3) - x) * MPP;

	if ((myIn == TOP) && (myOut == BOTTOM))
	    return (x - (myWidth/3)) * MPP;

	if ((myIn == RIGHT) && (myOut == LEFT))
	    return (y - (myHeight/3)) * MPP;

	if ((myIn == LEFT) && (myOut == RIGHT))
	    return ((2*myHeight/3) - y) * MPP;

	int inner = myWidth/3;
	int outer = 2 * (myWidth/3);

	if ((myIn + myOut) == (RIGHT + BOTTOM)) 
	{
	    x -= myWidth;
	    y -= myHeight;
	}
	if ((myIn + myOut) == (TOP + RIGHT)) 
	{
	    x -= myWidth;
	}
	if ((myIn + myOut) == (BOTTOM + LEFT))
	{
	    y -= myHeight;
	}
	int d = (int)Math.sqrt((x*x) + (y*y));
	if (isRTurn()) return (d - inner) * Race.MPP;
	else return (outer - d) * Race.MPP;
    }

    // return length in meters
    public int getLength()
    {
	return myLength;
    }

    // given position, find distance to end of segment in meters
    public int getDistanceToEnd(int x, int y)
    {
	if ((myIn == TOP) && (myOut == BOTTOM)) return MPP * (myHeight-y);
	if ((myIn == BOTTOM) && (myOut == TOP)) return MPP * y;
	if ((myIn == LEFT) && (myOut == RIGHT)) return MPP * (myWidth-x);
	if ((myIn == RIGHT) && (myOut == LEFT)) return MPP * x;

	double angle = 0;
	if ((myIn + myOut) == (RIGHT + BOTTOM))
	    angle = atan(myHeight - y, x);
	if ((myIn + myOut) == (TOP + RIGHT))
	    angle = atan(myWidth-x, y);
	if ((myIn + myOut) == (LEFT + TOP))
	    angle = atan(y,x);
	if ((myIn + myOut) == (BOTTOM + LEFT))
	    angle = atan(x,myHeight-y);

	if (isLTurn()) return (int)((myLength * angle) 
				/ (Math.PI / 2));
	else return (int)((myLength * ((Math.PI / 2) - angle)) 
				/ (Math.PI / 2));
    }

    // used as part of initialization
    private int findLength()
    {
	if (((myIn + myOut) == (TOP + BOTTOM))
		|| ((myIn + myOut) == (RIGHT + LEFT)))
	{
	    return MPP * SIZE;	
	}
	else
	{
	    return (int)(((Math.PI * SIZE) / 4) * MPP);
	}
    }

    private int toDegrees(double r)
    {
	double pipi = 2 * Math.PI;
	r = (r + pipi) % pipi;
	// System.out.println("      Segment.toDegrees(): r ==> " + r);
	return (int)((360 * r) / (pipi));
    }

    private double atan(int y, int x)
    {
	return Math.atan((double)y / (double)x);
    }
}