/** Jonathon Diamond developed the basic solution to
    tiling Eaine's kitchen. With 2 or three revisions by
    Gries and Diamond, the following version was created.
 */ 
import java.awt.*;

/** An instance contains methods to tile Elaine's kitchen. */
public class KitchenTurtle extends Turtle {
    /** We explain how a 2^n by 2^n kitchen is mapped onto
     the graphics panel.<br>
     
     1. The upper left corner of the kitchen is at
     pixel (100, 100) of the graphics panel.<br />
     2. Each square of the kitchen occupies a 10x10 square
     of pixels in the graphics panel. This means that
     square (i, j) of the kitchen has (100 + i*10, 100 + j*10)
     as its top-left pixel on the panel.
     
     All specifications are written in terms of the 2^n x 2^n
     kitchen, and the method bodies have to translate coordinates
     of kitchen squares into coordinates of pixels on the panel.
     */
    private int number;
    
    /** = b ^ c, i.e. b multiplied by itself c times.
        Precondition: c >= 0. */
    public static int exp(int b, int c) {
        if (c == 0) {
            return 1;
        }
        
        if (c%2 == 0) {// Note: for even c, b^c = (b*b)^(c/2)
            return exp(b*b, c/2);
        }
        
        return b * exp(b, c-1); // Note: b^c = b * b^(c-1)
    }
    
    /** Draw a 2^n by 2^n kitchen, put a refrigerator (or other object)
        on square (x, y) -- square does not have to be tiled-- and tile
        the kitchen. If x or y is not in the range 0..2^n-1, use 0 for it.
        Pause msecs after putting each tile down.
        Precondition: n >= 0.
     */
    public void tileKitchen(int x, int y, int n, int msec) {
        int p2n= exp(2, n);  // 2 to the power n.
        if (x < 0 || x >= p2n)
            x= 0;
        if (y < 0 || y >= p2n)
            y= 0;
        Point in= new Point(x, y); // This is where the fridge is
        
        setPanelSize();
        clear();
        
        // Draw a square around the kitchen.
        setColor(Color.black);
        Rectangle rec= new Rectangle(0, 0, p2n, p2n);
        
        // Remember: for drawRectangle, place the turtle at its center. 
        // moveTo(100 + 5 * p2n, 100 + 5 * p2n, 0);
        // drawRectangle(10 * p2n, 10 * p2n);
        moveTo(100 + 5 * p2n - 1, 100 + 5 * p2n - 1, 0);
        drawRectangle(10 * p2n + 1, 10 * p2n + 1);
        
        // Place a red refrigerator (or other object) at (x, y). 
        moveTo(105 + x * 10, y * 10 + 105, 0);
        Color orig= getColor();
        setColor(Color.red);
        fillRectangle(10, 10);
        
        setColor(orig);
        
        // Place the tiles
        number= 0;
        putTiles(rec, in, msec);
        
    }
    
    /** Draw a 2^n by 2^n kitchen, but a refrigerator (or other object)
        on square (x, y) -- square does not have to be tiled-- and tile
        the kitchen. If x or y is not in the range 0..2^n-1, use 0 for it.
        Pause 100 after putting each tile down.
        Precondition: n >= 0.
     */
    public void tileKitchen(int x, int y, int n) {
        tileKitchen(x, y, n, 100);
    }
   
    /** Tile the square kitchen given by rec. Its side length is
        a power of 2. The position of the refrigerator (or other
        object) is given by Point in. Pause msec microseconds
        after placing each tile.
     */
    public void putTiles(Rectangle rec, Point in, int msec) {
        //base case
        if (rec.getWidth() == 1) {
            return;
        }
        
         
        // (mx, my) is the position of upper lefthand corner of
        // lower right quadrant.
        int side= (int) rec.getWidth() / 2;// half the width (or height)
        int mx= rec.x + side;
        int my= rec.y + side;
        
        // fridgei will contain the position of fridge in quadrant i
        // 1 = upper left, 2 = upper right,
        // 3 = lower left, 4 = upper right quadrant.
        Point fridge1= new Point(mx-1, my-1);
        Point fridge2= new Point(mx, my-1);
        Point fridge3= new Point(mx-1, my);
        Point fridge4= new Point(mx, my);
       
        // Lay one tile in the three quadrants that do not contain
        // an already filled tile and set fridgei for the other 
        // quadrant to in (the real refrigerator).
        setColor(randColor());
        //setColor(tColor(number % 13 + 1));
        
        // Fix upper left quadrant
        if (in.x < mx && in.y < my) {
            fridge1= in;
        } else{
            moveTo(105 + (mx-1) * 10, 105 + (my-1) * 10, 0);
            fillRectangle(10, 10); // lay 1/3 of a tile
        }
        
        // Fix upper right quadrant
        if (in.x >= mx && in.y < my) {
            fridge2= in;
        } else{
            moveTo(105 + mx * 10, 105 + (my-1) * 10, 0);
            fillRectangle(10, 10); // lay 1/3 of a tile
        }
       
        // Fix lower left quadrant
        if (in.x < mx && in.y >= my) {
            fridge3= in;
        } else{
            moveTo(105 + (mx-1) * 10, 105 + my * 10, 0);
            fillRectangle(10, 10); // lay 1/3 of a tile
        }
        
        // Fix lower right quadrant
        if (in.x >= mx && in.y >= my) {
            fridge4= in;
        } else{
            moveTo(105 + mx * 10, 105 + my * 10, 0);
            fillRectangle(10, 10); // lay 1/3 of a tile
        }
        number= number + 1;
        
        // Pause for msec microseconds
        pause(msec);
        
        // Place tiles in the four quadrants
        putTiles(new Rectangle(rec.x, rec.y, side, side), fridge1, msec);
        putTiles(new Rectangle(mx, rec.y, side, side), fridge2, msec);
        putTiles(new Rectangle(rec.x, my, side, side), fridge3, msec);
        putTiles(new Rectangle(mx, my, side, side), fridge4, msec);
    }    
}