/**
 * Implements one of the 27 cubelets that the cube is made of.
 * 
 * @author Michael Schubart (michael@schubart.net)
 */

class Cubelet {
	// names for the faces 
	public final static int FACE_NONE=-1;  // none
	public final static int FACE_XV=0;     // orthogonal to x-axis and visible
	public final static int FACE_XH=1;     // orthogonal to x-axis and hidden 
	public final static int FACE_YV=2;     // and so on
	public final static int FACE_YH=3;
	public final static int FACE_ZV=4;
	public final static int FACE_ZH=5;

	// names for the axes
	public final static int AXIS_X=0;
	public final static int AXIS_Y=1;
	public final static int AXIS_Z=2;

	// stores the color of each of the 6 faces
	protected byte [] colors = new byte[6];

	//=========================================================================
	// Constructor, initializes each of the faces with a different color.
	//=========================================================================
	public Cubelet() {
		for (byte i = 0; i < 6; i++) {
			colors[i] = i;
		}
	}

	//=========================================================================
	// Can be used to query the color of one face.
	// return value:  the color
	//=========================================================================
	public byte getColor(int face) {
		return colors[face];
	}

	//=========================================================================
	// Rotate the cubelet. 
	// axis:        the axis around which to rotate
	// direction:   the direction in which to rotate 
	//=========================================================================
	public void rotate(int axis, int direction) {
		byte buffer;

		switch (axis) {
			case AXIS_X:
				if (direction == 1) {
					buffer = colors[FACE_YV];      
					colors[FACE_YV] = colors[FACE_ZH];
					colors[FACE_ZH] = colors[FACE_YH];
					colors[FACE_YH] = colors[FACE_ZV];
					colors[FACE_ZV] = buffer;

				} else if (direction==-1) {
					buffer = colors[FACE_YV];      
					colors[FACE_YV] = colors[FACE_ZV];
					colors[FACE_ZV] = colors[FACE_YH];
					colors[FACE_YH] = colors[FACE_ZH];
					colors[FACE_ZH] = buffer;
				}
				break;

			case AXIS_Y:
				if (direction == 1) {
					buffer = colors[FACE_XV];      
					colors[FACE_XV] = colors[FACE_ZV];
					colors[FACE_ZV] = colors[FACE_XH];
					colors[FACE_XH] = colors[FACE_ZH];
					colors[FACE_ZH] = buffer;

				} else if (direction == -1) {
					buffer = colors[FACE_XV];      
					colors[FACE_XV] = colors[FACE_ZH];
					colors[FACE_ZH] = colors[FACE_XH];
					colors[FACE_XH] = colors[FACE_ZV];
					colors[FACE_ZV] = buffer;
				}
				break;

			case AXIS_Z:
				if (direction == 1) {
					buffer = colors[FACE_XV];      
					colors[FACE_XV] = colors[FACE_YH];
					colors[FACE_YH] = colors[FACE_XH];
					colors[FACE_XH] = colors[FACE_YV];
					colors[FACE_YV] = buffer;

				} else if (direction == -1) {
					buffer = colors[FACE_XV];      
					colors[FACE_XV] = colors[FACE_YV];
					colors[FACE_YV] = colors[FACE_XH];
					colors[FACE_XH] = colors[FACE_YH];
					colors[FACE_YH] = buffer;
				}
				break;
		}
	}
}