//
// (C) COPYRIGHT International Business Machines Corp. 1997
// All Rights Reserved
// Licensed Materials - Property of IBM
//
// US Government Users Restricted Rights - Use, duplication or
// disclosure restricted by GSA ADP Schedule Contract with IBM Corp.
//


/*
 * $Header: /home/gda/dxcvs/dx/src/ui++/java/dx/net/Gnomon.java,v 1.1.1.1 1999/03/24 15:17:31 gda Exp $
 */

package dx.net;
import java.awt.*;
import java.net.*;
import java.io.*;

public class Gnomon extends Canvas {

    private ImageNode node;
    private Image bg;
    private float xaxis[];
    private float yaxis[];
    private float zaxis[];
    private int ixaxis[];
    private int iyaxis[];
    private int izaxis[];
    private double upvec[];
    private double frompt[];
    private double topt[];
    private final static byte[] Xbytes = (new String("X")).getBytes();
    private final static byte[] Ybytes = (new String("Y")).getBytes();
    private final static byte[] Zbytes = (new String("Z")).getBytes();
    private int x,y;
    private int iww, iwh;
    private Point start_point;
    private boolean button_down;
    private boolean just_pushed;
    private boolean xydrag;

    public void setImage (Image im) { 
	this.bg = im; 
	this.setup();
	this.setBackground(Color.black);
	repaint();
    }

    public Gnomon(ImageNode node, int ww, int wh) { 
	super(); 
	this.node = node;
	this.bg = null;
	this.xaxis = null;
	this.yaxis = null;
	this.zaxis = null;
	this.x = this.y = 0;
	this.iww = ww;
	this.iwh = wh;
	this.button_down = false;
	this.just_pushed = false;
	this.xydrag = false;
	this.ixaxis = new int[2];
	this.iyaxis = new int[2];
	this.izaxis = new int[2];
	this.start_point = new Point();
    }

    public void reshape (int x, int y, int w, int h) {
	super.reshape (x,y,w,h);
	this.x = x;
	this.y = y;
    }


    public boolean handleEvent (Event e) {
	if (e.id == Event.MOUSE_DRAG)
	    return this.mouseDrag (e, e.x, e.y);
	else
	    return super.handleEvent(e);
    }

    public void doneDrag () {
	this.button_down = false;
	this.node.setTo (this.topt, false);
	this.node.setFrom (this.frompt, false);
	this.node.setUp (this.upvec, true);
    }

    public void doDrag (int x, int y) {
	if (this.xydrag) {
	    float halfway = this.iww >> 1;
	    float percent = (x + halfway - this.start_point.x) / halfway;
	    this.drag (percent, ImageWindow.YAXIS);
	    halfway = this.iwh >> 1;
	    percent = (y + halfway - this.start_point.y) / halfway;
	    this.drag (percent, ImageWindow.XAXIS);
	    this.start_point.setLocation(x,y);
	} else {
	    float halfway = this.iwh >> 1;
	    float percent = (y + halfway - this.start_point.y) / halfway;
	    this.drag (percent, ImageWindow.ZAXIS);
	    this.start_point.setLocation(x,y);
	}
    }

    public void initDrag (Event evt, int x, int y) {
	this.just_pushed = true;
	this.button_down = true;
	this.start_point.setLocation(x,y);
	if ((evt.modifiers & Event.CTRL_MASK) == 0)
	    this.xydrag = true;
	else
	    this.xydrag = false;
    }

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

    //
    // If the mouse button is down, do XOR drawing otherwise drag the
    // gnomon in a way which ensures visibility
    //
    public void paint(Graphics g) {
	super.paint(g);
	Dimension dim = this.size();
	int x = dim.width >> 1;
	int y = dim.height >> 1;
	g.setPaintMode();
	Dimension d = this.size();
	if (this.bg != null) 
	    g.drawImage(this.bg, 0,0, d.width, d.height,
		this.x, this.y, (this.x + d.width), (this.y + d.height), 
		Color.black, this);


	if (this.xaxis != null) {
	    g.setColor(Color.black);
	    g.drawLine (x+1,y, this.ixaxis[0]+1, this.ixaxis[1]);
	    g.drawLine (x+1,y, this.iyaxis[0]+1, this.iyaxis[1]);
	    g.drawLine (x+1,y, this.izaxis[0]+1, this.izaxis[1]);

	    g.setColor(Color.white);
	    g.drawLine (x,y, this.ixaxis[0], this.ixaxis[1]);
	    g.drawLine (x,y, this.iyaxis[0], this.iyaxis[1]);
	    g.drawLine (x,y, this.izaxis[0], this.izaxis[1]);
	    this.labelAxis (g, Gnomon.Xbytes, x, y, this.ixaxis[0], this.ixaxis[1]);
	    this.labelAxis (g, Gnomon.Ybytes, x, y, this.iyaxis[0], this.iyaxis[1]);
	    this.labelAxis (g, Gnomon.Zbytes, x, y, this.izaxis[0], this.izaxis[1]);
	}
    }

    private void labelAxis (Graphics g, byte[] b, int x, int y, int x1, int y1) {
	int tx, ty;
	if ((x <= x1) && (y <= y1)) {
	    // SouthEast
	    tx = x1 + 4;
	    ty = y1 + 4;
	} else if ((x <= x1) && (y > y1)) {
	    // NorthEast
	    tx = x1 + 4;
	    ty = y1;
	} else if ((x > x1) && (y <= y1)) {
	    // SouthWest
	    ty = y1 + 4;
	    tx = x1 - 8;
	} else if ((x > x1) && (y > y1)) {
	    // NorthWest
	    tx = x1 + 4;
	    ty = y1 - 4;
	} else {
	   tx = x;
	   ty = y;
	}
	g.drawBytes (b, 0, 1, tx, ty);
    }

    private void drag(float percent, int axis) {
	double[] zero = new double[3];
	zero[0] = (double)0.0; zero[1] = (double)0.0; zero[2] = (double)0.0;
	double full_scale = ImageWindow.PI / (double)2.0;
	double theta = full_scale - (percent * full_scale);
	double xform[][] = null;

	if (axis == ImageWindow.XAXIS) {
	    double[] fromvec = new double[4];
	    fromvec[0] = this.frompt[0] - this.topt[0];
	    fromvec[1] = this.frompt[1] - this.topt[1];
	    fromvec[2] = this.frompt[2] - this.topt[2];
	    fromvec[3] = (double)0.0;
	    double[] perp = ImageWindow.cross(this.upvec, fromvec);
	    xform = ImageWindow.getTransform (perp, zero, theta);

	    //
	    // Always translate the point being transformed to 0,0,0
	    // before applying the transformation matrix.  Then translate
	    // it back after the transformation.
	    //
	    frompt[0]-= this.topt[0];
	    frompt[1]-= this.topt[1];
	    frompt[2]-= this.topt[2];
	    double from_rotated[] = ImageWindow.Rotate (frompt, xform);
	    from_rotated[0]+= this.topt[0];
	    from_rotated[1]+= this.topt[1];
	    from_rotated[2]+= this.topt[2];

	    this.frompt = from_rotated;
	    this.upvec = ImageWindow.Rotate(upvec, xform);
	} else if (axis == ImageWindow.YAXIS) {
	    xform = ImageWindow.getTransform (this.upvec, zero, theta);
	    //
	    // Always translate the point being transformed to 0,0,0
	    // before applying the transformation matrix.  Then translate
	    // it back after the transformation.
	    //
	    frompt[0]-= this.topt[0];
	    frompt[1]-= this.topt[1];
	    frompt[2]-= this.topt[2];
	    double from_rotated[] = ImageWindow.Rotate(frompt, xform);
	    from_rotated[0]+= this.topt[0];
	    from_rotated[1]+= this.topt[1];
	    from_rotated[2]+= this.topt[2];
	    this.frompt = from_rotated;
	} else if (axis == ImageWindow.ZAXIS) {
	    xform = ImageWindow.getTransform(this.frompt, this.topt, -theta);
	    this.upvec = ImageWindow.Rotate(this.upvec, xform);
	}
	this.recompute(); 
	if (this.button_down == false) 
	    repaint();
    }

    private void setup () {
	this.frompt = this.node.getFrom();
	this.topt = this.node.getTo();
	this.upvec = this.node.getUp();

	if (this.xaxis == null) {
	    this.xaxis = new float[4];
	    this.yaxis = new float[4];
	    this.zaxis = new float[4];
	}
	this.recompute();
    }

    private void recompute() {
	Dimension d = this.size();
	int ox = d.width >> 1;
	int oy = d.height >> 1;

	if (this.button_down) {
	    Graphics g = this.getGraphics();
	    if (this.just_pushed == true) {
		float[] tmp = this.xaxis;
		this.xaxis = null;
		this.paint(g);
		this.xaxis = tmp;
	    } else {
		g.setColor(Color.white);
		g.setXORMode(Color.black);
		g.drawLine (ox,oy, this.ixaxis[0], this.ixaxis[1]);
		g.drawLine (ox,oy, this.iyaxis[0], this.iyaxis[1]);
		g.drawLine (ox,oy, this.izaxis[0], this.izaxis[1]);
		this.labelAxis (g, Xbytes, ox, oy, this.ixaxis[0], this.ixaxis[1]);
		this.labelAxis (g, Ybytes, ox, oy, this.iyaxis[0], this.iyaxis[1]);
		this.labelAxis (g, Zbytes, ox, oy, this.izaxis[0], this.izaxis[1]);
	    }
	    this.just_pushed = false;
	} 

	double[] ndir = ImageWindow.normalize (this.frompt, this.topt);
	double[] horiz = ImageWindow.cross (this.upvec, ndir);

	for (int i=0; i<4; i++) 
	    this.xaxis[i] = this.yaxis[i] = this.zaxis[i] = (float)0.0;
	this.zaxis[2] = -(this.xaxis[0] = this.yaxis[1] = (float)0.8);

	float dx, dy;
	dx = ox + (ox * (float)ImageWindow.dot (this.xaxis, horiz));
	dy = oy - (ox * (float)ImageWindow.dot (this.xaxis, upvec));
	this.ixaxis[0] = (int)(this.xaxis[0] = dx);
	this.ixaxis[1] = (int)(this.xaxis[1] = dy);
	dx = ox + (ox * (float)ImageWindow.dot (this.yaxis, horiz));
	dy = oy - (ox * (float)ImageWindow.dot (this.yaxis, upvec));
	this.iyaxis[0] = (int)(this.yaxis[0] = dx);
	this.iyaxis[1] = (int)(this.yaxis[1] = dy);
	dx = ox + (ox * (float)ImageWindow.dot (this.zaxis, horiz));
	dy = oy - (ox * (float)ImageWindow.dot (this.zaxis, upvec));
	this.izaxis[0] = (int)(this.zaxis[0] = dx);
	this.izaxis[1] = (int)(this.zaxis[1] = dy);

	if (this.button_down) {
	    Graphics g = this.getGraphics();
	    g.setColor(Color.white);
	    g.setXORMode(Color.black);
	    g.drawLine (ox,oy, this.ixaxis[0], this.ixaxis[1]);
	    g.drawLine (ox,oy, this.iyaxis[0], this.iyaxis[1]);
	    g.drawLine (ox,oy, this.izaxis[0], this.izaxis[1]);
	    this.labelAxis (g, Xbytes, ox, oy, this.ixaxis[0], this.ixaxis[1]);
	    this.labelAxis (g, Ybytes, ox, oy, this.iyaxis[0], this.iyaxis[1]);
	    this.labelAxis (g, Zbytes, ox, oy, this.izaxis[0], this.izaxis[1]);
	} 
    }

}; // end Gnomon