/*
 * @(#)/SliceStack.java	1.7 96/03/31 by Andrew Barclay abb@nuccard.eushc.org
 *
 * Copyright (c) 1995 Andrew B. Barclay All Rights Reserved.
 */

// I like to know what I'm importing for sanity checks.
import java.applet.Applet ;
import java.applet.AppletContext ;
import java.awt.Color ;
import java.awt.Dimension ;
import java.awt.Event ;
import java.awt.Graphics ;
import java.awt.Image ;
import java.awt.image.ImageObserver ;
import java.awt.Rectangle ;
import java.util.Enumeration ;

import SlicerControl ;
import SlicerDisplay ;
import SlicerDisplayInfo ;
import SlicerDisplayGraphic ;

/**
 * An applet that displays stacks (one on top of another)
 * of orthogonal slices from volume images.  It receives the
 * slice data and positioning info from a Volume that is owned
 * by a SlicerControl applet on the same page.  Communication with
 * the SlicerControl is through methods of the SlicerDisplay
 * interface.  If no SlicerControl appears, the applet will wait
 * indefinitely.
 *
 * @see SlicerDisplay
 * @see SlicerControl
 * @see Volume
 *
 * @version	%I% %D%
 * @author 	Andrew Barclay
 */

public class SliceStack extends Applet implements ImageObserver, SlicerDisplay {
    // init parameters:
    String controlname ;
    int axis ;
    double thickness ;
    double zoom ;

    // state info:
    Thread me ;
    SlicerControl control ;
    SlicerDisplayInfo sdi ;
    Image curimage ;
    int imgw = -1, imgzw = -1 ;
    int imgh = -1, imgzh = -1 ;
    double xscale = 1.0 ;
    double yscale = 1.0 ;
    boolean selected = false ;
    Rectangle hashrects[] = new Rectangle[4] ;
    Color hashcolors[] = new Color[4] ;
    Color bordercolor = null ;

    // look and feel:
    static final long updateRate = 100 ;
    static final int xpad = 3 ;
    static final int ypad = 3 ;
    static final int hashheight = 8 ;
    static final int highlightwidth = 3 ;

    boolean debug = false ;

    public String getAppletInfo() {
	return "SliceStack by Andrew Barclay" ;
    }

    public String[][] getParameterInfo() {
	String[][] info = {
	    {"control",		"string",	"name of SlicerControl applet"},
	    {"axis",		"0|1|2",	"X, Y, or Z axis slicing"},
	    {"slicethickness",	"double",	"mm"},
	    {"zoom",		"double",	"zoom factor"},
	    {"bgcolor",		"int-base16",	"background color, no # or 0x"},
	} ;
	return info ;
    }

    public void init() {
	// clear all the sizes.
	imgw = imgzw = imgh = imgzh = -1 ;

	// bug: this has got to go
	String param = getParameter( "AXIS" ) ;
	axis = Integer.parseInt( param ) ;
	dbg( "init - axis="+axis ) ;

	param = getParameter( "SLICETHICKNESS" ) ;
	// bug: should check > 0.0 ?
	thickness = (param == null) ? 0.0 : parseDouble( param ) ;
	dbg( "init - thickness="+thickness ) ;

	param = getParameter( "ZOOM" ) ;
	zoom = (param == null) ? 1.0 : parseDouble( param ) ;
	dbg( "init - zoom="+zoom ) ;

	controlname = getParameter( "CONTROL" ) ;
	dbg( "init - controlname="+controlname ) ;

	// For the contest only -- the image should occupy the
	// the whole applet.
	// I'm taking the easy way out on this. (just assume hex int
	// with no leading "0x" or "#").
	param = getParameter( "BGCOLOR" ) ;
	if( param != null ) {
	    dbg( "init - color string="+param ) ;
	    Color bgcolor = new Color( Integer.parseInt( param, 16 ) ) ;
	    dbg( "init - color="+bgcolor ) ;
	    setBackground( bgcolor ) ;
	}
    }

    // why is there no parseDouble??
    private double parseDouble( String s ) {
	return (Double.valueOf(s)).doubleValue() ;
    }

    // Once the runnable is alive, start looking for a control.
    public void start() {
	// Find the named control on this page.
	getControl() ;

	// register this with the control.
	sdi = control.register( this, axis, thickness ) ;
	// bug: need to check for null sdi here, throw exception

	// initialize our state
	if( thickness == 0.0 ) {
	    thickness = sdi.vsize[2] ;
	}

	// make slice display isotropic
	double minsize =
		(sdi.vsize[0] < sdi.vsize[1]) ? sdi.vsize[0] : sdi.vsize[1] ;
	xscale = zoom * sdi.vsize[0]/minsize ;
	yscale = zoom * sdi.vsize[1]/minsize ;

	setImage( control.getSlice( this, sdi.position ) ) ;
    }

    private synchronized void getControl() {
	// sit here and wait for the control to appear.
	while( (control = (SlicerControl)getApplet(controlname)) == null ) {
	    try {
		showStatus( "SliceStack"+axis+" waiting for "+controlname+" to appear..." ) ;
		wait(1000);
	    } catch (InterruptedException ex) { }
	}
    }

    // I get a NullPointerException every time from 
    // netscape.applet.MozillaAppletContext.getApplet(String).
    // getApplets() works, so I'll roll my own
    private Applet getApplet( String name ) {
	AppletContext ac = getAppletContext() ;
	Enumeration en = ac.getApplets() ;
	while( en.hasMoreElements() ) {
	    Applet ap = (Applet)en.nextElement() ;
	    //dbg( "applet="+ap ) ;
	    if( (ap instanceof SlicerControl)
			&& name.equals(ap.getParameter("NAME")) ) {
		dbg( "getApplet: found a SlicerControl named "+name+"!" ) ;
		return ap ;
	    }
	}
	//dbg( "getApplets() done." ) ;
	return null ;
    }

    // For the SlicerDisplay interface.
    public void stopInYourTracks() {
	// I want to remove my image consumer, or stop the
	// image load thread???
	destroy() ;
    }

    // This isn't being called??
    public Dimension preferredSize() {
	dbg( "preferredSize(), zw="+imgzw+", zh="+imgzh ) ;
	if( imgzw < 0 || imgzh < 0 ) {
	    return null ;
	} else {
	    return new Dimension( imgzw+xpad*2, imgzh+ypad*2 ) ;
	}
    }

    // @return currently displayed image.
    public synchronized void setImage(Image img) {
	curimage = img ;
	// By using updateRate here, we give the display a chance to
	// catch up with rapid changes.
	repaint(updateRate) ;
	showPosition() ;
    }

    // @return true if we know image size, else false.
    private synchronized boolean checkSize() {
	if( curimage == null ) {
	    return false ;
	}

	if (imgzw < 0 || imgzh < 0 ) {
	    // This should be only place that we check/set these.
	    imgw = curimage.getWidth(this) ;
	    imgh = curimage.getHeight(this) ;
	    if (imgw < 0 || imgh < 0 ) {
		return false ;
	    } else {
		imgzw = (int)( 0.5 + xscale * imgw ) ;
		imgzh = (int)( 0.5 + yscale * imgh ) ;
		// doesn't work on anything but Solaris??
		/*
		resize( imgzw+2*xpad, imgzh+2*ypad ) ;
		layout() ;
		*/
	    }
	}
	return true ;
    }

    void paintHashmarks( Graphics gr ) {
	for( int i = 0 ; i < 4 ; i++ ) {
	    if( hashcolors[i] != null ) {
		gr.setColor( hashcolors[i] ) ;
		gr.fillRect( hashrects[i].x, hashrects[i].y,
		    hashrects[i].width, hashrects[i].height ) ;
	    }
	}
    }

    // For the SlicerDisplay interface.
    public void updateHashmarks( SlicerDisplayGraphic sdg ) {
	boolean dopaint = false ;
	bordercolor = sdg.bordercolor ;

	if (imgzw < 0 || imgzh < 0 ) {
	    return ;
	}

	if( sdg.xhashcolor != null ) {
	    int xpos = xpad + (int)(0.5+sdg.xhashpos*imgzw) ;
	    int ypos ;
	    int width = (int)(0.5+sdg.xhashwidth*imgzw) ;
	    int height = (int)(0.5+sdg.xhashlength*imgzh) ;

	    ypos = ypad ;
	    // If the shape changes, make a new rectangle...
	    if( hashrects[0] == null
			|| width != hashrects[0].width
			|| height != hashrects[0].height ) {
		hashrects[0] = new Rectangle( xpos, ypos, width, height ) ;
		dopaint = true ;
	    // otherwise, just move the old one.
	    } else if( xpos != hashrects[0].x || ypos != hashrects[0].y ) {
		hashrects[0].move( xpos, ypos ) ;
		dopaint = true ;
	    }
	    hashcolors[0] = sdg.xhashcolor ;

	    ypos = ypad + imgzh - height ;
	    // If the shape changes, make a new rectangle...
	    if( hashrects[1] == null
			|| width != hashrects[1].width
			|| height != hashrects[1].height ) {
		hashrects[1] = new Rectangle( xpos, ypos, width, height ) ;
		dopaint = true ;
	    // otherwise, just move the old one.
	    } else if( xpos != hashrects[1].x || ypos != hashrects[1].y ) {
		hashrects[1].move( xpos, ypos ) ;
		dopaint = true ;
	    }
	    hashcolors[1] = sdg.xhashcolor ;
	}

	if( sdg.yhashcolor != null ) {
	    int xpos ;
	    int ypos = ypad + (int)(0.5+sdg.yhashpos*imgzh) ;
	    int width = (int)(0.5+sdg.yhashlength*imgzw) ;
	    int height = (int)(0.5+sdg.yhashwidth*imgzh) ;

	    xpos = xpad ;
	    // If the shape changes, make a new rectangle...
	    if( hashrects[2] == null
			|| width != hashrects[2].width
			|| height != hashrects[2].height ) {
		hashrects[2] = new Rectangle( xpos, ypos, width, height ) ;
		dopaint = true ;
	    // otherwise, just move the old one.
	    } else if( xpos != hashrects[2].x || ypos != hashrects[2].y ) {
		hashrects[2].move( xpos, ypos ) ;
		dopaint = true ;
	    }
	    hashcolors[2] = sdg.yhashcolor ;

	    xpos = xpad + imgzw - width ;
	    // If the shape changes, make a new rectangle...
	    if( hashrects[3] == null
			|| width != hashrects[3].width
			|| height != hashrects[3].height ) {
		hashrects[3] = new Rectangle( xpos, ypos, width, height ) ;
		dopaint = true ;
	    // otherwise, just move the old one.
	    } else if( xpos != hashrects[3].x || ypos != hashrects[3].y ) {
		hashrects[3].move( xpos, ypos ) ;
		dopaint = true ;
	    }
	    hashcolors[3] = sdg.yhashcolor ;
	}

	if( dopaint ) {
	    /*
	     * This should not use repaint.  I need to make a method
	     * to set cliprects and do updates in there
	     * (damage/repair like IV).
	     *
	     * By using updateRate here, we give the display a chance
	     * to catch up with rapid changes.
	     */
	    repaint(updateRate) ;
	} else {
	    // Don't need a full repaint (e.g. color change).
	    paintHashmarks( getGraphics() ) ;
	    paintBorder( getGraphics() ) ;
	}
    }

    void paintBorder() {
	paintBorder( getGraphics() ) ;
    }

    void paintBorder( Graphics gr ) {
	gr.setColor( bordercolor ) ;
	for( int xy = 1 ; xy <= highlightwidth ; xy++ ) {
	    gr.drawRect( xy, xy,
		imgzw+2*xpad-2*xy,imgzh+2*ypad-2*xy ) ;
	}
    }

    public void paint( Graphics g ) {
	// Must have imgzw and imgzh set before drawing anything.
	if( checkSize() ) {
	    // Draw the current image.
	    if( xscale == 1.0 && yscale == 1.0 ) {
		g.drawImage( curimage, xpad, ypad, this ) ;
	    } else {
		g.drawImage( curimage, xpad, ypad, imgzw, imgzh, this ) ;
	    }

	    paintHashmarks( g ) ;
	    paintBorder( g ) ;
	}
    }

    public synchronized boolean imageUpdate( Image img, int infoflags,
			int x, int y, int w, int h) {
	if ( curimage == null || img != curimage ) {
	    return false ;
	}

	boolean ret = true;
	boolean dopaint = false;
	long updatetime = 0;
	if ((infoflags & WIDTH) != 0) {
	    dopaint = true ;
	    dbg( "SliceStack"+axis+": Got width = " + w ) ;
	}
	if ((infoflags & HEIGHT) != 0) {
	    dopaint = true ;
	    dbg( "SliceStack"+axis+": Got height = " + h ) ;
	}
	if ((infoflags & (FRAMEBITS | ALLBITS)) != 0) {
	    dopaint = true;
	    ret = false;
	    dbg( "SliceStack"+axis+": Finished" ) ;
	} else if ((infoflags & SOMEBITS) != 0) {
	    dopaint = true;
	    updatetime = updateRate;
	    //dbg( "Got some bits, x=" + x + " y=" + y ) ;
	    dbg( "SliceStack"+axis+": Loading..." ) ;
	}
	if ((infoflags & ERROR) != 0) {
	    perror( "SliceStack"+axis+": Image load error" ) ;
	    ret = false;
	}

	if (dopaint) {
	    repaint(updatetime);
	}
	return ret;
    }

    // Handler for slice selection.
    public boolean keyDown( Event evt, int key ) {
	//dbg( "slice display keyDown" ) ;
	if( control == null || sdi == null || !selected ) {
	    return false ;
	}

	switch( key ) {
	    case Event.UP:
	    case 'k':
	    case ' ':
		setImage( control.getSlice( this, sdi.position-sdi.vsize[2] ) ) ;
		return true ;
	    case Event.DOWN:
	    case 'j':
	    // BackSpace?
	    case 8:
		setImage( control.getSlice( this, sdi.position+sdi.vsize[2] ) ) ;
		return true ;
	    default:
		perror( "key press="+key ) ;
		return false ;
	}
    }

    public boolean mouseEnter( Event evt, int x, int y ) {
	//dbg( "slice display mouseEnter" ) ;
	requestFocus() ;
	synchronized( this ) {
	    selected = true ;
	}
	if( control == null ) {
	    return false ;
	} else {
	    control.setSelected( this ) ;
	    showPosition() ;
	    return true ;
	}
    }

    public boolean mouseExit( Event evt, int x, int y ) {
	//dbg( "slice display mouseExit" ) ;
	nextFocus() ;
	synchronized( this ) {
	    selected = false ;
	}
	return true ;
    }

    void showPosition() {
	if( sdi != null ) {
	    showStatus( "SliceStack"+sdi.axis+" at "+sdi.position+" mm" ) ;
	}
    }

    void dbg( String s ) {
	if( debug ) {
	    System.out.println( s ) ;
	    showStatus( s ) ;
	}
    }

    void perror( String s ) {
	System.err.println( s ) ;
	showStatus( s ) ;
    }
}