/* jseyes.js


Usage:
  1. Include this file from the head of your page
  2. Define parameters or accept the defaults
  3. Insert the image


1. Include jseyes.js from the head of your page
Insert the following line into the head of your page:
  <script src="jseyes.js"></script>


2. Define parameters
You can accept the defaults or assign new values to these variables:

jseyesimg="jseyes.gif"
  The main image. Please do not edit.

jseyeimg="jseyeblue.gif"
  The image of the eye. Must be a 21x29 solid ellipse with transparent background.


4. Insert the image
Call jseyes() where you want to see the image:
  <script>
    jseyes();
  </script>

Or call jseyes(x, y) to show the image at absolute position:
  <script>
    jseyes(100,100);
  </script>


*/




// Defaults
var jseyesimg="../stuff/jseyes.gif";
var jseyeimg="../stuff/jseyeblue.gif";
var jseyeslink="http://www.caper.com.au/pages/links.htm";


// Internal
var jseyeso=null, jseye1=null, jseye2=null;


// Browser detection

// Global variables
var browserversion=0.0;
var browsertype=0; // 0: unknown; 1:MSIE; 2:NN

// Return true if MSIE or NN detected
function browserdetect() {
  var agt= navigator.userAgent.toLowerCase();
  var appVer= navigator.appVersion.toLowerCase();
  browserversion= parseFloat(appVer);
  var iePos= appVer.indexOf('msie');
  if (iePos!=-1) browserversion= parseFloat(appVer.substring(iePos+5, appVer.indexOf(';',iePos)));
  var nav6Pos = agt.indexOf('netscape6');
  if (nav6Pos!=-1) browserversion= parseFloat(agt.substring(nav6Pos+10))
  browsertype= (iePos!=-1) ? 1 : (agt.indexOf('mozilla')!=-1) ? 2 : 0;
  return(browsertype>0);
}

browserdetect();



// General utils

// Find object by name or id
function jseyesobj(id) {
  var i, x;
  x= document[id];
  if (!x && document.all) x= document.all[id];
  for (i=0; !x && i<document.forms.length; i++) x= document.forms[i][id];
  if (!x && document.getElementById) x= document.getElementById(id);
  return(x);
}


// Move eyes
function jseyesmove(x, y) {
  var ex, ey, dx, dy;
  if (jseyeso && jseye1 && jseye2 && jseyeso.style) {
    ex=jseyeso.offsetLeft+46; ey=jseyeso.offsetTop+58;
    dx=x-ex; dy=y-ey;
    r=(dx*dx/49+dy*dy/289<1) ? 1 : Math.sqrt(49*289/(dx*dx*289+dy*dy*49));
    jseye1.style.left= r*dx+36.5; jseye1.style.top= r*dy+44;
    ex+=56; dx-=56;
    r=(dx*dx/49+dy*dy/289<1) ? 1 : Math.sqrt(49*289/(dx*dx*289+dy*dy*49));
    jseye2.style.left= r*dx+92.5; jseye2.style.top= r*dy+44;
  }
}



// Main
function jseyes() {
  var img;
  var x, y, a=false;

  if (arguments.length==2) {
    x= arguments[0];
    y= arguments[1];
    a= true;
  }

  if (browsertype>0 && browserversion>=5) {
    img= "<div id='jseyeslayer' style='position:"+
           (a ? "absolute; left:"+x+"; top:"+y : "relative")+
           "; z-index:5; width:150; height:150 overflow:hidden'>"+
	     "<div id='jseye1' style='position:absolute; left:36; top:44; z-index:6; width:21; height:29'>"+
	       "<img src='"+jseyeimg+"' width=21 height=29 onClick=\"location.href='"+jseyeslink+"'\">"+
	     "</div>"+
	     "<div id='jseye2' style='position:absolute; left:92; top:44; z-index:6; width:21; height:29'>"+
	       "<img src='"+jseyeimg+"' width=21 height=29 onClick=\"location.href='"+jseyeslink+"'\">"+
	     "</div>"+
	     "<img src='"+jseyesimg+"' width=150 height=150 onClick=\"location.href='"+jseyeslink+"'\">"+
	 "</div>";
    document.write(img);
    jseyeso=jseyesobj('jseyeslayer');
    jseye1=jseyesobj('jseye1');
    jseye2=jseyesobj('jseye2');

    switch (browsertype) {
      case 1:
        document.onmousemove=jseyesmousemoveIE;
	break;
      case 2:
        document.captureEvents(Event.MOUSEMOVE);
	document.onmousemove=jseyesmousemoveNS;
	break;
    }
  }
}


// Mouse move events
function jseyesmousemoveNS(e) {
  jseyesmove(e.pageX, e.pageY);
  //return(false);
}
function jseyesmousemoveIE() {
  jseyesmove(event.clientX+document.body.scrollLeft, event.clientY+document.body.scrollTop);
  //return(false);
}