//-------------------------------------------------------------

function preloadImages() { 
  if (document.images) {
    if (!document.preload_image_array) document.preload_image_array=new Array();
    var i;
    var number_of_images=document.preload_image_array.length;
    var args=preloadImages.arguments; 
    for(i=0; i<args.length; i++) {
      if (args[i].indexOf("#")!=0){ 
        document.preload_image_array[number_of_images]=new Image; 
        document.preload_image_array[number_of_images++].src=image_dir + args[i]; 
      } 
    }
  }
}

//-------------------------------------------------------------

function randomTopImage() {
  if (default_banner == 0) {
    this_date = new Date();
    var first_banner = Math.floor(this_date.getTime()/100000) % banner_list.length;
    document.write("<a href=\"#\" onClick=\"replaceTopImage();\"><img border=0 name=banner width=554 height=149 src=" + image_dir + "banners/" + banner_list[first_banner] + ".jpg></a>");
  } else {
    var first_banner = default_banner;
    document.write("<a href=\"#\" onClick=\"replaceTopImage();\"><img border=0 name=banner width=554 height=149 src=" + image_dir + "banners/" + first_banner + ".jpg></a>");
  }
  current_image_num = first_banner;
}

//-------------------------------------------------------------

function replaceTopImage() {
  image_num = Math.floor(Math.random() * 1.0 * banner_list.length); 
  while (image_num == current_image_num) {
    image_num = Math.floor(Math.random() * 1.0 * banner_list.length);   
  }
  document.images['banner'].src = image_dir + "banners/" + banner_list[image_num] + ".jpg";
  current_image_num = image_num;
  if (replaceTopImage.arguments.length > 0) {
    document.images['banner'].src = image_dir + replaceTopImage.arguments[0] + ".jpg";
  }
}

//-------------------------------------------------------------

function resetPage() { 
  writeDiv(story_content);		
  if (document.navbarform) {
    key = document.navbarform.current_key.value;
    if (key != "") { 
      document.images['navbar-'+key].src = image_dir +"/navbar/" +key+ "-off.gif"; 
    }
    document.images['infobar'].src = image_dir + "spacer.gif";
    setPageStateVariable('current_key','');
  }
}

//-------------------------------------------------------------

function mouseOverNavBar(key) {
  if (document.navbarform) {
    current_key = document.navbarform.current_key.value;
    if (key != current_key) { 
      document.images['infobar'].src=image_dir + "infobar/" + key +".gif";
      document.images['navbar-'+key].src = image_dir + "navbar/"+key+"-over.gif";
    }
  }
}

//-------------------------------------------------------------

function mouseOutNavBar(key) {
    if (document.navbarform) {
    	di = document.images;
    	di['navbar-'+key].src = image_dir + "navbar/"+key+"-off.gif";
    	current_key = document.navbarform.current_key.value;
    	if (current_key == '' || current_key==null || current_key =='null') { 
		di['infobar'].src=image_dir +"spacer.gif";
    	} else {
		di['navbar-'+current_key].src=image_dir +"navbar/"+current_key+"-on.gif";
		di['infobar'].src=image_dir +"infobar/" + current_key + ".gif";
    	}
    }
}

//-------------------------------------------------------------

function clickOnNavBar(key,edit_section_id) {
   document.images['navbar-'+key].src = image_dir + "navbar/"+key+"-on.gif";
   writeSectionContent(edit_section_id);
   
   current_key = document.navbarform.current_key.value;
   setPageStateVariable('current_key',key);

   if ((current_key != '') && (current_key != 'null') && (current_key != key)) { 
	document.images['navbar-'+current_key].src= image_dir +"navbar/"+current_key+"-off.gif";
   }

}


//-------------------------------------------------------------

function clickOnSearch(key) {
    ds = document.searchform;
    dss = ds.searchsite;
    di = document.images;
    di['search-'+dss.value+'-line'].src=image_dir +"search/vertical-bar.gif";
    di['search-'+dss.value].src=image_dir+"search/"+dss.value+"-off.gif";
    dss.value = key;
    di['search-'+key+'-line'].src=image_dir+"search/dimple.gif";
    di['search-'+key].src=image_dir +"search/"+key+"-on.gif";
    submitSearch();
}

//-------------------------------------------------------------

function submitSearch() {
    document.searchform.submit();
}
//-------------------------------------------------------------

function mouseOverSearch(key) {
      dss = document.searchform.searchsite;
      di = document.images;
      if (dss.value != key) {
  	di['search-'+dss.value+'-line'].src=image_dir +"search/vertical-bar.gif";
	di['search-'+key+'-line'].src=image_dir+"search/dimple.gif";
        di['search-'+key].src=image_dir+"search/"+key+"-over.gif";
      }
}

//-------------------------------------------------------------

function mouseOutSearch(key) {
    dss = document.searchform.searchsite;
    di = document.images;
    if (dss.value != key) {
	di['search-'+dss.value+'-line'].src=image_dir+"search/dimple.gif";
	di['search-'+key+'-line'].src=image_dir+"search/vertical-bar.gif";
	di['search-'+key].src=image_dir+"search/"+key+"-off.gif";
    }
}

//-------------------------------------------------------------

function mouseGo(action) {
    document.images['search-go'].src=image_dir+"search/go-"+action+".gif";
}

//-------------------------------------------------------------

function resetSearch() {
    dss = document.searchform.searchsite;
    di = document.images;
    search_list=["caltech", "directory", "calendar", "archives", "library"]
    for (i=0; i<search_list.length; i++) {
	di['search-'+search_list[i]+'-line'].src=image_dir+"search/vertical-bar.gif";
	di['search-'+search_list[i]].src=image_dir+"search/"+search_list[i]+"-off.gif";
    }
    di['search-'+dss.value+'-line'].src=image_dir+"search/dimple.gif";    
    di['search-'+dss.value].src=image_dir+"search/"+dss.value+"-on.gif";
}

function clickOnSearch(key) {
    ds = document.searchform;
    dss = ds.searchsite;
    di = document.images;
    di['search-'+dss.value+'-line'].src=image_dir +"search/vertical-bar.gif";
    di['search-'+dss.value].src=image_dir+"search/"+dss.value+"-off.gif";
    dss.value = key;
    di['search-'+key+'-line'].src=image_dir+"search/dimple.gif";
    di['search-'+key].src=image_dir +"search/"+key+"-on.gif";
    submitSearch();
}

//-------------------------------------------------------------

function MM_swapImgRestore() { //v3.0
    var i,x,a=document.MM_sr; for(i=0;a&&i<a.length&&(x=a[i])&&x.oSrc;i++) x.src=x.oSrc;
}

//-------------------------------------------------------------

function MM_findObj(n, d) { //v4.01
    var p,i,x;  if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
	d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
    if(!(x=d[n])&&d.all) x=d.all[n]; for (i=0;!x&&i<d.forms.length;i++) x=d.forms[i][n];
    for(i=0;!x&&d.layers&&i<d.layers.length;i++) x=MM_findObj(n,d.layers[i].document);
    if(!x && d.getElementById) x=d.getElementById(n); return x;
}

//-------------------------------------------------------------

function MM_swapImage() { //v3.0
    var i,j=0,x,a=MM_swapImage.arguments; document.MM_sr=new Array; for(i=0;i<(a.length-2);i+=3)
									if ((x=MM_findObj(a[i]))!=null){document.MM_sr[j++]=x; if(!x.oSrc) x.oSrc=x.src; x.src=a[i+2];}
}