// *****************************************************************************

var Interface = {

  textOnly: function(element) {
  var linkTags = document.getElementsByTagName('link');
  
	for (i=0;i<linkTags.length;i++){
    if(linkTags[i].rel=='stylesheet'&&linkTags[i].media=='screen') {
  	  linkTags[i].disabled = (linkTags[i].disabled?false:true);  
    }
  }
	
	if(element!=undefined){
  	if(element.innerHTML=='Click here to view a text-only version of this site.'){
  	  element.innerHTML = 'Click here to view a graphics version of this site.';
  		Cookie.write('textOnly',true);
  	} else {
  	  element.innerHTML = 'Click here to view a text-only version of this site.';
  		Cookie.write('textOnly',false);
  	}
	}
		
  },
	
	textOnlyInitialize: function(){
	  if (Cookie.read('textOnly')=='true'){
		  Interface.textOnly();
	    window.onload = function(){
			  document.getElementById('textOnlyLink').innerHTML = 'graphics';
				Interface.highLightCurrentPage();
			}
		}
	},
	
	highLightCurrentPage: function(){
    var links = document.links;
  	for (i=0;i<links.length;i++){
      if(links[i].href==location.href) {
    	  links[i].className = 'currentPage';
   	    links[i].href = '#';
      }
    }
	},
	
	treatmentsNav: function(){
    if(location.href.indexOf('.shtml')!=-1&&location.href.indexOf('/index.shtml')==-1&&location.href.indexOf('/treatments_intro.shtml')==-1){
      document.getElementById('treatments_nav').style.display='';
    }
	},
	
	toggleAnswer: function(answer) {
	  var element = document.getElementById(answer);
		if (element.style.display=='') {
			 element.style.display='none';
		}	else {
			 element.style.display='';
		}
	}

}

// *****************************************************************************

var Cookie = {

	write: function (name,value,hours) {
    if (hours) {
      var date = new Date();
      date.setTime(date.getTime()+(hours*60*60*1000));
      var expires = "; expires="+date.toGMTString();
    } else {
		expires = "";
  	}
    document.cookie = name+"="+value+expires+"; path=/";
	},

  read: function(name) {
    var nameEQ = name + "=";
    var ca = document.cookie.split(';');
    for(var i=0;i < ca.length;i++) {
      var c = ca[i];
      while (c.charAt(0)==' ') c = c.substring(1,c.length);
      if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
    }
    return null;
   }
	 	 
}

// *****************************************************************************

window.onload = Interface.highLightCurrentPage;

Interface.textOnlyInitialize();