var layerRef="null", styleSwitch="null", vis="null", invis="null";
var isShown=0;
var MLayers=new Array();
var isDOM;
var isNN4;
var isMSIE;
var isOpera;
var isOpera5;
var isMSIE5;
var isMozilla;
var Loaded=false

function get_is(){
isDOM=document.getElementById //DOM1 browser (MSIE 5+, Netscape 6, Opera 5+)
isMSIE=document.all && document.all.item //Microsoft Internet Explorer 4+
isNN4=document.layers //Netscape 4.*
isOpera=window.opera //Opera
isOpera5=isOpera && isDOM //Opera 5+
isMSIE5=isDOM && isMSIE //MSIE 5+
isMozilla=isNetscape6=isDOM && !isMSIE && !isOpera //Mozilla или Netscape 6.*
//if(isDOM){alert("DOM")}
//else if(isMSIE){alert("MSIE")}
//else if(isNN4){alert("NN4")}
//else if(isMozilla){alert("Mozilla")}
//else if(isMSIE5){alert("MSIE5")}
//else if(isOpera){alert("Opera")}
//else if(isOpera5){alert("Opera")}
//else{ alert("false")}
}

function initLay(){
Loaded=true
  get_is();
  if(isNN4){
    vis="show"; invis="hide";
    layerRef="document.layers";
    styleSwitch="";  
    lc='['; rc=']';
  }
  else if(isMSIE){
    vis="visible"; invis="hidden";
    layerRef="document.all";
    styleSwitch=".style";
    lc='['; rc=']';
  }
  else if(isDOM || isMozilla || isMSIE5){
    vis="visible"; invis="hidden";
    layerRef="document.getElementById";
    styleSwitch=".style"; 
    lc='('; rc=')';
  }
  else{return false;}
  

MLayers[0]="about";
MLayers[1]="methods";
MLayers[2]="applic";
MLayers[3]="news";

}
 
function showLayer(layerName){
if(!Loaded){return}
var str=layerRef+lc+'"'+layerName+'"'+rc+styleSwitch+'.visibility=vis';
//alert(str);
eval(str);
}
        
function hideLayer(layerName){
//Protecting from IE (suxx!)
  if((isMSIE || isMSIE5) && !(window.event.toElement && window.event.toElement.className != "menu")){return;}
  str=layerRef+lc+'"'+layerName+'"'+rc+styleSwitch+'.visibility=invis';
  //alert(str)
  eval(str);
}

function switchLay(layerName){
var state=eval(layerRef+lc+'"'+layerName+'"'+rc+styleSwitch+'.visibility');
  if(state == vis){hideLayer(layerName)} 
  else{
     for(i=0;i<MLayers.length;i++){
	if(layerName == MLayers[i]){showLayer(layerName)}
	else{hideLayer(MLayers[i])}
     }	
  }
}

function hideAllLay(){
//alert(myEvent.srcElement)
for(i=0;i<MLayers.length;i++){hideLayer(MLayers[i])}
}


//===========================================================================
//				Функции регистрации
//===========================================================================

var Tech0=new Image();
Tech0.src="../_media/tech0.gif";
var Tech1=new Image();
Tech1.src="../_media/tech.gif";

function outImg(){
if(checkReg()){document.tech.src=Tech1.src; return 1;}
document.tech.src=Tech0.src;
return 0;
}

//проверка записи о регистрации в cookie
function checkReg(){
var CookieArray=new Array();
CookieArray=document.cookie.split("; ");
var Pair
for(i=0;i<CookieArray.length;i++){
  Pair=CookieArray[i].split("=");
  if(Pair[0]=="enviro" && Pair[1].length==6){return 1;} //REGISTRATION PASSED! ACCESS GRANTED!
}
return 0; //ACCESS DENIED!
}

//переключение на страницу доп. информации
function switchPage(pURL){
//alert(checkReg());
if(checkReg()){
 var DocPath=pURL.split("/"); //parse URL
 var nameOfFile=DocPath[DocPath.length-1]; //what the filename? 
 var name1=nameOfFile.split(".");
 var nameExt=name1[0]+"_ext.htm"; //set name of ext-file
 self.location=nameExt;
}
else{openReg("../reg.htm")}
}

function openReg(path){
RegObj=window.open(path,"Reg","top=0,left=0,width=550,height=500,status=no,toolbar=no,menubar=no,scrollbars=yes")
}