//Javascript called to manipulate language selection

//global variable
var langSelection;


function displayLanguage()
    {
    var langToHide, i, j, flag;

    flag=0;
    if(langSelection=='rus')
        langToHide='eng';
    else
        langToHide='rus';
    if(document.all)
        {//MSIE style JavaScript engine
        for(j=0;j<document.styleSheets.length;j++)
            for(i=0;i<document.styleSheets[j].rules.length;i++)
            {
            if(document.styleSheets[j].rules[i].selectorText.search(langSelection)!=-1)
                {document.styleSheets[j].rules[i].style.display='inline';flag++;}
            if(document.styleSheets[j].rules[i].selectorText.search(langToHide)!=-1)
                {document.styleSheets[j].rules[i].style.display='none';flag++;}
            if(flag==2) return null;
            }
        }
    if(document.getElementById)
        {
        //Mozilla style Javascript engine
	for(j=0;j<document.styleSheets.length;j++)
            for(i=0;i<document.styleSheets[j].cssRules.length;i++)
            {
            if(document.styleSheets[j].cssRules[i].selectorText.search(langSelection)!=-1)
                {document.styleSheets[j].cssRules[i].style.display='inline';flag++;}
            if(document.styleSheets[j].cssRules[i].selectorText.search(langToHide)!=-1)
                {document.styleSheets[j].cssRules[i].style.display='none';flag++;}
            if(flag==2) return null;
            }
        }
    return null;
    }

function setLanguage(lang)
    {
    langSelection=lang;
    setCookie("Glazkov_langselection",lang,'365');
    displayLanguage();
    return null;
    }

//setCookie function from Oxherder Guide
function setCookie(name, value)
    {
    var argumentList  = setCookie.arguments;
    var argumentCount = setCookie.arguments.length;
    var cookieString  = name + "=" + escape(value);
    var factor = 24 * 60 * 60 * 1000;
    var xDate = new Date();

    if (argumentCount > 2)
        {
        xDate.setTime(xDate.getTime() + factor * argumentList[2]);
        cookieString += "; expires=" + xDate;
        }
    if (argumentCount > 3)
        cookieString += ((argumentList[3] == true) ? "; secure" : "");
    document.cookie = cookieString;
    }

//getCookie function from Oxherder guide.
//returns null if cookie doesn't exists
function getCookie(name)
    {
    var searchString = name + "=";
    var searchLength = searchString.length;
    var cookieLength = document.cookie.length;
    var position     = 0;
    var endString, pointer;

    while (position < cookieLength)
        {
        pointer = position + searchLength;
        if (document.cookie.substring(position, pointer) == searchString)
            {
            endString = document.cookie.indexOf (";", pointer);
            if (endString == -1)
                endString = cookieLength;
            return unescape(document.cookie.substring(pointer, endString));
            }
        position = document.cookie.indexOf(" ", position) + 1;
        if (position == 0)
            break;
        }
    }

function checkCookie()
    {
    langSelection=getCookie("Glazkov_langselection");
    if(langSelection!="rus")
    langSelection="eng";
    }

function checkCookieInitial()
    {
    langSelection=getCookie("Glazkov_langselection");
    if(langSelection==null)
        {
        //could it be a first visit, cookie was not created?
        //create and read
        setCookie("Glazkov_langselection","eng",'365');
        langSelection=getCookie("Glazkov_langselection");
        if(langSelection==null)
           {
           //problems with cookies. Known issue for the MSIE5.0
           document.getElementById('cookies_warning').style.display="block";
           }

        }
    if(langSelection!="rus")
        langSelection="eng";
    }