var sUserAgent = navigator.userAgent;
var fAppVersion = parseFloat(navigator.appVersion);
 
function compareVersions(sVersion1, sVersion2) 
{
 
    var aVersion1 = sVersion1.split(".");
    var aVersion2 = sVersion2.split(".");
 
    if (aVersion1.length > aVersion2.length) 
    {
        for (var i=0; i < aVersion1.length - aVersion2.length; i++) 
        {
            aVersion2.push("0");
        }
    } 
    else if (aVersion1.length < aVersion2.length) 
    {
        for (var i=0; i < aVersion2.length - aVersion1.length; i++) 
        {
            aVersion1.push("0");
        }    
    }
 
    for (var i=0; i < aVersion1.length; i++) 
    {
 
        if (aVersion1[i] < aVersion2[i]) 
        {
            return -1;
        } 
        else if (aVersion1[i] > aVersion2[i]) 
        {
            return 1;
        }    
    }
 
    return 0;
 
}
 
var isOpera = sUserAgent.indexOf("Opera") > -1;
var isMinOpera4 = isMinOpera5 = isMinOpera6 = isMinOpera7 = isMinOpera7_5 = false;
 
if (isOpera) 
{
    var fOperaVersion;
    if(navigator.appName == "Opera") 
    {
        fOperaVersion = fAppVersion;
    } 
    else 
    {
        var reOperaVersion = new RegExp("Opera (\\d+\\.\\d+)");
        reOperaVersion.test(sUserAgent);
        fOperaVersion = parseFloat(RegExp["$1"]);
    }
 
    isMinOpera4 = fOperaVersion >= 4;
    isMinOpera5 = fOperaVersion >= 5;
    isMinOpera6 = fOperaVersion >= 6;
    isMinOpera7 = fOperaVersion >= 7;
    isMinOpera7_5 = fOperaVersion >= 7.5;
}
 
var isKHTML = sUserAgent.indexOf("KHTML") > -1 
              || sUserAgent.indexOf("Konqueror") > -1 
              || sUserAgent.indexOf("AppleWebKit") > -1; 
 
var isMinSafari1 = isMinSafari1_2 = false;
var isMinKonq2_2 = isMinKonq3 = isMinKonq3_1 = isMinKonq3_2 = false;
 
if (isKHTML) 
{
    isSafari = sUserAgent.indexOf("AppleWebKit") > -1;
    isKonq = sUserAgent.indexOf("Konqueror") > -1;
 
    if (isSafari) 
    {
        var reAppleWebKit = new RegExp("AppleWebKit\\/(\\d+(?:\\.\\d*)?)");
        reAppleWebKit.test(sUserAgent);
        var fAppleWebKitVersion = parseFloat(RegExp["$1"]);
 
        isMinSafari1 = fAppleWebKitVersion >= 85;
        isMinSafari1_2 = fAppleWebKitVersion >= 124;
    } 
    else if (isKonq) 
    {
 
        var reKonq = new RegExp("Konqueror\\/(\\d+(?:\\.\\d+(?:\\.\\d)?)?)");
        reKonq.test(sUserAgent);
        isMinKonq2_2 = compareVersions(RegExp["$1"], "2.2") >= 0;
        isMinKonq3 = compareVersions(RegExp["$1"], "3.0") >= 0;
        isMinKonq3_1 = compareVersions(RegExp["$1"], "3.1") >= 0;
        isMinKonq3_2 = compareVersions(RegExp["$1"], "3.2") >= 0;
    } 
 
}
 
var isIE = sUserAgent.indexOf("compatible") > -1 
           && sUserAgent.indexOf("MSIE") > -1
           && !isOpera;
 
var isMinIE4 = isMinIE5 = isMinIE5_5 = isMinIE6 = false;
 
if (isIE) 
{
    var reIE = new RegExp("MSIE (\\d+\\.\\d+);");
    reIE.test(sUserAgent);
    var fIEVersion = parseFloat(RegExp["$1"]);
 
    isMinIE4 = fIEVersion >= 4;
    isMinIE5 = fIEVersion >= 5;
    isMinIE5_5 = fIEVersion >= 5.5;
    isMinIE6 = fIEVersion >= 6.0;
}
 
var isMoz = sUserAgent.indexOf("Gecko") > -1
            && !isKHTML;
 
var isMinMoz1 = sMinMoz1_4 = isMinMoz1_5 = false;
 
if (isMoz) 
{
    var reMoz = new RegExp("rv:(\\d+\\.\\d+(?:\\.\\d+)?)");
    reMoz.test(sUserAgent);
    isMinMoz1 = compareVersions(RegExp["$1"], "1.0") >= 0;
    isMinMoz1_4 = compareVersions(RegExp["$1"], "1.4") >= 0;
    isMinMoz1_5 = compareVersions(RegExp["$1"], "1.5") >= 0;
}
 
var isNS4 = !isIE && !isOpera && !isMoz && !isKHTML 
            && (sUserAgent.indexOf("Mozilla") == 0) 
            && (navigator.appName == "Netscape") 
            && (fAppVersion >= 4.0 && fAppVersion < 5.0);
 
var isMinNS4 = isMinNS4_5 = isMinNS4_7 = isMinNS4_8 = false;
 
if (isNS4) 
{
    isMinNS4 = true;
    isMinNS4_5 = fAppVersion >= 4.5;
    isMinNS4_7 = fAppVersion >= 4.7;
    isMinNS4_8 = fAppVersion >= 4.8;
}
 
var isWin = (navigator.platform == "Win32") || (navigator.platform == "Windows");
var isMac = (navigator.platform == "Mac68K") || (navigator.platform == "MacPPC") 
            || (navigator.platform == "Macintosh");
 
var isUnix = (navigator.platform == "X11") && !isWin && !isMac;
 
var isWin95 = isWin98 = isWinNT4 = isWin2K = isWinME = isWinXP = false;
var isMac68K = isMacPPC = false;
var isSunOS = isMinSunOS4 = isMinSunOS5 = isMinSunOS5_5 = false;
 
if (isWin) 
{
    isWin95 = sUserAgent.indexOf("Win95") > -1 
              || sUserAgent.indexOf("Windows 95") > -1;
    isWin98 = sUserAgent.indexOf("Win98") > -1 
              || sUserAgent.indexOf("Windows 98") > -1;
    isWinME = sUserAgent.indexOf("Win 9x 4.90") > -1 
              || sUserAgent.indexOf("Windows ME") > -1;
    isWin2K = sUserAgent.indexOf("Windows NT 5.0") > -1 
              || sUserAgent.indexOf("Windows 2000") > -1;
    isWinXP = sUserAgent.indexOf("Windows NT 5.1") > -1 
              || sUserAgent.indexOf("Windows XP") > -1;
    isWinNT4 = sUserAgent.indexOf("WinNT") > -1 
              || sUserAgent.indexOf("Windows NT") > -1 
              || sUserAgent.indexOf("WinNT4.0") > -1 
              || sUserAgent.indexOf("Windows NT 4.0") > -1 
              && (!isWinME && !isWin2K && !isWinXP);
} 
 
if (isMac) 
{
    isMac68K = sUserAgent.indexOf("Mac_68000") > -1 
               || sUserAgent.indexOf("68K") > -1;
    isMacPPC = sUserAgent.indexOf("Mac_PowerPC") > -1 
               || sUserAgent.indexOf("PPC") > -1;  
}
 
if (isUnix) 
{
    isSunOS = sUserAgent.indexOf("SunOS") > -1;
 
    if (isSunOS) 
    {
        var reSunOS = new RegExp("SunOS (\\d+\\.\\d+(?:\\.\\d+)?)");
        reSunOS.test(sUserAgent);
        isMinSunOS4 = compareVersions(RegExp["$1"], "4.0") >= 0;
        isMinSunOS5 = compareVersions(RegExp["$1"], "5.0") >= 0;
        isMinSunOS5_5 = compareVersions(RegExp["$1"], "5.5") >= 0;
    }
}