var calhoun; 

if (typeof(calhoun) == "undefined") calhoun={};
if (typeof(calhoun.util) == "undefined") calhoun.util = {};

function setCookie(name, value, expires) {
    document.cookie = escape(name) + "=" + value + "; path=/" + 
        ((expires == null) ? "" : "; expires=" + expires.toUTCString(  ));
}

calhoun.util.checkBrowser =	function () {
		var cookies = document.cookie;  
		if(cookies.indexOf("checkedbrowser") == -1) {
			var useragent = navigator["userAgent"];
			var macOSX = useragent.indexOf("Mac OS X") != -1;
			var win7 = useragent.indexOf("Windows NT 6.1") != -1;
			var vista = useragent.indexOf("Windows NT 6.0") != -1;
			var winXP = useragent.indexOf("Windows NT 5.1") != -1;
			var win2k = useragent.indexOf("Windows NT 5.0") != -1 || useragent.indexOf("Windows 2000") != -1;
			var win98 = useragent.indexOf("Windows 98") != -1 || useragent.indexOf("Win 9") != -1;
			var safari2 = useragent.indexOf("Safari/4") != -1;
			var safari3 = useragent.indexOf("Safari/52") != -1;			
			var safari4 = useragent.indexOf("Safari/53") != -1;	
			var firefox35 = useragent.indexOf("Firefox/3.5") != -1;
			var firefox3 = useragent.indexOf("Firefox/3.0") != -1;
			var firefox2 = useragent.indexOf("Firefox/2") != -1;
			var firefox1 = useragent.indexOf("Firefox/1") != -1;
			var msie5 = useragent.indexOf("MSIE 5") != -1;
			var msie6 = useragent.indexOf("MSIE 6") != -1;
			var msie7 = useragent.indexOf("MSIE 7") != -1;
			var msie8 = useragent.indexOf("MSIE 8") != -1;
			var opera9 = useragent.indexOf("Opera/9") != -1;
			var opera10 = useragent.indexOf("Opera/10") != -1;
			var chrome3 = useragent.indexOf("Chrome/3") != -1;
			var chrome4 = useragent.indexOf("Chrome/4") != -1;
			var browserSupported = false;
			if(macOSX && (firefox35 || safari4 )) browserSupported = true; 
			else if(winXP && (msie6 || msie7 || msie8 || firefox35 || firefox3 || opera10)) browserSupported = true;
			else if(vista && (msie7 || msie8 || firefox35)) browserSupported = true;
			if(!browserSupported) {		
				var bApp="";
				var Os="unsupported OS";
				if(macOSX){ Os = "Mac OS X"; }
				if(win7){ Os = "Windows 7"; }
				if(winXP){ Os = "Windows XP"; }
				if(win2k){ Os = "Windows 2000"; }
				if(win98){ Os = "Windows 98"; }
				if(firefox1){ bApp = "Firefox 1"; }
				if(firefox2){ bApp = "Firefox 2"; }
				if(firefox3){ bApp = "Firefox 3.0"; }
				if(firefox35){ bApp = "Firefox 3.5"; }
				if(msie8){ bApp = "Internet Explorer 8"; }
				if(msie7){ bApp = "Internet Explorer 7"; }
				if(msie6){ bApp = "Internet Explorer 6"; }
				if(msie5){ bApp = "Internet Explorer 5"; }
				if(opera9){ bApp = "Opera 9"; }
				if(opera10){ bApp = "Opera 10"; }
				if(safari2){ bApp = "Safari 2"; }
				if(safari3){ bApp = "Safari 3"; }
				if(safari4){ bApp = "Safari 4"; }
				if(chrome3){ bApp = "Google Chrome 3"; }
				if(chrome4){ bApp = "Google Chrome 4"; }
				
				var msg = "The TB Genomes Database does not support\n";
				msg += "your combination of browser and operating system\n" + Os + ", " + bApp +"\n";				
				msg += "Click OK to see all supported combinations.";
				if(confirm(msg)) {
					window.open("http://developer.yahoo.com/yui/articles/gbs/", "newWindow");
				} 
			}
			var d = new Date();
			var noDate = null;
			setCookie("checkedbrowser",d.toUTCString(),noDate);
		}
	};