/*
 * Performance-Hinweis für Mac mit Mac OS X < 10.4 und/oder Safari < 3
 * kein jQuery wegen Safari 1 und 2 Kompatibilität!
 *
 */

window.onload = function(){
	var agent = navigator.userAgent;
	var browser = navigator.appVersion;
	var platform = navigator.platform;
	var safariBuildNr = browser.substring(browser.lastIndexOf("/")+1,browser.length);
	
	/*alert("Platform: \n" + navigator.platform + 
			  "\nuserAgent: " + navigator.userAgent + 
			  "\nappCodeName: " + navigator.appCodeName + 
			  "\nappName: " + navigator.appName + 
			  "\nappVersion: " + navigator.appVersion);*/
	
	// Überprüfen, ob Mac mit mindestens OS X 10.4 oder mindestens Safari 3
	if(platform.indexOf("Mac") != -1){
		if(agent.indexOf("X 10") == -1){
			showOverlay();
		} else if(browser.indexOf("Safari") != -1 && safariBuildNr < 412){
			showOverlay();
		}
	}
}

function showOverlay(){
	if(document.cookie.indexOf("performance=ok") == -1){
		document.getElementById('overlay').style.visibility = 'visible';
	}
}

function hideOverlay(){
	document.getElementById('overlay').style.visibility = 'hidden';
	document.cookie = "performance=ok";
}