var ie = 0;
var agent = navigator.userAgent.toLowerCase();
var isMac = (agent.indexOf('mac') > -1) ? true : false;

if (navigator.appName.indexOf("Explorer") > -1) { 
	if (navigator.appVersion.indexOf("MSIE 5") > -1) { ie = 5 } 
	else {
		if (navigator.appVersion.indexOf("MSIE 3") > -1) { ie = 3 } 
		else { ie = parseInt(navigator.appVersion.substring(22,23)) ?parseInt(navigator.appVersion.substring(22,23)) : 0 }
	}
}

var openedPopups = new Array();

var defaults = new Array();
defaults['url'] = ""; // Default-URL: leeres fenster (was z.B. mit Javascripts fenster.document.write() gefuellt werden kann
defaults['name'] = "popup"; // Default-Name des Popups
defaults['width'] = 600; // Default-Breite
defaults['height'] = 400; // Default-Hoehe

function openPopup (url,name,w,h,switches,x,y) {

	if (!url) { url = defaults['url'] }

	if (!name) { name = defaults['name'] }

	if (!w) { w = defaults['width'] }
	else { w = parseInt(w) } // in Integer umwandeln
	if (isMac && ie && ie < 5){ w -= 20 } // auf dem Mac zu gross

	if (!h) { h = defaults['height'] }
	else { h = parseInt(h) } // in Integer umwandeln
	if (ie && ie < 5) { h -= 20} // der Explorer 4- macht das Fenster zu gross

	if (switches && switches.indexOf("f") > -1 && window.screen) { // wenn Schalter 'f' und screen-Objekt vorhanden
		w = window.screen.availWidth;
		h = window.screen.availHeight;
	}

	var xpos; // keine Defaultposition
	var ypos;
	var xInt = parseInt(x); // vermeidet Fehlermeldungen im IE3 wenn x und y nicht gesetzt
	var yInt = parseInt(y);
	if (xInt > -1 && yInt > -1) { // an best. Position x/y (Koordinaten linker oberer Fensterecke)
		xpos = xInt;
		ypos = yInt;
	}
	else {
		if (switches && window.screen) { // wenn Schalter und screen-Objekt vorhanden
			if (switches.indexOf("c") > -1) { // wenn Schalter 'c' = centered
				xpos = parseInt((window.screen.availWidth - w)/2);
				ypos = parseInt((window.screen.availHeight - h)/2);
			}
			if (switches.indexOf("f") > -1) { // wenn Schalter 'f' = fullscreen
				xpos = 0;
				ypos = 0;
			}
		}
	}

	var params = getPopupParams(w,h,switches,xpos,ypos);

	if (switches && switches.indexOf('a') > -1 && window.close){
		closePopups(); // alle offenen Popups schliessen
	}
	
	var newwin = window.open(url, name, params);

	if (switches && switches.indexOf('b') > -1 && window.moveTo && window.resizeTo && window.focus) { // wenn Schalter 'b' (borderless) sowie Methoden moveTo, resizeTo und focus vorhanden
		newwin.blur();	// Fenster verlassen
		newwin.opener.focus(); // Herkunftsfenster nach vorne bringen
		newwin.resizeTo(w,h)
		newwin.moveTo(xpos,ypos)
	}

	if (window.focus) { newwin.focus() }

	openedPopups[name] = newwin;

}

function getWindow (winname) {
	if (!winname || !openedPopups[winname] || openedPopups[winname].closed) { return false } // wenn parameter nicht vorhanden oder Array-Eintrag nicht existiert: mit falsch raus
	else { return openedPopups[winname] } // sonst: gebe Referenz auf Fenster zurueck
}

function showWindows () {
	var msg = "";
	for (var key in openedPopups ) {
		if (openedPopups[key].closed) { msg += key + ": \n" }
		else { msg += key + ": " + openedPopups[key] + "\n" }
	}
	alert(msg)
}

function closePopups () {
	if (ie && ie < 4) {return} // raus wenn IE3, sonst Fehlermeldungen
	if (window.close){ // wenn close-Methode vorhanden
		var popup, win;
		for (popup in openedPopups) {
			win = openedPopups[popup];
			if (win.close && !win.closed) { 
				win.close(); // Popup schliessen
				openedPopups[popup] = ""; // Referenz loeschen
			}
		}
	}
}

function getPopupParams (w,h,switches,xpos,ypos) {

	var width = "width=" + w;
	var height = ",height=" + h;
	var parent = ""; // z.Zt. nur NN4+
	var dirbar = "";
	var fullscreen = ""; // z.Zt. nur IE3+
	var hotkeys = ""; // z.Zt. nur NN4+
	var locbar = "";
	var menubar = "";
	var resizable = "";
	var scrollbars = "";
	var statusbar = "";
	var toolbar = "";
	if (switches) {
		if (switches.indexOf("p") > -1 ) { parent = ",dependent"	}
		if (switches.indexOf("d") > -1 ) { dirbar = ",directories"	}
		if (switches.indexOf("h") > -1 ) { hotkeys = ",hotkeys=no"	}
		if (switches.indexOf("l") > -1 ) { locbar = ",location"	}
		if (switches.indexOf("m") > -1 ) { menubar = ",menubar"	}
		if (switches.indexOf("r") > -1 ) { resizable = ",resizable"	}
		if (switches.indexOf("s") > -1 ) { scrollbars = ",scrollbars" }
		if (switches.indexOf("u") > -1 ) { statusbar = ",status"	}
		if (switches.indexOf("t") > -1 ) { toolbar = ",toolbar"	}
		if (switches.indexOf("k") > -1 || switches.indexOf("b") > -1 ) { fullscreen = ",fullscreen=1" }
	}

	var pos = "";
	var xposInt = parseInt(xpos); // vermeidet Fehlermeldungen im IE3 wenn xpos und ypos nicht gesetzt
	var yposInt = parseInt(ypos);
	if (xposInt > -1 && yposInt > -1) { pos = ",left=" + xposInt + ",top=" + yposInt }

	return width + height + parent + dirbar + hotkeys + locbar + menubar + resizable + scrollbars + statusbar + toolbar + pos + fullscreen;
}