// Shared routines



function openPopup(url,windowName,features) {

	window.open(url,windowName,features);

}



function preloadImage(Url) {

	var i = new Image();

	i.src = Url;

}



function showOrHideElement(element,show) {

	element.style.display = show ? "block" : "none";

}



/* unused

function getFirstAncestorOfClass (sourceElement, className) {

	// recursively search for ancestor of sourceElement that matches className

	var elementBeingTested = sourceElement.parentNode;

	if (elementBeingTested.className == className) return elementBeingTested;

	if (!elementBeingTested.className) return null;	// if run out of elements (like at document) stop

	return getFirstAncestorOfClass(elementBeingTested, className);

}

*/



function getFirstDescendentOrSelfOfClass (sourceElement, className) {

	// recursively search for descendent of sourceElement that matches className

	// test self

	if (sourceElement.className == className) return sourceElement;

	// test children

	var child = sourceElement.firstChild;

	if (child) {

		while (child) {

			var elementBeingTested = getFirstDescendentOrSelfOfClass (child, className);

			if (elementBeingTested) return elementBeingTested;

			child = child.nextSibling;

		}

	}

	return null;

}



function getElement(frameObject,elementId) {

	if (document.getElementById) return frameObject.document.getElementById(elementId);

	if (document.all) return frameObject.document.all[elementId];

	if (document.layers) return frameObject.document.layers[elementId];

	return null;

}



function getElementsStyleObject(frameObject,elementId) {

	if (document.getElementById) return frameObject.document.getElementById(elementId).style;

	if (document.all) return frameObject.document.all[elementId].style;

	if (document.layers) return frameObject.document.layers[elementId];

	return null;

}



function getWindowHeight(frameObject) {

	if (document.all) return frameObject.document.body.clientHeight; // IE on Mac and Windows

	if (document.layers) return frameObject.document.clientHeight;

}



function getWindowWidth(frameObject) {

	if (document.all) return frameObject.document.body.clientWidth; // IE on Mac and Windows

	if (document.layers) return frameObject.document.clientWidth;

}

	

function trace (anObject) {

	alert(listObject(anObject));

}



function listObject(theObject) {

	var m = '';

	for (prop in theObject) {

		m+= prop + ":" + theObject[prop] + "\n";

		//* if theObject[prop] == 

	}

	return(m);

}



function wasLeftButton(e) {

	// takes event object (e) and decides if left button was pressed (as opposed to middle wheel button)

	var buttonPressed = /* (navigator.appName=="Netscape") ?  e.which : */ e.button;

	if (buttonPressed == 1 | buttonPressed == 0 ) return true;

	return false;

}



function appendToCookieString ( cookieString, property, value ) {

	if (cookieString!="") cookieString += "&";

	cookieString += property + ":" + escape(value);

}



function getValueFromCookieString ( cookieString, property) {

	// extract value of given property from encoding like this: "property1:value1&property2:value2"

	var pos = cookieString.indexOf(property); // at start of property label

	if (pos==-1) return null;

	pos += property.length + 1; // at start of value

	var start = pos;

	pos = cookieString.indexOf("&",pos+1);

	// if "&" not found, must be last property:value pair -- end of value is end of cookieString

	// else end of value is just before "&"

	var end = (pos==-1) ? cookieString.length : pos;

	var value = cookieString.substring(start,end);

	return unescape(value);

}

	



// SystemInfo Class

// class to handle system check (browser, etc.)

// Thanks to http://www.xs4all.nl/~ppk/js/detect.html for this code

// TODO: Rewrite?

/* 

function SystemInfo() {

	this.detect = navigator.userAgent.toLowerCase();

	this.OS = null;

	this.browser = null;

	this.version = null;

	//this.subVersion = null;

	this.total = null;

	this.thestring = null;

	this.place = null;



	if (this.checkIt('konqueror')) {

		this.browser = "Konqueror";

		this.OS = "Linux";

	}

	else if (this.checkIt('safari')) {

		this.browser = "Safari"

		//this.subVersion = this.detect.substring(8,12);

	}

	else if (this.checkIt('omniweb')) this.browser = "OmniWeb"

	else if (this.checkIt('opera')) this.browser = "Opera"

	else if (this.checkIt('webtv')) this.browser = "WebTV";

	else if (this.checkIt('icab')) this.browser = "iCab"

	else if (this.checkIt('msie')) this.browser = "Internet Explorer"

	else if (!this.checkIt('compatible')) {

		this.browser = "Netscape Navigator"

		this.version = this.detect.charAt(8);

	}

	else this.browser = "An unknown browser";



	if (!this.version) this.version = this.detect.charAt(this.place + this.thestring.length);

	

	if (!this.OS) {

		if (this.checkIt('linux')) this.OS = "Linux";

		else if (this.checkIt('x11')) this.OS = "Unix";

		else if (this.checkIt('mac')) this.OS = "Mac"

		else if (this.checkIt('win')) this.OS = "Windows"

		else this.OS = "an unknown operating system";

	}

}



SystemInfo.prototype.checkIt = function(string) {

	this.place = this.detect.indexOf(string) + 1;

	this.thestring = string;

	return this.place; // HACK: Weird

}



*/



// Saving state using cookies



/*

expires

domain



document.cookie = "version=" + escape(document.lastModified) + "; expires=" + 

// cookie values may not include semicolons, commas, or whitespace





*/