// Setup global image container

imgData=new Array();

// Basic X-Browser utilities

function isUndefined(testVar) { var undefinedVar;return testVar===undefinedVar; }

// Array extensions

if (!Array.prototype.push) Array.prototype.push = function() {
	for (var i=0; i<arguments.length; i++) this[this.length] = arguments[i];
	return this.length;
}

Array.prototype.find = function(value, start) {
	start = start || 0;
	for (var i=start; i<this.length; i++)
		if (this[i]==value)
			return i;
	return -1;
}

Array.prototype.has = function(value) { return this.find(value)!==-1; }

// Function mapping

function map(list, function_ref) {
	var result = [];
	function_ref = function_ref || function(v) {return v};
	for (var i=0; i < list.length; i++) result.push(function_ref(list[i], i, list));
	return result;
}

function filter(list, function_ref) {
	var result = [];
	function_ref = function_ref || function(v) {return v};
	map(list, function(v) { if (function_ref(v)) result.push(v) } );
	return result;
}

// DOM

function getElement(element) {
	if (document.getElementById) {
		if (typeof element == "string") {
			element = document.getElementById(element);
			if (element===null) throw 'cannot get element: element does not exist';
		} else if (typeof element != "object") {
			throw 'cannot get element: invalid datatype';
		}
	} else throw 'cannot get element: unsupported DOM';
	return element;
}

function hasClass(element, className) {
	return getElement(element).className.split(' ').has(className);
}

function getElementsByClass(className, tagName, parentNode) {
	parentNode = !isUndefined(parentNode)? getElement(parentNode) : document;
	if (isUndefined(tagName)) tagName = '*';
	return filter(parentNode.getElementsByTagName(tagName), function(element) { return hasClass(element, className) });
}

// DOM Event handling

function addListenerToClass(event, function_ref, classID, tag, parentNode) {
	var element_list = getElementsByClass(classID, tag, parentNode);
	map(element_list, function(element) { addListenerToObject(event, element, function_ref) } );
}

function addListenerToObject(event, element, function_ref) {
	element = getElement(element);
	if (element.addEventListener) element.addEventListener(event,function_ref,false); // W3C DOM
	else if (element.attachEvent) element.attachEvent('on'+event, function(){ function_ref(new W3CDOM_Event(element)) } ); //IE DOM
	else element['on'+event] = function(){ function_ref(new W3CDOM_Event(element)) }; // Catch others
}

function W3CDOM_Event(currentTarget) {
	this.currentTarget = currentTarget;
	this.preventDefault = function() { window.event.returnValue = false; }
	return this;
}

function openWindowFromEvent(features) {
	return function(element) { openWindowFromLink(element.currentTarget, features); element.preventDefault(); }
}

function openPopupFromEvent(w, h, centered, min_w, min_h, features) {
	return function(element) { openPopupFromLink(element.currentTarget, w, h, centered, min_w, min_h, features); element.preventDefault(); }
}

// Event mouseover/down handling

function imageMouseoverFromEvent() {
	return function(element) { element.currentTarget.src = imgData[element.currentTarget.getAttribute('usemap')].src; element.preventDefault(); }
}

function imageMouseoutFromEvent() {
	return function(element) { element.currentTarget.src = element.currentTarget.defaultImage; element.preventDefault(); }
}

function preloadActiveImages() {
	var element_list = document.getElementsByTagName('img');
	for (var i=0; i < element_list.length; i++) {
		if (element_list[i].getAttribute('usemap')!==null) {
			element_list[i].defaultImage=element_list[i].src;
			addImage(element_list[i].getAttribute('usemap'));
		}
	}
}

function addImage(imagePath) {
	if (isUndefined(imgData[imagePath])) {
		imgData[imagePath]=new Image();
		imgData[imagePath].src=imagePath;
	}
}

// Standard window/popup handling

function openWindowFromLink(src, features) {
	return openWindow(src.getAttribute('href'), (src.getAttribute('target') || '_blank'), features);
}

function openPopupFromLink(src, w, h, centered, min_w, min_h, features) {
	return openPopup(src.getAttribute('href'), (src.getAttribute('target') || '_blank'), w, h, centered, min_w, min_h, features);
}

function openWindow(url, target, features) {
	if (isUndefined(features)) features = '';
	if (isUndefined(target)) target = '_blank';
	var theWindow = window.open(url, target, features);
	if (typeof theWindow.focus=="function" || typeof theWindow.focus=="object") theWindow.focus();
	//return theWindow;
}

function openPopup(url, target, w, h, centered, min_w, min_h, features) {
	if (isUndefined(min_w)) min_w = w;
	if (isUndefined(min_h)) min_h = h;
	if (isUndefined(features)) features = 'resizable=1,scrollbars=0';
	w = (screen.availWidth>=w) ? w : min_w;
	h = (screen.availHeight>=h) ? h : min_h;
	features = 'width='+w+',height='+h+','+features;
	if (centered) {
		var x=(screen.availWidth-w)/2;
		var y=((screen.availHeight-h)/2)-16;
		if (x<0) x=0;
		if (y<0) y=0;
		features += ',top='+ y +',left='+ x +',screenY='+ y +',screenX='+ x;
	}
	return openWindow(url, target, features);
}