function wHELPERS() {};

// addEvent adapated from http://ejohn.org/projects/flexible-javascript-events/
// and  Andy Smith's (http://weblogs.asp.net/asmith/archive/2003/10/06/30744.aspx)
wHELPERS.prototype.addEvent = function(obj, type, fn) {
	if(!obj) { return; }
	
	if (obj.attachEvent) {
		obj['e'+type+fn] = fn;
		obj[type+fn] = function(){obj['e'+type+fn]( window.event );}
		obj.attachEvent( 'on'+type, obj[type+fn] );
	} else if(obj.addEventListener) {			
		obj.addEventListener( type,fn, false );
	} else {
		var originalHandler = obj["on" + type]; 
		if (originalHandler) { 
		  obj["on" + type] = function(e){originalHandler(e);fn(e);}; 
		} else { 
		  obj["on" + type] = fn; 
		} 
	}
}

wHELPERS.prototype.removeEvent = function(obj, type, fn) {
	if (obj.detachEvent) {
		obj.detachEvent( 'on'+type, obj[type+fn] );
		obj[type+fn] = null;
	} else if(obj.removeEventListener)
		obj.removeEventListener( type, fn, false );
	else {
		obj["on" + type] = null;
	}
}

// Returns the event's source element 
wHELPERS.prototype.getSourceElement = function(e) {	
	if(!e) e = window.event;	
	if(e.target)
		var srcE = e.target;
	else
		var srcE = e.srcElement;
	if(!srcE) return null;
	if(srcE.nodeType == 3) srcE = srcE.parentNode; // safari weirdness		
	if(srcE.tagName.toUpperCase()=='LABEL' && e.type=='click') { 
		// when clicking a label, firefox fires the input onclick event
		// but the label remains the source of the event. In Opera and IE 
		// the source of the event is the input element. Which is the 
		// expected behavior, I suppose.		
		if(srcE.getAttribute('for')) {
			srcE = document.getElementById(srcE.getAttribute('for'));
		}
	}
	return srcE;
}

// Cancel the default execution of an event.
wHELPERS.prototype.preventEvent = function(e) {
	if (!e) e = window.event;
	if (e.preventDefault) e.preventDefault();
	else e.returnValue = false;
	return false;
}

// Cancel the propagation of the event
wHELPERS.prototype.stopPropagation = function(e) {
	if (!e) var e = window.event;
	e.cancelBubble = true;
	if (e.stopPropagation) e.stopPropagation();
}

// Generates a random ID
wHELPERS.prototype.randomId = function () {
	var seed = (new Date()).getTime();
	seed = seed.toString().substr(6);
	for (var i=0; i<6;i++)
		seed += String.fromCharCode(48 + Math.floor((Math.random()*10)));
	return "id-" + seed;
}

// Activating an Alternate Stylesheet (thx to: http://www.howtocreate.co.uk/tutorials/index.php?tut=0&part=27)
// Use this to activate a CSS Stylesheet that shouldn't be used if javascript is turned off.
// The stylesheet rel attribute should be 'alternate stylesheet'. The title attribute MUST be set.
wHELPERS.prototype.activateStylesheet = function(sheetref) {
	if(document.getElementsByTagName) {
		var ss=document.getElementsByTagName('link');
	} else if (document.styleSheets) {
		var ss = document.styleSheets;
	}
	for(var i=0;ss[i];i++ ) {
		if(ss[i].href.indexOf(sheetref) != -1) {
			ss[i].disabled = true;
			ss[i].disabled = false;			
		}
	}
}

// hasClass
wHELPERS.prototype.hasClass = function(element,className) {
	if(element && element.className) {
		if((' ' + element.className + ' ').indexOf(' ' + className +' ') != -1) {
			return true;
		}
	}
	return false;
}
wHELPERS.prototype.hasClassPrefix = function(element,className) {
	if(element && element.className) {
		if((' ' + element.className).indexOf(' ' + className) != -1) {
			return true;
		}
	}
	return false;
}



// getTop / getLeft  
// Returns pixel coordinates from the top-left window corner.
wHELPERS.prototype.getTop = function(obj) {
	var cur = 0;
	if(obj.offsetParent) {		
		while(obj.offsetParent) {
			if((new wHELPERS()).getComputedStyle(obj,'position') == 'relative' ) {
				// relatively postioned element
				return cur;
			}
			cur+=obj.offsetTop;
			obj = obj.offsetParent;
		}
	}
	return cur;
}
wHELPERS.prototype.getLeft = function(obj) {
	var cur = 0;
	if(obj.offsetParent) {		
		while(obj.offsetParent) {
			if((new wHELPERS()).getComputedStyle(obj,'position') == 'relative' ) {
				// relatively postioned element
				return cur;
			}
			cur+=obj.offsetLeft;
			obj = obj.offsetParent;
		}
	}
	return cur;
}

wHELPERS.prototype.getComputedStyle = function(element, styleName) {
	if(window.getComputedStyle) {
		return window.getComputedStyle(element,"").getPropertyValue(styleName);
	} else if(element.currentStyle) {	
		return element.currentStyle[styleName];
	}
	return false;
}
// backward compatibility
var wHelpers = wHELPERS;   


/* 
* MISC FUNCTIONS 
/* ------------------------------------------------------------------------------------------ */

// Push implementation for IE5/mac
if (!Array.prototype.push) { 
	Array.prototype.push = function() { 
		for (var i = 0; i < arguments.length; ++i) { 
			this[this.length] = arguments[i]; 
		} 
		return this.length; 
	}; 
}