var Tips = {
		tips: [],
		zIndex: 1200,

		add: function(tip) {
	this.tips.push(tip);
},

remove: function(element) {
	var tip = this.tips.find(function(t){ return t.element == $(element); });
	if (!tip) return;

	this.tips = this.tips.reject(function(t) { return t==tip; });
	tip.deactivate();
	if(tip.tooltip) tip.wrapper.remove();
	if(tip.underlay) tip.underlay.remove();
}
}

var Tip = Class.create();
Tip.prototype = {

		initialize: function(element, content) {
	this.element = $(element);
	Tips.remove(this.element);

	this.content = content;

	this.options = Object.extend({
		className: 'tooltip',
		duration: 0.3, // duration of the effect
		effect: false, // false, 'appear' or 'blind'
		hook: false, // { element: {'topLeft|topRight|bottomLeft|bottomRight'}, tip: {'topLeft|topRight|bottomLeft|bottomRight'}
		offset: (arguments[2] && arguments[2].hook) ? {x:0, y:0} : {x:16, y:16},
				fixed: false, // follow the mouse if false
				target: this.element, // or another element
				title: false,
				viewport: true // keep within viewport if mouse is followed
	}, arguments[2] || {});

	this.target = $(this.options.target);

	if (this.options.hook) {
		this.options.fixed = true;
		this.options.viewport = false;
	}

	if (this.options.effect) {
		this.queue = { position: 'end', limit: 1, scope: ''}
		var c = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXTZabcdefghiklmnopqrstuvwxyz";
		for (var i=0; i<6; i++) {
			var r = Math.floor(Math.random() * c.length);
			this.queue.scope += c.substring(r,r+1);
		}
	}

	this.buildWrapper();

	Tips.add(this);
	this.activate();
},

activate: function() {
	this.eventShow = this.showTip.safeBind(this);
	this.eventHide = this.hideTip.safeBind(this);

	this.element.observe('mousemove', this.eventShow);
	this.element.observe('mouseout', this.eventHide);
},

deactivate: function() {
	this.element.stopObserving('mousemove', this.eventShow);
	this.element.stopObserving('mouseout', this.eventHide);
},

buildWrapper: function() {
	this.wrapper = document.createElement('div');
	Element.setStyle(this.wrapper, {
		position: 'absolute',
		zIndex: Tips.zIndex+1,
		display: 'none'
	});

	// IE select fix
	if (Prototype.Browser.IE) {
		this.underlay = document.createElement('iframe');
		this.underlay.src = 'javascript:;';
		Element.setStyle(this.underlay, {
			position: 'absolute',
			display: 'none',
			border: 0,
			margin: 0,
			opacity: 0.01,
			padding: 0,
			background: 'none',
			zIndex: Tips.zIndex
		});
	}
},

buildTip: function() {
	if(Prototype.Browser.IE) document.body.appendChild(this.underlay); // IE selectbox fix

	// add the tooltip
	this.tooltip = this.wrapper.appendChild(document.createElement('div'));
	this.tooltip.className = this.options.className;
	this.tooltip.style.position = 'relative';

	// add the title
	if (this.options.title) {
		this.title = this.tooltip.appendChild(document.createElement('div'));
		this.title.className = 'title';
		Element.update(this.title, this.options.title);
	}

	// content
	this.tip = this.tooltip.appendChild(document.createElement('div'));
	this.tip.className = 'content';
	Element.update(this.tip, this.content);

	// add wrapper to the body
	document.body.appendChild(this.wrapper);

	// prepare for effects
	var w = this.wrapper.getDimensions();
	this.wrapper.setStyle({ width: w.width+'px', height: w.height+'px' });
	if (Prototype.Browser.IE) this.underlay.setStyle({ width: w.width+'px', height: w.height+'px' });
	Element.hide(this.tooltip);
},

showTip: function(event){
	if (!this.tooltip) this.buildTip();
	this.positionTip(event); // follow mouse
	if (this.wrapper.visible() && this.options.effect != 'appear') return;

	if (Prototype.Browser.IE) this.underlay.show(); // IE select fix
	this.wrapper.show();

	if (!this.options.effect) {
		this.tooltip.show();
	} else {
		// stop running effect
		if (this.activeEffect) Effect.Queues.get(this.queue.scope).remove(this.activeEffect);
		// start new
		this.activeEffect = Effect[Effect.PAIRS[this.options.effect][0]](this.tooltip, { duration: this.options.duration, queue: this.queue});
	}
},

hideTip: function(event){
	if(!this.wrapper.visible()) return;

	if (!this.options.effect) {
		if (Prototype.Browser.IE) { this.underlay.hide(); } // select fix
		this.tooltip.hide();
		this.wrapper.hide();
	}
	else {
		// stop running effect
		if (this.activeEffect) Effect.Queues.get(this.queue.scope).remove(this.activeEffect);
		// start new
		this.activeEffect = Effect[Effect.PAIRS[this.options.effect][1]](this.tooltip, { duration: this.options.duration, queue: this.queue, afterFinish: function(){
			if (Prototype.Browser.IE) this.underlay.hide(); // select fix
			this.wrapper.hide();
		}.bind(this)});
	}
},

positionTip: function(event){
	// calculate
	//alert(this.options.offset.x)
	//	alert(this.options.offset.y)

	var offset = {'left': this.options.offset.x,'top': this.options.offset.y};
	var targetPosition = Position.cumulativeOffset(this.target);
	var tipd = this.wrapper.getDimensions();
	var pos = {
			'left': (this.options.fixed) ? targetPosition[0] : Event.pointerX(event),
					'top': (this.options.fixed) ? targetPosition[1] : Event.pointerY(event)
	}

	// add offsets
	pos.left += offset.left;
	pos.top += offset.top;

	if (this.options.hook) {
		var dims = {'target': this.target.getDimensions(), 'tip': tipd}
		var hooks = {'target': Position.cumulativeOffset(this.target), 'tip': Position.cumulativeOffset(this.target)}

		for(var z in hooks) {
			switch(this.options.hook[z]){
			case 'topRight':
				hooks[z][0] += dims[z].width;
				break;
			case 'bottomLeft':
				hooks[z][1] += dims[z].height;
				break;
			case 'bottomRight':
				hooks[z][0] += dims[z].width;
				hooks[z][1] += dims[z].height;
				break;
			}
		}

		// move based on hooks
		pos.left += -1*(hooks.tip[0] - hooks.target[0]);
		pos.top += -1*(hooks.tip[1] - hooks.target[1]);
	}

	// move tooltip when there is a different target when following mouse
	if (!this.options.fixed && this.element !== this.target) {
		var elementPosition = Position.cumulativeOffset(this.element);
		pos.left += -1*(elementPosition[0] - targetPosition[0]);
		pos.top += -1*(elementPosition[1] - targetPosition[1]);
	}

	if (!this.options.fixed && this.options.viewport) {
		var scroll = this.getScrollOffsets();
		var viewport = this.viewportSize();
		var pair = {'left': 'width', 'top': 'height'};

		for(var z in pair) {
			if ((pos[z] + tipd[pair[z]] - scroll[z]) > viewport[pair[z]]) {
				pos[z] = pos[z] - tipd[pair[z]] - 2*offset[z];
			}
		}
	}

	// position
	this.wrapper.setStyle({
		left: pos.left + 'px',
		top: pos.top + 'px'
	});

	if (Prototype.Browser.IE) this.underlay.setStyle({ left: pos.left+'px', top: pos.top+'px' });
},

// Functions below hopefully won't be needed with prototype 1.6
viewportWidth: function(){
	if (Prototype.Browser.Opera) return document.body.clientWidth;
	return document.documentElement.clientWidth;
},

viewportHeight: function(){
	if (Prototype.Browser.Opera) return document.body.clientHeight;
	if (Prototype.Browser.WebKit) return this.innerHeight;
	return document.documentElement.clientHeight;
},

viewportSize : function(){
	return {'height': this.viewportHeight(), 'width': this.viewportWidth()};
},

getScrollLeft: function(){
	return this.pageXOffset || document.documentElement.scrollLeft;
},

getScrollTop: function(){
	return this.pageYOffset || document.documentElement.scrollTop;
},

getScrollOffsets: function(){
	return {'left': this.getScrollLeft(), 'top': this.getScrollTop()}
}
}

/* fix for $A is not defined on Firefox */
Function.prototype.safeBind = function() {
	var __method = this, args = $A(arguments), object = args.shift();
	return function() {
		if (typeof $A == 'function')
			return __method.apply(object, args.concat($A(arguments)));
	}
}