/*
 * Copyright (c) 2006 Jonathan Weiss <jw@innerewut.de>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */


/* tooltip-0.1.js - Small tooltip library on top of Prototype 
 * by Jonathan Weiss <jw@innerewut.de> distributed under the BSD license. 
 *
 * Unlike other libraries it does not declare its own tooltip 
 * div or window. It relies on an already existing div or element defined by you to display as 
 * the tooltip. This element will be placed (and shown) near the mouse pointer when a trigger-element is moused-over.
 * 
 *
 * Usage: 
 *   <script src="/javascripts/prototype.js" type="text/javascript"></script>
 *   <script src="/javascripts/tooltip.js" type="text/javascript"></script>
 *   <script type="text/javascript">
 *     var my_tooltip = new Tooltip('id_of_trigger_element', 'id_of_tooltip_to_show_element')
 *   </script>
 * 
 * Now whenever you trigger a mouseOver on the `trigger` element, the tooltip element will
 * be shown. On o mouseOut the tooltip disappears. 
 * 
 * Example:
 * 
 *   <script src="/javascripts/prototype.js" type="text/javascript"></script>
 *   <script src="/javascripts/scriptaculous.js" type="text/javascript"></script>
 *   <script src="/javascripts/tooltip.js" type="text/javascript"></script>
 *
 *   <div id='tooltip' style="display:none; margin: 5px; background-color: red;">
 *     Detail infos on product 1....<br />
 *   </div>
 *
 *   <div id='product_1'>
 *     This is product 1
 *   </div>
 *
 *   <script type="text/javascript">
 *     var my_tooltip = new Tooltip('product_1', 'tooltip')
 *   </script>
 *
 * You can use my_tooltip.destroy() to remove the event observers and thereby the tooltip.
 */

var Tooltip = Class.create();
Tooltip.prototype = {
    initialize: function(element, tool_tip) {
	var options = Object.extend({
		default_css: false,
		margin: "0px",
		padding: "5px",
		backgroundColor: "#d6d6fc",
		delta_x: 5,
		delta_y: 5,
		zindex: 1000
	    }, arguments[1] || {});

	this.element      = $(element);
	this.tool_tip     = $(tool_tip);

	this.options      = options;

	// hide the tool-tip by default
	this.tool_tip.hide();

	this.eventMouseOver = this.showTooltip.bindAsEventListener(this);
	this.eventMouseOut   = this.hideTooltip.bindAsEventListener(this);

	this.registerEvents();
    },

    destroy: function() {
	Event.stopObserving(this.element, "mouseover", this.eventMouseOver);
	Event.stopObserving(this.element, "mouseout", this.eventMouseOut);
    },

    registerEvents: function() {
	Event.observe(this.element, "mouseover", this.eventMouseOver);
	Event.observe(this.element, "mouseout", this.eventMouseOut);
    },

    showTooltip: function(event){
	Event.stop(event);
	// get Mouse position
	var mouse_x = Event.pointerX(event);
	var mouse_y = Event.pointerY(event);	
	
	// decide if wee need to switch sides for the tooltip
	var dimensions = Element.getDimensions( this.tool_tip );
	var element_width = dimensions.width;
	var element_height = dimensions.height;
	
	if ( (element_width + mouse_x) >= ( this.getWindowWidth() - this.options.delta_x) ){ // too big for X
	    mouse_x = mouse_x - element_width;
	    // apply delta to make sure that the mouse is not on the tool-tip
	    mouse_x = mouse_x - this.options.delta_x;
	} else {
	    mouse_x = mouse_x + this.options.delta_x;
	}
	
	if ( (element_height + mouse_y) >= ( this.getWindowHeight() - this.options.delta_y) ){ // too big for Y
	    mouse_y = mouse_y - element_height;
	    // apply delta to make sure that the mouse is not on the tool-tip
	    mouse_y = mouse_y - this.options.delta_y;
	} else {
	    mouse_y = mouse_y + this.options.delta_y;
	} 
	
	// now set the right styles
	this.setStyles(mouse_x, mouse_y);
	
		
	// finally show the Tooltip
	//new Effect.Appear(this.tool_tip);
	new Element.show(this.tool_tip);

    },
  
    setStyles: function(x, y){
	
	// compute right offset for element
	parent=this.element.getOffsetParent();
	offset=parent.positionedOffset();
	x=x-offset.left;
	y=y-offset.top;

	// set the right styles to position the tool tip
	Element.setStyle(this.tool_tip, { position:'absolute',
					  top:y + "px",
					  left:x + "px",
					  zindex:this.options.zindex
	    });
	
	// apply default theme if wanted
	if (this.options.default_css){
	    Element.setStyle(this.tool_tip, { margin:this.options.margin,
			padding:this.options.padding,
			backgroundColor:this.options.backgroundColor,
			zindex:this.options.zindex
			});	
	}	
    },

    hideTooltip: function(event){
	//new Effect.Fade(this.tool_tip);
	new Element.hide(this.tool_tip);
    },

    getWindowHeight: function(){
	var innerHeight;
	if (navigator.appVersion.indexOf('MSIE')>0) {
	    innerHeight = document.body.clientHeight;
	} else {
	    innerHeight = window.innerHeight;
	}
	return innerHeight;	
    },
 
    getWindowWidth: function(){
	var innerWidth;
	if (navigator.appVersion.indexOf('MSIE')>0) {
	    innerWidth = document.body.clientWidth;
	} else {
	    innerWidth = window.innerWidth;
	}
	return innerWidth;	
    }

}