/*
 * Tooltip - jQuery plugin  for styled tooltips
 *
 * Copyright (c) 2006 Jörn Zaefferer, Stefan Petre
 *
 * Dual licensed under the MIT and GPL licenses:
 *   http://www.opensource.org/licenses/mit-license.php
 *   http://www.gnu.org/licenses/gpl.html
 *
 */

/**
 * Display a customized tooltip instead of the default one
 * for every selected element. The tooltip behaviour mimics
 * the default one, but lets you style the tooltip and
 * specify the delay before displaying it.
 *
 * In addition, it displays the href value, if it is available.
 * 
 * To style the tooltip, use these selectors in your stylesheet:
 *
 * #tooltip - The tooltip container
 *
 * #tooltip h3 - The tooltip title
 *
 * #tooltip p.body - The tooltip body, shown when using showBody
 *
 * #tooltip p.url - The tooltip url, shown when using showURL
 *
 * @example $('a, input, img').Tooltip();
 * @desc Shows tooltips for anchors, inputs and images, if they have a title
 *
 * @example $('label').Tooltip({
 *   delay: 0,
 *   track: true,
 *   event: "click"
 * });
 * @desc Shows tooltips for labels with no delay, tracking mousemovement, displaying the tooltip when the label is clicked.
 *
 * @example // modify global settings
 * $.extend($.fn.Tooltip.defaults, {
 * 	track: true,
 * 	delay: 0,
 * 	showURL: false,
 * 	showBody: " - ",
 *  fixPNG: true
 * });
 * // setup fancy tooltips
 * $('a.pretty').Tooltip({
 * 	 extraClass: "fancy"
 * });
 $('img.pretty').Tooltip({
 * 	 extraClass: "fancy-img",
 * });
 * @desc This example starts with modifying the global settings, applying them to all following Tooltips; Afterwards, Tooltips for anchors with class pretty are created with an extra class for the Tooltip: "fancy" for anchors, "fancy-img" for images
 *
 * @param Object settings (optional) Customize your Tooltips
 * @option Number delay The number of milliseconds before a tooltip is display, default is 250
 * @option String event The event on which the tooltip is displayed, default is "mouseover", "click" works fine, too
 * @option Boolean track If true, let the tooltip track the mousemovement, default is false
 * @option Boolean showURL If true, shows the href or src attribute within p.url, default is true
 * @option String showBody If specified, uses the String to split the title, displaying the first part in the h3 tag, all following in the p.body tag, separated with <br/>s, default is null
 * @option String extraClass If specified, adds the class to the tooltip helper, default is null
 * @option Boolean fixPNG If true, fixes transparent PNGs in IE, default is false
 *
 * @name Tooltip
 * @type jQuery
 * @cat Plugins/Tooltip
 * @author Jörn Zaefferer (http://bassistance.de)
 */
(function($) {
	
	// the tooltip element
	var helper,current;
	
	// the public plugin method
	$.fn.Tooltip = function(settings) {
		// setup configuration
		// TODO: allow multiple arguments to extend, see bug #344
		settings = $.extend($.extend({}, arguments.callee.defaults), settings || {});
	
		// there can be only one tooltip helper
		if( !helper ) {
			// create the helper, h3 for title, div for url
			helper = $('<div id="tooltip"></div>')
				.hide()
				.css({ position: 'absolute', zIndex: 3000 })
				.appendTo('body');
		}
		
		// bind events for every selected element with a title attribute
		$(this)
			.each(function() {
				this.tSettings = settings;
			})
			// bind events
			.bind("mouseover", save)
			.bind(settings.event, handle);
		return this;
	};
	
	// main event handler to start showing tooltips
	function handle(event) {
		// show helper, either with timeout or on instant
		show();
		
		// if selected, update the helper position when the mouse moves
		if(this.tSettings.track) $('body').bind('mousemove', update);
			
		// update at least once
		update(event);
		
		// hide the helper when the mouse moves out of the element
		$(this).bind('mouseout', hide);
	}
	
	// save elements title before the tooltip is displayed
	function save() {
		// save current
		current = this;		
		// save title, remove from element and set to helper
		helper.html(this.tSettings.body.html());
	}
	
	// delete timeout and show helper
	function show() {
		tID = null;
		helper.show();
		update();
	}
	
	/**
	 * callback for mousemove
	 * updates the helper position
	 * removes itself when no current element
	 */
	function update(event)	{
		// if no current element is available, remove this listener
		if( current == null ) {
			$('body').unbind('mousemove', update);
			return;	
		}
		
		var left = helper[0].offsetLeft;
		var top = helper[0].offsetTop;
		if(event) {
			// get the current mouse position
			function pos(c) {
				var p = c == 'X' ? 'Left' : 'Top';
				return event['page' + c] || (event['client' + c] + (document.documentElement['scroll' + p] || document.body['scroll' + p])) || 0;
			}
			// position the helper 15 pixel to bottom right, starting from mouse position
			left = pos('X') + 15;
			top = pos('Y') + 0;
			helper.css({
				left: left + 'px',
				top: top + 'px'
			});
		}
	}
	
	// hide helper and restore added classes and the title
	function hide() {
		// no more current element
		current = null;
		helper.hide();
		// restore title and remove this listener
		$(this).unbind('mouseout', hide);
	}
	
	// define global defaults, editable by client
	$.fn.Tooltip.defaults = {
		delay: 250,
		event: "mouseover",
		track: false,
		showURL: true,
		showBody: null,
		extraClass: null,
		fixPNG: false
	};

})(jQuery);