/* 
 * Auto Expanding Text Area (1.2.2)
 * by Chrys Bader (www.chrysbader.com)
 * chrysb@gmail.com
 *
 * Special thanks to:
 * Jake Chapa - jake@hybridstudio.com
 * John Resig - jeresig@gmail.com
 *
 * Copyright (c) 2008 Chrys Bader (www.chrysbader.com)
 * Dual licensed under the MIT (MIT-LICENSE.txt)
 * and GPL (GPL-LICENSE.txt) licenses.
 *
 *
 * NOTE: This script requires jQuery to work.  Download jQuery at www.jquery.com
 * 
 * 
 * F-engine modifications:
 * 
 * Adapted to ajax web pages, now it creates the div class autogrow-dummy once instead of one per call.
 * Onload height detection fixed when text height is bigger or equal to textarea max_height.
 */
 
(function(jQuery) {
		  
	var self = null;
 
	jQuery.fn.autogrow = function(o)
	{		
		return this.each(function() {
			new jQuery.autogrow(this, o);
		});
	};
	

    /**
     * The autogrow object.
     *
     * @constructor
     * @name jQuery.autogrow
     * @param Object e The textarea to create the autogrow for.
     * @param Hash o A set of key/value pairs to set as configuration properties.
     * @cat Plugins/autogrow
     */
	
	jQuery.autogrow = function (e, o)
	{
		this.options		  	= o || {};
		this.dummy			  	= jQuery('div.autogrow-dummy');
		this.interval	 	  	= null;
		this.line_height	  	= this.options.lineHeight || parseInt(jQuery(e).css('line-height'));
		this.min_height		  	= this.options.minHeight || parseInt(jQuery(e).css('min-height'));
		this.max_height		  	= this.options.maxHeight || parseInt(jQuery(e).css('max-height'));;
		this.textarea		  	= jQuery(e);

		if(this.line_height == NaN)
		  this.line_height = 0;

		// Only one textarea activated at a time, the one being used
		this.init();
	};

	jQuery.autogrow.fn = jQuery.autogrow.prototype = {
    autogrow: '1.2.2'
  };

	jQuery.autogrow.fn.extend = jQuery.autogrow.extend = jQuery.extend;

	jQuery.autogrow.fn.extend({

		init: function() {			
			var self = this;			
			this.textarea.css({overflow: 'hidden', display: 'block'});
			this.textarea.bind('focus', function() { self.startExpand() } ).bind('blur', function() { self.stopExpand() });

			if (this.dummy.length == 0) {

				jQuery('body').append('<div class="autogrow-dummy"></div>');
				this.dummy = jQuery('div.autogrow-dummy');

				this.dummy.css({
					'overflow-x' : 'hidden',
					'position'   : 'absolute',
					'top'        : 0,
					'left'		 : -9999
				});	
			}
				
			this.checkExpand();
		},

		startExpand: function() {				
		  var self = this;
		  
		  this.textarea.css('width', this.textarea.width());	
		  this.interval = window.setInterval(function() {self.checkExpand()}, 300);
		},

		stopExpand: function() {
			clearInterval(this.interval);	
		},

		checkExpand: function() {

			this.dummy.css({
							'font-size'  : this.textarea.css('font-size'),
							'font-family': this.textarea.css('font-family'),
							'width'      : this.textarea.css('width'),
							'padding'    : this.textarea.css('padding')
							}).appendTo('body');


			// Strip HTML tags
			var html = this.textarea.val().replace(/(<|>)/g, '');

			// IE is different, as per usual
			if ($.browser.msie)
			{
				html = html.replace(/\n/g, '<BR>new');
			}
			else
			{
				html = html.replace(/\n/g, '<br />new');
			}
			
			if (this.dummy.html() != html)
			{
				this.dummy.html(html);	

				if (this.max_height > 0 && (this.dummy.height() >= this.max_height)) {

					this.textarea.css({'overflow-y':'auto', height: this.dummy.height() + 'px'});
					
				} else {
					
					this.textarea.css('overflow-y', 'hidden');
					if (this.textarea.height() < this.dummy.height() || (this.dummy.height() < this.textarea.height()))
					{	
						this.textarea.animate({height: this.dummy.height() + 'px'}, 100);	
					}
					
				}
			}
		}			 
	 });
})(jQuery);