/* Copyright (c) 2008 Brandon Aaron (http://brandonaaron.net)
 * Dual licensed under the MIT (http://www.opensource.org/licenses/mit-license.php) 
 * and GPL (http://www.opensource.org/licenses/gpl-license.php) licenses.
 *
 * Contributions by:
 *   - Karl Swedberg
 */
(function($){$.fn.extend({expandable:function(options){options=$.extend({duration:'normal',interval:750,within:1,by:2,init:false},options);return this.filter('textarea').each(function(){var $this=$(this).css({display:'block',overflow:'hidden'}),minHeight=$this.height(),interval,heightDiff=this.offsetHeight-minHeight,rowSize=(parseInt($this.css('lineHeight'),10)||parseInt($this.css('fontSize'),10)),$div=$('<div style="position:absolute;top:-999px;left:-999px;border-color:#000;border-style:solid;overflow-x:hidden;visibility:hidden;z-index:0;" />').appendTo('body');$.each('borderTopWidth borderRightWidth borderBottomWidth borderLeftWidth paddingTop paddingRight paddingBottom paddingLeft fontSize fontFamily fontWeight fontStyle fontStretch fontVariant wordSpacing lineHeight width'.split(' '),function(i,prop){$div.css(prop,$this.css(prop));});$this.bind('keypress',function(event){if(event.keyCode=='13')check();}).bind('focus blur',function(event){if(event.type=='blur')clearInterval(interval);if(event.type=='focus')interval=setInterval(check,options.interval);});function check(){var text=$this.val(),newHeight,height,usedHeight,usedRows,availableRows;$div.html(text.replace(/\n/g,'&nbsp;<br>').replace(/<(\/?)scrip/g,'<$1scirp'));height=$this[0].offsetHeight-heightDiff;usedHeight=$div[0].offsetHeight-heightDiff;usedRows=Math.floor(usedHeight/rowSize);availableRows=Math.floor((height/rowSize)-usedRows);if(availableRows<=options.within){newHeight=rowSize*(usedRows+Math.max(availableRows,0)+options.by);$this.stop().animate({height:newHeight},options.duration);}else if(availableRows>options.by+options.within){newHeight=Math.max(height-(rowSize*(availableRows-(options.by+options.within))),minHeight);$this.stop().animate({height:newHeight},options.duration);}};if(options.init)check();}).end();}});})(jQuery);