﻿(function($) {

	$.fn.TextAreaExpander = function(minHeight, maxHeight) {

		var hCheck = !($.browser.msie || $.browser.opera);

		function ResizeTextarea(e) {

			e = e.target || e;

			var vlen = e.value.length, ewidth = e.offsetWidth;
			if (vlen != e.valLength || ewidth != e.boxWidth) {

				if (hCheck && (vlen < e.valLength || ewidth != e.boxWidth)) e.style.height = "0px";
				var h = Math.max(e.expandMin, Math.min(e.scrollHeight, e.expandMax));

				e.style.overflow = (e.scrollHeight > h ? "auto" : "hidden");
				e.style.height = h + "px";

				e.valLength = vlen;
				e.boxWidth = ewidth;
			}

			return true;
		};

		this.each(function() {

			if (this.nodeName.toLowerCase() != "textarea") return;

			var p = this.className.match(/expand(\d+)\-*(\d+)*/i);
			this.expandMin = minHeight || (p ? parseInt('0'+p[1], 10) : 0);
			this.expandMax = maxHeight || (p ? parseInt('0'+p[2], 10) : 99999);

			ResizeTextarea(this);

			if (!this.Initialized) {
				this.Initialized = true;
				$(this).css("padding-top", 0).css("padding-bottom", 0);
				$(this).bind("keyup", ResizeTextarea).bind("focus", ResizeTextarea);
			}
		});

		return this;
	};

})(jQuery);


jQuery(document).ready(function() {
	jQuery("textarea[class*=expand]").TextAreaExpander();
});
