(function ($) {
	$.fn.tipsy = function (options) {

		options = $.extend({}, $.fn.tipsy.defaults, options);

		return this.each(function () {

			if ($(this).attr('alt') || typeof ($(this).attr('original-alt')) != 'string') {
				$(this).attr('original-alt', $(this).attr('alt') || '').removeAttr('alt');
			}

			if ($(this).attr('title') || typeof ($(this).attr('original-title')) != 'string') {
				$(this).attr('original-title', $(this).attr('title') || '').removeAttr('title');
			}
			
			var opts = $.fn.tipsy.elementOptions(this, options);

			$(this).hover(function () {

				$.data(this, 'cancel.tipsy', true);
				var tip = $.data(this, 'active.tipsy');
				if (!tip) {
					tip = $('<div class="tipsy"><div class="tipsy-inner"/></div>');
					tip.css({ position: 'absolute', zIndex: 100000 });
					$.data(this, 'active.tipsy', tip);
				}

				var title;
				if (typeof opts.title == 'string') {
					title = $(this).attr(opts.title == 'title' ? 'original-title' : opts.title);
				} else if (typeof opts.title == 'function') {
					title = opts.title.call(this);
				}

				tip.find('.tipsy-inner')[opts.html ? 'html' : 'text'](title || opts.fallback);

				var pos = $.extend({}, $(this).offset(), { width: this.offsetWidth, height: this.offsetHeight });
				tip.get(0).className = 'tipsy'; // reset classname in case of dynamic gravity
				tip.remove().css({ top: 0, left: 0, visibility: 'hidden', display: 'block' }).appendTo(document.body);
				var actualWidth = tip[0].offsetWidth, actualHeight = tip[0].offsetHeight;
				var gravity = (typeof opts.gravity == 'function') ? opts.gravity.call(this) : opts.gravity;

				switch (gravity.charAt(0)) {
					case 'n':
						tip.css({ top: pos.top + pos.height, left: pos.left + pos.width / 2 - actualWidth / 2 }).addClass('tipsy-north');
						break;
					case 's':
						tip.css({ top: pos.top - actualHeight, left: pos.left + pos.width / 2 - actualWidth / 2 }).addClass('tipsy-south');
						break;
					case 'e':
						tip.css({ top: pos.top + pos.height / 2 - actualHeight / 2, left: pos.left - actualWidth }).addClass('tipsy-east');
						break;
					case 'w':
						tip.css({ top: pos.top + pos.height / 2 - actualHeight / 2, left: pos.left + pos.width }).addClass('tipsy-west');
						break;
				}

				if (opts.fade) {
					tip.css({ opacity: 0, display: 'block', visibility: 'visible' }).animate({ opacity: 0.8 });
				} else {
					tip.css({ visibility: 'visible' });
				}

			}, function () {
				$.data(this, 'cancel.tipsy', false);
				var self = this;
				setTimeout(function () {
					if ($.data(this, 'cancel.tipsy')) return;
					var tip = $.data(self, 'active.tipsy');
					if (opts.fade) {
						tip.stop().fadeOut(function () { $(this).remove(); });
					} else {
						tip.remove();
					}
				}, 100);

			});

		});

	};

	// Overwrite this method to provide options on a per-element basis.
	// For example, you could store the gravity in a 'tipsy-gravity' attribute:
	// return $.extend({}, options, {gravity: $(ele).attr('tipsy-gravity') || 'n' });
	// (remember - do not modify 'options' in place!)
	$.fn.tipsy.elementOptions = function (ele, options) {
		return $.metadata ? $.extend({}, options, $(ele).metadata()) : options;
	};

	$.fn.tipsy.defaults = {
		fade: false,
		fallback: '',
		gravity: 'n',
		html: false,
		title: 'title'
	};

	$.fn.tipsy.autoNS = function () {
		return $(this).offset().top > ($(document).scrollTop() + $(window).height() / 2) ? 's' : 'n';
	};

	$.fn.tipsy.autoWE = function () {
		return $(this).offset().left > ($(document).scrollLeft() + $(window).width() / 2) ? 'e' : 'w';
	};

})(jQuery);