/*
 * Create an Image fading slider to the popular Flash fader

 * ImageFadingSlider is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 3 of the License.
 *
 * ImageFadingSlider is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * @license http://www.gnu.org/licenses/gpl-3.0.txt GPL
 *
 * You should have received a copy of the GNU General Public License
 * along with imagefader; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * @name		ImageFadingSlider
 * @author		Youngjae Ji
 * @contact		zirho6@gmail.com
 * @version		1.0
 * @date		Nov 7 2009
 * @type    	jQuery plugin
 *
 * The latest version of ImageFadingSlider can be obtained from:
 * http://www.wingtech.co.kr/imagefader
 *
 */

(function($) {
	//
	// plugin definition
	//
	$.fn.imageFadingSlider = function(options) {
		// build main options before element iteration
		var main_opts = $.extend({}, $.fn.imageFadingSlider.defaults, options);

		// iterate and reformat each matched element
		return this.each(function() {
			var $this = $(this);
			var currItem = $("img:eq(0)", $this);
			var opts = $.metadata ? $.extend({}, main_opts, $this.metadata()) : main_opts;
			var nextEasing;
						
			$this
				.css("background","transparent")
				.css("width",opts.item_width)
				.css("height",opts.item_height)
				.css("border","3px #888 solid")
				.css("overflow","hidden")
				.css("display","block");

			$("img", $this)
				.css("width",opts.item_width+opts.dist)
				.css("height",opts.item_height+opts.dist)
				.css("margin-left",-opts.dist)
				.css("margin-top",-opts.dist)
				.css("position","absolute")
				.css("top","0px")
				.css("left","0px");

			if (opts.total_time - opts.fading_time - 500 < 0 ) opts.fading_time = opts.total_time - 500;

			if(opts.easing == "random") thisEasing = $.fn.imageFadingSlider.easing[ Math.floor( Math.random()*$.fn.imageFadingSlider.easing.length ) ];
			else thisEasing = $.fn.imageFadingSlider.easing[opts.easing];

			doFadingEffect(currItem, thisEasing);

			function doFadingEffect(iCurrItem, iEasing){
				
				//make the image visible
				iCurrItem
					.css("margin-top", -(iEasing[0]*opts.dist))
					.css("margin-left", -(iEasing[1]*opts.dist))
					.css("display", "block")
					.css("z-index", 100);
				
				//reserve first image fade
				setTimeout(function(){
					iCurrItem.animate({"opacity": "hide"}, { duration: opts.fading_time, queue: false});
				}, opts.total_time - opts.fading_time - 500);

				//make sibling invisible
				iCurrItem.siblings()
					.css("display", "none")
					.css("z-index", 98);
					
				if(opts.easing == "random") nextEasing = $.fn.imageFadingSlider.easing[ Math.floor( Math.random()*$.fn.imageFadingSlider.easing.length ) ];
				else nextEasing = $.fn.imageFadingSlider.easing[opts.easing];

				//make the next image visible
				var iNextImage = getNextImg(iCurrItem);
				iNextImage
					.css("margin-top", -(nextEasing[0]*opts.dist))
					.css("margin-left", -(nextEasing[1]*opts.dist))
					.css("display", "block")
					.css("z-index", 99);

				//make the image move
				iCurrItem.animate({"marginTop": -(iEasing[2]*opts.dist),"marginLeft": -(iEasing[3]*opts.dist)}, opts.total_time, function(){ doFadingEffect(iNextImage, nextEasing);} );				
			};
			
			// get next image circular
			function getNextImg(cur){
				var next = cur.next();
				if(!next.size()) next = $("img:eq(0)", cur.parent());
				return next;
			};
		});
	};

	//
	// plugin defaults
	//
	$.fn.imageFadingSlider.defaults = {
		item_width: 100,
		item_height: 100,
		dist: 40,
		total_time: 6000,
		fading_time: 2000,
		easing: "4"
	};
	//
	// plugin easings
	//
	$.fn.imageFadingSlider.easing = [
		["1", "0", "0", "0"],
		["0", "1", "0", "0"],
		["0", "0", "1", "0"],
		["0", "0", "0", "1"],

		["1", "1", "0", "0"],
		["1", "0", "0", "1"],
		["0", "1", "1", "0"],
		["0", "0", "1", "1"]
	];
//
// end of closure
//
})(jQuery);