/**
 * m5LazyDisplay
 *
 * @author       nori (norimania@gmail.com)
 * @copyright    5509 (http://5509.me/)
 * @license      The MIT License
 * @link         https://github.com/5509/m5lazydisplay
 *
 * @Modified     2011-03-05 10:49
 *
 */
;(function($) {

	$.fn.m5LazyDisplay = function(options) {
		var _this = this,
			thisLen = _this.length,
			scrollPos = document.body.scrollTop || document.documentElement.scrollTop,
			clientHeight = $("html").attr("clientHeight"),
			line = clientHeight,
			c = $.extend({
				posFix: 0,
				duration: 400
			}, options),
			imgObjs = [],
			currentImg = 0;
			
		for ( var i=0; i<_this.length; i++ ) {
			imgObjs[i] = {};
			imgObjs[i].y = $(_this[i]).offset().top;
			imgObjs[i].obj = $(_this[i]);
			
			if ( (scrollPos + clientHeight) < imgObjs[i].y ) {
				imgObjs[i].obj.css("opacity", 0);
			} else {
				currentImg++;
			}
		}
		
		imgObjs.sort(
			function(a, b) {
				return a.y - b.y;
			}
		);
		
		$(window)
			.resize(function() {
				clientHeight = document.body.clientHeight || document.documentElement.clientHeight;
			})
			.bind("scroll.LazyDisplayScroll", function() {
				if ( currentImg === thisLen ) {
					$(window).unbind("scroll.LazyDisplayScroll");
					return false;
				}
				scrollPos = document.body.scrollTop || document.documentElement.scrollTop;
				while ( imgObjs[currentImg].y <= (scrollPos + c.posFix + clientHeight) ) {
					imgObjs[currentImg].obj.fadeTo(c.duration, 1);
					currentImg++;
					if ( currentImg === thisLen ) {
						$(window).unbind("scroll.LazyDislayscroll");
						break;
					}
				}
			});
	}

})(jQuery);