/*
 *  description: 漂浮广告
 *  author: jjc
 *  date: 2012.07.04
 */
;(function ( $, window, document, undefined ) {
    var pluginname = 'floatingad';
    var defaults = {
		step: 1,
		delay: 50, 
		islinkclosed: false,
		onclose: function(elem){}
    };
    var ads = {
    	linkurl: '#',
    	'z-index': '100',
    	'closed-icon': '',
    	imgheight: '',
    	imgwidth: '',
    	title: '',
    	img: '#',
    	linkwindow: '_blank',
    	headfilter: 0.2
    };

    function plugin(element, options) {
        this.element = element;
        this.options = $.extend(
        	{}, 
        	defaults, 
        	options, 
        	{
        		width: $(window).width(),
				height: $(window).height(),
        		xpos: this.getrandomnum(0, $(window).width() - $(element).innerwidth()), 
				ypos: this.getrandomnum(0, 300),
				yon: this.getrandomnum(0, 1),
				xon: this.getrandomnum(0, 1),
				ypath: this.getrandomnum(0, 1),
				xpath: this.getrandomnum(0, 1),
				hoffset: $(element).innerheight(),
				woffset: $(element).innerwidth(),
				fn: function(){},
				interval: 0
			}
        );
        this._defaults = defaults;
        this._name = pluginname;
        
        this.init();
    }

    plugin.prototype = {
    	init: function () {
    		var elem = $(this.element);
    		var defaults = this.options;
    		var p = this;
    		var xflag = 0;
    		var yflag = 0;
    		
    		elem.css({"left": defaults.xpos + p.scrollx(), "top": defaults.ypos + p.scrolly()});
    		defaults.fn = function(){
		    	defaults.width = $(window).width();
				defaults.height = $(window).height();
				
				if(xflag == p.scrollx() && yflag == p.scrolly()){
					elem.css({"left": defaults.xpos + p.scrollx(), "top": defaults.ypos + p.scrolly()});
					if (defaults.yon)
						defaults.ypos = defaults.ypos + defaults.step;
					else
						defaults.ypos = defaults.ypos - defaults.step;
				
					if (defaults.ypos <= 0) {
						defaults.yon = 1;
						defaults.ypos = 0;
					}
					if (defaults.ypos >= (defaults.height - defaults.hoffset)) {
						defaults.yon = 0;
						defaults.ypos = (defaults.height - defaults.hoffset);
					}
					
					if (defaults.xon) 
						defaults.xpos = defaults.xpos + defaults.step;
					else
						defaults.xpos = defaults.xpos - defaults.step;
		
					if (defaults.xpos <= 0) {
						defaults.xon = 1;
						defaults.xpos = 0;
					}
					if (defaults.xpos >= (defaults.width - defaults.woffset)) {
						defaults.xon = 0;
						defaults.xpos = (defaults.width - defaults.woffset);
					}
				}
				yflag = $(window).scrolltop();
				xflag = $(window).scrollleft();
   			};
   			this.run(elem, defaults);
    	},
    	run: function(elem, defaults){
    		this.start(elem, defaults);
    		this.adevent(elem,defaults);
    	},
    	start: function(elem, defaults){
    		elem.find('div.close').hide();
    		defaults.interval = window.setinterval(defaults.fn,  defaults.delay);
    		window.settimeout(function(){elem.show();}, defaults.delay);
    	},
    	getrandomnum: function (min, max){  
			var range = max - min;  
			var rand = math.random();  
			return(min + math.round(rand * range));  
		},
		getpath: function(on){
			return on ? 0 : 1;
		},
		clear: function(elem, defaults){
			elem.find('div.close').show();
			window.clearinterval(defaults.interval);
		},
		close: function(elem, defaults, isclose){
			elem.unbind('hover');
  			elem.hide();
  			if(isclose)
				defaults.onclose.call(elem);
		},
		adevent: function(elem, defaults){
			var obj = {
				elem: this,
			  	fn_close: function() {
			   		this.elem.close(elem, defaults, true);
			  	},
			  	fn_clear: function() {
			  		if(this.elem.options.islinkclosed)
			  			this.elem.close(elem, defaults, false);
			  	}
			};
			
    		elem.find('div.button').bind('click', jquery.proxy(obj, "fn_close"));
    		
    		elem.find('a').bind('click', jquery.proxy(obj, "fn_clear"));
    		
    		var stop = {
				elem: this,
			  	over: function(){
			    	this.elem.clear(elem, defaults);
			  	},
			  	out: function(){
					this.elem.start(elem, defaults);
			  	}
			};
    		
    		elem.hover(
			    jquery.proxy(stop, "over"),
				jquery.proxy(stop, "out")
			);
		},
		scrollx: function(){
			var de = document.documentelement;
			return self.pagexoffset || (de && de.scrollleft) || document.body.scrollleft;
		},
		scrolly: function(){
			var de = document.documentelement;
			return self.pageyoffset || (de && de.scrolltop) || document.body.scrolltop;
		}
	};
    $.fn.floatingad = function(options) {
        return this.children("div").each(function (i, elem) {
            if (!$.data(this, 'plugin_' + pluginname)) {
                $.data(this, 'plugin_' + pluginname, new plugin(this, options));
            }
        });
    };
	$.floatingad = function(options){
		
		if(options){
	    	if(options.ad){
	    		var addiv = $('#' + pluginname);
	    		
	    		if(addiv.length <= 0)
		    		addiv = $('<div>', {
		    			'id': pluginname,
		    			'class': pluginname
		    		}).appendto('body');
		    		
	    		for(var i in options.ad){
	    			
	    			var ad = options.ad[i];
	    			ad = $.extend({}, ads, ad);
	    			//漂浮层
	    			var div = $('<div>', {
	    				'class': 'ad'
	    			});
	    			
	    			div.css("z-index", ad['z-index']);
	    			
	    			//关闭层
	    			var closediv = $('<div>', {
	    				'class': 'close'
	    			});
	    			$('<div>', {
	    				'class': 'opacity',
	    				'style': 'opacity: ' + ad.headfilter + ';filter: alpha(opacity = ' + ad.headfilter*100 + ');'
	    			}).appendto(closediv);
	    			
	    			$('<div>', {
	    				'class': 'text'
	    			}).append(
	    				$('<div>', {
	    					'class': 'title',
	    					'text': ad.title
	    				})
	    			).append(
	    				$('<div>', {
	    					'class': 'button',
	    					'style': ad['closed-icon'] ? 'background:url("' + ad['closed-icon'] + '") no-repeat;' : ''
	    				})
	    			).appendto(closediv);
	    			
	    			closediv.appendto(div);
	    			
	    			//内容层
	    			var content = $('<div>');
	    			
	    			$('<a>', {
	    				href: ad.linkurl,
	    				target: ad.linkwindow,
	    				title: ad.title
	    			}).append(
	    				$('<img>', {
	    					'src': ad.img,
	    					'style': (ad.imgheight ? 'height:' + ad.imgheight + 'px;' : '') + 
	    					         (ad.imgwidth ? 'width:' + ad.imgwidth + 'px;' : '')
	    				})
	    			).appendto(content);
	    			
	    			content.appendto(div);
	    			
	    			div.appendto(addiv);
	    		}
	    		delete options.ad;
	    		$('#' + pluginname).floatingad(options);
	    	}
	    } 
		else
	      	$.error('漂浮广告错误!');
	};
})(jquery, window, document);