/*
power by: http://www.wxwdesign.cn
*/
//主函�
var s = function() {
	var interv = 5000; //切�间隔时间
	var interv2 = 10; //切�速�
	var opac1 = 30; //文字背景的�明�
	var source = "fade_focus" //焦点轮�图片容器的id�称
	//获�对象
	function getTag(tag, obj) {
		if (obj == null) {
			return document.getElementsByTagName(tag)
		} else {
			return obj.getElementsByTagName(tag)
		}
	}
	function getid(id) {
		return document.getElementById(id)
	};
	var opac = 0,
	j = 0,
	t = 63,
	num, scton = 0,
	timer, timer2, timer3;
	var id = getid(source);
	id.removeChild(getTag("div", id)[0]);
	var li = getTag("li", id);
	var div = document.createElement("div");
	var title = document.createElement("div");
	var span = document.createElement("span");
	var button_list = document.createElement("div");
	button_list.className = "button_list";
	for (var i = 0; i < li.length; i++) {
		var a = document.createElement("a");
		a.innerHTML = i + 1;
		a.onmouseover = function() {
			clearTimeout(timer);
			clearTimeout(timer2);
			clearTimeout(timer3);
			j = parseInt(this.innerHTML) - 1;
			scton = 0;
			t = 63;
			opac = 0;
			fadeon();
		};
		a.className = "button_css";
		a.onmouseout = function() {
			this.className = "button_css";
			sc(j)
		};
		button_list.appendChild(a);
	}
	//控制图层�明�
	function alpha(obj, n) {
		if (document.all) {
			obj.style.filter = "alpha(opacity=" + n + ")";
		} else {
			obj.style.opacity = (n / 100);
		}
	}
	//控制焦点按钮
	/*
	function sc(n) {
		for (var i = 0; i < li.length; i++) {
			button_list.childNodes[0].className = "button1"
		};
		button_list.childNodes[1].className = "button2";
		button_list.childNodes[2].className = "button3";
	}*/
	function sc(n) {
		for (var i = 0; i < li.length; i++) {
			button_list.childNodes[i].className = "button_css";
			button_list.childNodes[i].id="button"+(i+1);
		};
		
		button_list.childNodes[n].className = "button_hover";
	}
	title.className = "img_bottom";
	title.appendChild(span);
	alpha(title, opac1);
	id.className = "focus_d1";
	div.className = "focus_d2";
	id.appendChild(div);
	id.appendChild(title);
	id.appendChild(button_list);
	//�显
	var fadeon = function() {
		opac += 5;
		div.innerHTML = li[j].innerHTML;
		span.innerHTML = getTag("img", li[j])[0].alt;
		alpha(div, opac);
		if (scton == 0) {
			sc(j);
			num = -2;
			scrolltxt();
			scton = 1
		};
		if (opac < 100) {
			timer = setTimeout(fadeon, interv2)
		} else {
			timer2 = setTimeout(fadeout, interv);
		};
	}
	//��
	var fadeout = function() {
		opac -= 5;
		div.innerHTML = li[j].innerHTML;
		alpha(div, opac);
		if (scton == 0) {
			num = 2;
			scrolltxt();
			scton = 1
		};
		if (opac > 0) {
			timer = setTimeout(fadeout, interv2)
		} else {
			if (j < li.length - 1) {
				j++
			} else {
				j = 0
			};
			fadeon()
		};
	}
	//滚动文字
	var scrolltxt = function() {
		t += num;
		span.style.marginTop = t + "px";
		if (num < 0 && t > 3) {
			timer3 = setTimeout(scrolltxt, interv2)
		} else if (num > 0 && t < 62) {
			timer3 = setTimeout(scrolltxt, interv2)
		} else {
			scton = 0
		}
	};
	fadeon();
}
//�始�
window.onload = s;