window.onload = init;
var timer,re;
var isIE = /msie/.test(navigator.userAgent.toLowerCase());

function init(){
	tab("l");
	tab("a");
	oPicCon = document.getElementById("show_pic");
	oUl = oPicCon.getElementsByTagName("ul")[0];
	aLi = oUl.getElementsByTagName("li");
	iLen = aLi[0].offsetWidth;
	oLeft = document.getElementById("turn_left");
	oRight = document.getElementById("turn_right");

	var oTextarea = document.getElementById("greetings");
	//alert(oTextarea.name);
	oTextarea.onfocus = function(){
		this.className = "greetings_s";
	}
	oTextarea.onblur = function(){
		this.className = (this.value == "")?"greetings_n":"greetings_s";
	}
}

function tab(str){
	var sTab = str + "_t";
	var sContent = str + "_c";
	var oUl = document.getElementById(sTab);
	var aLi = oUl.getElementsByTagName("li");
	for (var i = 0 ; i < aLi.length ; i++ ){
		aLi[i].i = i;
		aLi[i].onclick = function(){
			for (var j = 0 ; j < aLi.length ; j++ ){
				aLi[j].className = "";
				document.getElementById(sContent+j).style.display = "none";
			}
			this.className = "s";
			document.getElementById(sContent+this.i).style.display = "block";
		}
	}
}

function change(n){
	var aLi = oUl.getElementsByTagName("li");
	if(n < 0){
		oLeft.onclick = "";
		var oElement = aLi[0].cloneNode(true);
		oUl.appendChild(oElement);
		re = aLi[0].innerHTML;
		turn_right();
	}else if(n > 0){
		oRight.onclick = "";
		var oElement = aLi[aLi.length-1].cloneNode(true);
		oElement.style.marginLeft = -iLen + "px";
		oUl.insertBefore(oElement,aLi[0]);
		re = oElement.innerHTML;
		turn_left();
	}
}

function turn_left(){
	var aLi = oUl.getElementsByTagName("li");
	if((aLi[0].offsetLeft-oUl.offsetLeft) < -10&&aLi[0].innerHTML == re){
		aLi[0].style.marginLeft = (aLi[0].offsetLeft - oUl.offsetLeft +10)+"px";
		timer = setTimeout("turn_left()",100);
	}else if(aLi[0].innerHTML == re){
		oUl.removeChild(aLi[aLi.length-1]);
		oRight.onclick = function(){change(1);}
	}
}

function turn_right(){
	var aLi = oUl.getElementsByTagName("li");
	if((aLi[0].offsetLeft-oUl.offsetLeft) > -(iLen-10)&&aLi[0].innerHTML == re){
		aLi[0].style.marginLeft = (aLi[0].offsetLeft-oUl.offsetLeft-10)+"px";
		timer = setTimeout("turn_right()",100);
	}else if(aLi[0].innerHTML == re){
		oUl.removeChild(aLi[0]);
		oLeft.onclick = function(){change(-1);}	
	}
}

function show(obj){
	var oMsgMore = document.getElementById("msg_more");
	var oMsgList = document.getElementById("msg_list");
	var aDd = obj.parentNode.getElementsByTagName("dd");
	oMsgMore.style.display = "block";
	oMsgMore.innerHTML = "";
	if(isIE){
		var local = get_location(oMsgList);
		oMsgMore.style.top = local.top + "px";
		oMsgMore.style.left = local.left + "px";
	}else {
		oMsgMore.style.top = oMsgList.offsetTop + "px";
		oMsgMore.style.left = oMsgList.offsetLeft + "px";
	}
	var oSpan1 = document.createElement("span");
	oSpan1.innerHTML = aDd[1].innerHTML;
	oSpan1.className = "name";
	var oSpan2 = document.createElement("span");
	oSpan2.innerHTML = aDd[2].innerHTML;
	var oP = document.createElement("p");
	oP.innerHTML = aDd[3].innerHTML;
	var oA = document.createElement("a");
	oA.innerHTML = "[点击关闭]";
	oMsgMore.appendChild(oSpan1);
	oMsgMore.appendChild(document.createTextNode("发表于"))
	oMsgMore.appendChild(oSpan2);
	oMsgMore.appendChild(oP);
	oMsgMore.appendChild(oA);
	oA.onclick = function() {
		this.parentNode.style.display = "none";
		return false;
	}
}

function get_location(obj){
	var offsetparent = obj;
	var local = new Local(0,0);
	while(offsetparent != null && offsetparent.nodeName != "BODY"){
		 local.left += offsetparent.offsetLeft;
		 local.top += offsetparent.offsetTop;
		 offsetparent=offsetparent.parentNode;
		 //alert(offsetparent.offsetTop+"|"+offsetparent.offsetLeft+"\n"+local.top+"|"+local.left+"\n"+offsetparent.nodeName);
	}
	return local;
}

function Local(top,left){
	this.top = top;
	this.left = left;
}