var curPage = 0;
var index = 0;
var curFileID = 1;//maxFileID;
var articleNum = 0;

function clearDataNode()
{
	var articles = dataNode.selectNodes("article");
	var len = articles.length;
	var i = 0;
	for (i = 0; i < len; i ++)
	{
		dataNode.removeChild(articles[i]);
	}
}

function isLastPage()
{
	if (curPage >= pageTotal)
	{
		return true;
	}
	else
	{
		return false;
	}
}
function isFirstPage()
{
	if (curPage <= 1)
	{
		return true;
	}
	else
	{
		return false;
	}
}

function getCurrentFile()
{
	return fileName + curFileID + ".xml";
}

function hasNextFile()
{
	if (curFileID < maxFileID)
	{
		return true;
	}
	else
	{
		return false;
	}
}

function hasPrevFile()
{
	if (curFileID > 1)
	{
		return true;
	}
	else
	{
		return false;
	}
}

function getNextFile()
{
	curFileID ++;
	retfileName = fileName + curFileID + ".xml";
	return retfileName;
}

function getPrevFile()
{
	curFileID --;
	retfileName = fileName + curFileID + ".xml";
	return retfileName;
}

function prevPage()
{
	if (isFirstPage())
	{
		alert("已经是第一页了");
		return;
	}
	index -= (pageSize + dataNode.selectNodes("article").length);
	while (index < 0)
	{
		if (! hasPrevFile())
		{
			alert("没有稿件了");
			return;
		}
		worker.load(getPrevFile());
		var rowNodes = worker.selectNodes("data/article");
		index = rowNodes.length + index;
	}
	curPage -= 2;
	nextPage();
}

function nextPage()
{
	if (isLastPage())
	{
		alert("已经是最后一页了");
		return;
	}
	worker.load(getCurrentFile());
	var rowNodes = worker.selectNodes("data/article");
	var len = rowNodes.length;
	if (! hasNextFile())
	{
		if (index >= len)
		{
			alert("没有稿件了");
			return;
		}
	}

	curPage ++;
	clearDataNode();
	var articleNum = 0;

	for (;;)
	{
		while (index < len)
		{
			dataNode.appendChild(rowNodes[index]);
			document.getElementById("mytable").innerHTML=document.getElementById("mytable").getAttribute("tablestyle")+dataNode.text+"</table>";
			//alert(document.getElementById("mytable").innerHTML);
			index ++;
			articleNum ++;
			if (articleNum  >= pageSize)
			{
				return;
			}
		}
		if (! hasNextFile())
		{
			break;
		}
		worker.load(getNextFile());
		rowNodes = worker.selectNodes("data/article");
		len = rowNodes.length;
		index = 0;
	}
}
function doJump() 
{
	var jump = document.all("jumppage").value;
	if( jump == "") {
		alert("请指定一个页号");
		return;
	}
	if( jump > pageTotal || jump <= 0) {
		alert("指定的页号越界，请重新输入");
		return
	}
	curPage = jump - 1;
	curFileID = parseInt(curPage*pageSize/20 + 1);
	index = curPage*pageSize%20
	nextPage();
	document.all("pageSerialNum").innerText = "第" + curPage + "页";
}
function doNextPage()
{
	nextPage();
	document.all("pageSerialNum").innerText = "第" + curPage + "页";
}

function doPrevPage()
{
	prevPage();
	document.all("pageSerialNum").innerText = "第" + curPage + "页";
}

function doLastPage()
{
	while(curPage<pageTotal)
	{
		nextPage();
	}
	document.all("pageSerialNum").innerText = "第" + pageTotal + "页";
}

function doFirstPage()
{
	while(curPage>1)
	{
		prevPage();
	}
	document.all("pageSerialNum").innerText = "第" + 1 + "页";
}