/**
 * 简化分页读取内容管理RSS信息的一系列方法
 */

/**
 * 读取远程RSS信息，并嵌入到div_rss对象中
 * clientRender - 是否使用客户端合成XML+XSLT，可以在客户端完成可以减轻服务器负担，但是兼容性差
 */
function RSSImp_publish_loadPage(div_rss, clientRender){
  if(!div_rss)return;
  
  var rss_url = div_rss.rss_url;
  var rss_xsl_url = div_rss.rss_xsl_url;
  var itemFrom = div_rss.itemFrom;
  var itemCount = div_rss.itemCount;
  
  if(!itemFrom || isNaN(itemFrom) || itemFrom < 0){
    itemFrom = 0;
  }
  if(!itemCount || isNaN(itemCount) || itemCount < 0){
    itemCount = DEFAULT_ITEM_COUNT;
  }
  
  if(!rss_url || !rss_xsl_url){
    setInnerHTML(div_rss, MSG_NO_XML_XSL_URL);
  }
  
  if(itemCount)rss_url = setUrlParameter(rss_url, "itemCount", itemCount);
  if(itemFrom)rss_url = setUrlParameter(rss_url, "itemFrom", itemFrom);
  
  setInnerHTML(div_rss, MSG_XMLHTTP_LOADING);
  
  //是否由客户端渲染
  if(clientRender && document.location.toString().indexOf("gate/big5") < 0){
    //判断是不是同一个域，如果不是同一个域就使用代理
    if(rss_url.toLowerCase().indexOf("http://") >= 0 && !isSameDomain(document.location.toString(), rss_url, "http")){
      rss_url = setUrlParameter(APP_PROXY, "url", rss_url);
      rss_url = setUrlParameter(rss_url, "charset", "UTF-8");
    }
    fillRSS(rss_url, rss_xsl_url, div_rss.id);
  } else {
    var url = APP_PROXY_RSS;
    url = setUrlParameter(url, "charset", "UTF-8");
    url = setUrlParameter(url, "xml", rss_url);
    url = setUrlParameter(url, "xsl", rss_xsl_url);
    fillHTML(url, div_rss.id);
  }
}

function RSSImp_publish_pageUp(div_rss, clientRender){
  if(!div_rss)return;
  div_rss.itemFrom -= div_rss.itemCount;
  RSSImp_publish_loadPage(div_rss, clientRender);
}

function RSSImp_publish_pageDown(div_rss, clientRender){
  if(!div_rss)return;
  div_rss.itemFrom += div_rss.itemCount;
  RSSImp_publish_loadPage(div_rss, clientRender);
}