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 //<pre>
//This function adds a link to the toolbox which, when clicked, displays the size of the page
//and the size of the prose in bytes. See the talk page for more details.
//
//To use this function add {{subst:js|User:Dr pda/prosesizebytes.js}} to your monobook.js
//
function loadXMLDocPassingTemplate(url,handler, page)
{
    // branch for native XMLHttpRequest object
    if (window.XMLHttpRequest) {
        var req = new XMLHttpRequest();
    }
    // branch for IE/Windows ActiveX version
    else if (window.ActiveXObject) {
        var req = new ActiveXObject("Microsoft.XMLHTTP");
   }
   if (req) {
     req.onreadystatechange = function () {handler(req, page)};
     req.open("GET", url, true);
     req.send("");
   }
}

function getWikiText(req, page) {
    // only if req shows "loaded"
    if (req.readyState == 4) {
        // only if "OK"
        if (req.status == 200) {
            // ...processing statements go here...
	 response = req.responseXML.documentElement;
         var rev = response.getElementsByTagName('rev');
	 if(rev.length > 0){
	   result = rev[0].getAttribute('size');
           result = result+'&nbsp;B';
           wiki_value = document.createElement("li");
	   wiki_value.id = "wiki-size";
	   wiki_value.innerHTML = '<b>Wiki text: </b>'+result;
	   var output = document.getElementById("document-size-stats");
	   prose_value = document.getElementById("prose-size");
	   output.insertBefore(wiki_value,prose_value);
	 }
	 else{
	  //alert("There was a problem using the Wikipedia Search to find the wiki text size\nEither the search is not working or the correct article did not appear on the first page of results");
           wiki_value = document.createElement("li");
	   wiki_value.id = "wiki-size";
	   wiki_value.innerHTML = '<b>Wiki text: </b>Problem getting wiki text size';
	   var output = document.getElementById("document-size-stats");
	   prose_value = document.getElementById("prose-size");
	   output.insertBefore(wiki_value,prose_value);
	 }
        } else {
            alert("There was a problem retrieving the XML data:\n" +
                req.statusText);
        }
    }
}

function getFileSize(req, page) {
    // only if req shows "loaded"
    if (req.readyState == 4) {
        // only if "OK"
        if (req.status == 200) {
            // ...processing statements go here...
	  var fsize = req.responseText.length;
	  window.status = fsize;
	  var total_value = document.createElement("li");
	  total_value.id = "total-size";
	  total_value.innerHTML='<b>File size: </b>'+fsize+'&nbsp;B';
	  var output = document.getElementById("document-size-stats");
	  var prose_html_value = document.getElementById("prose-size-html");
	  output.insertBefore(total_value,prose_html_value);
         } else {
            alert("There was a problem retrieving the XML data:\n" +
                req.statusText + "\n(" + url + ")");
        }
    }
}

function getLength(id){
 var textLength = 0;
 for(var i=0;i<id.childNodes.length; i++){
  if(id.childNodes[i].nodeName == '#text'){
   textLength += id.childNodes[i].nodeValue.length;
  }
  else if(id.childNodes[i].id == 'coordinates' || id.childNodes[i].className.indexOf('emplate') != -1){
    //special case for {{coord}} and {{fact}}-like templates
    //Exclude from length, and don't set background yellow
    id.childNodes[i].style.cssText = 'background-color:white';
  }
  else{
    textLength += getLength(id.childNodes[i]);
  }
 }
 return textLength;
}

function getRefMarkLength(id,html){
 var textLength = 0;
 for(var i=0;i<id.childNodes.length; i++){
  if(id.childNodes[i].className == 'reference'){
   textLength += (html)? id.childNodes[i].innerHTML.length : getLength(id.childNodes[i]);
  }
 }
 return textLength;
}

function getDocumentSize(){
 contentDivName = '';
 var skin = mw.config.get('skin');
 if(skin == 'vector' || skin == 'monobook' || skin == 'chick' || skin == 'myskin' || skin == 'simple'){
   contentDivName = 'bodyContent';
 }
 else if (skin == 'modern'){
   contentDivName = 'mw_contentholder';
 }
 else if (skin == 'standard' || skin == 'cologneblue' || skin == 'nostalgia'){
   contentDivName = 'article';
 }
 else{
   //fallback case; the above covers all currently existing skins
   contentDivName = 'bodyContent';
 }
 //Same for all skins if previewing page
 if(mw.config.get('wgAction') == 'submit') contentDivName = 'wikiPreview';
 
 var bodyContent = document.getElementById(contentDivName);
 if(document.getElementById("document-size-stats")){
   //if statistics already exist, turn them off and remove highlighting
   var output = document.getElementById("document-size-stats");
   var oldStyle = output.className;
   var pList = bodyContent.getElementsByTagName("p");
   for(var i=0;i<pList.length; i++){
     if( (pList[i].parentNode.parentNode.id == contentDivName && pList[i].parentNode.className != 'previewnote') || pList[i].parentNode.parentNode.nodeName == "BLOCKQUOTE") pList[i].style.cssText = oldStyle;
   }
   output.parentNode.removeChild(output);
   var header = document.getElementById("document-size-header");
   header.parentNode.removeChild(header);
 }
 else{
 var output = document.createElement("ul");
 output.id = "document-size-stats";

 var prose_html_value = document.createElement("li");
 prose_html_value.id = "prose-size-html";
 output.appendChild(prose_html_value);

 var ref_html_value = document.createElement("li");
 ref_html_value.id = "ref-size-html";
 output.appendChild(ref_html_value);

 var prose_value = document.createElement("li");
 prose_value.id = "prose-size";
 output.appendChild(prose_value);
 output.className = bodyContent.getElementsByTagName("p").item(0).style.cssText;

 var ref_value = document.createElement("li");
 ref_value.id = "ref-size";
 output.appendChild(ref_value);

 bodyContent.insertBefore(output, bodyContent.firstChild);

 var header = document.createElement("span");
 header.id = "document-size-header";
 header.innerHTML = '<br/>Document statistics: <small><i>(See <a href="//en.wikipedia.org/wiki/User_talk:Dr_pda/prosesize.js">here</a> for details.)<i></small>';
 bodyContent.insertBefore(header,output);

 //File size not well defined for preview mode or section edit
 if(mw.config.get('wgAction') != 'submit'){
   //If browser supports document.fileSize property (IE)
   if(document.fileSize){
     var total_value = document.createElement("li");
     total_value.id = "total-size";
     total_value.innerHTML='<b>File size: </b>'+document.fileSize+'&nbsp;B';
     output.insertBefore(total_value,prose_html_value);
   }
   else{
    loadXMLDocPassingTemplate(location.pathname,getFileSize,'')
   }
 }
 
 //Get size of images only if browser supports filesize property (IE)
 var iList = bodyContent.getElementsByTagName("img");
 if(iList.length >0 && iList[0].fileSize){
 //Get size of images included in document
   var image_size = 0;
   var first_magnify = true;

   for (var i=0;i<iList.length; i++){
    var im = iList[i];
    if(im.getAttribute("src").indexOf("magnify-clip.png") != -1){
      if(first_magnify){
        image_size += im.fileSize*1;
        first_magnify = false;
      }
    }
    else{
      image_size += im.fileSize*1;
    }
   }
   var image_value = document.createElement("li");
   image_value.id = "image-size";
   image_value.innerHTML='<b>Images: </b>'+image_size+'&nbsp;B';
   output.appendChild(image_value);

  }
 //Calculate prose size and size of reference markers ([1] etc)
 var pList = bodyContent.getElementsByTagName("p");

 prose_size = 0;
 prose_size_html = 0;
 refmark_size = 0;
 refmark_size_html = 0;
 word_count = 0;
 for(var i=0;i<pList.length; i++){
   var para = pList[i];
   if( (para.parentNode.parentNode.id == contentDivName && para.parentNode.className != 'previewnote') || para.parentNode.parentNode.nodeName == "BLOCKQUOTE"){
    prose_size += getLength(para);
    prose_size_html += para.innerHTML.length;
    refmark_size += getRefMarkLength(para,false);
    refmark_size_html += getRefMarkLength(para,true);
    word_count += para.innerHTML.replace(/(<([^>]+)>)/ig,"").split(' ').length
    para.style.cssText = "background-color:yellow";
   }
 }

 prose_value.innerHTML='<b>Prose size (text only): </b>'+(prose_size-refmark_size)+'&nbsp;B ('+word_count+' words) "readable prose size"';

 prose_html_value.innerHTML='<b>Prose size (including all HTML code): </b>'+(prose_size_html-refmark_size_html)+'&nbsp;B';


 //Calculate size of references (i.e. output of <references/>)
 var rList = bodyContent.getElementsByTagName("ol");
 var ref_size = 0;
 var ref_size_html = 0;
 for (var i=0; i<rList.length; i++){
   if(rList[i].parentNode.className == "references"){
     ref_size = getLength(rList[i]);
     ref_size_html = rList[i].innerHTML.length;
   }
 }

 ref_value.innerHTML='<b>References (text only): </b>'+(ref_size+refmark_size)+'&nbsp;B';

 ref_html_value.innerHTML='<b>References (including all HTML code): </b>'+(ref_size_html+refmark_size_html)+'&nbsp;B';

 //get correct name of article from wikipedia-defined global variables
 var pageNameUnderscores = mw.config.get('wgPageName');
 var pageNameSpaces = pageNameUnderscores.replace(/_/g,' ')

 //if page is a permalink, diff, etc don't try to search
 if(!location.pathname.match('/w/index.php')){ 
  //Get revision size from API
  var searchURL = mw.config.get('wgScriptPath') + '/api.php?action=query&prop=revisions&rvprop=size&format=xml&revids=' + mw.config.get('wgCurRevisionId');
  loadXMLDocPassingTemplate(searchURL,getWikiText,pageNameSpaces);
 }
 else if(mw.config.get('wgAction') == 'submit'){
   //Get size of text in edit box
   result = document.getElementById('wpTextbox1').value.length;
   result = result+'&nbsp;B';
   wiki_value = document.createElement("li");
   wiki_value.id = "wiki-size";
   wiki_value.innerHTML = '<b>Wiki text: </b>'+result;
   var output = document.getElementById("document-size-stats");
   prose_value = document.getElementById("prose-size");
   output.insertBefore(wiki_value,prose_value);
 }

}
}

$(function () {
  if(mw.config.get('wgAction') == 'edit' || (mw.config.get('wgAction') == 'submit' && document.getElementById('wikiDiff')) ){
    mw.util.addPortletLink('p-tb', 'javascript:alert("You need to preview the text for the prose size script to work in edit mode.")', 'Page size', 't-page-size', 'Calculate page and prose size', '', '');
    document.getElementById("t-page-size").firstChild.style.cssText = "color:black;"
  }
  else if(mw.config.get('wgAction') == 'view' || mw.config.get('wgAction') == 'submit' || mw.config.get('wgAction') == 'historysubmit' || mw.config.get('wgAction') == 'purge'){
     mw.util.addPortletLink('p-tb', 'javascript:getDocumentSize()', 'Page size', 't-page-size', 'Calculate page and prose size', '', '');
  }
});

 //</pre>