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/* Disambiguation lookup script, version [0.2.8]
Originally from: http://en.wikipedia.org/wiki/User:Splarka/dabfinder.js

Notes:
* Uses the API using head/appendchild(script) and callback to avoid ajax.
* Alt command finds and hilights redirects with simple CSS append (class="mw-redirect").
* Per http://svn.wikimedia.org/viewvc/mediawiki?view=rev&revision=37270 we are limited to 500 subtemplates
** The query-continue seems to work fine even as a generator. Built a re-query system to do this automatically.

Operation:
* Adds portlet button (or works with URI parameter &finddab=true)
** Makes call to MediaWiki:Disambiguationspage links, generates array of these.
*** Makes call to generator=links / prop=templates on page title.
**** Builds array of registered links that link to disambiguation pages (that contain a disambiguation template).
***** Iterates over all <a> link objects on page, matching any that link to disambiguation, and applies green border.
***** .dablink descendant links are given a dashed border, all other found links are given a solid border.
*** Repeats call with tlcontinue if more than 500 templates have been returned in previous query.

This is a bit messy but at the time was the easiest and most thorough way to do it I could think of.
Of course, a bot might be much more efficient, but this is handy for quick on-the-fly live checking.

To do:
* test it
* centralized link list in contentSub?
* test unicode support
*/
/* Note by Meteor sandwich yum
Wishing to uphold the public domain/CC-0 license that Splarka released this under,

I hereby release my contributions to this script into the public domain. In other places, this may not be possible, so:
I hereby release my contributions to this script without any copyright whatsoever, to be used by anyone for any purpose.

Please be aware that other contributors might not do the same, so if you want to use my contributions under free use terms,
please check the Multi-licensing guide at https://en.wikipedia.org/wiki/Wikipedia:Multi-licensing.
*/

var dabnames = new Array();
var dabfound = 0;
if(mw.config.get('wgNamespaceNumber') != -1) $(findDABsButton)
function findDABsButton() {
  if(!queryString('oldid') && !queryString('diff') && (mw.config.get('wgAction') == 'view' || mw.config.get('wgAction') == 'purge')) {
    mw.util.addPortletLink('p-tb','javascript:findDABs()','Find disambiguations','t-dab');
    if(queryString('finddab')=='true') findDABs();
  }
  mw.util.addPortletLink('p-tb','javascript:findRDRs()','Find redirects','t-rdr');
  if(queryString('findrdr')=='true') findRDRs();
}

var already_written = false;
function findRDRs() {
  if (!already_written) {
    appendCSS('.mw-redirect {background-color: #ffff00;}\n#t-rdr {background-color:#ffff00;}');
    document.getElementById('t-rdr').appendChild(document.createTextNode('\nRedirects hilighted, but don\'t '));

    var a = document.createElement('a');
    a.setAttribute('href','//en.wikipedia.org/wiki/Wikipedia:Redirect#Do_not_.22fix.22_links_to_redirects_that_are_not_broken');
    a.appendChild(document.createTextNode('fix them.'));
    document.getElementById('t-rdr').appendChild(a);
    already_written = true;
  }
}

function findDABs() {
  var dab = document.getElementById('t-dab');
  if(dab) injectSpinner(dab,'dab');
  var url = mw.config.get('wgScriptPath') + '/api.php?maxage=86400&smaxage=86400&action=query&prop=links&pllimit=500&tlnamespace=10&indexpageids&format=json&rawcontinue=&callback=findDABsCB&titles=MediaWiki:Disambiguationspage';
  mw.loader.load(url);
}

function findDABsCB(obj) {
  if(!obj['query'] || !obj['query']['pages'] || !obj['query']['pageids']) return
  var links = obj['query']['pages'][obj['query']['pageids'][0]]['links']
  if(!links) return
  for(var i=0;i<links.length;i++) {
    dabnames.push(links[i]['title']);
  }
  findDABsQuery();
}

function findDABsQuery(qcont) {
  var url = mw.config.get('wgScriptPath') + '/api.php?maxage=300&smaxage=300&action=query&redirects&generator=links&gpllimit=500&prop=templates&tllimit=500&indexpageids&format=json&rawcontinue&callback=findDABlinksCB&titles=' + encodeURIComponent(mw.config.get('wgPageName'));
  if(qcont) url += '&tlcontinue=' + encodeURIComponent(qcont)
  mw.loader.load(url);
}

function findDABlinksCB(obj) {
  var dablinks = new Array();
  if(!obj['query'] || !obj['query']['pages'] || !obj['query']['pageids']) return
  appendCSS('.dablink-found {border: 2px solid #00ff00}\n .dablink .dablink-found {border:2px dashed #00ff00}');

  var ids = obj['query']['pageids'];
  var links = new Array()
  for(var i=0;i<ids.length;i++) {
    var templates = obj['query']['pages'][ids[i]]['templates'];
    if(!templates) continue
    for(var j=0;j<templates.length;j++) {
      var tpl = templates[j]['title'];
      for(var k=0;k<dabnames.length;k++) {
        if(tpl == dabnames[k]) {
          dablinks.push(obj['query']['pages'][ids[i]]['title']);
          continue;
        }
      }
    }
  }
  if(obj['query']['redirects']) {
    var dablen = dablinks.length;   //don't iterate over additions.
    var redirects = obj['query']['redirects'];
    if(redirects) {
      for(var i=0;i<redirects.length;i++) {
        for(var j=0;j<dablen;j++) {
          if(obj['query']['redirects'][i]['to'] == dablinks[j]) {
            dablinks.push(obj['query']['redirects'][i]['from']);
            continue;
          }
        }
      }
    }
  }
  var docobj = document.getElementById('bodyContent') || document.getElementById('content') || document.body;
  var links = docobj.getElementsByTagName('a')
  for(var i=0;i<links.length;i++) {
    for(var j=0;j<dablinks.length;j++) {
      //to match API: "Foo (bar)" with href: "/wiki/Foo_%28bar%29", have to do some hacky string manipulation
      //should now work with parenthesis, unicode?
      var dablink = dablinks[j].replace(/ /g,'_');
      var chklink = (links[i].hasAttribute('href')) ? links[i].getAttribute('href', 2).replace(/\#.*/,'') : ''
      chklink = chklink.replace(mw.config.get('wgArticlePath').replace(/\$1/,''),'');
      chklink = decodeURIComponent(chklink);
      if(chklink == dablink && links[i].className.indexOf('dablink-found') == -1) {
        links[i].className += ' dablink-found';
        dabfound++;
      }
    }
  }

  var dab = document.getElementById('t-dab');
  if(obj['query-continue'] && obj['query-continue']['templates']) {
    if(dab) {
      dab.appendChild(document.createElement('br'));
      dab.appendChild(document.createTextNode('more...'));
    }
    findDABsQuery(obj['query-continue']['templates']['tlcontinue']);
  } else {
    if(dab) {
      removeSpinner('dab');
      dab.appendChild(document.createElement('br'));
      if(dabfound > 0) {
        var span = document.createElement('span');
        span.appendChild(document.createTextNode(dabfound + ' links to disambiguation pages found.'));
        span.className = 'dablink-found';
        dab.appendChild(span);
      } else {
        dab.appendChild(document.createTextNode('No disambiguation links found.'));
      }
    } else {
      alert(dabfound + ' links to disambiguation pages found.');
    }
  }
}

function queryString(p) {
  var re = RegExp('[&?]' + p + '=([^&]*)');
  var matches;
  if (matches = re.exec(document.location)) {
    try {
      return decodeURI(matches[1]);
    } catch (e) {
    }
  }
  return null;
}