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/* Disambiguation lookup script, version [0.2.8]
Originally from: https://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
*/

var dabnames = [];
var dabfound = 0;
if(mw.config.get('wgNamespaceNumber') !== -1) {
	$.when( $.ready, mw.loader.using('mediawiki.util') ).then(findDABsButton);
}
function findDABsButton() {
  var el;
  var action = mw.config.get('wgAction');
  if(!mw.util.getParamValue('oldid') && !mw.util.getParamValue('diff') && (action === 'view' || action === 'purge')) {
    el = mw.util.addPortletLink('p-tb','','Find disambiguations','t-dab');
    $(el).on('click', findDABs );
    if(mw.util.getParamValue('finddab')==='true') {
    	findDABs();
    }
  }
  el = mw.util.addPortletLink('p-tb','','Find redirects','t-rdr');
  $(el).on( 'click', findRDRs );
  if(mw.util.getParamValue('findrdr')==='true') {
  	findRDRs();
  }
}

function findRDRs(event) {
  event.preventDefault();
  mw.util.addCSS('.mw-redirect {background-color: #ffff00;}\n#t-rdr {background-color:#ffff00;}');
  document.getElementById('t-rdr').appendChild(document.createTextNode('\nRedirects highlighted, but don\'t '));

  if(mw.config.get('wgServer') != 'https://en.wikipedia.org' && mw.config.get('wgScriptPath') != '/wikipedia/en/w') { return; //en.wp policy
  }
  var a = document.createElement('a');
  a.setAttribute('href','https://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);
}

function findDABs(event) {
  event.preventDefault();
  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&indexpageids&format=json&rawcontinue=&callback=findDABsCB&titles=MediaWiki:Disambiguationspage';
  $.getScript(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);
  $.getScript(url);
}

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

  var ids = obj['query']['pageids'];
  var links = [];
  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.');
    }
  }
}