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/* Ajax mass user-rollback, version [0.0.1b]
Originally from: http://en.wikipedia.org/wiki/User:Splarka/ajaxmassrollback.js

Notes:
* Oh god this is ugly code. Haha.
* This does not revert moves but thinks it does. Not sure how to skip them either. BE AWARE.
* This only goes back 7 (configurable) days by default, but should work with any number of contribs in that timeframe.

Operation:
* Gets user's contribs (query-continues until reaching the time limit).
** For each contrib that is (top) and not (new) it leaves a checkbox (and info/links).
* After selecting which to rollback via checkboxes, it iterates over these checkboxes.
** For each revid, it gets the rollback token, title, and user.
*** Upon getting the token, it attempts rollback.
**** If successful, checkbox is unchecked and next is selected (after 1 second delay).

To do:
* Delete link for pages created by user? Maybe.
* Rewrite for efficiency when generator=usercontribs becomes implemented! Oh yah.
* Markbot optional?
* Reason field?
*/

var amrNumContribs;
if(!window.amrNumDays) var amrNumDays = 7
var amrWorking = false;

if((mw.config.get('wgNamespaceNumber') == 2 || mw.config.get('wgNamespaceNumber') == 3) && mw.config.get('wgTitle').indexOf('/') == -1 && (mw.config.get('wgAction') != 'edit' || mw.config.get('wgAction') != 'submit') && true) $(function() {
  mw.util.addPortletLink('p-cactions','/wiki/Special:BlankPage?blankspecial=ajaxmr&user=' + encodeURIComponent(mw.config.get('wgTitle')),'Mass Rollback','p-mr');
});

if(mw.config.get('wgCanonicalSpecialPageName') && mw.config.get('wgCanonicalSpecialPageName') == 'Contributions' && true) $(function() {
  var ucfrm = document.getElementsByTagName('form')[0];
  var targ = '';
  if(ucfrm.target && ucfrm.target.value != '') {
    targ = '&user=' + encodeURIComponent(ucfrm.target.value);
  }
  mw.util.addPortletLink('p-cactions','/wiki/Special:BlankPage?blankspecial=ajaxmr' + targ,'Mass Rollback','p-mr');
});

if(mw.config.get('wgCanonicalSpecialPageName') && mw.config.get('wgCanonicalSpecialPageName').toLowerCase() == 'blankpage' && queryString('blankspecial') == 'ajaxmr') {
  document.title = 'Ajax Mass Rollback';
  addOnloadHook(amrForm);
  appendCSS('#amr-contriblist {border:2px solid black;margin:.7em .1em;padding:.5em;height:20em;overflow:auto;}'
  + '\n#amr-contriblist li {white-space:nowrap;} .amr-step1 {background-color:#ffff99;} .amr-step2 {background-color:#9999ff;} .amr-step3 {background-color:#99ff99;}');
}

function amrForm() {
  //subvert this Special: page to our own needs.
  var con = document.getElementById('content') || document.getElementById('mw_content');
  var bcon = document.getElementById('bodyContent') || document.getElementById('mw_contentholder');
  var fh = getElementsByClassName(con,'h1','firstHeading')[0];
  while(fh.firstChild) fh.removeChild(fh.firstChild)
  fh.appendChild(document.createTextNode('Ajax Mass Rollback'));
  for(var i=0;i<bcon.childNodes.length;i++) {
    bcur = bcon.childNodes[i];
    if(bcur.id != 'siteSub' && bcur.id != 'contentSub' && bcur.className != 'visualClear') {
      while(bcur.firstChild) bcur.removeChild(bcur.firstChild)
      if(bcur.nodeType == 3) bcur.nodeValue = '';
    }
  }

  var form = document.createElement('form');
  form.setAttribute('action','javascript:void(0)');
   var lab1 = document.createElement('label');
    lab1.setAttribute('for','amr-user')
    lab1.appendChild(document.createTextNode('User (vandal): '));
   form.appendChild(lab1);
   var inp1 = document.createElement('input');
    inp1.style.width = '20em';
    inp1.setAttribute('type','text');
    if(queryString('user')) inp1.setAttribute('value',queryString('user'));
    inp1.setAttribute('id','amr-user');
   form.appendChild(inp1);
   var sub1 = document.createElement('input');
    sub1.setAttribute('type','button');
    sub1.setAttribute('id','amr-getcontribs');
    sub1.setAttribute('value','start');
    sub1.setAttribute('onclick','amrGetContribs()');
   form.appendChild(sub1);
   var ul = document.createElement('ul');
    ul.setAttribute('id','amr-contriblist');
   form.appendChild(ul);
  bcon.appendChild(form);
  var pre = document.createElement('pre');
   pre.setAttribute('id','amr-output');
  bcon.appendChild(pre);
}

function amrGetContribs(tsoffset) {
  var start = '';
  if(tsoffset) {
    start = '&ucstart=' + tsoffset;
  } else {
    if(amrWorking) return
    amrWorking = true;
    document.getElementById('amr-user').setAttribute('disabled','disabled');
    injectSpinner(document.getElementById('amr-getcontribs'),'getcontribs-spin');
    var ul = document.getElementById('amr-contriblist');
    while(ul.firstChild) ul.removeChild(ul.firstChild)
    amrNumContribs = 0;
  }
  var user = document.getElementById('amr-user').value;
  var now = new Date();
  var stop = parseInt(now.getTime() / 1000) - 86400 * amrNumDays;
  var url = mw.config.get('wgScriptPath') + '/api.php?action=query&format=json&list=usercontribs&ucprop=flags|title|ids|comment|timestamp&uclimit=50' + start + '&ucend=' + stop + '&ucuser=' + encodeURIComponent(user);

  var req = sajax_init_object();
  req.open('GET', url, true);
  req.onreadystatechange = function() {
    if(req.readyState == 4 && req.status == 200) {
      eval("amrPopulatContribs(" + req.responseText + ",'" + req.responseText.replace(/\'/g,"`") + "')");
    }
  }
  req.send(null);
}

function amrPopulatContribs(obj,txt) {
  var ul = document.getElementById('amr-contriblist');
  if(obj['error']) {
    ul.parentNode.appendChild(document.createTextNode('Api error: ' + obj['error']['code'] + ' - ' + obj['error']['info'] + '\n'));
    return;
  }
  if(!obj['query'] || !obj['query']['usercontribs']) {
    ul.parentNode.appendChild(document.createTextNode('Unexpected response: ' + txt + '\n'));
    return;
  }
  var uc = obj['query']['usercontribs'];
  for(var i=0;i<uc.length;i++) {
    if(uc[i]['new'] == '') {
      // delete link?
    } else if(uc[i]['top'] == '') {
      var li = document.createElement('li');
       var inp = document.createElement('input');
        inp.setAttribute('type','checkbox');
        inp.setAttribute('checked','checked');
        inp.setAttribute('class','amr-cl');
        inp.setAttribute('title',uc[i].title);
        inp.setAttribute('id','amr-cl-' + uc[i].revid);
       li.appendChild(inp);
       var lab = document.createElement('label');
        lab.setAttribute('for','amr-cl-' + uc[i].revid);
        lab.appendChild(document.createTextNode(uc[i].timestamp.replace(/[TZ]/g,' ')));
       li.appendChild(lab);
       li.appendChild(document.createTextNode('('));
       addlinkchild(li, mw.config.get('wgScript') + '?curid=' + uc[i].pageid + '&diff=prev&oldid=' + uc[i].revid,'diff');
       li.appendChild(document.createTextNode(') ('));
       addlinkchild(li, mw.config.get('wgScript') + '?curid=' + uc[i].pageid + '&action=history','hist');
       li.appendChild(document.createTextNode(') . . '));
       addlinkchild(li, mw.config.get('wgScript') + '?curid=' + uc[i].pageid,uc[i].title);
       if(uc[i].comment) li.appendChild(document.createTextNode(' (' + uc[i].comment + ')'))
      ul.appendChild(li);
      amrNumContribs++;
    }
  }

  if(obj['query-continue'] && obj['query-continue']['usercontribs'] && obj['query-continue']['usercontribs']['ucstart']) {
    amrGetContribs(obj['query-continue']['usercontribs']['ucstart']);
  } else {
    amrWorking = false;
    document.getElementById('amr-user').removeAttribute('disabled');
    removeSpinner('getcontribs-spin');
    var li = document.createElement('li');
     li.appendChild(document.createTextNode(amrNumContribs + ' top contributions found for user (over last ' + amrNumDays + ' days). '));
     var sub = document.createElement('input');
      sub.setAttribute('type','button');
      sub.setAttribute('id','amr-startrollbacks');
      sub.setAttribute('value','rollback selected');
      sub.setAttribute('onclick','amrRollbackContribs()');
     li.appendChild(sub);
    ul.insertBefore(li,ul.firstChild);
  }
}

function amrRollbackContribs(automated) {
  var out = document.getElementById('amr-output');
  if(!automated) {
    if(amrWorking) return
    amrWorking = true;
    injectSpinner(document.getElementById('amr-startrollbacks'),'startrollbacks-spin');
  }

  var ul = document.getElementById('amr-contriblist');
  var ucs = getElementsByClassName(ul,'input','amr-cl');
  var uc = false;

  for(var i=0;i<ucs.length;i++) {
    if(ucs[i].checked && ucs[i].parentNode.className == '') {
      uc = ucs[i];
      break;
    }
  }

  if(!uc) {
    out.appendChild(document.createTextNode('* Done!'));
    amrWorking = false;
  } else {
    var id = uc.id.replace(/amr\-cl\-/,'');
    uc.parentNode.className = 'amr-step1';
    uc.removeAttribute('checked');
    var page = uc.title;
    out.appendChild(document.createTextNode('> Attempting to rollback [[' + page + ']]\n'));
    amrGetToken(id,page);
  }
}

function amrGetToken(id,page) {
  var out = document.getElementById('amr-output');
  out.appendChild(document.createTextNode(' > Fetching rollback token for [[' + page + ']]\n'));
  var url = mw.config.get('wgScriptPath') + '/api.php?action=query&format=json&prop=revisions&indexpageids&rvprop=user|ids&rvtoken=rollback&revids=' + id;
  var req = sajax_init_object();
  req.open('GET', url, true);
  req.onreadystatechange = function() {
    if(req.readyState == 4 && req.status == 200) {
      eval("amrRollback(" + req.responseText + ",'" + req.responseText.replace(/\'/g,"`") + "')");
    }
  }
  req.send(null);
}

function amrRollback(obj,txt) {
  var out = document.getElementById('amr-output');
  if(obj['error']) {
    out.appendChild(document.createTextNode(' ! Api error: ' + obj['error']['code'] + ' - ' + obj['error']['info'] + '\n'));
    return;
  }
  if(!obj['query'] || !obj['query']['pageids'] || !obj['query']['pages'][obj['query']['pageids'][0]]) {
    out.appendChild(document.createTextNode('  ? Unexpected response: ' + txt + '\n'));
    return;
  }
  var pid = obj['query']['pages'][obj['query']['pageids'][0]];
  if(!pid['title'] || !pid['revisions'] || !pid['revisions'][0] || !pid['revisions'][0]['user'] || !pid['revisions'][0]['revid'] || !pid['revisions'][0]['rollbacktoken']) {
    out.appendChild(document.createTextNode('  ?? Unexpected response: ' + txt + '\n'));
    return;
  }
  var id = pid['revisions'][0]['revid'];
  var uc = document.getElementById('amr-cl-' + id);
  if(uc) uc.parentNode.className = 'amr-step2'
  var user = pid['revisions'][0]['user'];
  var token = pid['revisions'][0]['rollbacktoken'];
  var title = pid['title'];
  out.appendChild(document.createTextNode('  > Token found, attempting rollback\n'));

  var params = 'action=rollback&format=json&markbot=1&token=' + encodeURIComponent(token) + '&title=' + encodeURIComponent(title) + '&user=' + encodeURIComponent(user);
  var url = mw.config.get('wgScriptPath') + '/api.php';

  var req = sajax_init_object();
  req.open('POST', url, true);
  req.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
  req.setRequestHeader('Content-length', params.length);
  req.setRequestHeader('Connection', 'close');
  req.onreadystatechange = function() {
    if(req.readyState == 4 && req.status == 200) {
      eval("amrRollbackAftermath(" + req.responseText + ",'" + req.responseText.replace(/\'/g,"`") + "')");
    }
  }
  req.send(params);
}

function amrRollbackAftermath(obj,txt) {
  var out = document.getElementById('amr-output');
  if(obj['error']) {
    out.appendChild(document.createTextNode('   ! Api error: ' + obj['error']['code'] + ' - ' + obj['error']['info'] + '\n'));
  } else if(obj['rollback'] && obj['rollback']['title']) {
    var rb = obj['rollback'];
    out.appendChild(document.createTextNode('   > Page [[' + rb['title'] + ']] rollbacked ('));
    addlinkchild(out, mw.config.get('wgScript') + '?curid=' + rb['pageid'] + '&diff=next&oldid=' + rb['old_revid'],'diff');
    out.appendChild(document.createTextNode(').\n'));
    if(obj['rollback']['old_revid']) {
      var uc = document.getElementById('amr-cl-' + obj['rollback']['old_revid']);
      uc.setAttribute('disabled','disabled');
      if(uc) uc.parentNode.className = 'amr-step3'
    }
  } else {
    out.appendChild(document.createTextNode('   ? Unexpected response: ' + txt + '\n'));
    return;
  }
  setTimeout('amrRollbackContribs(true)',1000);
}

function addlinkchild(obj,href,text,id,classes) {
  if(!obj || !href || !text) return false;
  var a = document.createElement('a');
  a.setAttribute('href',href);
  a.appendChild(document.createTextNode(text));
  if(id) a.setAttribute('id',id);
  if(classes) a.setAttribute('class',classes);
  obj.appendChild(a);
  return a;
}

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