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/* <pre> [[User:DStoykov/defaultsort.js]] <nowiki> */

function defaultsort() {
//var apiurl = mw.config.get('wgServer')+mw.config.get('wgScriptPath')+'/api.php?action=query&meta=siteinfo&siprop=namespaces&format=xml';
//var xmlhttp = window.XMLHttpRequest ? new XMLHttpRequest() : window.ActiveXObject ? new ActiveXObject("Microsoft.XMLHTTP") : null;
//xmlhttp.open('GET',apiurl, false);
//xmlhttp.send(null);
//alert(xmlhttp.responseXML.getElementById('14').childNodes[0].nodeValue);

    var txt = document.editform.wpTextbox1.value;
    var sortkey = '';
    // Save the position of the editbox scrollbar
    var scrollPosition = document.editform.wpTextbox1.scrollTop;
    // Create an array of all category links
    if (txt.match(/\{\{\s*defaultsort/i)) {
        alert('There\'s already a defaultsort statement!');
        return;
    } 
    var catlinks = txt.match(/\[\[\s*((C|K)at(e|e)gor(y|i|ie|ia|ia|ija|io)|Кат(е|э)гор(ия|ија|ія|ыя)|Luokka|Flokkur)\s*:.*\]\]/ig);
    if (!catlinks) {
        alert('There are no category links!');
        return;
    } 
    for (i=0; i< catlinks.length; i++) {
        // Extract the name of the category
        var catname = catlinks[i].replace(/.+\s*:\s*([^|]*[^|\s])\s*(\|.*)?\]\]/,"$1");
        // Extract the sort key 
        var match = /\|[^\]]+/.exec(catlinks[i]);
        if (match == null) {
	          alert('Category '+catname+' doesn\'t include a sort key!'); 
            return;
        }
        // Strip the '|' and any trailing spaces
        var sk = match[0].replace(/\|(.+)/, "$1").replace(/(\S) +$/,"$1");
        if (i == 0) {
            sortkey = sk;
        } else {
            if (sortkey != sk) {
                alert('Not all sort keys are identical!\nThe sort key for category '+catname+' is different.');
                return;
            }
        }
    }
    // Now that we know that everything is OK, we can proceed with modifying the content of the editbox
    txt = txt.replace(catlinks[0], "{{DEFAULTSORT:"+sortkey+"}}\n"+catlinks[0]);
    for (i=0; i< catlinks.length; i++) {
        subst = catlinks[i].replace(/\|[^\]]+/,"");
        txt = txt.replace(catlinks[i], subst);
    }
    document.editform.wpTextbox1.value=txt;
    // Restore scroll position
    document.editform.wpTextbox1.scrollTop = scrollPosition;
}

$(function () {
  if(document.forms.editform) {
    mw.util.addPortletLink('p-cactions', 'javascript:defaultsort()', 'defaultsort', 'ca-defaultsort', '', '', document.getElementById('ca-purge'));
  }
});

/* </nowiki></pre> */