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jQuery(document).ready(function($) {

var myContent = document.getElementsByName('wpTextbox1')[0];

if(mw.config.get('wgNamespaceNumber') != -1 && myContent) {
	mw.loader.using(['mediawiki.util']).done( function() {
	var portletlink1 = mw.util.addPortletLink('p-tb', '#', 'Infobox gap', 't-gap', 'Insert a numbering gap in an infobox', '');
	$(portletlink1).click(function(e) {
      e.preventDefault();
      wpInfoboxGap();
    });
    var portletlink2 = mw.util.addPortletLink('p-tb', '#', 'Infobox renumber', 't-ren', 'Remove numbering gaps in an infobox', '');
    $(portletlink2).click(function(e) {
      e.preventDefault();
      wpInfoboxRenumber();
    });
	});
}

// -------------------------------------------------------------------------------- //
function wpInfoboxGap()
{
 var i = 0;
 var nums = myContent.value.match(/(?:label|data|[^a-z0-9]header|class)[0-9]+(?:[a-z][ ]*=|[ ]*=)/g);
 for(i = 0; i < nums.length; i++) {
   nums[i] = nums[i].replace(/[^0-9]*([0-9]+)[^0-9]*/, '$1');
 }
 nums = nums.sort(function(a,b){return a-b});
 var firstnum = Number(nums.shift());
 var lastnum = Number(nums.pop());

 var s = Number(prompt("Gap number (between " + String(firstnum) + " and " + String(lastnum) + ")?"));
 if ( (s >= firstnum) && (s <= lastnum + 1) ) {
 	var firstgap = 0;
 	for(i = s; i < lastnum; i++) {
 		var re = new RegExp('(label|data|[^a-z0-9]header|class|rowstyle)' + String(i) + '([a-z][ ]*=|[ ]*=)', 'g');
 		if(myContent.value.search(re) < 0) {
 			if(firstgap > 0) {
	 			lastnum = i - 1;
 			}
 		} else {
 			firstgap = 1;
 		}
 	}
 	for(i = lastnum; i >= s; i--) {
 		var re = new RegExp('(label|data|[^a-z0-9]header|class|rowstyle)' + String(i) + '([a-z][ ]*=|[ ]*=)', 'g');
 		myContent.value = myContent.value.replace(re,'$1' + String(i+1) + '$2');
   }
 }
}

function wpInfoboxRenumber()
{
 var i = 0;
 var nums = myContent.value.match(/(?:label|data|[^a-z0-9]header|class|rowstyle)[0-9]+(?:[a-z][ ]*=|[ ]*=)/g);
 for(i = 0; i < nums.length; i++) {
   nums[i] = parseInt(nums[i].replace(/[^0-9]*([0-9]+)[^0-9]*/, '$1'));
 }

 var k = 1;
 var currnum  = nums[0];
 var lastnum = nums[0];
 for(i = 0; i < nums.length; i++) {
   currnum = nums[i];
   if (currnum != lastnum) {
     k = k + 1;
     lastnum = currnum;
   }
   var re = new RegExp('(label|data|[^a-z0-9]header|class|rowstyle)' + String(nums[i]) + '([a-z][ ]*=|[ ]*=)', 'g');
   myContent.value = myContent.value.replace(re,'$1 WPFOOMARK ' + String(k) + '$2');
 }
 myContent.value = myContent.value.replace(/ WPFOOMARK /g, '');
}

});