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/* 
See [[User:Alex 21/script-categoriessort.js]], original script by [[User:Alex 21]]

The main script page is [[User:Epicgenius/sortcategories.js]].
*/
mw.loader.using("mediawiki.util", function () {
	// Only run script if user is editing an article
	if (!document.forms.editform || (mw.config.get("wgAction") !== "edit" && mw.config.get("wgAction") !== "submit")) {
		return;
	}
	$(function($) {
		/*
		if (
				config.mw.wgNamespaceNumber == 1 || //talk page
				config.mw.wgArticleId === 0 || // Page doesn't exist
		) {
			return;
		} else (
		)
		*/
		mw.loader.using( ['mediawiki.util'] ).then( function () {
			var portletlink = mw.util.addPortletLink('p-tb', '#', 'Sort categories');
			$(portletlink).click( function(e) {
				e.preventDefault();
	
					// Get textbox value
					var wpTextbox1 = document.getElementById('wpTextbox1');
					var wpTextbox1_V = wpTextbox1.value;
					
					// Categories to check
					var category = "[[Category:";
					var categoryA = category+"A ";
					var categoryAn = category+"An ";
					var categoryThe = category+"The ";
					var categoryEnd = "]]"; // This might match to both categories and links
					var categoryEponymous = category+mw.config.get("wgTitle");
					var defaultSort = "{{DEFAULTSORT:";
					var stubTag = "-stub}}";
					var someTemplateEnd = "}}";
					
					// Get the text up to the start of the categories, and then all of the text with the categories.
					var categoriesStart = wpTextbox1_V.indexOf(category);
					var categoriesEnd = wpTextbox1_V.lastIndexOf(categoryEnd);
					var textBeforeCategories = wpTextbox1_V.substr(0, categoriesStart).trim();
					var textWithCategories = wpTextbox1_V.substr(categoriesStart,categoriesEnd-categoriesStart+2).trim();
					var textAfterCategories = wpTextbox1_V.substr(categoriesEnd+2).trim();
					
					// Categories should be on new lines, so split by new line, sort alphabetically with a few checks, then join again with new lines.
					// Checks: eponymous categories are listed first; categories are sorted without preceding "The"
					var splitCategories = textWithCategories.split("\n");
					splitCategories.sort(function(a, b) {
						
						if (a.substr(0, categoryEponymous.length) == categoryEponymous) return -1e8;
						if (b.substr(0, categoryEponymous.length) == categoryEponymous) return 1e8;
						
						if (a.substr(0, categoryThe.length) == categoryThe) a = a.replace(categoryThe, category);
						if (b.substr(0, categoryThe.length) == categoryThe) b = b.replace(categoryThe, category);
						
						if (a.substr(0, categoryA.length) == categoryA) a = a.replace(categoryA, category);
						if (b.substr(0, categoryA.length) == categoryA) b = b.replace(categoryA, category);
						
						if (a.substr(0, categoryAn.length) == categoryAn) a = a.replace(categoryAn, category);
						if (b.substr(0, categoryAn.length) == categoryAn) b = b.replace(categoryAn, category);
						
						return a.localeCompare(b);
					});
					
					textWithCategories = splitCategories.join("\n");
					
					if (wpTextbox1_V.indexOf(defaultSort) < 0) {
						textWithCategories = "\n"+textWithCategories;
					} else {
						textWithCategories = textWithCategories;
					}
					
					if (wpTextbox1_V.indexOf(stubTag) < 0) {
						textWithCategories = textWithCategories;
					} else {
						textWithCategories = textWithCategories+"\n\n\n";
					}
					
					// Merge pre-category text back with the sorted and joined category text, place back in textbok and add summary.
					wpTextbox1.value = textBeforeCategories+"\n"+textWithCategories+textAfterCategories;
					
					setoptions(minor = 'true');
					setreason('sorted categories alphabetically via [[User:Epicgenius/sortcategories|script]]', 'append');
					doaction('diff');
				
			});
		});
	});
});