New sorting plugin for book chapter numbering

sorting/chapter.js

@@ -0,0 +1,50 @@
+/**
+ * Sorts a column containing chapter numbers. This can be most useful when
+ * using DataTables for a book or book reference style application. By
+ * default, five sections are supported (a.b.c.d.e) with each being upto
+ * four-digits long. Those defaults are controlled by constMaxSections and
+ * constMaxSectionDigits respectively, and can be easily changed
+ *
+ *  @name chapter
+ *  @summary Sort book chapters numerically
+ *  @author Colin Marks
+ *
+ *  @example
+ *    $('#example').dataTable( {
+ *       columnDefs: [
+ *         { type: 'chapter', targets: 0 }
+ *       ]
+ *    } );
+ */
+
+jQuery.extend(jQuery.fn.dataTableExt.oSort, {
+	'chapter-pre': function(a) {
+		function makeFiller(count) {
+			return count === 0 ? '' : Array(count + 1).join('0');
+		}
+
+		var constMaxSections = 5;
+		var constMaxSectionDigits = 4;
+
+		var filler;
+		var result = '';
+		var sections = a.split('.');
+
+		for (var i = 0; i < constMaxSections; i++) {
+			filler = i < sections.length ? constMaxSectionDigits - sections[i].length : constMaxSectionDigits;
+
+			result += filler === 0 ? '' : Array(filler + 1).join('0');
+			result += i < sections.length ? sections[i] : '';
+		}
+
+		return result;
+	},
+
+	'chapter-asc': function(a, b) {
+		return a < b ? -1 : a > b ? 1 : 0;
+	},
+
+	'chapter-desc': function(a, b) {
+		return a < b ? 1 : a > b ? -1 : 0;
+	}
+});