/**
 * Sorting in Javascript can be difficult to get right with non-Roman
 * characters - for which special consideration must be made. This plug-in
 * performs correct sorting on Persian characters.
 *
 *  @name Persian
 *  @summary Sort Persian strings alphabetically
 *  @author [Afshin Mehrabani](http://www.afshinblog.com/)
 *  @author [Mohammad Javad Naderi](https://github.com/mjnaderi)
 *
 *  @example
 *    $('#example').dataTable( {
 *       columnDefs: [
 *         { type: 'pstring', targets: 0 }
 *       ]
 *    } );
 */

(function () {

    var persianSort = ['آ', 'ا', 'ب', 'پ', 'ت', 'ث', 'ج', 'چ', 'ح', 'خ', 'د', 'ذ', 'ر', 'ز', 'ژ',
        'س', 'ش', 'ص', 'ط', 'ظ', 'ع', 'غ', 'ف', 'ق', 'ک', 'گ', 'ل', 'م', 'ن', 'و', 'ه', 'ی', 'ي'];

    function GetUniCode(source) {
        source = $.trim(source);
        var result = '';
        var i, index;
        for (i = 0; i < source.length; i++) {
            //Check and fix IE indexOf bug
            if (!Array.indexOf)
                index = jQuery.inArray(source.charAt(i), persianSort);
            else
                index = persianSort.indexOf(source.charAt(i));

            if (index < 0)
                index = source.charCodeAt(i) + 40;

            if (index < 10)
                index = '00' + index;
            else if (index < 100)
                index = '0' + index;

            result += index;
        }
        return 'a' + result;
    }

    jQuery.extend(jQuery.fn.dataTableExt.oSort, {
        "pstring-pre": function (a) {
            return GetUniCode($(a.toLowerCase()).text());
        },

        "pstring-asc": function (a, b) {
            return ((a < b) ? -1 : ((a > b) ? 1 : 0));
        },

        "pstring-desc": function (a, b) {
            return ((a < b) ? 1 : ((a > b) ? -1 : 0));
        }
    });

}());