/**
 * This class defines a series of static methods that are used on a
 * {@link Ext.data.Field} for performing sorting. The methods cast the
 * underlying values into a data type that is appropriate for sorting on
 * that particular field.  If a {@link Ext.data.Field#type} is specified,
 * the sortType will be set to a sane default if the sortType is not
 * explicitly defined on the field. The sortType will make any necessary
 * modifications to the value and return it.
 *
 *  - **`asText`** - Removes any tags and converts the value to a string
 *  - **`asUCText`** - Removes any tags and converts the value to an uppercase string
 *  - **`asUCString`** - Converts the value to an uppercase string
 *  - **`asDate`** - Converts the value into Unix epoch time
 *  - **`asFloat`** - Converts the value to a floating point number
 *  - **`asInt`** - Converts the value to an integer number
 *
 * It is also possible to create a custom sortType that can be used throughout
 * an application.
 *
 *      Ext.apply(Ext.data.SortTypes, {
 *          asPerson: function(person){
 *              // expects an object with a first and last name property
 *              return person.lastName.toUpperCase() + person.firstName.toLowerCase();
 *          }
 *      });
 *
 *      Ext.define('Employee', {
 *          extend: 'Ext.data.Model',
 *          fields: [{
 *              name: 'person',
 *              sortType: 'asPerson'
 *          }, {
 *              name: 'salary',
 *              type: 'float' // sortType set to asFloat
 *          }]
 *      });
 *
 * @singleton
 */
Ext.define('Ext.data.SortTypes', function() {
    var me;

    return {
        singleton: true,

        constructor: function() {
            me = this;
        },

        /**
         * Default sort that does nothing
         * @param {Object} s The value being converted
         * @return {Object} The comparison value
         */
        none: Ext.identityFn,

        /**
         * The regular expression used to strip commas
         * @type {RegExp}
         * @property
         */
        stripCommasRe: /,/g,

        /**
         * The regular expression used to strip tags
         * @type {RegExp}
         * @property
         */
        stripTagsRE: /<\/?[^>]+>/gi,

        /**
         * Strips all HTML tags to sort on text only
         * @param {Object} s The value being converted
         * @return {String} The comparison value
         */
        asText: function(s) {
            // If allowNull, return the Unicode null character.
            return (s != null) ? String(s).replace(me.stripTagsRE, '') : '\u0000';
        },

        /**
         * Strips all HTML tags to sort on text only - Case insensitive
         * @param {Object} s The value being converted
         * @return {String} The comparison value
         */
        asUCText: function(s) {
            // If allowNull, return the Unicode null character.
            /* eslint-disable-next-line newline-per-chained-call */
            return (s != null) ? String(s).toUpperCase().replace(me.stripTagsRE, '') : '\u0000';
        },

        /**
         * Case insensitive string
         * @param {Object} s The value being converted
         * @return {String} The comparison value
         */
        asUCString: function(s) {
            // If allowNull, return the Unicode null character.
            return (s != null) ? String(s).toUpperCase() : '\u0000';
        },

        /**
         * Date sorting
         * @param {Object} s The value being converted
         * @return {Number} The comparison value
         */
        asDate: function(s) {
            if (!s) {
                return 0;
            }

            if (Ext.isDate(s)) {
                return s.getTime();
            }

            return Date.parse(String(s));
        },

        /**
         * Float sorting
         * @param {Object} s The value being converted
         * @return {Number} The comparison value
         */
        asFloat: function(s) {
            var val = parseFloat(String(s).replace(me.stripCommasRe, ''));

            return isNaN(val) ? 0 : val;
        },

        /**
         * Integer sorting
         * @param {Object} s The value being converted
         * @return {Number} The comparison value
         */
        asInt: function(s) {
            var val = parseInt(String(s).replace(me.stripCommasRe, ''), 10);

            return isNaN(val) ? 0 : val;
        }
    };
});