toUpperCase for Greek chars

toUpperCase Greek

/*global define*/
'use strict';
define(function () {
    var map = {
        'ά': 'A',
        'Ά': 'Α',
        'έ': 'Ε',
        'Έ': 'Ε',
        'ή': 'Η',
        'Ή': 'Η',
        'ί': 'Ι',
        'Ί': 'Ι',
        'ό': 'Ο',
        'Ό': 'Ο',
        'ύ': 'Υ',
        'Ύ': 'Υ',
        'ώ': 'Ω',
        'Ώ': 'Ω'
    },
    regexp = /(ά|Ά|έ|Έ|ή|Ή|ί|Ί|ό|Ό|ύ|Ύ|ώ|Ώ)/;

    function toUpperCase (string) {
        if (!regexp.test(string)) {
            return string;
        }

        var upperCase = '',
            size = string.length,
            i, letter;

        for (i = 0; i < size; i++) {
            letter = string[i];
            if (map[letter]) {
                upperCase += map[letter];
            } else {
                upperCase += letter.toUpperCase();
            }
        }

        return upperCase;
    }

    return toUpperCase;
});