/**
 * meid validator
 *
 * @link        http://formvalidation.io/validators/meid/
 * @author      https://twitter.com/nghuuphuoc
 * @copyright   (c) 2013 - 2015 Nguyen Huu Phuoc
 * @license     http://formvalidation.io/license/
 */
(function($) {
    FormValidation.I18n = $.extend(true, FormValidation.I18n || {}, {
        'en_US': {
            meid: {
                'default': 'Please enter a valid MEID number'
            }
        }
    });

    FormValidation.Validator.meid = {
        /**
         * Validate MEID (Mobile Equipment Identifier)
         * Examples:
         * - Valid: 293608736500703710, 29360-87365-0070-3710, AF0123450ABCDE, AF-012345-0ABCDE
         * - Invalid: 2936087365007037101
         *
         * @see http://en.wikipedia.org/wiki/Mobile_equipment_identifier
         * @param {FormValidation.Base} validator The validator plugin instance
         * @param {jQuery} $field Field element
         * @param {Object} options Can consist of the following keys:
         * - message: The invalid message
         * @returns {Boolean}
         */
        validate: function(validator, $field, options) {
            var value = validator.getFieldValue($field, 'meid');
            if (value === '') {
                return true;
            }

            switch (true) {
                // 14 digit hex representation (no check digit)
                case /^[0-9A-F]{15}$/i.test(value):
                // 14 digit hex representation + dashes or spaces (no check digit)
                case /^[0-9A-F]{2}[- ][0-9A-F]{6}[- ][0-9A-F]{6}[- ][0-9A-F]$/i.test(value):
                // 18 digit decimal representation (no check digit)
                case /^\d{19}$/.test(value):
                // 18 digit decimal representation + dashes or spaces (no check digit)
                case /^\d{5}[- ]\d{5}[- ]\d{4}[- ]\d{4}[- ]\d$/.test(value):
                    // Grab the check digit
                    var cd = value.charAt(value.length - 1);

                    // Strip any non-hex chars
                    value = value.replace(/[- ]/g, '');

                    // If it's all digits, luhn base 10 is used
                    if (value.match(/^\d*$/i)) {
                        return FormValidation.Helper.luhn(value);
                    }

                    // Strip the check digit
                    value = value.slice(0, -1);

                    // Get every other char, and double it
                    var cdCalc = '';
                    for (var i = 1; i <= 13; i += 2) {
                        cdCalc += (parseInt(value.charAt(i), 16) * 2).toString(16);
                    }

                    // Get the sum of each char in the string
                    var sum = 0;
                    for (i = 0; i < cdCalc.length; i++) {
                        sum += parseInt(cdCalc.charAt(i), 16);
                    }

                    // If the last digit of the calc is 0, the check digit is 0
                    return (sum % 10 === 0)
                            ? (cd === '0')
                            // Subtract it from the next highest 10s number (64 goes to 70) and subtract the sum
                            // Double it and turn it into a hex char
                            : (cd === ((Math.floor((sum + 10) / 10) * 10 - sum) * 2).toString(16));

                // 14 digit hex representation (no check digit)
                case /^[0-9A-F]{14}$/i.test(value):
                // 14 digit hex representation + dashes or spaces (no check digit)
                case /^[0-9A-F]{2}[- ][0-9A-F]{6}[- ][0-9A-F]{6}$/i.test(value):
                // 18 digit decimal representation (no check digit)
                case /^\d{18}$/.test(value):
                // 18 digit decimal representation + dashes or spaces (no check digit)
                case /^\d{5}[- ]\d{5}[- ]\d{4}[- ]\d{4}$/.test(value):
                    return true;

                default:
                    return false;
            }
        }
    };
}(jQuery));
