/**
 * stringLength validator
 *
 * @link        http://formvalidation.io/validators/stringLength/
 * @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': {
            stringLength: {
                'default': 'Please enter a value with valid length',
                less: 'Please enter less than %s characters',
                more: 'Please enter more than %s characters',
                between: 'Please enter value between %s and %s characters long'
            }
        }
    });

    FormValidation.Validator.stringLength = {
        html5Attributes: {
            message: 'message',
            min: 'min',
            max: 'max',
            trim: 'trim',
            utf8bytes: 'utf8Bytes'
        },

        enableByHtml5: function($field) {
            var options   = {},
                maxLength = $field.attr('maxlength'),
                minLength = $field.attr('minlength');
            if (maxLength) {
                options.max = parseInt(maxLength, 10);
            }
            if (minLength) {
                options.min = parseInt(minLength, 10);
            }

            return $.isEmptyObject(options) ? false : options;
        },

        /**
         * Check if the length of element value is less or more than given number
         *
         * @param {FormValidation.Base} validator The validator plugin instance
         * @param {jQuery} $field Field element
         * @param {Object} options Consists of following keys:
         * - min
         * - max
         * At least one of two keys is required
         * The min, max keys define the number which the field value compares to. min, max can be
         *      - A number
         *      - Name of field which its value defines the number
         *      - Name of callback function that returns the number
         *      - A callback function that returns the number
         *
         * - message: The invalid message
         * - trim: Indicate the length will be calculated after trimming the value or not. It is false, by default
         * - utf8bytes: Evaluate string length in UTF-8 bytes, default to false
         * @returns {Object}
         */
        validate: function(validator, $field, options) {
            var value = validator.getFieldValue($field, 'stringLength');
            if (options.trim === true || options.trim === 'true') {
                value = $.trim(value);
            }

            if (value === '') {
                return true;
            }

            var locale     = validator.getLocale(),
                min        = $.isNumeric(options.min) ? options.min : validator.getDynamicOption($field, options.min),
                max        = $.isNumeric(options.max) ? options.max : validator.getDynamicOption($field, options.max),
                // Credit to http://stackoverflow.com/a/23329386 (@lovasoa) for UTF-8 byte length code
                utf8Length = function(str) {
                                 var s = str.length;
                                 for (var i = str.length - 1; i >= 0; i--) {
                                     var code = str.charCodeAt(i);
                                     if (code > 0x7f && code <= 0x7ff) {
                                         s++;
                                     } else if (code > 0x7ff && code <= 0xffff) {
                                         s += 2;
                                     }
                                     if (code >= 0xDC00 && code <= 0xDFFF) {
                                         i--;
                                     }
                                 }
                                 return s;
                             },
                length     = options.utf8Bytes ? utf8Length(value) : value.length,
                isValid    = true,
                message    = options.message || FormValidation.I18n[locale].stringLength['default'];

            if ((min && length < parseInt(min, 10)) || (max && length > parseInt(max, 10))) {
                isValid = false;
            }

            switch (true) {
                case (!!min && !!max):
                    message = FormValidation.Helper.format(options.message || FormValidation.I18n[locale].stringLength.between, [parseInt(min, 10), parseInt(max, 10)]);
                    break;

                case (!!min):
                    message = FormValidation.Helper.format(options.message || FormValidation.I18n[locale].stringLength.more, parseInt(min, 10));
                    break;

                case (!!max):
                    message = FormValidation.Helper.format(options.message || FormValidation.I18n[locale].stringLength.less, parseInt(max, 10));
                    break;

                default:
                    break;
            }

            return {
                valid: isValid,
                message: message
            };
        }
    };
}(jQuery));
