module.exports = {
  isDefaultRequiredValue: function (values, value) {
    return value === undefined || value === '';
  },
  hasValue: function (values, value) {
    return !!value;
  },
  matchRegexp: function (values, value, regexp) {
    return !!value && !!value.match(regexp);
  },
  isUndefined: function (values, value) {
    return value === undefined;
  },
  isEmptyString: function (values, value) {
    return value === '';
  },
  isEmail: function (values, value) {
    return !value || value.match(/^((([a-z]|\d|[!#\$%&'\*\+\-\/=\?\^_`{\|}~]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])+(\.([a-z]|\d|[!#\$%&'\*\+\-\/=\?\^_`{\|}~]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])+)*)|((\x22)((((\x20|\x09)*(\x0d\x0a))?(\x20|\x09)+)?(([\x01-\x08\x0b\x0c\x0e-\x1f\x7f]|\x21|[\x23-\x5b]|[\x5d-\x7e]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(\\([\x01-\x09\x0b\x0c\x0d-\x7f]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]))))*(((\x20|\x09)*(\x0d\x0a))?(\x20|\x09)+)?(\x22)))@((([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))\.)+(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))$/i);
  },
  isTrue: function (values, value) {
    return value === true;
  },
  isFalse: function (values, value) {
    return value === false;
  },
  isNumeric: function (values, value) {
    if (!value) {
        return false;
    }
    if (typeof value === 'number') {
      return true;
    } else {
      var matchResults = value.match(/[-+]?(\d*[.])?\d+/);
      if (!!matchResults) {
        return matchResults[0] == value;
      } else {
        return false;
      }
    }
  },
  isAlpha: function (values, value) {
    return value && /^[a-zA-Z]+$/.test(value);
  },
  isWords: function (values, value) {
    return value && /^[a-zA-Z\s]+$/.test(value);
  },
  isSpecialWords: function (values, value) {
    return !value || value.match(/^[a-zA-Z\s\u00C0-\u017F]+$/);
  },
  isLength: function (values, value, length) {
    return value && value.length === length;
  },
  equals: function (values, value, eql) {
    return value == eql;
  },
  equalsField: function (values, value, field) {
    return value == values[field];
  },
  maxLength: function (values, value, length) {
    return value && value.length && value.length <= length;
  },
  minLength: function (values, value, length) {
    return value && value.length && value.length >= length;
  }
};