export function PostcodeDirectiveFactory() {
  return new PostcodeDirective();
}

class PostcodeDirective implements angular.IDirective {
  require = 'ngModel';
  restrict = 'A';
  link = function (scope, elm, attrs, ctrl) {
    ctrl.$validators.postcode = function (modelValue, viewValue) {
      return PostcodeRegex.test(viewValue);
    }
  }
}

const PostcodeRegex = /^[A-Z]{1,2}[0-9]{1,2}[A-Z]{0,1} ?[0-9][A-Z]{2}$/i