type FilterPattern = RegExp | RegExp[];

export interface Options {
  include?: RegExp;
  exclude?: FilterPattern;
}

export const defaultInclude =
  /\.(js)|(jsx)|(cjs)|(cjsx)|(mjs)|(mjsx)|(tsx)|(ctsx)|(mtsx)/;

export function resolveOption(options: Options = {}): Required<Options> {
  const include = options.include ?? defaultInclude;

  let exclude: FilterPattern = [/node_modules/];
  if (options.exclude) {
    exclude = exclude.concat(options.exclude);
  }

  return {
    include,
    exclude,
  };
}