/**
 * @type {L} The type of the locations to crawl, e.g. `URL` or `string` that represents a path.
 * @type {R} The type of the response at the location that is crawler, e.g. Cheerio object, file system `fs.Stats`.
 * @type {P} The intermediate parsed result that can be parsed from the response and generated by the crawler.
 */
interface Options<L, R, P> {
  /**
   * This function should return the response for the given location.
   */
  requester(location: L): ValueOrPromise<R | undefined>;
  /**
   * This function should return true if the crawler should parse the response, or false if not.
   */
  shouldParse(props: PreParseProps<L, R>): ValueOrPromise<boolean>;
  /**
   * This function should parse the response and convert the response to the parsed type.
   */
  parser(props: PreParseProps<L, R>): ValueOrPromise<P | undefined>;
  /**
   * This function should return true if the crawler should yield the parsed result, or false if not.
   */
  shouldYield(props: PostParseProps<L, R, P>): ValueOrPromise<boolean>;
  /**
   * This function should yield all the locations to follow in the given parsed result.
   */
  follower(props: PostParseProps<L, R, P>): AsyncGenerator<L>;
  /**
   * This function should return true if the crawler should queue the location for crawling, or false if not.
   */
  shouldQueue(props: { location: L; origin: L; response: R; parsed: P }): ValueOrPromise<boolean>;
  /**
   * The logger can be set to `console` to output debug information to the `console`.
   *
   * @default undefined
   */
  logger?: Logger;
}

interface PreParseProps<L, R> {
  location: L;
  response: R;
}

interface PostParseProps<L, R, P> extends PreParseProps<L, R> {
  parsed: P;
}

type ValueOrPromise<T> = T | Promise<T>;