/**
 * Builds the URL slugs of dumps and playlists from their titles. The dump and
 * playlist services store the slug when the record is created or retitled.
 *
 * @module
 */

/**
 * Matches a UUID. A dump or playlist route takes either an id or a slug, and
 * the services test the parameter with this to know which column to look up.
 */
export const UUID_RE =
  /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i;

/**
 * Turns `title` into lowercase ASCII words joined by dashes, at most 60
 * characters long. Accents are dropped, and a title with no ASCII letter or
 * digit gives `untitled`.
 */
export function slugify(title: string): string {
  const slug = title
    .toLowerCase()
    .normalize("NFD")
    // NFD splits an accented letter into the letter and a combining mark.
    .replace(/[\u0300-\u036f]/g, "")
    .replace(/[^a-z0-9]+/g, "-")
    .replace(/^-+|-+$/g, "")
    .substring(0, 60);
  return slug || "untitled";
}

/**
 * Returns a record's slug, its title's {@link slugify} followed by the first 8
 * characters of `id`. The suffix keeps two records with the same title apart.
 */
export function makeSlug(title: string, id: string): string {
  return `${slugify(title)}-${id.substring(0, 8)}`;
}