import { healSort, type SortOption, type SortState } from "./columnSort";
import { compareText } from "./collate";

// Plex's sort vocabulary, source-agnostic like the feed's — a `SortOption[]` fed to the shared
// SortControl. Direction lives in the SortState (no more sibling `sortDir` on PlexFilters); the wire
// call (`plexLibrary`) still splits it into `sort` + `sort_dir` at the server boundary.

const MOVIE_SORTS = [
  "added",
  "lastwatched",
  "release",
  "year",
  "rating",
  "duration",
  "title",
] as const;
const SHOW_SORTS = ["added", "lastwatched", "release", "year", "rating", "title"] as const;

/** The sort keys a scope offers — movie libraries add `duration`; shows/both don't. */
function plexSortKeys(scope: string): string[] {
  return [...(scope === "movie" ? MOVIE_SORTS : SHOW_SORTS)];
}

/** The historical default: `sort=title`, `sort_dir=asc`. Frozen: it is handed out by reference (from
 * healSort/healPlexSort and as the provider's default state), so an accidental in-place mutation of a
 * SortState would otherwise corrupt the shared fallback for every caller. */
export const PLEX_SORT_FALLBACK: SortState = Object.freeze({ key: "title", dir: "asc" as const });

/** Labelled, alpha-ordered options for the SortControl, in the UI language's alphabet. `label`
 * resolves each key (i18n `plex.sort.<key>`). */
export function plexSortOptions(
  scope: string,
  label: (key: string) => string,
  lang: string,
): SortOption[] {
  return plexSortKeys(scope)
    .map((key) => ({ key, label: label(key) }))
    .sort((a, b) => compareText(a.label, b.label, lang));
}

/** Heal a stored sort against a scope's available keys, collapsing an out-of-scope key to the default.
 * The single heal both the sidebar control and the browse query use, so they never diverge. Always
 * non-null (the fallback is), so callers can read `.key` without a guard. */
export function healPlexSort(sort: SortState, scope: string): NonNullable<SortState> {
  return healSort(
    sort,
    plexSortKeys(scope).map((key) => ({ key, label: key })),
    PLEX_SORT_FALLBACK,
  )!;
}