/// Local file-system node returned by the native `listAudioChildren`
/// channel call (Design "Interfaces / Contracts"): either a subfolder or an
/// audio file, one SAF tree level deep. Pure DTO — no behavior, so no unit
/// tests are warranted for it on its own (exercised indirectly through its
/// consumers, e.g. `ConstructorArbolAuto.itemsLocales`).
class NodoLocal {
  const NodoLocal({
    required this.documentId,
    required this.nombre,
    required this.esDirectorio,
  });

  /// Opaque SAF document id, unique within the picked tree. May itself
  /// contain `:`/`/` (Design "Prefix stripped by length"), so callers must
  /// never split/parse it — only wrap it verbatim in a media id.
  final String documentId;

  /// Raw on-device filename (or folder name), NOT yet title-stripped.
  final String nombre;

  /// Whether this node is a browsable subfolder (`true`) or a playable
  /// audio file (`false`).
  final bool esDirectorio;
}

/// Minimal playable local track (Design "Phase 1 minimal shape" — no
/// artist/album/duration metadata per spec's "Not in this delta"). Pure
/// DTO — no behavior, so no unit tests are warranted for it on its own.
class PistaLocal {
  const PistaLocal({
    required this.documentId,
    required this.titulo,
    required this.contentUri,
  });

  /// Opaque SAF document id for this track.
  final String documentId;

  /// Display title, already computed by the caller (filename minus
  /// extension, or a derived fallback — see `navegacion_auto.dart`).
  final String titulo;

  /// Playable `content://` URI resolved via
  /// `FuenteMusicaLocalAuto.uriContenidoDePista`.
  final String contentUri;
}