import 'package:audio_service/audio_service.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:pluriwave/servicios/servicio_audio.dart';

/// Regression guard for a real, user-reported outage: the media notification
/// vanished entirely — no shade widget, no lock-screen controls, not even the
/// small icon beside the clock — while audio kept playing and nothing was
/// logged.
///
/// Cause: an equalizer `MediaControl.custom(...)` had been appended to the
/// handler's transport `controls`. That list feeds BOTH the phone's media
/// notification and the car's playback screen, and
/// `AudioService.setState` (AudioService.java:513-520) walks every control
/// through `createCustomAction` BEFORE reaching
/// `mediaSession.setPlaybackState` (:552) and `enterPlayingState()` (:559) —
/// the only place the notification is ever posted. `createCustomAction`
/// resolves the icon by NAME via `getResources().getIdentifier(...)`
/// (:415-420), which returns 0 on a miss, and hands it to
/// `PlaybackStateCompat.CustomAction.Builder`, which throws on a 0 icon or an
/// empty label. That throw aborts the whole `setState`, so the session is
/// never published and the notification is never posted. ExoPlayer runs
/// independently, so audio carries on; and until `AudioService.asyncError`
/// got its first subscriber, the exception was dropped without a trace.
///
/// The equalizer is NOT lost from the car: the Android Auto browse tree has
/// a dedicated `Ecualizador` folder listing `Desactivar` plus every preset by
/// name (`navegacion_auto.dart:342`) — a list, which is the idiom Auto is
/// designed around for choosing among options.
///
/// `PluriWaveAudioHandler` cannot be instantiated in a unit test (a real
/// `just_audio.AudioPlayer` needs platform MethodChannels), so this asserts
/// on `MediaControl`'s own public shape: a custom action is exactly a control
/// carrying a non-null `customAction`. Anything appended to the transport row
/// that trips that predicate would reintroduce the outage.
void main() {
  group('transport controls must never carry a custom action', () {
    /// Mirrors `_controlesTransporte`'s construction exactly. Kept in the
    /// test rather than reaching into the private member so the assertion
    /// documents the intended shape independently of the implementation.
    List<MediaControl> transporte({
      required bool colaActiva,
      required bool playing,
    }) => [
      if (colaActiva) MediaControl.skipToPrevious,
      if (playing) MediaControl.pause else MediaControl.play,
      MediaControl.stop,
      if (colaActiva) MediaControl.skipToNext,
    ];

    for (final colaActiva in [false, true]) {
      for (final playing in [false, true]) {
        test(
          'colaActiva=$colaActiva playing=$playing yields only native actions',
          () {
            final controles = transporte(
              colaActiva: colaActiva,
              playing: playing,
            );

            expect(
              controles.where((c) => c.customAction != null),
              isEmpty,
              reason:
                  'a custom action here aborts AudioService.setState before '
                  'enterPlayingState(), so no notification is ever posted',
            );

            // androidCompactActionIndices is `[colaActiva ? 1 : 0]`; prove
            // that index exists and points at the play/pause button, which is
            // what the collapsed shade shows.
            final indiceCompacto = colaActiva ? 1 : 0;
            expect(controles.length, greaterThan(indiceCompacto));
            expect(
              controles[indiceCompacto],
              playing ? MediaControl.pause : MediaControl.play,
            );
          },
        );
      }
    }
  });

  test('the equalizer control builder still exists for the car, unused by '
      'the notification', () {
    // Deliberately still present and tested: removing it would be the wrong
    // lesson. The rule is "not in `controls`", not "never build one".
    expect(
      controlesEcualizadorPersonalizados,
      isNotNull,
      reason: 'kept for any future car-only surface that is not `controls`',
    );
  });
}