import 'dart:async';
import 'dart:io';
import 'dart:ui' show Locale;

import 'package:flutter/foundation.dart';
import 'package:flutter/services.dart';
import 'package:url_launcher/url_launcher.dart';

import '../l10n/gen/app_localizations.dart';
import '../modelos/archivo_grabacion.dart';
import '../modelos/emisora.dart';
import '../servicios/servicio_grabacion_radio.dart';

/// Recording state extracted from `EstadoRadio` (S4-R2).
///
/// Owns [ServicioGrabacionRadio] and the recording-state subscription, and
/// notifies ONLY its own listeners — recording progress must not rebuild
/// `EstadoRadio` consumers (S4-R5). Playback orchestration (stop recording on
/// pause/stop/station switch) stays in `EstadoRadio`, which keeps a reference
/// to this notifier.
/// Whether [emisora] is something the recorder can actually capture: a live
/// network stream.
///
/// The recorder opens the URL as an HTTP stream and writes the bytes to disk,
/// so anything else fails inside the HTTP client with a message no user can
/// act on ("Unsupported scheme 'content' in URI content://...").
///
/// This is not hypothetical tidiness. `PluriWaveAudioHandler._cambiarFuente`
/// sets `emisoraActual` for EVERY source it plays, so a local MP3 shows up
/// here as an `Emisora` whose `url` is the `content://` document URI it was
/// opened from. Recording a local file makes no sense anyway — it is already
/// on the device.
bool esEmisoraGrabable(Emisora emisora) {
  final esquema = Uri.tryParse(emisora.url)?.scheme.toLowerCase();
  return esquema == 'http' || esquema == 'https';
}

class EstadoGrabacion extends ChangeNotifier {
  EstadoGrabacion({
    ServicioGrabacionRadio? servicio,
    Emisora? Function()? emisoraActual,
    void Function(String mensaje)? alError,
  }) : servicio = servicio ?? ServicioGrabacionRadio(),
       _emisoraActual = emisoraActual ?? (() => null),
       _alError = alError {
    _suscripcion = this.servicio.estadoStream.listen((estado) {
      if (estado.tipo == EstadoGrabacionRadioTipo.error &&
          estado.error != null) {
        _alError?.call(_textos.radioRecordingError(estado.error!));
      }
      notifyListeners();
    });
  }

  static const MethodChannel _fileActionsChannel = MethodChannel(
    'pluriwave/file_actions',
  );

  final ServicioGrabacionRadio servicio;

  /// Callback into the owner (EstadoRadio) for the currently playing station;
  /// keeps this notifier free of any station-list coupling.
  final Emisora? Function() _emisoraActual;

  /// User-visible error sink (EstadoRadio routes it to its snackbar stream).
  final void Function(String mensaje)? _alError;

  StreamSubscription<EstadoGrabacionRadio>? _suscripcion;
  AppLocalizations? _l10n;

  AppLocalizations get _textos {
    final actual = _l10n;
    if (actual != null) return actual;
    return lookupAppLocalizations(const Locale('es'));
  }

  void configurarLocalizaciones(AppLocalizations l10n) {
    _l10n = l10n;
    servicio.configurarLocalizaciones(l10n);
  }

  Future<void> inicializar() => servicio.inicializar();

  EstadoGrabacionRadio get estado => servicio.estado;
  bool get activa => servicio.estado.activa;
  String? get directorioConfigurado => servicio.directorioConfigurado;
  int get maxBytes => servicio.maxBytes;
  File? get ultimoArchivo => servicio.ultimoArchivo;

  Future<void> iniciar({Duration? duracion}) async {
    final actual = _emisoraActual();
    // `emisoraActual` is set by `_cambiarFuente` for EVERY source, local
    // tracks included -- a local file becomes an `Emisora` whose `url` is the
    // SAF `content://` URI it was opened from. Handing that to the recorder
    // produced "Unsupported scheme 'content' in URI content://..." on screen,
    // and it started happening only once local music playback existed: before
    // that, whatever was playing was always a real station.
    if (actual == null || !esEmisoraGrabable(actual)) {
      _alError?.call(_textos.recordingSelectStationFirst);
      return;
    }
    try {
      await servicio.iniciar(actual, duracion: duracion);
    } catch (e) {
      _alError?.call(_textos.recordingStartError(e.toString()));
    }
  }

  Future<void> detener() => servicio.detener();

  Future<void> cambiarMaxBytes(int bytes) async {
    await servicio.guardarMaxBytes(bytes);
    notifyListeners();
  }

  Future<void> cambiarDirectorio(String path) async {
    await servicio.guardarDirectorio(path);
    notifyListeners();
  }

  Future<void> restaurarDirectorio() async {
    await servicio.limpiarDirectorioConfigurado();
    notifyListeners();
  }

  Future<String> directorioEfectivo() => servicio.directorioEfectivo();

  /// WU15, recordings-library: browsable listing of recording files
  /// already on disk. Thin delegate — no additional logic.
  Future<List<ArchivoGrabacion>> listarGrabaciones() =>
      servicio.listarGrabaciones();

  /// WU15: deletes [ruta] and notifies listeners so the library screen's
  /// row disappears.
  Future<void> eliminarGrabacion(String ruta) async {
    await servicio.eliminarGrabacion(ruta);
    notifyListeners();
  }

  /// WU15: renames the recording at [ruta] to [nuevoNombre] and notifies
  /// listeners so the library screen reflects the new name.
  Future<void> renombrarGrabacion(String ruta, String nuevoNombre) async {
    await servicio.renombrarGrabacion(ruta, nuevoNombre);
    notifyListeners();
  }

  Future<bool> abrirDirectorio() async {
    final ruta = await directorioEfectivo();
    await Directory(ruta).create(recursive: true);
    if (!kIsWeb && Platform.isAndroid) {
      final abierto = await _fileActionsChannel.invokeMethod<bool>(
        'viewDirectory',
        {'path': ruta},
      );
      return abierto ?? false;
    }
    final uri = Uri.directory(ruta);
    return launchUrl(uri, mode: LaunchMode.externalApplication);
  }

  Future<bool> abrirUltimaGrabacion() async {
    final archivo = ultimoArchivo;
    if (archivo == null || !await archivo.exists()) {
      debugPrint('[PluriWave][recordings] last recording missing');
      return false;
    }
    debugPrint('[PluriWave][recordings] opening last file: ${archivo.path}');
    if (!kIsWeb && Platform.isAndroid) {
      final abierto = await _fileActionsChannel.invokeMethod<bool>('openFile', {
        'path': archivo.path,
        'mimeType': 'audio/*',
      });
      return abierto ?? false;
    }
    return launchUrl(
      Uri.file(archivo.path),
      mode: LaunchMode.externalApplication,
    );
  }

  @override
  void dispose() {
    _suscripcion?.cancel();
    unawaited(servicio.dispose());
    super.dispose();
  }
}