import 'package:flutter/material.dart';

import '../../l10n/gen/app_localizations.dart';
import '../../servicios/musica_local_auto.dart';
import '../../servicios/servicio_audio.dart' show invalidarArbolAuto;
import '../../widgets/pluri_glass_surface.dart';
import '../../widgets/pluri_layout.dart';
import '../../widgets/pluri_push_scaffold.dart';

/// GRABACIONES Y MÚSICA group · "Música local" (design ADR-3). Body moved
/// verbatim from the former `_SeccionMusicaLocal` in `pantalla_ajustes.dart`
/// — only the panel header's icon and title were removed (the pushed
/// screen's title now carries them). Deliberately does NOT use
/// `FilePicker.platform` (see tasks.md "Grounding corrections") —
/// [FuenteMusicaLocalAutoImpl.elegirCarpeta] calls the native
/// `pickMusicFolder` channel method directly, since it needs a
/// persistable-grant SAF tree URI, not a plain filesystem path.
class PantallaAjustesMusicaLocal extends StatelessWidget {
  const PantallaAjustesMusicaLocal({super.key});

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context);
    return PluriPushScaffold(
      title: l10n.localMusicSectionTitle,
      body: ListView(
        padding: PluriLayout.pageContentPadding,
        children: const [_CuerpoMusicaLocal()],
      ),
    );
  }
}

class _CuerpoMusicaLocal extends StatefulWidget {
  const _CuerpoMusicaLocal();

  @override
  State<_CuerpoMusicaLocal> createState() => _CuerpoMusicaLocalState();
}

class _CuerpoMusicaLocalState extends State<_CuerpoMusicaLocal> {
  final _fuente = FuenteMusicaLocalAutoImpl();
  late Future<String?> _carpetaActual;

  @override
  void initState() {
    super.initState();
    _carpetaActual = _fuente.carpetaActual();
  }

  Future<void> _elegirCarpeta(BuildContext context) async {
    final messenger = ScaffoldMessenger.of(context);
    final l10n = AppLocalizations.of(context);
    try {
      final uri = await _fuente.elegirCarpeta();
      if (uri == null) return; // Cancelled — no snackbar, matches the SAF
      // picker's own "nothing changed" affordance.

      // fix/android-auto-musica-local, item 4: acaba de aparecer música
      // local donde antes no había. Android Auto cachea la raíz y no
      // vuelve a preguntar por su cuenta, así que sin esto el coche seguía
      // sin ofrecer «Música Local» hasta el siguiente re-bind — que puede
      // no llegar en toda la sesión. Fuera del `context.mounted` de abajo:
      // el árbol del coche no depende de que esta pantalla siga viva.
      invalidarArbolAuto();

      if (!context.mounted) return;
      setState(() {
        _carpetaActual = Future.value(uri);
      });
      messenger.showSnackBar(
        SnackBar(content: Text(l10n.localMusicFolderUpdated)),
      );
    } catch (e) {
      if (!context.mounted) return;
      messenger.showSnackBar(
        SnackBar(content: Text(l10n.localMusicFolderSaveError(e.toString()))),
      );
    }
  }

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context);

    return PluriGlassSurface(
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          const SizedBox(height: 8),
          Text(
            l10n.localMusicSectionDescription,
            style: Theme.of(context).textTheme.bodySmall,
          ),
          FutureBuilder<String?>(
            future: _carpetaActual,
            builder: (ctx, snap) {
              final carpeta = snap.data;
              return ListTile(
                contentPadding: EdgeInsets.zero,
                leading: const Icon(Icons.folder_outlined),
                title: Text(l10n.localMusicFolderTitle),
                subtitle: Text(
                  (carpeta == null || carpeta.isEmpty)
                      ? l10n.localMusicFolderNotConfigured
                      : nombreCarpetaDesdeUri(
                        carpeta,
                        nombreGenerico: l10n.localMusicFolderGenericName,
                      ),
                  maxLines: 2,
                  overflow: TextOverflow.ellipsis,
                ),
              );
            },
          ),
          const SizedBox(height: 8),
          FutureBuilder<String?>(
            future: _carpetaActual,
            builder: (ctx, snap) {
              final configurada = (snap.data ?? '').isNotEmpty;
              return Align(
                alignment: Alignment.centerLeft,
                child: OutlinedButton.icon(
                  icon: const Icon(Icons.folder_open_rounded),
                  label: Text(
                    configurada
                        ? l10n.localMusicChangePath
                        : l10n.localMusicChoosePath,
                  ),
                  onPressed: () => _elegirCarpeta(context),
                ),
              );
            },
          ),
        ],
      ),
    );
  }
}