import 'package:flutter/material.dart';
import 'package:provider/provider.dart';

import '../../estado/estado_visualizador.dart';
import '../../l10n/gen/app_localizations.dart';
import '../../widgets/pluri_glass_surface.dart';
import '../../widgets/pluri_layout.dart';
import '../../widgets/pluri_push_scaffold.dart';

/// AUDIO group · "Onda real del audio" — the point-of-intent opt-in for the
/// waveform visualizer's microphone permission.
///
/// Before this screen existed, `RECORD_AUDIO` was requested the moment
/// `VisualizadorAudio` subscribed to its native EventChannel, which the home
/// screen's "Escuchar" hero does on the user's FIRST play. A radio app that
/// pops "allow PluriWave to record audio?" the first time you press play is
/// asking for a sensitive permission with zero context, and Play expects
/// context.
///
/// Mirrors `PantallaAjustesSalidaAudio`'s point-of-intent shape (its
/// BLUETOOTH_CONNECT request sits behind the multi-device toggle the same
/// way), with one addition: the explanation is shown and accepted BEFORE the
/// flag flips, since flipping it is what triggers the system dialog.
class PantallaAjustesVisualizador extends StatelessWidget {
  const PantallaAjustesVisualizador({super.key});

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

class _CuerpoVisualizador extends StatelessWidget {
  const _CuerpoVisualizador();

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context);
    final estado = context.watch<EstadoVisualizador>();
    final habilitada = estado.ondaRealHabilitada;

    return PluriGlassSurface(
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          // GestureDetector + custom row instead of SwitchListTile, for the
          // same reason PantallaAjustesSalidaAudio does it: ListTile ink
          // inside PluriGlassSurface's DecoratedBox trips a Material
          // assertion.
          Padding(
            padding: const EdgeInsets.symmetric(vertical: 8),
            child: Row(
              children: [
                Expanded(
                  child: GestureDetector(
                    behavior: HitTestBehavior.translucent,
                    onTap: () => _alternar(context, estado, !habilitada),
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.start,
                      children: [
                        Text(
                          l10n.visualizerRealWaveTitle,
                          style: Theme.of(context).textTheme.bodyLarge,
                        ),
                        const SizedBox(height: 2),
                        Text(
                          l10n.visualizerRealWaveSubtitle,
                          style: Theme.of(context).textTheme.bodySmall,
                        ),
                      ],
                    ),
                  ),
                ),
                Switch.adaptive(
                  value: habilitada,
                  onChanged: (valor) => _alternar(context, estado, valor),
                ),
              ],
            ),
          ),
          const SizedBox(height: 8),
          // The same text the confirmation dialog shows, kept permanently on
          // screen: a user who already granted the permission should be able
          // to re-read what it is for without toggling anything.
          Text(
            l10n.visualizerRealWavePermissionExplanation,
            style: Theme.of(context).textTheme.bodySmall,
          ),
        ],
      ),
    );
  }

  /// Turning it OFF is immediate — withdrawing a permission must never be
  /// harder than granting it. Turning it ON goes through the explanation
  /// first, and only a deliberate confirmation flips the flag.
  Future<void> _alternar(
    BuildContext context,
    EstadoVisualizador estado,
    bool habilitada,
  ) async {
    if (!habilitada) {
      await estado.cambiarOndaReal(false);
      return;
    }
    final l10n = AppLocalizations.of(context);
    final confirmado = await showDialog<bool>(
      context: context,
      builder:
          (ctx) => AlertDialog(
            key: const ValueKey('visualizador-explicacion-permiso'),
            title: Text(l10n.visualizerRealWaveTitle),
            content: Text(l10n.visualizerRealWavePermissionExplanation),
            actions: [
              TextButton(
                onPressed: () => Navigator.pop(ctx, false),
                child: Text(l10n.cancelAction),
              ),
              FilledButton(
                onPressed: () => Navigator.pop(ctx, true),
                child: Text(l10n.visualizerRealWaveEnableAction),
              ),
            ],
          ),
    );
    if (confirmado != true) return;
    await estado.cambiarOndaReal(true);
  }
}