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

import '../estado/estado_alarmas.dart';
import '../l10n/display_names.dart';
import '../l10n/formato_fechas.dart';
import '../l10n/gen/app_localizations.dart';
import '../modelos/alarma_musical.dart';
import '../tema/pluriwave_theme.dart';
import '../widgets/pluri_glass_surface.dart';
import '../widgets/pluri_layout.dart';
import '../widgets/pluri_push_scaffold.dart';

/// Vacaciones manager (design ADR-6, `alarm-vacation-ranges` spec, WU9):
/// active-range hero (name + days-remaining + per-alarm impact line), the
/// "PROGRAMADOS" upcoming list, an "Añadir rango" CTA, and a "Rangos
/// pasados" history section. This is the REAL destination WU8's Alarmas-
/// root summary row pushes to, replacing WU8's own temporary placeholder
/// (`_PantallaVacacionesTemporal` in `pantalla_alarmas.dart`).
class PantallaVacaciones extends StatelessWidget {
  const PantallaVacaciones({super.key});

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context);
    final estado = context.watch<EstadoAlarmas>();
    final activo = estado.rangoVacacionesActivo();
    final proximas = estado.vacacionesProximas();
    final pasadas = estado.vacacionesPasadas();

    return PluriPushScaffold(
      title: l10n.vacationRangesTitle,
      body: ListView(
        padding: PluriLayout.pageContentPadding,
        children: [
          if (activo != null)
            _HeroRangoActivo(estado: estado, rango: activo)
          else
            PluriGlassSurface(child: Text(l10n.vacationNoActiveRangeHint)),
          const SizedBox(height: 16),
          _SeccionProgramados(proximas: proximas),
          const SizedBox(height: 16),
          Align(
            alignment: Alignment.centerLeft,
            child: OutlinedButton.icon(
              onPressed: () => _abrirAlta(context),
              icon: const Icon(Icons.add_rounded),
              label: Text(l10n.addVacationRangeCta),
            ),
          ),
          const SizedBox(height: 16),
          _SeccionRangosPasados(pasadas: pasadas),
        ],
      ),
    );
  }

  Future<void> _abrirAlta(BuildContext context) async {
    await showModalBottomSheet<void>(
      context: context,
      isScrollControlled: true,
      useSafeArea: true,
      backgroundColor: Colors.transparent,
      builder: (_) => const _EditorVacacionesSheet(),
    );
  }
}

/// Active-range hero: name, days-remaining countdown (reusing WU8's own
/// `vacationSummaryActiveCountdown` string — same concept, bigger stage),
/// a determinate progress bar, and the per-alarm impact line(s) from
/// `EstadoAlarmas.impactoDeRango`.
class _HeroRangoActivo extends StatelessWidget {
  const _HeroRangoActivo({required this.estado, required this.rango});

  final EstadoAlarmas estado;
  final RangoVacaciones rango;

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context);
    final hoy = DateTime.now();
    final hoyDia = DateTime(hoy.year, hoy.month, hoy.day);
    final diasRestantes = rango.finDia.difference(hoyDia).inDays;
    final impacto = estado.impactoDeRango(rango);

    return PluriGlassSurface(
      glowColor: context.pluriTokens.electricMagenta.withValues(alpha: 0.24),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(
            localizedVacationName(l10n, rango.nombre),
            style: Theme.of(
              context,
            ).textTheme.titleLarge?.copyWith(fontWeight: FontWeight.w900),
          ),
          const SizedBox(height: 4),
          Text(l10n.vacationSummaryActiveCountdown(diasRestantes)),
          const SizedBox(height: 10),
          ClipRRect(
            borderRadius: BorderRadius.circular(999),
            child: LinearProgressIndicator(value: _progreso(hoyDia)),
          ),
          if (impacto.pausadas.isNotEmpty) ...[
            const SizedBox(height: 10),
            Text(l10n.vacationImpactPausedLabel(_horas(impacto.pausadas))),
          ],
          if (impacto.noAfectadas.isNotEmpty) ...[
            const SizedBox(height: 4),
            Text(
              l10n.vacationImpactContinuesLabel(_horas(impacto.noAfectadas)),
            ),
          ],
        ],
      ),
    );
  }

  double _progreso(DateTime hoyDia) {
    final totalDias = rango.finDia.difference(rango.inicioDia).inDays + 1;
    if (totalDias <= 0) return 0;
    final transcurridos = hoyDia.difference(rango.inicioDia).inDays + 1;
    return (transcurridos / totalDias).clamp(0.0, 1.0);
  }

  String _horas(List<AlarmaMusical> alarmas) => alarmas
      .map(
        (a) =>
            '${a.hora.toString().padLeft(2, '0')}:${a.minuto.toString().padLeft(2, '0')}',
      )
      .join(', ');
}

class _SeccionProgramados extends StatelessWidget {
  const _SeccionProgramados({required this.proximas});

  final List<RangoVacaciones> proximas;

  @override
  Widget build(BuildContext context) {
    if (proximas.isEmpty) return const SizedBox.shrink();
    final l10n = AppLocalizations.of(context);
    final type = context.pluriType;
    return PluriGlassSurface(
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(l10n.vacationUpcomingSectionTitle, style: type.eyebrowLabel),
          const SizedBox(height: 8),
          for (final rango in proximas)
            ListTile(
              contentPadding: EdgeInsets.zero,
              leading: const Icon(Icons.event_rounded),
              title: Text(localizedVacationName(l10n, rango.nombre)),
              subtitle: Text(_rangoFechas(l10n, rango)),
            ),
        ],
      ),
    );
  }
}

class _SeccionRangosPasados extends StatelessWidget {
  const _SeccionRangosPasados({required this.pasadas});

  final List<RangoVacaciones> pasadas;

  @override
  Widget build(BuildContext context) {
    if (pasadas.isEmpty) return const SizedBox.shrink();
    final l10n = AppLocalizations.of(context);
    final type = context.pluriType;
    return PluriGlassSurface(
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(l10n.vacationPastSectionTitle, style: type.eyebrowLabel),
          const SizedBox(height: 8),
          for (final rango in pasadas)
            ListTile(
              contentPadding: EdgeInsets.zero,
              leading: const Icon(Icons.history_rounded),
              title: Text(localizedVacationName(l10n, rango.nombre)),
              subtitle: Text(_rangoFechas(l10n, rango)),
            ),
        ],
      ),
    );
  }
}

String _rangoFechas(AppLocalizations l10n, RangoVacaciones rango) =>
    '${fechaCortaLocalizada(l10n.localeName, rango.inicioDia)} → '
    '${fechaCortaLocalizada(l10n.localeName, rango.finDia)}';

/// Add-range form. Moved verbatim from `pantalla_alarmas.dart` (WU8's
/// `_PantallaVacacionesTemporal` used it as a placeholder push target; now
/// this screen is the one real consumer). Behaviour unchanged.
class _EditorVacacionesSheet extends StatefulWidget {
  const _EditorVacacionesSheet();

  @override
  State<_EditorVacacionesSheet> createState() => _EditorVacacionesSheetState();
}

class _EditorVacacionesSheetState extends State<_EditorVacacionesSheet> {
  // Created lazily: AppLocalizations.of(context) cannot be read in
  // initState (inherited-widget lookup assert in debug builds).
  TextEditingController? _nombreController;
  late DateTime _inicio;
  late DateTime _fin;

  @override
  void initState() {
    super.initState();
    final hoy = DateTime.now();
    _inicio = DateTime(hoy.year, hoy.month, hoy.day);
    _fin = _inicio.add(const Duration(days: 2));
  }

  @override
  void didChangeDependencies() {
    super.didChangeDependencies();
    _nombreController ??= TextEditingController(
      text: AppLocalizations.of(context).vacationsDefaultName,
    );
  }

  @override
  void dispose() {
    _nombreController?.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context);
    final bottom = MediaQuery.of(context).viewInsets.bottom;
    return Padding(
      padding: EdgeInsets.fromLTRB(12, 12, 12, bottom + 12),
      child: PluriGlassSurface(
        borderRadius: BorderRadius.circular(28),
        padding: const EdgeInsets.all(18),
        child: Column(
          mainAxisSize: MainAxisSize.min,
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Text(
              l10n.newVacationRangeTitle,
              style: Theme.of(
                context,
              ).textTheme.titleLarge?.copyWith(fontWeight: FontWeight.w900),
            ),
            const SizedBox(height: 12),
            TextField(
              controller: _nombreController,
              decoration: InputDecoration(labelText: l10n.nameLabel),
            ),
            const SizedBox(height: 12),
            Row(
              children: [
                Expanded(
                  child: _PickerButton(
                    icon: Icons.play_arrow_rounded,
                    label: l10n.startLabel,
                    value: fechaCortaLocalizada(l10n.localeName, _inicio),
                    onTap: () => _elegirFecha(esInicio: true),
                  ),
                ),
                const SizedBox(width: 10),
                Expanded(
                  child: _PickerButton(
                    icon: Icons.stop_rounded,
                    label: l10n.endLabel,
                    value: fechaCortaLocalizada(l10n.localeName, _fin),
                    onTap: () => _elegirFecha(esInicio: false),
                  ),
                ),
              ],
            ),
            const SizedBox(height: 16),
            FilledButton.icon(
              onPressed: _guardar,
              icon: const Icon(Icons.check_rounded),
              label: Text(l10n.saveRangeAction),
            ),
          ],
        ),
      ),
    );
  }

  Future<void> _elegirFecha({required bool esInicio}) async {
    final actual = esInicio ? _inicio : _fin;
    final hoy = DateTime.now();
    final seleccion = await showDatePicker(
      context: context,
      initialDate: actual,
      firstDate: DateTime(hoy.year, hoy.month, hoy.day),
      lastDate: hoy.add(const Duration(days: 1460)),
    );
    if (seleccion == null) return;
    setState(() {
      if (esInicio) {
        _inicio = seleccion;
        if (_fin.isBefore(_inicio)) _fin = _inicio;
      } else {
        _fin = seleccion;
      }
    });
  }

  Future<void> _guardar() async {
    final estado = context.read<EstadoAlarmas>();
    final rango = estado.servicio.crearRangoVacaciones(
      inicio: _inicio,
      fin: _fin,
      nombre: _nombreController?.text.trim() ?? '',
    );
    await estado.crearRangoVacaciones(rango);
    if (mounted) Navigator.pop(context);
  }
}

class _PickerButton extends StatelessWidget {
  const _PickerButton({
    required this.icon,
    required this.label,
    required this.value,
    required this.onTap,
  });

  final IconData icon;
  final String label;
  final String value;
  final VoidCallback? onTap;

  @override
  Widget build(BuildContext context) {
    return OutlinedButton.icon(
      onPressed: onTap,
      icon: Icon(icon),
      label: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(label, style: Theme.of(context).textTheme.labelSmall),
          Text(value),
        ],
      ),
    );
  }
}