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

import '../estado/estado_alarmas.dart';
import '../l10n/gen/app_localizations.dart';
import '../servicios/diagnostico_alarmas.dart';
import '../servicios/servicio_alarmas_android.dart';
import '../tema/pluriwave_theme.dart';
import '../widgets/pluri_glass_surface.dart';
import '../widgets/pluri_layout.dart';
import '../widgets/pluri_push_scaffold.dart';

/// Full Android alarm-reliability diagnostics screen (fix/alarmas-fiabilidad).
///
/// Replaces the old one-line `_AccesoDiagnostico` button in
/// `pantalla_alarmas.dart`, which only ever surfaced 3 of the 6 fields
/// `DiagnosticoAlarmasAndroid` collects. This screen shows all five
/// diagnosable signals with a clear ok/needs-attention state, a "Fix this"
/// action that opens the right system settings screen for each failing one,
/// plus manufacturer-specific guidance for vendors known to require manually
/// enabling Autostart.
class PantallaDiagnosticoAlarmas extends StatelessWidget {
  const PantallaDiagnosticoAlarmas({super.key});

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context);
    final estado = context.watch<EstadoAlarmas>();
    final diag = estado.diagnostico;

    return PluriPushScaffold(
      title: l10n.androidReliabilityTitle,
      body:
          diag == null
              ? ListView(
                padding: PluriLayout.pageContentPadding,
                children: [
                  PluriGlassSurface(
                    child: Text(l10n.alarmDiagnosticsUnavailableHint),
                  ),
                ],
              )
              : _CuerpoDiagnostico(estado: estado, diag: diag),
    );
  }
}

class _CuerpoDiagnostico extends StatelessWidget {
  const _CuerpoDiagnostico({required this.estado, required this.diag});

  final EstadoAlarmas estado;
  final DiagnosticoAlarmasAndroid diag;

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context);
    final items = construirItemsDiagnosticoAlarmas(
      diagnostico: diag,
      hayAlarmasActivas: estado.alarmas.any((alarma) => alarma.activa),
    );
    final mostrarAutostart = fabricanteRequiereGuiaAutostart(diag.fabricante);

    return ListView(
      padding: PluriLayout.pageContentPadding,
      children: [
        for (final item in items) ...[
          _FilaDiagnostico(item: item, estado: estado, diag: diag),
          const SizedBox(height: 10),
        ],
        const SizedBox(height: 6),
        PluriGlassSurface(
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              _FilaInformativa(
                titulo: l10n.alarmDiagnosticsManufacturerLabel,
                valor: diag.fabricante,
              ),
              const SizedBox(height: 10),
              _FilaInformativa(
                titulo: l10n.alarmDiagnosticsSdkLabel,
                valor: diag.versionSdk.toString(),
              ),
            ],
          ),
        ),
        if (mostrarAutostart) ...[
          const SizedBox(height: 16),
          _GuiaAutostart(fabricante: diag.fabricante),
        ],
      ],
    );
  }
}

class _FilaDiagnostico extends StatelessWidget {
  const _FilaDiagnostico({
    required this.item,
    required this.estado,
    required this.diag,
  });

  final ItemDiagnosticoAlarma item;
  final EstadoAlarmas estado;
  final DiagnosticoAlarmasAndroid diag;

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context);
    final tokens = context.pluriTokens;
    final ok = item.estado == EstadoSenalDiagnostico.ok;
    final color = ok ? tokens.liveGreen : Theme.of(context).colorScheme.error;
    final esConteoNativo =
        item.senal == SenalDiagnosticoAlarma.alarmasNativasPendientes;

    return PluriGlassSurface(
      child: Row(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Icon(
            ok ? Icons.check_circle_rounded : Icons.warning_amber_rounded,
            color: color,
          ),
          const SizedBox(width: 12),
          Expanded(
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Row(
                  children: [
                    Expanded(
                      child: Text(
                        _tituloSenal(l10n, item.senal),
                        style: const TextStyle(fontWeight: FontWeight.w700),
                      ),
                    ),
                    Text(
                      ok
                          ? l10n.statusOk
                          : l10n.alarmDiagnosticsNeedsAttentionStatus,
                      style: TextStyle(
                        color: color,
                        fontWeight: FontWeight.w700,
                      ),
                    ),
                  ],
                ),
                const SizedBox(height: 4),
                if (esConteoNativo) ...[
                  Text(
                    l10n.alarmDiagnosticsNativeCountValue(
                      diag.alarmasNativasPendientes,
                    ),
                  ),
                  if (!ok) ...[
                    const SizedBox(height: 4),
                    Text(l10n.alarmDiagnosticsNativeCountAttentionHint),
                  ],
                ] else
                  Text(_hintSenal(l10n, item.senal)),
                if (!ok && item.accion != AccionDiagnosticoAlarma.ninguna) ...[
                  const SizedBox(height: 8),
                  Align(
                    alignment: Alignment.centerRight,
                    child: OutlinedButton(
                      onPressed: () => _ejecutarAccion(context, l10n),
                      child: Text(l10n.alarmDiagnosticsFixAction),
                    ),
                  ),
                ],
              ],
            ),
          ),
        ],
      ),
    );
  }

  /// Runs the system action for [item.accion] and reloads the diagnostic
  /// snapshot. Never throws across the widget boundary: every underlying
  /// `PuertoAlarmasAndroid` call already reports `false` instead (native side
  /// catches any intent-resolution failure), and a `false` here surfaces a
  /// calm SnackBar instead of leaving the tap looking like a no-op.
  Future<void> _ejecutarAccion(
    BuildContext context,
    AppLocalizations l10n,
  ) async {
    final resuelto = switch (item.accion) {
      AccionDiagnosticoAlarma.abrirAlarmasExactas =>
        await estado.android.solicitarPermisoAlarmasExactas(),
      AccionDiagnosticoAlarma.abrirNotificaciones =>
        await estado.android.abrirConfiguracionNotificaciones(),
      AccionDiagnosticoAlarma.abrirOptimizacionBateria =>
        await estado.android.solicitarExencionBateria(),
      AccionDiagnosticoAlarma.abrirPantallaCompleta =>
        await estado.android.solicitarPermisoPantallaCompleta(),
      AccionDiagnosticoAlarma.ninguna => true,
    };
    await estado.cargarDiagnostico();
    if (!resuelto && context.mounted) {
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(content: Text(l10n.alarmDiagnosticsIntentUnavailable)),
      );
    }
  }
}

String _tituloSenal(AppLocalizations l10n, SenalDiagnosticoAlarma senal) =>
    switch (senal) {
      SenalDiagnosticoAlarma.alarmasExactas =>
        l10n.alarmDiagnosticsExactAlarmsTitle,
      SenalDiagnosticoAlarma.notificaciones =>
        l10n.alarmDiagnosticsNotificationsTitle,
      SenalDiagnosticoAlarma.pantallaCompleta =>
        l10n.alarmDiagnosticsFullScreenTitle,
      SenalDiagnosticoAlarma.optimizacionBateria =>
        l10n.alarmDiagnosticsBatteryTitle,
      SenalDiagnosticoAlarma.alarmasNativasPendientes =>
        l10n.alarmDiagnosticsNativeCountTitle,
    };

/// Static one-line explanation per signal. `alarmasNativasPendientes` builds
/// its own dynamic body in [_FilaDiagnostico] instead (count + conditional
/// attention hint), so this branch is never actually rendered for it -- kept
/// only so the switch stays exhaustive over the enum.
String _hintSenal(
  AppLocalizations l10n,
  SenalDiagnosticoAlarma senal,
) => switch (senal) {
  SenalDiagnosticoAlarma.alarmasExactas => l10n.alarmDiagnosticsExactAlarmsHint,
  SenalDiagnosticoAlarma.notificaciones =>
    l10n.alarmDiagnosticsNotificationsHint,
  SenalDiagnosticoAlarma.pantallaCompleta =>
    l10n.alarmDiagnosticsFullScreenHint,
  SenalDiagnosticoAlarma.optimizacionBateria =>
    l10n.alarmDiagnosticsBatteryHint,
  SenalDiagnosticoAlarma.alarmasNativasPendientes => '',
};

class _FilaInformativa extends StatelessWidget {
  const _FilaInformativa({required this.titulo, required this.valor});

  final String titulo;
  final String valor;

  @override
  Widget build(BuildContext context) {
    return Row(
      mainAxisAlignment: MainAxisAlignment.spaceBetween,
      children: [
        Text(titulo),
        Text(valor, style: const TextStyle(fontWeight: FontWeight.w700)),
      ],
    );
  }
}

/// Manufacturer-specific autostart explanation (fix/alarmas-fiabilidad item
/// 3). Deliberately never claims the app can detect or grant this setting --
/// there is no public API for it, so this is explanation only, never an
/// action button.
class _GuiaAutostart extends StatelessWidget {
  const _GuiaAutostart({required this.fabricante});

  final String fabricante;

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context);
    final tokens = context.pluriTokens;
    return PluriGlassSurface(
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Row(
            children: [
              Icon(Icons.info_outline_rounded, color: tokens.warmCoral),
              const SizedBox(width: 8),
              Expanded(
                child: Text(
                  l10n.alarmDiagnosticsAutostartTitle,
                  style: const TextStyle(fontWeight: FontWeight.w700),
                ),
              ),
            ],
          ),
          const SizedBox(height: 8),
          Text(l10n.alarmDiagnosticsAutostartBody(fabricante)),
        ],
      ),
    );
  }
}