import 'package:sysfarma_mobile/src/core/storage/tenant_session_store.dart';
import 'package:sysfarma_mobile/src/core/theme/app_tokens.dart';
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';
import 'package:url_launcher/url_launcher.dart';

const _privacyPolicyUrl = 'https://sysfarma.pe/politica-de-privacidad';

class SettingsScreen extends ConsumerStatefulWidget {
  const SettingsScreen({super.key});

  @override
  ConsumerState<SettingsScreen> createState() => _SettingsScreenState();
}

class _SettingsScreenState extends ConsumerState<SettingsScreen> {
  @override
  Widget build(BuildContext context) {
    final sessionAsync = ref.watch(currentSessionProvider);
    final session = sessionAsync.maybeWhen(
      data: (s) => s,
      orElse: () => null,
    );
    bool hasModule(String value) => session?.hasModule(value) ?? false;

    final options = <_OptionEntry>[
      _OptionEntry(
        icon: Icons.person_rounded,
        title: 'Mi perfil',
        accent: AppTokens.primary,
        onTap: () => context.go('/profile'),
      ),
      _OptionEntry(
        icon: Icons.sync_problem_rounded,
        title: 'Pendientes sync',
        accent: AppTokens.warning,
        onTap: () => context.go('/pending-sync'),
      ),
      if (hasModule('items')) ...[
        _OptionEntry(
          icon: Icons.inventory_2_rounded,
          title: 'Productos',
          accent: AppTokens.primary,
          onTap: () => context.go('/catalog'),
        ),
        _OptionEntry(
          icon: Icons.design_services_rounded,
          title: 'Servicios',
          accent: AppTokens.cta,
          onTap: () => context.go('/services'),
        ),
      ],
      if (hasModule('persons'))
        _OptionEntry(
          icon: Icons.people_alt_rounded,
          title: 'Clientes',
          accent: AppTokens.success,
          onTap: () => context.go('/customers'),
        ),
      // Proveedores cuelga de Compras en la web, no de Clientes (ver
      // ModuleAccess.routeModules).
      if (hasModule('purchases')) ...[
        _OptionEntry(
          icon: Icons.local_shipping_rounded,
          title: 'Proveedores',
          accent: AppTokens.cta,
          onTap: () => context.go('/suppliers'),
        ),
        _OptionEntry(
          icon: Icons.shopping_bag_rounded,
          title: 'Compras',
          accent: AppTokens.warning,
          onTap: () => context.go('/purchases'),
        ),
      ],
      if (hasModule('documents')) ...[
        _OptionEntry(
          icon: Icons.receipt_long_rounded,
          title: 'Ventas emitidas',
          accent: AppTokens.primary,
          onTap: () => context.go('/sales-history'),
        ),
        _OptionEntry(
          icon: Icons.hourglass_top_rounded,
          title: 'Por anular',
          accent: AppTokens.warning,
          onTap: () => context.go('/pending-voided'),
        ),
        _OptionEntry(
          icon: Icons.cloud_sync_rounded,
          title: 'Consulta SUNAT',
          accent: AppTokens.secondary,
          onTap: () => context.go('/quick'),
        ),
      ],
      // Bandeja de pagos Yape/Plin (addon superadmin). La escucha solo para
      // el usuario designado como capturador.
      if (session?.yapeInboxEnabled ?? false) ...[
        _OptionEntry(
          icon: Icons.account_balance_wallet_rounded,
          title: 'Pagos Yape',
          accent: const Color(0xFF742384),
          onTap: () => context.go('/yape-inbox'),
        ),
        if (session?.yapeListenerEnabled ?? false)
          _OptionEntry(
            icon: Icons.hearing_rounded,
            title: 'Escuchar pagos en este celular',
            accent: AppTokens.success,
            onTap: () => context.push('/yape-listener'),
          ),
      ],
      // Al final: no es una funcion operativa, es informativa.
      _OptionEntry(
        icon: Icons.privacy_tip_rounded,
        title: 'Política de privacidad',
        accent: AppTokens.secondary,
        onTap: () => launchUrl(
          Uri.parse(_privacyPolicyUrl),
          mode: LaunchMode.externalApplication,
        ),
      ),
    ];

    return SafeArea(
      child: ListView(
        padding: AppTokens.pagePadding,
        children: [
          GridView.builder(
            shrinkWrap: true,
            physics: const NeverScrollableScrollPhysics(),
            itemCount: options.length,
            gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
              crossAxisCount: 2,
              crossAxisSpacing: 12,
              mainAxisSpacing: 12,
              childAspectRatio: 1.15,
            ),
            itemBuilder: (context, index) {
              final option = options[index];
              return _OptionCard(entry: option);
            },
          ),
        ],
      ),
    );
  }
}

class _OptionEntry {
  const _OptionEntry({
    required this.icon,
    required this.title,
    required this.accent,
    required this.onTap,
  });

  final IconData icon;
  final String title;
  final Color accent;
  final VoidCallback onTap;
}

class _OptionCard extends StatelessWidget {
  const _OptionCard({required this.entry});

  final _OptionEntry entry;

  @override
  Widget build(BuildContext context) {
    return Material(
      color: AppTokens.surface,
      borderRadius: BorderRadius.circular(AppTokens.radiusMedium),
      child: InkWell(
        onTap: entry.onTap,
        borderRadius: BorderRadius.circular(AppTokens.radiusMedium),
        child: Container(
          padding: const EdgeInsets.all(16),
          decoration: BoxDecoration(
            borderRadius: BorderRadius.circular(AppTokens.radiusMedium),
            border: Border.all(color: AppTokens.border),
          ),
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            mainAxisSize: MainAxisSize.min,
            children: [
              Container(
                width: 48,
                height: 48,
                decoration: BoxDecoration(
                  color: entry.accent.withValues(alpha: 0.12),
                  borderRadius: BorderRadius.circular(14),
                ),
                child: Icon(entry.icon, color: entry.accent, size: 26),
              ),
              const SizedBox(height: 12),
              // Flexible (no solo maxLines/ellipsis): con titulos largos como
              // "Política de privacidad" + texto de sistema mas grande
              // (accesibilidad), el Column pedia mas alto que la celda fija
              // del grid y tiraba "RenderFlex overflowed" - Flexible deja que
              // el texto se comprima en vez de reventar el layout.
              Flexible(
                child: Text(
                  entry.title,
                  maxLines: 2,
                  overflow: TextOverflow.ellipsis,
                  style: Theme.of(context).textTheme.titleSmall?.copyWith(
                        fontWeight: FontWeight.w700,
                      ),
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }
}