import 'package:sysfarma_mobile/src/app/widgets/app_loader.dart';
import 'package:sysfarma_mobile/src/app/widgets/app_panel.dart';
import 'package:sysfarma_mobile/src/app/widgets/empty_state_panel.dart';
import 'package:sysfarma_mobile/src/core/network/api_client.dart';
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';

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

  @override
  ConsumerState<PendingVoidedScreen> createState() =>
      _PendingVoidedScreenState();
}

class _PendingVoidedScreenState extends ConsumerState<PendingVoidedScreen> {
  List<Map<String, dynamic>> _items = const [];
  bool _isLoading = true;
  bool _canAnular = true;
  // Ids con una accion SUNAT en curso (deshabilita los botones de esa fila
  // y muestra spinner) y ids en fade-out antes de sacarlos de _items.
  final Set<int> _processingIds = {};
  final Set<int> _removingIds = {};

  @override
  void initState() {
    super.initState();
    _loadPermission();
    _refresh();
  }

  Future<void> _loadPermission() async {
    final session = await ref.read(tenantSessionStoreProvider).readSession();
    if (!mounted) return;
    setState(() {
      _canAnular = (session?.annularSale ?? true) || (session?.isAdmin ?? true);
    });
  }

  Future<void> _refresh() async {
    if (mounted) setState(() => _isLoading = true);
    final response = await ref.read(apiClientProvider).documents(
          perPage: 50,
          page: 1,
          model: 'document',
          stateTypeId: '13',
        );
    if (!mounted) return;
    setState(() {
      _items = response.data ?? const [];
      _isLoading = false;
    });
  }

  Future<void> _removeItemAnimated(int id) async {
    setState(() => _removingIds.add(id));
    await Future.delayed(const Duration(milliseconds: 200));
    if (!mounted) return;
    setState(() {
      _items =
          _items.where((row) => int.tryParse('${row['id']}') != id).toList();
      _removingIds.remove(id);
    });
  }

  Future<void> _confirm(Map<String, dynamic> record) async {
    final id = int.tryParse('${record['id']}') ?? 0;
    if (id <= 0) return;
    final go = await showDialog<bool>(
      context: context,
      builder: (ctx) => AlertDialog(
        title: const Text('Confirmar anulación'),
        content: const Text(
            'Confirma que el comprobante quedará marcado como anulado. Recuerda enviar la comunicación de baja a SUNAT desde la web.'),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(ctx, false),
            child: const Text('Cancelar'),
          ),
          FilledButton(
            onPressed: () => Navigator.pop(ctx, true),
            child: const Text('Confirmar'),
          ),
        ],
      ),
    );
    if (go != true || !mounted) return;
    setState(() => _processingIds.add(id));
    final response =
        await ref.read(apiClientProvider).confirmAnularDocument(id: id);
    if (!mounted) return;
    setState(() => _processingIds.remove(id));
    if (response.success) {
      await _removeItemAnimated(id);
    }
    if (!mounted) return;
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        content: Text(response.message ?? (response.success ? 'OK' : 'Error')),
        backgroundColor:
            response.success ? AppTokens.success : AppTokens.danger,
      ),
    );
  }

  Future<void> _sendToSunat(Map<String, dynamic> record) async {
    final id = int.tryParse('${record['id']}') ?? 0;
    if (id <= 0) return;
    final controller =
        TextEditingController(text: 'Anulación de la operación');
    final motivo = await showDialog<String>(
      context: context,
      builder: (ctx) => AlertDialog(
        title: const Text('Enviar comunicación de baja'),
        content: Column(
          mainAxisSize: MainAxisSize.min,
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: [
            const Text(
                'Indica el motivo de la anulación. Se enviará a SUNAT y el comprobante quedará definitivamente anulado.'),
            const SizedBox(height: 12),
            TextField(
              controller: controller,
              maxLines: 2,
              decoration: const InputDecoration(
                labelText: 'Motivo',
                border: OutlineInputBorder(),
              ),
            ),
          ],
        ),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(ctx),
            child: const Text('Cancelar'),
          ),
          FilledButton.icon(
            style: FilledButton.styleFrom(backgroundColor: AppTokens.warning),
            onPressed: () => Navigator.pop(ctx, controller.text.trim()),
            icon: const Icon(Icons.send_rounded, size: 18),
            label: const Text('Enviar SUNAT'),
          ),
        ],
      ),
    );
    if (motivo == null || motivo.isEmpty || !mounted) return;
    setState(() => _processingIds.add(id));
    final response = await ref
        .read(apiClientProvider)
        .voidedSunatDocument(id: id, description: motivo);
    if (!mounted) return;
    setState(() => _processingIds.remove(id));
    if (response.success) {
      await _removeItemAnimated(id);
    }
    if (!mounted) return;
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        content: Text(response.message ?? (response.success ? 'OK' : 'Error')),
        backgroundColor:
            response.success ? AppTokens.success : AppTokens.danger,
      ),
    );
  }

  Future<void> _cancel(Map<String, dynamic> record) async {
    final id = int.tryParse('${record['id']}') ?? 0;
    if (id <= 0) return;
    final go = await showDialog<bool>(
      context: context,
      builder: (ctx) => AlertDialog(
        title: const Text('Cancelar anulación'),
        content: const Text(
            'El comprobante volverá a estar activo y el stock se descontará de nuevo. ¿Continuar?'),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(ctx, false),
            child: const Text('No'),
          ),
          FilledButton(
            style: FilledButton.styleFrom(backgroundColor: AppTokens.danger),
            onPressed: () => Navigator.pop(ctx, true),
            child: const Text('Sí, revertir'),
          ),
        ],
      ),
    );
    if (go != true || !mounted) return;
    setState(() => _processingIds.add(id));
    final response =
        await ref.read(apiClientProvider).cancelAnularDocument(id: id);
    if (!mounted) return;
    setState(() => _processingIds.remove(id));
    if (response.success) {
      await _removeItemAnimated(id);
    }
    if (!mounted) return;
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        content: Text(response.message ?? (response.success ? 'OK' : 'Error')),
        backgroundColor:
            response.success ? AppTokens.success : AppTokens.danger,
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return SafeArea(
      child: RefreshIndicator(
        onRefresh: _refresh,
        child: ListView(
          padding: AppTokens.pagePadding,
          children: [
            AppPanel(
              title: 'Por anular',
              subtitle:
                  'Comprobantes marcados para anular. Confirma para dejarlos como anulados; recuerda enviar la comunicación de baja desde la web.',
              trailing: Text(
                '${_items.length}',
                style: Theme.of(context).textTheme.titleMedium?.copyWith(
                      color: AppTokens.primary,
                      fontWeight: FontWeight.w700,
                    ),
              ),
              child: _isLoading
                  ? const Padding(
                      padding: EdgeInsets.symmetric(vertical: 24),
                      child: AppLoader(),
                    )
                  : _items.isEmpty
                      ? const EmptyStatePanel(
                          icon: Icons.check_circle_outline_rounded,
                          title: 'Sin pendientes',
                          subtitle:
                              'No hay comprobantes pendientes de anular.',
                        )
                      : Column(
                          children: [
                            for (final item in _items) ...[
                              Builder(builder: (context) {
                                final id =
                                    int.tryParse('${item['id']}') ?? 0;
                                final removing = _removingIds.contains(id);
                                return AnimatedOpacity(
                                  duration:
                                      const Duration(milliseconds: 200),
                                  opacity: removing ? 0 : 1,
                                  child: AnimatedSize(
                                    duration:
                                        const Duration(milliseconds: 200),
                                    curve: Curves.easeOut,
                                    alignment: Alignment.topCenter,
                                    child: removing
                                        ? const SizedBox.shrink()
                                        : _PendingVoidedRow(
                                            record: item,
                                            canAnular: _canAnular,
                                            isProcessing: _processingIds
                                                .contains(id),
                                            onConfirm: () => _confirm(item),
                                            onCancel: () => _cancel(item),
                                            onSendSunat: () =>
                                                _sendToSunat(item),
                                          ),
                                  ),
                                );
                              }),
                              if (item != _items.last)
                                const Divider(height: 16),
                            ],
                          ],
                        ),
            ),
          ],
        ),
      ),
    );
  }
}

class _PendingVoidedRow extends StatelessWidget {
  const _PendingVoidedRow({
    required this.record,
    required this.canAnular,
    required this.isProcessing,
    required this.onConfirm,
    required this.onCancel,
    required this.onSendSunat,
  });

  final Map<String, dynamic> record;
  final bool canAnular;
  final bool isProcessing;
  final VoidCallback onConfirm;
  final VoidCallback onCancel;
  final VoidCallback onSendSunat;

  static const _spinner = SizedBox(
    width: 16,
    height: 16,
    child: CircularProgressIndicator(strokeWidth: 2),
  );

  @override
  Widget build(BuildContext context) {
    final number = record['number_full']?.toString() ??
        '${record['series'] ?? ''}-${record['number'] ?? ''}';
    final customer = record['customer_name']?.toString() ??
        record['customer']?['name']?.toString() ??
        'Cliente varios';
    final total = record['total']?.toString() ?? '0.00';
    final dateOfIssue = record['date_of_issue']?.toString() ?? '-';

    return Padding(
      padding: const EdgeInsets.symmetric(vertical: 6),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.stretch,
        children: [
          Row(
            children: [
              CircleAvatar(
                radius: 18,
                backgroundColor: AppTokens.warning.withValues(alpha: 0.15),
                foregroundColor: AppTokens.warning,
                child: const Icon(Icons.hourglass_top_rounded, size: 18),
              ),
              const SizedBox(width: 12),
              Expanded(
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(
                      number,
                      maxLines: 1,
                      overflow: TextOverflow.ellipsis,
                      style: Theme.of(context).textTheme.titleSmall,
                    ),
                    const SizedBox(height: 2),
                    Text(
                      customer,
                      maxLines: 1,
                      overflow: TextOverflow.ellipsis,
                      style: Theme.of(context).textTheme.bodySmall?.copyWith(
                            color: AppTokens.secondary,
                          ),
                    ),
                    const SizedBox(height: 2),
                    Text(
                      dateOfIssue,
                      style: Theme.of(context).textTheme.labelSmall?.copyWith(
                            color: AppTokens.secondary,
                          ),
                    ),
                  ],
                ),
              ),
              const SizedBox(width: 8),
              Text(
                'S/ $total',
                style: Theme.of(context).textTheme.titleSmall?.copyWith(
                      color: AppTokens.textPrimary,
                      fontWeight: FontWeight.w700,
                    ),
              ),
            ],
          ),
          if (canAnular) ...[
            const SizedBox(height: 8),
            Row(
              children: [
                Expanded(
                  child: OutlinedButton.icon(
                    onPressed: isProcessing ? null : onCancel,
                    style: OutlinedButton.styleFrom(
                      foregroundColor: AppTokens.secondary,
                      side: BorderSide(
                          color:
                              AppTokens.secondary.withValues(alpha: 0.40)),
                    ),
                    icon: isProcessing
                        ? _spinner
                        : const Icon(Icons.undo_rounded, size: 18),
                    label: const Text('Revertir'),
                  ),
                ),
                const SizedBox(width: 8),
                Expanded(
                  child: FilledButton.icon(
                    onPressed: isProcessing ? null : onConfirm,
                    icon: isProcessing
                        ? _spinner
                        : const Icon(Icons.check_rounded, size: 18),
                    label: const Text('Confirmar'),
                  ),
                ),
              ],
            ),
          ],
          const SizedBox(height: 6),
          SizedBox(
            width: double.infinity,
            child: FilledButton.icon(
              onPressed: isProcessing ? null : onSendSunat,
              style: FilledButton.styleFrom(
                backgroundColor: AppTokens.warning,
                foregroundColor: Colors.white,
              ),
              icon: isProcessing
                  ? const SizedBox(
                      width: 16,
                      height: 16,
                      child: CircularProgressIndicator(
                        strokeWidth: 2,
                        color: Colors.white,
                      ),
                    )
                  : const Icon(Icons.cloud_upload_rounded, size: 18),
              label: Text(isProcessing ? 'Enviando...' : 'Enviar SUNAT'),
            ),
          ),
        ],
      ),
    );
  }
}