import 'package:sysfarma_mobile/src/app/widgets/app_panel.dart';
import 'package:sysfarma_mobile/src/core/network/api_client.dart';
import 'package:sysfarma_mobile/src/core/theme/app_tokens.dart';
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';

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

  @override
  ConsumerState<InventoryReportScreen> createState() =>
      _InventoryReportScreenState();
}

class _InventoryReportScreenState
    extends ConsumerState<InventoryReportScreen> {
  bool _isLoading = true;
  Map<String, dynamic> _data = const {};

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

  Future<void> _refresh() async {
    if (mounted) setState(() => _isLoading = true);
    final response = await ref.read(apiClientProvider).inventoryReport();
    if (!mounted) return;
    setState(() {
      _data = response.data ?? const {};
      _isLoading = false;
    });
  }

  String _fmtCurrency(Object? value) {
    if (value == null) return 'S/ 0.00';
    final n = double.tryParse(value.toString()) ?? 0.0;
    return 'S/ ${n.toStringAsFixed(2)}';
  }

  @override
  Widget build(BuildContext context) {
    final totals = Map<String, dynamic>.from(_data['totals'] as Map? ?? const {});
    final items = List<Map<String, dynamic>>.from(_data['items'] as List? ?? const []);

    return SafeArea(
      child: RefreshIndicator(
        onRefresh: _refresh,
        child: ListView(
          padding: AppTokens.pagePadding,
          children: [
            if (_isLoading)
              const Padding(
                padding: EdgeInsets.symmetric(vertical: 32),
                child: Center(child: CircularProgressIndicator()),
              )
            else ...[
              AppPanel(
                title: 'Resumen consolidado',
                child: Column(
                  children: [
                    _Line(label: 'Stock total', value: '${totals['stock'] ?? 0} u'),
                    const Divider(height: 22),
                    _Line(label: 'Costo', value: _fmtCurrency(totals['stock_cost_value'])),
                    const Divider(height: 22),
                    _Line(label: 'Valor de venta', value: _fmtCurrency(totals['stock_sale_value'])),
                    const Divider(height: 22),
                    _Line(label: 'Utilidad potencial', value: _fmtCurrency(totals['potential_profit'])),
                  ],
                ),
              ),
              const SizedBox(height: 14),
              AppPanel(
                title: 'Top valorizados',
                child: Column(
                  children: [
                    for (final item in items) ...[
                      _ItemRow(item: item, formatter: _fmtCurrency),
                      if (item != items.last) const Divider(height: 16),
                    ],
                  ],
                ),
              ),
            ],
          ],
        ),
      ),
    );
  }
}

class _Line extends StatelessWidget {
  const _Line({required this.label, required this.value});
  final String label;
  final String value;

  @override
  Widget build(BuildContext context) {
    return Row(
      children: [
        Expanded(
          child: Text(
            label,
            style: Theme.of(context).textTheme.bodyMedium?.copyWith(color: AppTokens.secondary),
          ),
        ),
        Text(
          value,
          style: Theme.of(context).textTheme.titleSmall?.copyWith(fontWeight: FontWeight.w700),
        ),
      ],
    );
  }
}

class _ItemRow extends StatelessWidget {
  const _ItemRow({required this.item, required this.formatter});
  final Map<String, dynamic> item;
  final String Function(Object?) formatter;

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.symmetric(vertical: 4),
      child: Row(
        children: [
          Expanded(
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Text(
                  item['description']?.toString() ?? '-',
                  maxLines: 1,
                  overflow: TextOverflow.ellipsis,
                  style: Theme.of(context).textTheme.titleSmall,
                ),
                const SizedBox(height: 2),
                Text(
                  '${item['stock'] ?? 0} u',
                  style: Theme.of(context).textTheme.labelSmall?.copyWith(
                        color: AppTokens.secondary,
                      ),
                ),
              ],
            ),
          ),
          Text(
            formatter(item['potential_profit']),
            style: Theme.of(context).textTheme.titleSmall?.copyWith(
                  color: AppTokens.primary,
                  fontWeight: FontWeight.w700,
                ),
          ),
        ],
      ),
    );
  }
}