import 'package:flutter/material.dart';
import 'package:pad_scanner/services/api_service.dart';

class AttachmentConfigDialogResult {
  final String determination; // 'has' or 'none'
  final List<AttachmentConfigItemData> items; // empty if 'none'

  const AttachmentConfigDialogResult({
    required this.determination,
    required this.items,
  });
}

/// Show the attachment configuration dialog for an order.
///
/// [categories] — the full active category list from GET /attachment/categories.
/// [prefillItems] — existing attachment status items (for pre-fill when
///   determination is already 'has' due to earlier attachment arrival).
/// [erpQuantity] — default expected_qty per selected type.
Future<AttachmentConfigDialogResult?> showAttachmentConfigDialog({
  required BuildContext context,
  required String zongpaiNo,
  required List<AttachmentCategoryData> categories,
  required List<AttachmentStatusItemData> prefillItems,
  required int erpQuantity,
}) {
  return showDialog<AttachmentConfigDialogResult>(
    context: context,
    barrierDismissible: false,
    builder: (ctx) => _AttachmentConfigDialog(
      zongpaiNo: zongpaiNo,
      categories: categories,
      prefillItems: prefillItems,
      erpQuantity: erpQuantity,
    ),
  );
}

class _AttachmentConfigDialog extends StatefulWidget {
  final String zongpaiNo;
  final List<AttachmentCategoryData> categories;
  final List<AttachmentStatusItemData> prefillItems;
  final int erpQuantity;

  const _AttachmentConfigDialog({
    required this.zongpaiNo,
    required this.categories,
    required this.prefillItems,
    required this.erpQuantity,
  });

  @override
  State<_AttachmentConfigDialog> createState() =>
      _AttachmentConfigDialogState();
}

class _AttachmentConfigDialogState extends State<_AttachmentConfigDialog> {
  late Map<int, bool> _selected; // category_id → checked
  late Map<int, TextEditingController> _controllers; // category_id → qty

  @override
  void initState() {
    super.initState();
    _selected = {};
    _controllers = {};
    final prefillSet = <int>{};
    for (final item in widget.prefillItems) {
      _selected[item.categoryId] = true;
      prefillSet.add(item.categoryId);
    }
    for (final cat in widget.categories) {
      if (!_selected.containsKey(cat.id)) {
        _selected[cat.id] = prefillSet.contains(cat.id);
      }
      final ctrl = TextEditingController(
        text: prefillSet.contains(cat.id)
            ? widget.prefillItems
                  .firstWhere((i) => i.categoryId == cat.id)
                  .expectedQty
                  .toString()
            : widget.erpQuantity.toString(),
      );
      _controllers[cat.id] = ctrl;
    }
  }

  @override
  void dispose() {
    for (final ctrl in _controllers.values) {
      ctrl.dispose();
    }
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final hasAnyChecked = _selected.values.any((v) => v);

    return AlertDialog(
      title: Text('${widget.zongpaiNo} — 附件配置'),
      content: SizedBox(
        width: 500,
        child: SingleChildScrollView(
          child: Column(
            mainAxisSize: MainAxisSize.min,
            children: [
              const Text(
                '请勾选本订单携带的附件类型，并确认每种数量：',
                style: TextStyle(fontSize: 13),
              ),
              const SizedBox(height: 8),
              ...widget.categories.map(
                (cat) => CheckboxListTile(
                  dense: true,
                  title: Text(cat.name, style: const TextStyle(fontSize: 14)),
                  subtitle: Row(
                    children: [
                      const Text('应到: ', style: TextStyle(fontSize: 12)),
                      SizedBox(
                        width: 80,
                        child: TextField(
                          controller: _controllers[cat.id],
                          keyboardType: TextInputType.number,
                          enabled: _selected[cat.id] == true,
                          style: const TextStyle(fontSize: 14),
                          decoration: const InputDecoration(
                            isDense: true,
                            contentPadding: EdgeInsets.symmetric(
                              vertical: 4,
                              horizontal: 8,
                            ),
                          ),
                        ),
                      ),
                    ],
                  ),
                  value: _selected[cat.id] ?? false,
                  onChanged: (v) =>
                      setState(() => _selected[cat.id] = v ?? false),
                ),
              ),
            ],
          ),
        ),
      ),
      actions: [
        TextButton(
          onPressed: () => Navigator.pop(context),
          child: const Text('取消'),
        ),
        TextButton(
          onPressed: () {
            Navigator.pop(
              context,
              AttachmentConfigDialogResult(determination: 'none', items: []),
            );
          },
          child: const Text('无附件'),
        ),
        ElevatedButton(
          onPressed: hasAnyChecked
              ? () {
                  final items = <AttachmentConfigItemData>[];
                  for (final cat in widget.categories) {
                    if (_selected[cat.id] == true) {
                      final qty =
                          int.tryParse(_controllers[cat.id]!.text.trim()) ??
                          widget.erpQuantity;
                      items.add(
                        AttachmentConfigItemData(
                          categoryId: cat.id,
                          expectedQty: qty,
                        ),
                      );
                    }
                  }
                  Navigator.pop(
                    context,
                    AttachmentConfigDialogResult(
                      determination: 'has',
                      items: items,
                    ),
                  );
                }
              : null,
          child: const Text('确认'),
        ),
      ],
    );
  }
}