import 'package:flutter/material.dart';
import 'package:friendly_map/modules/discovery/discovery.dart';
import 'package:qr_flutter/qr_flutter.dart' show QrImageView;

import '../app_scope.dart';
import '../theme.dart';
import '../widgets/async_view.dart';
import '../widgets/common.dart';

/// 내 QR: 상대가 읽으면 내 번호·이름·공개 키가 전해져 바로 친구 요청이 간다.
class MyQrScreen extends StatelessWidget {
  const MyQrScreen({super.key});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('내 QR')),
      body: AsyncView<QrPayload?>(
        load: (app) => app.friends.myQr(),
        builder: (context, q) {
          if (q == null) return const EmptyNote('내 정보를 먼저 정해 주세요.');
          return Center(
            child: Column(mainAxisSize: MainAxisSize.min, children: [
              Container(
                padding: const EdgeInsets.all(14),
                decoration: BoxDecoration(color: Colors.white, borderRadius: BorderRadius.circular(16)),
                child: QrImageView(data: q.encode(), size: 240, backgroundColor: Colors.white),
              ),
              const SizedBox(height: 20),
              Text(q.name, style: const TextStyle(fontSize: 20, fontWeight: FontWeight.w700)),
              const SizedBox(height: 4),
              Text(q.phone, style: const TextStyle(color: Pal.muted)),
              const SizedBox(height: 16),
              const Padding(
                padding: EdgeInsets.symmetric(horizontal: 32),
                child: Text('상대가 Friendly Map 으로 이 QR 을 읽으면 서로 명함을 교환할 수 있어요.',
                    textAlign: TextAlign.center, style: TextStyle(color: Pal.muted, height: 1.5)),
              ),
            ]),
          );
        },
      ),
    );
  }
}

/// 상대의 QR 을 카메라로 읽어 친구를 추가한다.
class ScanQrScreen extends StatefulWidget {
  const ScanQrScreen({super.key});

  @override
  State<ScanQrScreen> createState() => _ScanQrScreenState();
}

class _ScanQrScreenState extends State<ScanQrScreen> {
  bool _handled = false;

  Future<void> _onCode(String code) async {
    if (_handled) return;
    _handled = true;
    final p = await AppScope.of(context).app.friends.addFromQr(code);
    if (!mounted) return;
    if (p == null) {
      _handled = false;
      showNote(context, 'Friendly Map 의 QR 이 아니에요.');
      return;
    }
    showNote(context, '${p.name}님에게 친구 요청을 보냈어요.');
    Navigator.pop(context);
  }

  @override
  Widget build(BuildContext context) {
    final factory = AppScope.of(context).qr;
    return Scaffold(
      appBar: AppBar(title: const Text('QR 읽기')),
      body: factory == null
          ? const EmptyNote('이 기기에서는 카메라를 쓸 수 없어요.')
          : factory.build(onCode: _onCode),
    );
  }
}