import 'package:flutter/material.dart';
import 'package:nfc_manager/nfc_manager.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'NFC Demo',
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.blue),
        useMaterial3: true,
      ),
      home: const NfcExamplePage(),
    );
  }
}

class NfcExamplePage extends StatefulWidget {
  const NfcExamplePage({super.key});

  @override
  State<NfcExamplePage> createState() => _NfcExamplePageState();
}

class _NfcExamplePageState extends State<NfcExamplePage> {
  String _status = 'App ready';
  String _tagInfo = '';
  bool _isSessionStarted = false;

  @override
  void initState() {
    super.initState();
    NfcManager.instance.isAvailable().then((available) {
      setState(() {
        _status = available ? 'NFC disponible' : 'NFC non disponible';
      });
    });
  }

  void _startSession() async {
    bool available = await NfcManager.instance.isAvailable();
    if (!available) {
      setState(() => _status = 'NFC non disponible');
      return;
    }

    setState(() {
      _status = 'En attente d\'un tag NFC... Approchez le tag';
      _tagInfo = '';
      _isSessionStarted = true;
    });

    // pollingOptions is required on some platforms (Android) to specify techs
    NfcManager.instance.startSession(
      onDiscovered: (dynamic tag) async {
        String info = '';

        // Avoid direct access to tag.data to prevent analyzer issues.
        // We stringify the tag and attempt to extract 'id' if it's a Map.
        try {
          info += 'Raw tag: ${tag.toString()}\n';
          if (tag is Map && tag.containsKey('id')) {
            info += 'ID : ${tag['id']}\n';
          }
        } catch (_) {
          info += 'Impossible de parser le tag\n';
        }

        // If the tag contains NDEF info, it is usually present in tag.data
        // We stringify whatever data is available.

        setState(() {
          _tagInfo = info.isNotEmpty ? info : 'Tag détecté (détails indisponibles)';
          _status = 'Tag détecté';
        });

          // stop session (no errorMessage parameter in some versions)
        await NfcManager.instance.stopSession();
        setState(() => _isSessionStarted = false);
      },
        // Use default polling options as a set
        pollingOptions: {
          NfcPollingOption.iso14443,
          NfcPollingOption.iso15693,
          NfcPollingOption.iso18092,
        },
    );
  }

  void _stopSession() async {
    await NfcManager.instance.stopSession();
    setState(() {
      _status = 'Session arrêtée';
      _isSessionStarted = false;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('NFC Manager Demo')),
      body: Padding(
        padding: const EdgeInsets.all(16.0),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: [
            Text('Status: $_status'),
            const SizedBox(height: 12),
            Expanded(
              child: SingleChildScrollView(
                child: Text(_tagInfo.isEmpty ? 'Aucun tag lu pour le moment.' : _tagInfo),
              ),
            ),
            const SizedBox(height: 12),
            Row(
              children: [
                Expanded(
                  child: ElevatedButton(
                    onPressed: _isSessionStarted ? null : _startSession,
                    child: const Text('Démarrer session NFC'),
                  ),
                ),
                const SizedBox(width: 12),
                Expanded(
                  child: ElevatedButton(
                    onPressed: _isSessionStarted ? _stopSession : null,
                    style: ElevatedButton.styleFrom(backgroundColor: Colors.red),
                    child: const Text('Arrêter'),
                  ),
                ),
              ],
            ),
            const SizedBox(height: 8),
            Text('Remarques:\n- Testez sur un appareil réel avec NFC activé.\n- L\'émulateur Android ne prend généralement pas en charge le NFC.'),
          ],
        ),
      ),
    );
  }
}