import 'dart:convert';
import 'dart:io';

import 'package:http/http.dart' as http;
import 'package:open_filex/open_filex.dart';
import 'package:package_info_plus/package_info_plus.dart';
import 'package:path_provider/path_provider.dart';
import 'package:url_launcher/url_launcher.dart';

/// Détecte une version plus récente (`/version`) et l'installe **in-app** :
/// télécharge l'APK dans le stockage de l'app puis lance l'installeur système
/// (un seul tap « Installer »). Fallback navigateur si l'install directe échoue.
class UpdateService {
  UpdateService(this._baseUrl);
  final Future<String> _baseUrl;

  Future<UpdateInfo?> check() async {
    try {
      final base = await _baseUrl;
      final res = await http.get(Uri.parse('$base/version')).timeout(const Duration(seconds: 6));
      if (res.statusCode != 200) return null;
      final data = jsonDecode(res.body) as Map<String, dynamic>;
      final remote = data['version_code'] as int? ?? 0;
      final info = await PackageInfo.fromPlatform();
      final current = int.tryParse(info.buildNumber) ?? 0;
      if (remote > current) {
        return UpdateInfo(
          version: data['version'] as String? ?? '?',
          apkUrl: data['apk_url'] as String? ?? '$base/download/apk',
          notes: data['notes'] as String? ?? '',
        );
      }
    } catch (_) {/* pas de réseau / pas d'update → on ignore */}
    return null;
  }

  /// Télécharge l'APK puis lance l'installeur. `onProgress` : 0.0 → 1.0
  /// (ou null si la taille est inconnue). Renvoie true si l'installeur s'ouvre.
  Future<bool> apply(UpdateInfo info, {void Function(double?)? onProgress}) async {
    try {
      final dir = await getExternalStorageDirectory() ?? await getTemporaryDirectory();
      final file = File('${dir.path}/gamemanager-update.apk');

      final req = http.Request('GET', Uri.parse(info.apkUrl));
      final resp = await req.send().timeout(const Duration(seconds: 30));
      if (resp.statusCode != 200) return _fallback(info);

      final total = resp.contentLength ?? 0;
      var received = 0;
      final sink = file.openWrite();
      await for (final chunk in resp.stream) {
        sink.add(chunk);
        received += chunk.length;
        onProgress?.call(total > 0 ? received / total : null);
      }
      await sink.close();

      final result = await OpenFilex.open(
        file.path,
        type: 'application/vnd.android.package-archive',
      );
      if (result.type == ResultType.done) return true;
      return _fallback(info); // l'installeur n'a pas pris → navigateur
    } catch (_) {
      return _fallback(info);
    }
  }

  Future<bool> _fallback(UpdateInfo info) async {
    final uri = Uri.parse(info.apkUrl);
    if (!await canLaunchUrl(uri)) return false;
    return launchUrl(uri, mode: LaunchMode.externalApplication);
  }
}

class UpdateInfo {
  UpdateInfo({required this.version, required this.apkUrl, required this.notes});
  final String version;
  final String apkUrl;
  final String notes;
}