import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:firebase_core/firebase_core.dart';
import 'package:http/http.dart' as http;
import '../auth/auth_service.dart';
import '../sync/r2_upload_service.dart';

abstract class CloudAccountCleanup {
  Future<void> deleteCloudData();
}

class AccountCloudCleanupService implements CloudAccountCleanup {
  final AuthService _auth;
  final FirebaseFirestore? _firestore;
  final http.Client _client;
  final String _workerUrl;

  AccountCloudCleanupService({
    required this._auth,
    FirebaseFirestore? firestore,
    http.Client? client,
    String? workerUrl,
  })  : _firestore = firestore ?? _resolveFirestore(),
        _client = client ?? http.Client(),
        _workerUrl = (workerUrl ?? R2UploadService.defaultWorkerUrl).replaceAll(RegExp(r'/+$'), '');

  static FirebaseFirestore? _resolveFirestore() {
    try {
      if (Firebase.apps.isNotEmpty) return FirebaseFirestore.instance;
    } catch (_) {}
    return null;
  }

  @override
  Future<void> deleteCloudData() async {
    final user = _auth.currentUser;
    if (user == null || user.isAnonymous) throw StateError('A permanent account is required.');
    final token = await _auth.getIdToken(true);
    if (token == null || token.isEmpty) throw StateError('A valid account session is required.');

    final response = await _client.delete(
      Uri.parse('$_workerUrl/account/cloud-data'),
      headers: {'Authorization': 'Bearer ${token.trim()}'},
    ).timeout(const Duration(seconds: 30));
    if (response.statusCode < 200 || response.statusCode >= 300) {
      throw StateError('MotorCloud cleanup was not completed (${response.statusCode}).');
    }

    final firestore = _firestore;
    if (firestore == null) throw StateError('MotorCloud database is unavailable.');
    final userRef = firestore.collection('users').doc(user.uid);
    final rides = await userRef.collection('rides').get();
    final motorcycles = await userRef.collection('motorcycles').get();
    final batch = firestore.batch();
    for (final doc in rides.docs) {
      batch.delete(doc.reference);
    }
    for (final doc in motorcycles.docs) {
      batch.delete(doc.reference);
    }
    batch.delete(userRef);
    await batch.commit();
  }
}