import 'package:supabase_flutter/supabase_flutter.dart' as supabase;
import 'package:dio/dio.dart';
import 'package:shared_preferences/shared_preferences.dart';
import '../models/user_model.dart';
import '../core/api_config.dart';
import 'auth_service.dart';

/// Implementasi AuthService menggunakan Supabase
class SupabaseAuthService implements AuthService {
  final supabase.SupabaseClient _client = supabase.Supabase.instance.client;
  final Dio _dio = Dio();

  @override
  Future<UserModel> login(String email, String password) async {
    try {
      final response = await _client.auth.signInWithPassword(
        email: email,
        password: password,
      );
      
      final user = response.user;
      if (user == null) {
        throw Exception('Login gagal: User tidak ditemukan');
      }

      // Ambil device_id dari backend
      String? deviceId;
      try {
        final deviceRes = await _dio.get('${ApiConfig.baseUrl}/device/my-device/${user.id}');
        if (deviceRes.statusCode == 200) {
          deviceId = deviceRes.data['device_id'];
        }
      } catch (e) {
        print('Gagal mengambil info device: $e');
        // Tidak melempar error agar login tetap sukses meskipun belum ada device
      }

      // Simpan device_id ke cache lokal agar auto-login selanjutnya super cepat
      if (deviceId != null) {
        final prefs = await SharedPreferences.getInstance();
        await prefs.setString('cached_device_id', deviceId);
      }

      return UserModel(
        id: user.id,
        name: user.userMetadata?['name'] ?? user.email?.split('@').first ?? 'User',
        email: user.email ?? email,
        token: response.session?.accessToken ?? '',
        deviceId: deviceId,
      );
    } on supabase.AuthException catch (e) {
      if (e.message.contains('Invalid login credentials')) {
        throw Exception('Email atau password salah.');
      } else if (e.message.contains('Email not confirmed')) {
        throw Exception('Email belum diverifikasi.');
      }
      throw Exception(e.message);
    } catch (e) {
      throw Exception('Terjadi kesalahan koneksi atau server.');
    }
  }

  @override
  Future<UserModel> register(String name, String email, String password, String claimCode) async {
    try {
      final response = await _client.auth.signUp(
        email: email,
        password: password,
        data: {'name': name},
      );

      final user = response.user;
      if (user == null) {
        throw Exception('Registrasi gagal');
      }

      // Klaim device setelah berhasil mendaftar ke Supabase
      String? deviceId;
      try {
        final claimRes = await _dio.post('${ApiConfig.baseUrl}/device/claim', data: {
          'claim_code': claimCode,
          'user_id': user.id,
        });

        if (claimRes.statusCode == 200) {
          deviceId = claimRes.data['device']['device_id'];
          // Simpan device_id ke cache lokal
          final prefs = await SharedPreferences.getInstance();
          await prefs.setString('cached_device_id', deviceId!);
        }
      } catch (e) {
        // Jika gagal klaim
        String errorMsg = 'Gagal klaim perangkat.';
        if (e is DioException && e.response?.data != null) {
          errorMsg = e.response?.data['message'] ?? errorMsg;
        }
        throw Exception('Akun terbuat, tapi $errorMsg');
      }

      return UserModel(
        id: user.id,
        name: name,
        email: email,
        token: response.session?.accessToken ?? '',
        deviceId: deviceId,
      );
    } on supabase.AuthException catch (e) {
      if (e.message.contains('already registered')) {
        throw Exception('Email sudah terdaftar.');
      } else if (e.message.contains('weak')) {
        throw Exception('Password terlalu lemah.');
      }
      throw Exception(e.message);
    } catch (e) {
      throw Exception('Terjadi kesalahan koneksi atau server.');
    }
  }

  @override
  Future<void> logout() async {
    // Hapus sesi Supabase
    await _client.auth.signOut();
    
    // Hapus cache device_id agar tidak terbawa jika user login pakai akun lain
    final prefs = await SharedPreferences.getInstance();
    await prefs.remove('cached_device_id');
  }

  // Fungsi tambahan untuk memulihkan sesi
  Future<UserModel?> checkSession() async {
    final session = _client.auth.currentSession;
    if (session != null) {
      final user = session.user;
      
      // Ambil device_id langsung dari cache lokal (cepat & offline-safe)
      String? deviceId;
      try {
        final prefs = await SharedPreferences.getInstance();
        deviceId = prefs.getString('cached_device_id');
      } catch (e) {
        print('Gagal membaca cache device_id: $e');
      }

      return UserModel(
        id: user.id,
        name: user.userMetadata?['name'] ?? user.email?.split('@').first ?? 'User',
        email: user.email ?? '',
        token: session.accessToken,
        deviceId: deviceId,
      );
    }
    return null;
  }
}