fluffychat/lib/utils/database/flutter_famedly_sdk_hive_database.dart

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

import 'package:matrix/matrix.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter/services.dart';
import 'package:flutter_secure_storage/flutter_secure_storage.dart';
import 'package:hive/hive.dart';
import 'package:hive_flutter/hive_flutter.dart';
import 'package:path_provider/path_provider.dart';

class FlutterFamedlySdkHiveDatabase extends FamedlySdkHiveDatabase {
  FlutterFamedlySdkHiveDatabase(String name, {HiveCipher encryptionCipher})
      : super(
          name,
          encryptionCipher: encryptionCipher,
        );

  static bool _hiveInitialized = false;
  static const String _hiveCipherStorageKey = 'hive_encryption_key';

  static Future<FamedlySdkHiveDatabase> hiveDatabaseBuilder(
      Client client) async {
    if (!kIsWeb && !_hiveInitialized) {
      Logs().i('Init Hive database...');
      await Hive.initFlutter();
      _hiveInitialized = true;
    }
    HiveCipher hiverCipher;
    try {
      // Workaround for secure storage is calling Platform.operatingSystem on web
      if (kIsWeb) throw MissingPluginException();

      final secureStorage = const FlutterSecureStorage();
      final containsEncryptionKey =
          await secureStorage.containsKey(key: _hiveCipherStorageKey);
      if (!containsEncryptionKey) {
        final key = Hive.generateSecureKey();
        await secureStorage.write(
          key: _hiveCipherStorageKey,
          value: base64UrlEncode(key),
        );
      }

      final encryptionKey = base64Url.decode(
        await secureStorage.read(key: _hiveCipherStorageKey),
      );
      hiverCipher = HiveAesCipher(encryptionKey);
    } on MissingPluginException catch (_) {
      Logs().i('Hive encryption is not supported on this platform');
    }
    final db = FamedlySdkHiveDatabase(
      client.clientName,
      encryptionCipher: hiverCipher,
    );
    Logs().i('Open Hive database...');
    await db.open();
    Logs().i('Hive database is ready!');
    return db;
  }

  @override
  int get maxFileSize => supportsFileStoring ? 100 * 1024 * 1024 : 0;
  @override
  bool get supportsFileStoring =>
      !kIsWeb && (Platform.isIOS || Platform.isAndroid);

  Future<String> _getFileStoreDirectory() async {
    try {
      return (await getApplicationDocumentsDirectory()).path;
    } on MissingPlatformDirectoryException catch (_) {
      return (await getDownloadsDirectory()).path;
    }
  }

  @override
  Future<Uint8List> getFile(String mxcUri) async {
    if (!supportsFileStoring) return null;
    final tempDirectory = await _getFileStoreDirectory();
    final file = File('$tempDirectory/$mxcUri');
    if (await file.exists() == false) return null;
    final bytes = await file.readAsBytes();
    return bytes;
  }

  @override
  Future storeFile(String mxcUri, Uint8List bytes, int time) async {
    if (!supportsFileStoring) return null;
    final tempDirectory = await _getFileStoreDirectory();
    final file = File('$tempDirectory/$mxcUri');
    if (await file.exists()) return;
    await file.writeAsBytes(bytes);
    return;
  }

  @override
  Future<void> clear(int clientId) async {
    await super.clear(clientId);
  }
}