peyawallet/lib/services/wallet_cache_recovery.dart

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

import 'package:logger/logger.dart';

import 'app_paths.dart';

class WalletCacheRecovery {
  WalletCacheRecovery({required Logger logger}) : _logger = logger;

  final Logger _logger;

  Future<void> markOpenAttempt(String walletPath) async {
    final marker = await _markerFile();
    final payload = jsonEncode({
      'path': walletPath,
      'timestamp': DateTime.now().toIso8601String(),
    });
    await marker.writeAsString(payload);
  }

  Future<void> clearOpenAttempt() async {
    for (final marker in await _markerFiles()) {
      if (await marker.exists()) {
        await marker.delete();
      }
    }
  }

  Future<bool> recoverIfNeeded(String walletPath) async {
    for (final marker in await _markerFiles()) {
      if (!await marker.exists()) {
        continue;
      }
      final pendingPath = await _readPendingPath(marker);
      if (pendingPath == null || pendingPath != walletPath) {
        continue;
      }
      final recovered = await _rebuildCache(walletPath);
      await clearOpenAttempt();
      return recovered;
    }
    return false;
  }

  Future<File> _markerFile() async {
    return AppPaths.walletOpenMarkerFile();
  }

  Future<List<File>> _markerFiles() async {
    final files = <File>[await _markerFile()];
    files.addAll(await AppPaths.legacyWalletOpenMarkerFiles());
    return files;
  }

  Future<String?> _readPendingPath(File marker) async {
    try {
      final raw = await marker.readAsString();
      final json = jsonDecode(raw) as Map<String, dynamic>;
      final path = json['path'];
      return path is String ? path : null;
    } catch (error) {
      _logger.w('Failed to read wallet open marker: $error');
      return null;
    }
  }

  Future<bool> _rebuildCache(String walletPath) async {
    final walletFile = File(walletPath);
    final keysFile = File('$walletPath.keys');
    if (!await walletFile.exists()) {
      return false;
    }
    if (!await keysFile.exists()) {
      _logger.w('Wallet keys not found for recovery: $walletPath');
      return false;
    }
    final backupPath =
        '${walletFile.path}.cache.bak.${DateTime.now().millisecondsSinceEpoch}';
    await walletFile.rename(backupPath);
    _logger.w('Wallet cache moved to $backupPath');
    return true;
  }
}