import 'package:friendly_map/modules/platform/platform.dart';
import 'package:friendly_map/modules/storage/storage.dart';

import 'change_bus.dart';
import 'friend_service.dart' show hideAllKey;

/// 설정과 별도 저장(보관) 관리.
class SettingsService {
  SettingsService(this._storage, this._clock, DeviceStorageProbe probe, this._bus)
      : _archive = ArchiveService(
          messages: _storage.messages,
          settings: _storage.settings,
          clock: _clock,
          probe: probe,
        );

  final Storage _storage;
  final Clock _clock;
  final ArchiveService _archive;
  final ChangeBus _bus;

  Future<AppSettings> load() => _storage.settings.load();

  Future<void> save(AppSettings s) async {
    await _storage.settings.save(s, _clock.now());
    _bus.notify();
  }

  /// 값 하나만 바꾼다.
  Future<AppSettings> update({
    int? separateTextBytes,
    int? storageUsagePercent,
    String? exchangeMode,
    int? recoveryShares,
    int? recoveryThreshold,
  }) async {
    final s = await load();
    var shares = recoveryShares ?? s.recoveryShares;
    var need = recoveryThreshold ?? s.recoveryThreshold;
    shares = shares.clamp(2, 9);
    need = need.clamp(2, shares);
    final next = AppSettings(
      separateTextBytes: (separateTextBytes ?? s.separateTextBytes).clamp(64 * 1024, 512 * 1024 * 1024),
      storageUsagePercent: (storageUsagePercent ?? s.storageUsagePercent).clamp(50, 95),
      exchangeMode: exchangeMode ?? s.exchangeMode,
      recoveryShares: shares,
      recoveryThreshold: need,
    );
    await save(next);
    return next;
  }

  /// "모든 정보 숨기기": 켜면 모르는 사람의 친구 요청을 받지 않는다.
  Future<bool> hideAll() async => (await _storage.settings.getText(hideAllKey)) == 'true';

  Future<void> setHideAll(bool value) async {
    await _storage.settings.putText(hideAllKey, value ? 'true' : 'false', _clock.now());
    _bus.notify();
  }

  /// 이 방을 별도 저장으로 나누라고 권할 만한지.
  Future<ArchiveAdvice> adviseRoom(String roomId) => _archive.adviseRoom(roomId);

  /// 별도 저장으로 나눌 수 있는 범위 (처음~끝). 대화가 없으면 null.
  Future<(int, int)?> selectableSpan(String roomId) => _archive.selectableSpan(roomId);

  Future<int> archiveRange(String roomId, int from, int to) async {
    final n = await _archive.archiveRange(roomId, from, to);
    _bus.notify();
    return n;
  }

  Future<int> restoreRange(String roomId, int from, int to) async {
    final n = await _archive.restoreRange(roomId, from, to);
    _bus.notify();
    return n;
  }
}