import 'dart:convert';

import 'package:shared_preferences/shared_preferences.dart';

class NotificationLogEntry {
  final int id;
  final String kind; // 'daily' | 'snooze'
  final String type; // 'single' | 'group'
  final int whenEpochMs; // exact scheduled time (epoch ms)
  final int createdAtEpochMs; // when we created the schedule (epoch ms)
  final String title;
  final String payload;
  final int? singleId; // supplement id for single
  final String? timeKey; // HH:mm for group

  const NotificationLogEntry({
    required this.id,
    required this.kind,
    required this.type,
    required this.whenEpochMs,
    required this.createdAtEpochMs,
    required this.title,
    required this.payload,
    this.singleId,
    this.timeKey,
  });

  Map<String, dynamic> toJson() => {
        'id': id,
        'kind': kind,
        'type': type,
        'when': whenEpochMs,
        'createdAt': createdAtEpochMs,
        'title': title,
        'payload': payload,
        'singleId': singleId,
        'timeKey': timeKey,
      };

  static NotificationLogEntry fromJson(Map<String, dynamic> map) {
    return NotificationLogEntry(
      id: map['id'] is int ? map['id'] as int : int.tryParse('${map['id']}') ?? 0,
      kind: map['kind'] ?? 'unknown',
      type: map['type'] ?? 'unknown',
      whenEpochMs: map['when'] is int ? map['when'] as int : int.tryParse('${map['when']}') ?? 0,
      createdAtEpochMs: map['createdAt'] is int ? map['createdAt'] as int : int.tryParse('${map['createdAt']}') ?? 0,
      title: map['title'] ?? '',
      payload: map['payload'] ?? '',
      singleId: map['singleId'],
      timeKey: map['timeKey'],
    );
  }
}

class NotificationDebugStore {
  NotificationDebugStore._internal();
  static final NotificationDebugStore instance = NotificationDebugStore._internal();

  static const String _prefsKey = 'notification_log';
  static const int _maxEntries = 200;

  Future<List<NotificationLogEntry>> getAll() async {
    final prefs = await SharedPreferences.getInstance();
    final raw = prefs.getString(_prefsKey);
    if (raw == null || raw.isEmpty) return [];
    try {
      final list = jsonDecode(raw) as List;
      return list
          .map((e) => NotificationLogEntry.fromJson(e as Map<String, dynamic>))
          .toList();
    } catch (_) {
      return [];
    }
  }

  Future<void> add(NotificationLogEntry entry) async {
    final prefs = await SharedPreferences.getInstance();
    final current = await getAll();
    current.add(entry);
    // Cap size
    final trimmed = current.length > _maxEntries
        ? current.sublist(current.length - _maxEntries)
        : current;
    final serialized = jsonEncode(trimmed.map((e) => e.toJson()).toList());
    await prefs.setString(_prefsKey, serialized);
  }

  Future<void> clear() async {
    final prefs = await SharedPreferences.getInstance();
    await prefs.remove(_prefsKey);
  }
}