import 'dart:convert';

import '../../services/settings_service.dart';
import '../models/watch_session.dart';

class RecentRoom {
  final String code;
  final String? name;
  final DateTime lastUsed;
  final ControlMode? controlMode;

  const RecentRoom({required this.code, this.name, required this.lastUsed, this.controlMode});

  Map<String, dynamic> toJson() => {
    'code': code,
    if (name != null) 'name': name,
    'lastUsed': lastUsed.millisecondsSinceEpoch,
    if (controlMode != null) 'controlMode': controlMode!.index,
  };

  factory RecentRoom.fromJson(Map<String, dynamic> json) {
    final modeIndex = json['controlMode'] as int?;
    return RecentRoom(
      code: json['code'] as String,
      name: json['name'] as String?,
      lastUsed: DateTime.fromMillisecondsSinceEpoch(json['lastUsed'] as int),
      controlMode: modeIndex != null ? ControlMode.values[modeIndex] : null,
    );
  }

  RecentRoom copyWith({
    String? code,
    String? name,
    DateTime? lastUsed,
    ControlMode? controlMode,
    bool clearName = false,
  }) => RecentRoom(
    code: code ?? this.code,
    name: clearName ? null : (name ?? this.name),
    lastUsed: lastUsed ?? this.lastUsed,
    controlMode: controlMode ?? this.controlMode,
  );
}

class RecentRoomsService {
  static const int _maxRooms = 20;

  static List<RecentRoom> getRecentRooms() {
    final json = SettingsService.instanceOrNull?.getRecentRooms();
    if (json == null) return [];
    try {
      final list = jsonDecode(json) as List<dynamic>;
      final rooms = list.map((e) => RecentRoom.fromJson(e as Map<String, dynamic>)).toList();
      rooms.sort((a, b) => b.lastUsed.compareTo(a.lastUsed));
      return rooms;
    } catch (_) {
      return [];
    }
  }

  static Future<void> _save(List<RecentRoom> rooms) async {
    rooms.sort((a, b) => b.lastUsed.compareTo(a.lastUsed));
    if (rooms.length > _maxRooms) rooms.removeRange(_maxRooms, rooms.length);
    await SettingsService.instanceOrNull?.setRecentRooms(jsonEncode(rooms.map((r) => r.toJson()).toList()));
  }

  static Future<void> addOrUpdateRoom(String code, {String? name, ControlMode? controlMode}) async {
    final rooms = getRecentRooms();
    final index = rooms.indexWhere((r) => r.code == code);
    if (index >= 0) {
      rooms[index] = rooms[index].copyWith(
        lastUsed: DateTime.now(),
        name: name ?? rooms[index].name,
        controlMode: controlMode,
      );
    } else {
      rooms.add(RecentRoom(code: code, name: name, lastUsed: DateTime.now(), controlMode: controlMode));
    }
    await _save(rooms);
  }

  static Future<void> removeRoom(String code) async {
    final rooms = getRecentRooms();
    rooms.removeWhere((r) => r.code == code);
    await _save(rooms);
  }

  static Future<void> renameRoom(String code, String? name) async {
    final rooms = getRecentRooms();
    final index = rooms.indexWhere((r) => r.code == code);
    if (index >= 0) {
      rooms[index] = rooms[index].copyWith(name: name, clearName: name == null);
      await _save(rooms);
    }
  }
}