/// Settings Provider
library;

import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:path_provider/path_provider.dart';
import 'dart:io';

import '../../../domain/entities/user.dart';
import '../../../infrastructure/datasources/remote/auth_api_service.dart';

/// Audio Quality enum
enum AudioQuality { low, medium, high, lossless }

/// Settings state
class SettingsState {
  final User? user;
  final AudioQuality audioQuality;
  final bool downloadOnMobileData;
  final bool showExplicitContent;
  final bool crossfadeEnabled;
  final double crossfadeDuration;
  final bool gaplessPlayback;
  final bool normalizeVolume;
  final String cacheSize;
  final bool isLoading;
  final String? error;

  const SettingsState({
    this.user,
    this.audioQuality = AudioQuality.high,
    this.downloadOnMobileData = false,
    this.showExplicitContent = true,
    this.crossfadeEnabled = false,
    this.crossfadeDuration = 5.0,
    this.gaplessPlayback = true,
    this.normalizeVolume = false,
    this.cacheSize = '0 MB',
    this.isLoading = false,
    this.error,
  });

  SettingsState copyWith({
    User? user,
    AudioQuality? audioQuality,
    bool? downloadOnMobileData,
    bool? showExplicitContent,
    bool? crossfadeEnabled,
    double? crossfadeDuration,
    bool? gaplessPlayback,
    bool? normalizeVolume,
    String? cacheSize,
    bool? isLoading,
    String? error,
  }) {
    return SettingsState(
      user: user ?? this.user,
      audioQuality: audioQuality ?? this.audioQuality,
      downloadOnMobileData: downloadOnMobileData ?? this.downloadOnMobileData,
      showExplicitContent: showExplicitContent ?? this.showExplicitContent,
      crossfadeEnabled: crossfadeEnabled ?? this.crossfadeEnabled,
      crossfadeDuration: crossfadeDuration ?? this.crossfadeDuration,
      gaplessPlayback: gaplessPlayback ?? this.gaplessPlayback,
      normalizeVolume: normalizeVolume ?? this.normalizeVolume,
      cacheSize: cacheSize ?? this.cacheSize,
      isLoading: isLoading ?? this.isLoading,
      error: error,
    );
  }
}

/// Settings notifier
class SettingsNotifier extends StateNotifier<SettingsState> {
  SettingsNotifier(this._authApiService) : super(const SettingsState()) {
    _loadSettingsFromPrefs();
  }

  final AuthApiService _authApiService;
  SharedPreferences? _prefs;

  // Keys for shared preferences
  static const String _audioQualityKey = 'audio_quality';
  static const String _downloadOnMobileDataKey = 'download_on_mobile_data';
  static const String _showExplicitContentKey = 'show_explicit_content';
  static const String _crossfadeEnabledKey = 'crossfade_enabled';
  static const String _crossfadeDurationKey = 'crossfade_duration';
  static const String _gaplessPlaybackKey = 'gapless_playback';
  static const String _normalizeVolumeKey = 'normalize_volume';

  /// Initialize shared preferences and load settings
  Future<void> _loadSettingsFromPrefs() async {
    _prefs = await SharedPreferences.getInstance();

    final audioQualityIndex = _prefs?.getInt(_audioQualityKey) ?? 2;
    final downloadOnMobileData = _prefs?.getBool(_downloadOnMobileDataKey) ?? false;
    final showExplicitContent = _prefs?.getBool(_showExplicitContentKey) ?? true;
    final crossfadeEnabled = _prefs?.getBool(_crossfadeEnabledKey) ?? false;
    final crossfadeDuration = _prefs?.getDouble(_crossfadeDurationKey) ?? 5.0;
    final gaplessPlayback = _prefs?.getBool(_gaplessPlaybackKey) ?? true;
    final normalizeVolume = _prefs?.getBool(_normalizeVolumeKey) ?? false;

    state = state.copyWith(
      audioQuality: AudioQuality.values[audioQualityIndex],
      downloadOnMobileData: downloadOnMobileData,
      showExplicitContent: showExplicitContent,
      crossfadeEnabled: crossfadeEnabled,
      crossfadeDuration: crossfadeDuration,
      gaplessPlayback: gaplessPlayback,
      normalizeVolume: normalizeVolume,
    );

    await _calculateCacheSize();
  }

  /// Load user profile from API
  Future<void> loadSettings() async {
    state = state.copyWith(isLoading: true, error: null);

    try {
      final user = await _authApiService.getCurrentUser();
      state = state.copyWith(user: user, isLoading: false);
    } catch (e) {
      state = state.copyWith(
        error: e.toString(),
        isLoading: false,
      );
    }
  }

  /// Update user profile
  Future<void> updateProfile({
    String? displayName,
    String? avatarUrl,
  }) async {
    state = state.copyWith(isLoading: true, error: null);

    try {
      final updatedUser = await _authApiService.updateProfile(
        displayName: displayName,
        avatarUrl: avatarUrl,
      );

      state = state.copyWith(
        user: updatedUser,
        isLoading: false,
      );
    } catch (e) {
      state = state.copyWith(
        error: e.toString(),
        isLoading: false,
      );
      rethrow;
    }
  }

  /// Set audio quality
  Future<void> setAudioQuality(AudioQuality quality) async {
    await _prefs?.setInt(_audioQualityKey, quality.index);
    state = state.copyWith(audioQuality: quality);
  }

  /// Toggle download on mobile data
  Future<void> toggleDownloadOnMobileData(bool value) async {
    await _prefs?.setBool(_downloadOnMobileDataKey, value);
    state = state.copyWith(downloadOnMobileData: value);
  }

  /// Toggle explicit content
  Future<void> toggleShowExplicitContent(bool value) async {
    await _prefs?.setBool(_showExplicitContentKey, value);
    state = state.copyWith(showExplicitContent: value);
  }

  /// Toggle crossfade
  Future<void> toggleCrossfade(bool value) async {
    await _prefs?.setBool(_crossfadeEnabledKey, value);
    state = state.copyWith(crossfadeEnabled: value);
  }

  /// Set crossfade duration
  Future<void> setCrossfadeDuration(double duration) async {
    await _prefs?.setDouble(_crossfadeDurationKey, duration);
    state = state.copyWith(crossfadeDuration: duration);
  }

  /// Toggle gapless playback
  Future<void> toggleGaplessPlayback(bool value) async {
    await _prefs?.setBool(_gaplessPlaybackKey, value);
    state = state.copyWith(gaplessPlayback: value);
  }

  /// Toggle normalize volume
  Future<void> toggleNormalizeVolume(bool value) async {
    await _prefs?.setBool(_normalizeVolumeKey, value);
    state = state.copyWith(normalizeVolume: value);
  }

  /// Calculate cache size
  Future<void> _calculateCacheSize() async {
    try {
      final tempDir = await getTemporaryDirectory();
      final appDocDir = await getApplicationDocumentsDirectory();

      final tempSize = _getFolderSize(tempDir);
      final docSize = _getFolderSize(appDocDir);

      final totalSize = tempSize + docSize;
      final cacheSizeStr = _formatBytes(totalSize);

      state = state.copyWith(cacheSize: cacheSizeStr);
    } catch (e) {
      state = state.copyWith(cacheSize: 'Unknown');
    }
  }

  /// Get folder size in bytes
  int _getFolderSize(Directory dir) {
    int size = 0;
    try {
      if (dir.existsSync()) {
        dir
            .listSync(recursive: true, followLinks: false)
            .forEach((FileSystemEntity entity) {
          if (entity is File) {
            size += entity.lengthSync();
          }
        });
      }
    } catch (e) {
      // Ignore errors
    }
    return size;
  }

  /// Format bytes to human readable string
  String _formatBytes(int bytes) {
    if (bytes < 1024) return '$bytes B';
    if (bytes < 1024 * 1024) return '${(bytes / 1024).toStringAsFixed(1)} KB';
    if (bytes < 1024 * 1024 * 1024) {
      return '${(bytes / (1024 * 1024)).toStringAsFixed(1)} MB';
    }
    return '${(bytes / (1024 * 1024 * 1024)).toStringAsFixed(1)} GB';
  }

  /// Clear cache
  Future<void> clearCache() async {
    state = state.copyWith(isLoading: true);

    try {
      final tempDir = await getTemporaryDirectory();
      if (await tempDir.exists()) {
        await _deleteFolderContents(tempDir);
      }

      await _calculateCacheSize();
      state = state.copyWith(isLoading: false);
    } catch (e) {
      state = state.copyWith(
        error: e.toString(),
        isLoading: false,
      );
      rethrow;
    }
  }

  /// Delete folder contents
  Future<void> _deleteFolderContents(Directory dir) async {
    try {
      if (await dir.exists()) {
        await for (final entity in dir.list()) {
          if (entity is File) {
            await entity.delete();
          } else if (entity is Directory) {
            await entity.delete(recursive: true);
          }
        }
      }
    } catch (e) {
      // Ignore errors
    }
  }
}

/// Settings provider
final settingsProvider = StateNotifierProvider<SettingsNotifier, SettingsState>(
  (ref) {
    final authApiService = ref.watch(authApiServiceProvider);
    return SettingsNotifier(authApiService);
  },
);