import 'package:riverpod_annotation/riverpod_annotation.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:worldhopper/helpers/eink_detection_helper.dart';

part 'eink_mode_provider.g.dart';

/// Key for storing e-ink mode preference in SharedPreferences
const String _einkModeKey = 'eink_mode';

/// Provider for e-ink mode state management.
///
/// On first launch (no stored preference), auto-detects whether the device is
/// a known e-ink device and persists the result. Subsequent launches use the
/// stored value so the user's explicit choice is always respected.
@riverpod
class EinkModeNotifier extends _$EinkModeNotifier {
  @override
  bool build() {
    _loadEinkMode();
    return false; // Default value until loaded
  }

  /// Load e-ink mode from SharedPreferences, auto-detecting on first launch.
  Future<void> _loadEinkMode() async {
    final prefs = await SharedPreferences.getInstance();
    final stored = prefs.getBool(_einkModeKey);

    if (stored != null) {
      state = stored;
    } else {
      // First launch — auto-detect
      final detected = await EinkDetectionHelper.isEinkDevice();
      state = detected;
      await prefs.setBool(_einkModeKey, detected);
    }
  }

  /// Set e-ink mode and persist to SharedPreferences.
  Future<void> setEinkMode(bool enabled) async {
    state = enabled;
    final prefs = await SharedPreferences.getInstance();
    await prefs.setBool(_einkModeKey, enabled);
  }
}