flutter-template/lib/core/theme/theme_notifier.dart

import 'dart:async';

import 'package:flutter/material.dart';
import 'package:sunny_mochi/core/theme/app_colors.dart';
import 'package:riverpod_annotation/riverpod_annotation.dart';
import 'package:shared_preferences/shared_preferences.dart';

part 'theme_notifier.g.dart';

/// 当前色板 Notifier — 对应 iOS AppThemeManager。
///
/// **默认 white**（白色导航栏 + 中性灰背景，对应设计稿默认配色）。
/// 切换持久化到 SharedPreferences，下次启动恢复。
@Riverpod(keepAlive: true)
class ThemeNotifier extends _$ThemeNotifier {
  static const _keyScheme = 'color_scheme';

  @override
  AppColorScheme build() {
    unawaited(_restore());
    return AppColorScheme.white;
  }

  /// 切换主题色板（同时持久化）
  void switchScheme(AppColorScheme scheme) {
    state = scheme;
    unawaited(
      SharedPreferences.getInstance().then(
        (prefs) => prefs.setString(_keyScheme, scheme.name),
      ),
    );
  }

  Future<void> _restore() async {
    final prefs = await SharedPreferences.getInstance();
    final name = prefs.getString(_keyScheme);
    if (name != null) {
      state = AppColorScheme.values.firstWhere(
        (e) => e.name == name,
        orElse: () => AppColorScheme.white,
      );
    }
  }
}

/// 明亮 / 暗色 / 跟随系统 模式（与 iOS UIInterfaceStyle 对齐）
@Riverpod(keepAlive: true)
class ThemeModeNotifier extends _$ThemeModeNotifier {
  static const _keyMode = 'theme_mode';

  @override
  ThemeMode build() {
    unawaited(_restore());
    return ThemeMode.light;
  }

  void switchMode(ThemeMode mode) {
    state = mode;
    unawaited(
      SharedPreferences.getInstance().then(
        (prefs) => prefs.setString(_keyMode, mode.name),
      ),
    );
  }

  Future<void> _restore() async {
    final prefs = await SharedPreferences.getInstance();
    final name = prefs.getString(_keyMode);
    if (name != null) {
      state = ThemeMode.values.firstWhere(
        (e) => e.name == name,
        orElse: () => ThemeMode.light,
      );
    }
  }
}