update theme selection

lib/core/theme/theme_provider.dart

@@ -0,0 +1,88 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:riverpod_annotation/riverpod_annotation.dart';
+
+import 'package:worker/core/database/app_settings_box.dart';
+import 'package:worker/core/theme/colors.dart';
+
+part 'theme_provider.g.dart';
+
+/// Theme settings state
+class ThemeSettings {
+  const ThemeSettings({
+    required this.seedColorId,
+    required this.themeMode,
+  });
+
+  final String seedColorId;
+  final ThemeMode themeMode;
+
+  /// Get the actual Color from the seed color ID
+  Color get seedColor => AppColors.getSeedColorById(seedColorId);
+
+  /// Get the SeedColorOption from the ID
+  SeedColorOption get seedColorOption => AppColors.seedColorOptions.firstWhere(
+        (option) => option.id == seedColorId,
+        orElse: () => AppColors.seedColorOptions.first,
+      );
+
+  ThemeSettings copyWith({
+    String? seedColorId,
+    ThemeMode? themeMode,
+  }) {
+    return ThemeSettings(
+      seedColorId: seedColorId ?? this.seedColorId,
+      themeMode: themeMode ?? this.themeMode,
+    );
+  }
+}
+
+/// Provider for managing theme settings with Hive persistence
+/// Uses AppSettingsBox for storage
+@Riverpod(keepAlive: true)
+class ThemeSettingsNotifier extends _$ThemeSettingsNotifier {
+  @override
+  ThemeSettings build() {
+    return _loadFromSettings();
+  }
+
+  ThemeSettings _loadFromSettings() {
+    return ThemeSettings(
+      seedColorId: AppSettingsBox.getSeedColorId(),
+      themeMode: ThemeMode.values[AppSettingsBox.getThemeModeIndex()],
+    );
+  }
+
+  /// Update seed color
+  Future<void> setSeedColor(String colorId) async {
+    await AppSettingsBox.setSeedColorId(colorId);
+    state = state.copyWith(seedColorId: colorId);
+  }
+
+  /// Update theme mode (light/dark/system)
+  Future<void> setThemeMode(ThemeMode mode) async {
+    await AppSettingsBox.setThemeModeIndex(mode.index);
+    state = state.copyWith(themeMode: mode);
+  }
+
+  /// Toggle between light and dark mode
+  Future<void> toggleThemeMode() async {
+    final newMode =
+        state.themeMode == ThemeMode.light ? ThemeMode.dark : ThemeMode.light;
+    await setThemeMode(newMode);
+  }
+}
+
+/// Provider for the current seed color (convenience provider)
+@riverpod
+Color currentSeedColor(Ref ref) {
+  return ref.watch(
+    themeSettingsProvider.select((settings) => settings.seedColor),
+  );
+}
+
+/// Provider for available seed color options
+@riverpod
+List<SeedColorOption> seedColorOptions(Ref ref) {
+  return AppColors.seedColorOptions;
+}