Flutter App

flutter_app/lib/services/storage_service.dart

@@ -0,0 +1,54 @@
+import 'dart:convert';
+import 'package:shared_preferences/shared_preferences.dart';
+import '../models/price_data.dart';
+
+class StorageService {
+  static const String _alertsKey = 'price_alerts';
+  static const String _customAuecKey = 'custom_auec_amount';
+
+  Future<List<PriceAlert>> getAlerts() async {
+    final prefs = await SharedPreferences.getInstance();
+    final alertsJson = prefs.getString(_alertsKey);
+    if (alertsJson == null) return [];
+
+    final List<dynamic> decoded = jsonDecode(alertsJson);
+    return decoded.map((e) => PriceAlert.fromJson(e as Map<String, dynamic>)).toList();
+  }
+
+  Future<void> saveAlerts(List<PriceAlert> alerts) async {
+    final prefs = await SharedPreferences.getInstance();
+    final alertsJson = jsonEncode(alerts.map((e) => e.toJson()).toList());
+    await prefs.setString(_alertsKey, alertsJson);
+  }
+
+  Future<void> addAlert(PriceAlert alert) async {
+    final alerts = await getAlerts();
+    alerts.add(alert);
+    await saveAlerts(alerts);
+  }
+
+  Future<void> updateAlert(PriceAlert alert) async {
+    final alerts = await getAlerts();
+    final index = alerts.indexWhere((a) => a.id == alert.id);
+    if (index != -1) {
+      alerts[index] = alert;
+      await saveAlerts(alerts);
+    }
+  }
+
+  Future<void> deleteAlert(String id) async {
+    final alerts = await getAlerts();
+    alerts.removeWhere((a) => a.id == id);
+    await saveAlerts(alerts);
+  }
+
+  Future<double?> getCustomAuecAmount() async {
+    final prefs = await SharedPreferences.getInstance();
+    return prefs.getDouble(_customAuecKey);
+  }
+
+  Future<void> setCustomAuecAmount(double amount) async {
+    final prefs = await SharedPreferences.getInstance();
+    await prefs.setDouble(_customAuecKey, amount);
+  }
+}