refactored project structure

lib/model/alarm/alarm.dart

@@ -0,0 +1,37 @@
+import 'fixed_time_alarm.dart';
+import 'location_alarm.dart';
+import 'relative_time_alarm.dart';
+
+abstract class Alarm {
+  String get id;
+  String get taskId;
+  AlarmType get alarmType;
+  Map<String, dynamic> toJson();
+
+  factory Alarm.fromJson(Map<String, dynamic> json) {
+    if (json.containsKey('alarmType')) {
+      switch (json['alarmType'] as String) {
+        case 'timeFixed':
+          return FixedTimeAlarm.fromJson(json);
+        case 'timeRelative':
+          return RelativeTimeAlarm.fromJson(json);
+        case 'location':
+          return LocationAlarm.fromJson(json);
+      }
+    }
+
+    throw ArgumentError('Unknown alarm type');
+  }
+
+  @override
+  bool operator ==(Object other) {
+    if (other is! Alarm) return false;
+
+    return hashCode == other.hashCode;
+  }
+
+  @override
+  int get hashCode => taskId.hashCode;
+}
+
+enum AlarmType { timeFixed, timeRelative, location }

lib/model/alarm/fixed_time_alarm.dart

@@ -0,0 +1,38 @@
+import 'alarm.dart';
+
+class FixedTimeAlarm implements Alarm {
+  @override
+  final String id;
+
+  @override
+  final String taskId;
+
+  final DateTime triggerAt;
+
+  @override
+  final AlarmType alarmType;
+
+  const FixedTimeAlarm({
+    required this.id,
+    required this.taskId,
+    required this.triggerAt,
+  }) : alarmType = AlarmType.timeFixed;
+
+  factory FixedTimeAlarm.fromJson(Map<String, dynamic> json) {
+    return FixedTimeAlarm(
+      id: json['id'] as String,
+      taskId: json['taskId'] as String,
+      triggerAt: DateTime.parse(json['triggerAt'] as String),
+    );
+  }
+
+  @override
+  Map<String, dynamic> toJson() {
+    return {
+      'id': id,
+      'taskId': taskId,
+      'triggerAt': triggerAt.toIso8601String(),
+      'alarmType': alarmType,
+    };
+  }
+}

lib/model/alarm/location_alarm.dart

@@ -0,0 +1,44 @@
+import 'alarm.dart';
+import '../location.dart';
+
+class LocationAlarm implements Alarm {
+  @override
+  final String id;
+
+  @override
+  final String taskId;
+
+  final Location location;
+
+  final int radiusMeters;
+
+  @override
+  final AlarmType alarmType;
+
+  const LocationAlarm({
+    required this.id,
+    required this.taskId,
+    required this.location,
+    required this.radiusMeters,
+  }) : alarmType = AlarmType.location;
+
+  factory LocationAlarm.fromJson(Map<String, dynamic> json) {
+    return LocationAlarm(
+      id: json['id'] as String,
+      taskId: json['taskId'] as String,
+      location: Location.fromJson(json['location'] as Map<String, dynamic>),
+      radiusMeters: json['radiusMeters'] as int,
+    );
+  }
+
+  @override
+  Map<String, dynamic> toJson() {
+    return {
+      'id': id,
+      'taskId': taskId,
+      'location': location.toJson(),
+      'radiusMeters': radiusMeters,
+      'alarmType': alarmType,
+    };
+  }
+}

lib/model/alarm/relative_time_alarm.dart

@@ -0,0 +1,38 @@
+import 'alarm.dart';
+
+class RelativeTimeAlarm implements Alarm {
+  @override
+  final String id;
+
+  @override
+  final String taskId;
+
+  final DateTime triggerAt;
+
+  @override
+  final AlarmType alarmType;
+
+  const RelativeTimeAlarm({
+    required this.id,
+    required this.taskId,
+    required this.triggerAt,
+  }) : alarmType = AlarmType.timeRelative;
+
+  factory RelativeTimeAlarm.fromJson(Map<String, dynamic> json) {
+    return RelativeTimeAlarm(
+      id: json['id'] as String,
+      taskId: json['taskId'] as String,
+      triggerAt: DateTime.parse(json['triggerAt'] as String),
+    );
+  }
+
+  @override
+  Map<String, dynamic> toJson() {
+    return {
+      'id': id,
+      'taskId': taskId,
+      'triggerAt': triggerAt.toIso8601String(),
+      'alarmType': alarmType,
+    };
+  }
+}