handled saving and restoring fixed time alarms

lib/pages/task_edit_page.dart

@@ -2,9 +2,13 @@ import 'package:flutter/material.dart';
 
 import '../app_theme.dart';
 import '../model/alarm/alarm.dart';
+import '../model/alarm/fixed_time_alarm.dart';
+import '../model/alarm/location_alarm.dart';
+import '../model/alarm/relative_time_alarm.dart';
 import '../model/requests/create_alarm_request.dart';
 import '../model/requests/create_fixed_time_alarm_request.dart';
 import '../model/requests/create_location_alarm_request.dart';
+import '../model/requests/create_relative_time_alarm_request.dart';
 import '../model/requests/create_task_request.dart';
 import '../model/extensions/controller_context.dart';
 import '../model/task.dart';
@@ -37,7 +41,7 @@ class _TaskEditPageState extends State<TaskEditPage> {
   final formKey = GlobalKey<FormState>(debugLabel: 'taskEditFormKey');
   bool didFormChange = false;
   bool isDueTimeEnabled = false;
-  final List<CreateAlarmRequest> alarms = [];
+  final List<CreateAlarmRequest> alarmRequests = [];
 
   @override
   void didChangeDependencies() {
@@ -56,6 +60,18 @@ class _TaskEditPageState extends State<TaskEditPage> {
         isDueTimeEnabled = true;
       }
       isInitialized = true;
+      alarmRequests.addAll(
+        task!.alarms.map((alarm) {
+          if (alarm is FixedTimeAlarm) {
+            return CreateFixedTimeAlarmRequest.fromAlarm(alarm);
+          } else if (alarm is RelativeTimeAlarm) {
+            return CreateRelativeTimeAlarmRequest.fromAlarm(alarm);
+          } else if (alarm is LocationAlarm) {
+            return CreateLocationAlarmRequest.fromAlarm(alarm);
+          }
+          throw TypeError();
+        }),
+      );
       pageTitle = task!.title;
     }
   }
@@ -151,12 +167,12 @@ class _TaskEditPageState extends State<TaskEditPage> {
                       label: Text('Location'),
                       icon: Icon(Icons.location_on),
                     ),
-                    for (final (index, alarm) in alarms.indexed)
+                    for (final (index, alarmRequest) in alarmRequests.indexed)
                       AlarmForm(
-                        request: alarm,
+                        request: alarmRequest,
                         onChanged: (updated) {
                           setState(() {
-                            alarms[index] = updated;
+                            alarmRequests[index] = updated;
                           });
                         },
                       ),
@@ -187,7 +203,18 @@ class _TaskEditPageState extends State<TaskEditPage> {
         category: categoryController.text,
         subtasks: [],
         url: urlController.text,
-        alarms: [],
+        alarms: alarmRequests.map<Alarm>((e) {
+          if (e is CreateFixedTimeAlarmRequest) {
+            return e.toAlarm(generateId());
+          }
+          if (e is CreateRelativeTimeAlarmRequest) {
+            return e.toAlarm(generateId());
+          }
+          if (e is LocationAlarm) {
+            return e.toAlarm(generateId());
+          }
+          throw TypeError();
+        }).toList(),
       ),
     );
   }
@@ -223,12 +250,12 @@ class _TaskEditPageState extends State<TaskEditPage> {
   void onAddAlarmPressed(AlarmType alarmType) {
     switch (alarmType) {
       case AlarmType.location:
-        alarms.add(CreateLocationAlarmRequest());
+        alarmRequests.add(CreateLocationAlarmRequest());
       case AlarmType.timeFixed:
-        alarms.add(CreateFixedTimeAlarmRequest());
+        alarmRequests.add(CreateFixedTimeAlarmRequest());
 
       case AlarmType.timeRelative:
-        alarms.add(CreateFixedTimeAlarmRequest());
+        alarmRequests.add(CreateFixedTimeAlarmRequest());
     }
     setState(() {});
   }

lib/widgets/alarm_widgets/fixed_time_alarm_form.dart

@@ -26,11 +26,19 @@ class _FixedTimeAlarmFormState extends State<FixedTimeAlarmForm> {
   bool isDueTimeEnabled = false;
 
   @override
-  void initState() {
+  void didChangeDependencies() {
+    if (widget.request.triggerAt != null) {
+      dueDateController.text = getIsoDateString(widget.request.triggerAt!);
+      dueTimeController.text = TimeOfDay.fromDateTime(
+        widget.request.triggerAt!,
+      ).format(context);
+      isDueTimeEnabled = true;
+    }
+
     dueDateController.addListener(onDueDateChanged);
     dueTimeController.addListener(onDueTimeChanged);
 
-    super.initState();
+    super.didChangeDependencies();
   }
 
   @override