implemented scheduled local notifications for reminders and tasks

lib/api/task_implementation.dart

@@ -31,6 +31,13 @@ class TaskAPIService extends APIService implements TaskService {
         .post('/tasks/${task.id}', body: task.toJSON())
         .then((map) => Task.fromJson(map));
   }
+  
+  @override
+  Future<List<Task>> getAll() {
+    return client
+        .get('/tasks/all')
+        .then((value) => value.map<Task>((taskJson) => Task.fromJson(taskJson)).toList());
+  }
 
   @override
   Future<List<Task>> getByOptions(TaskServiceOptions options) {

lib/global.dart

@@ -1,13 +1,20 @@
+//import 'dart:math';
+import 'dart:developer';
+
 import 'package:flutter/material.dart';
+import 'package:flutter_local_notifications/flutter_local_notifications.dart';
 import 'package:flutter_secure_storage/flutter_secure_storage.dart';
 import 'package:vikunja_app/api/client.dart';
 import 'package:vikunja_app/api/list_implementation.dart';
 import 'package:vikunja_app/api/namespace_implementation.dart';
 import 'package:vikunja_app/api/task_implementation.dart';
 import 'package:vikunja_app/api/user_implementation.dart';
+import 'package:vikunja_app/managers/notifications.dart';
 import 'package:vikunja_app/managers/user.dart';
 import 'package:vikunja_app/models/user.dart';
 import 'package:vikunja_app/service/services.dart';
+import 'package:timezone/data/latest_all.dart' as tz;
+import 'package:timezone/timezone.dart' as tz;
 
 class VikunjaGlobal extends StatefulWidget {
   final Widget child;
@@ -45,12 +52,21 @@ class VikunjaGlobalState extends State<VikunjaGlobal> {
 
   ListService get listService => new ListAPIService(client, _storage);
 
+  FlutterLocalNotificationsPlugin get notificationsPlugin => new FlutterLocalNotificationsPlugin();
+
   TaskServiceOptions get taskServiceOptions => new TaskServiceOptions();
 
+  NotificationClass get notifications => new NotificationClass();
+
+  NotificationAppLaunchDetails notifLaunch;
+
+
   @override
   void initState() {
     super.initState();
     _loadCurrentUser();
+    tz.initializeTimeZones();
+    notificationInitializer();
   }
 
   void changeUser(User newUser, {String token, String base}) async {
@@ -78,6 +94,27 @@ class VikunjaGlobalState extends State<VikunjaGlobal> {
     });
   }
 
+  void notificationInitializer() async {
+    notifLaunch = await notificationsPlugin.getNotificationAppLaunchDetails();
+    await notifications.initNotifications(notificationsPlugin);
+    requestIOSPermissions(notificationsPlugin);
+
+  }
+
+  void scheduleDueNotifications() {
+    notificationsPlugin.cancelAll().then((value) {
+      taskService.getAll().then((value) =>
+          value.forEach((task) {
+            if(task.reminders != null)
+              task.reminders.forEach((reminder) {
+                scheduleNotification("This is your reminder for '" + task.title + "'", task.description, notificationsPlugin, reminder);
+              });
+            scheduleNotification("The task '" + task.title + "' is due.", task.description, notificationsPlugin, task.due);
+          })
+      );
+    });
+  }
+
 
   void logoutUser(BuildContext context) {
     _storage.deleteAll().then((_) {
@@ -138,6 +175,9 @@ class VikunjaGlobalState extends State<VikunjaGlobal> {
     if (_loading) {
       return new Center(child: new CircularProgressIndicator());
     }
+    if(client != null) {
+      scheduleDueNotifications();
+    }
     return new _VikunjaGlobalInherited(
       data: this,
       child: client == null ? widget.login : widget.child,

lib/managers/notifications.dart

@@ -0,0 +1,81 @@
+// https://medium.com/@fuzzymemory/adding-scheduled-notifications-in-your-flutter-application-19be1f82ade8
+
+import 'dart:math';
+
+import 'package:flutter_native_timezone/flutter_native_timezone.dart';
+import 'package:timezone/data/latest_all.dart' as tz;
+import 'package:timezone/timezone.dart' as tz;
+
+import 'package:flutter_local_notifications/flutter_local_notifications.dart'as notifs;
+import 'package:rxdart/subjects.dart' as rxSub;
+
+class NotificationClass{
+  final int id;
+  final String title;
+  final String body;
+  final String payload;
+  NotificationClass({this.id, this.body, this.payload, this.title});
+
+  final rxSub.BehaviorSubject<NotificationClass> didReceiveLocalNotificationSubject =
+  rxSub.BehaviorSubject<NotificationClass>();
+  final rxSub.BehaviorSubject<String> selectNotificationSubject =
+  rxSub.BehaviorSubject<String>();
+
+  Future<void> initNotifications(notifs.FlutterLocalNotificationsPlugin notifsPlugin) async {
+    var initializationSettingsAndroid =
+    notifs.AndroidInitializationSettings('vikunja_logo');
+    var initializationSettingsIOS = notifs.IOSInitializationSettings(
+        requestAlertPermission: false,
+        requestBadgePermission: false,
+        requestSoundPermission: false,
+        onDidReceiveLocalNotification:
+            (int id, String title, String body, String payload) async {
+          didReceiveLocalNotificationSubject
+              .add(NotificationClass(id: id, title: title, body: body, payload: payload));
+        });
+    var initializationSettings = notifs.InitializationSettings(
+        android: initializationSettingsAndroid, iOS: initializationSettingsIOS);
+    await notifsPlugin.initialize(initializationSettings,
+        onSelectNotification: (String payload) async {
+          if (payload != null) {
+            print('notification payload: ' + payload);
+          }
+          selectNotificationSubject.add(payload);
+        });
+    print("Notifications initialised successfully");
+  }
+}
+
+Future<void> scheduleNotification(String title, String description,
+    notifs.FlutterLocalNotificationsPlugin notifsPlugin,
+    DateTime scheduledTime, {String id}) async {
+  if(scheduledTime.difference(DateTime.now()) < Duration.zero)
+    return;
+  if(id == null)
+    id = DateTime.now().toString();
+  var androidSpecifics = notifs.AndroidNotificationDetails(
+      "Vikunja",
+      "Due Date Reminder",
+      channelDescription: "description",
+      icon: 'vikunja_logo',
+      importance: notifs.Importance.high
+  );
+  var iOSSpecifics = notifs.IOSNotificationDetails();
+  var platformChannelSpecifics = notifs.NotificationDetails(
+      android: androidSpecifics, iOS: iOSSpecifics);
+  final String currentTimeZone = await FlutterNativeTimezone.getLocalTimezone();
+  tz.TZDateTime time = tz.TZDateTime.from(scheduledTime,tz.getLocation(currentTimeZone));
+  //time.add(Duration(hours: -2));
+  await notifsPlugin.zonedSchedule(Random().nextInt(100000000), title, description,
+      time, platformChannelSpecifics, androidAllowWhileIdle: true, uiLocalNotificationDateInterpretation: notifs.UILocalNotificationDateInterpretation.wallClockTime); // This literally schedules the notification
+}
+
+void requestIOSPermissions(
+    notifs.FlutterLocalNotificationsPlugin notifsPlugin) {
+  notifsPlugin.resolvePlatformSpecificImplementation<notifs.IOSFlutterLocalNotificationsPlugin>()
+      ?.requestPermissions(
+    alert: true,
+    badge: true,
+    sound: true,
+  );
+}

lib/pages/landing_page.dart

@@ -4,6 +4,8 @@ import 'package:vikunja_app/global.dart';
 import '../components/AddDialog.dart';
 import '../components/TaskTile.dart';
 import '../models/task.dart';
+import '../managers/notifications.dart';
+import '../main.dart';
 
 class LandingPage extends StatefulWidget {
   @override
@@ -25,6 +27,7 @@ class LandingPageState extends State<LandingPage> {
   Widget build(BuildContext context) {
     if(_list == null)
       _loadList(context);
+    VikunjaGlobal.of(context).scheduleDueNotifications();
     return new Scaffold(
         body: new Column(
           mainAxisAlignment: MainAxisAlignment.start,

lib/service/mocked_services.dart

@@ -178,6 +178,12 @@ class MockedTaskService implements TaskService {
     // TODO: implement getByOptions
     throw UnimplementedError();
   }
+
+  @override
+  Future<List<Task>> getAll() {
+    // TODO: implement getAll
+    throw UnimplementedError();
+  }
 }
 
 class MockedUserService implements UserService {

lib/service/services.dart

@@ -92,6 +92,7 @@ abstract class TaskService {
   Future<Task> update(Task task);
   Future delete(int taskId);
   Future<Task> add(int listId, Task task);
+  Future<List<Task>> getAll();
   Future<List<Task>> getByOptions(TaskServiceOptions options);
   }
 

lib/utils/misc.dart

@@ -3,9 +3,15 @@ String durationToHumanReadable(Duration dur) {
     return dur.inDays.toString() + " days";
   if(dur.inDays.abs() == 1)
     return dur.inDays.toString() + " day";
+
   if(dur.inHours.abs() > 1)
     return dur.inHours.toString() + " hours";
   if(dur.inHours.abs() == 1)
-    return dur.inHours.toString() + "1 hour";
-  return "under 1 hour";
+    return dur.inHours.toString() + " hour";
+
+  if(dur.inMinutes.abs() > 1)
+    return dur.inMinutes.toString() + " minutes";
+  if(dur.inMinutes.abs() == 1)
+    return dur.inMinutes.toString() + " minute";
+  return "under 1 minute";
 }