Expired beacons fix. (#33)

* Expired Duration Fix: Part 1.
Show expired beacons at the very last in your beacons section + No streams should be running (including the one that tracks location)
Tried to implement this.
* Cancelling StreamSubs if beacon expires when subs are active.
* minor miss: setting isBeaconExpired to true.
* Upd: Showing snackBar if user tries to join an expired beacon.
* fix: Updated setting up subscriptions logic.
* fix: setting state so that UI updates if beacon expires.
* FIX: Close the circular loading spinner if there was some error in joining any beacon.
* Update lib/views/hike_screen.dart
* fix: Change the msg to terminate hike if beacon has expired.

Co-authored-by: Nishtha Bodani <nbodani8@gmail.com>

lib/components/beacon_card.dart

@@ -31,9 +31,8 @@ class BeaconCustomWidgets {
           if (_beacon != null) {
             navigationService.pushScreen('/hikeScreen',
                 arguments: HikeScreen(beacon, isLeader: false));
-          } else {
-            navigationService.showSnackBar('Something went wrong');
           }
+          //Snackbar is displayed by joinBeacon itself on any error or trying to join expired beacon.
         }
       },
       child: Container(

lib/components/dialog_boxes.dart

@@ -6,16 +6,18 @@ import 'package:sizer/sizer.dart';
 
 class DialogBoxes {
   static AlertDialog showExitDialog(
-      BuildContext context, bool isLeader, int X) {
+      BuildContext context, bool isLeader, int X, bool isBeaconExpired) {
     return AlertDialog(
       title: Text(
         'This will terminate the hike, Confirm?',
         style: TextStyle(fontSize: 25, color: kYellow),
       ),
       content: Text(
-        isLeader && (X - 1 > 0)
-            ? 'There are ${X - 1} followers and you are carrying the beacon. Do you want to terminate the hike?'
-            : 'Are you sure you want to terminate the hike?',
+        isBeaconExpired
+            ? 'Are you sure you want to exit?'
+            : isLeader && (X - 1 > 0)
+                ? 'There are ${X - 1} followers and you are carrying the beacon. Do you want to terminate the hike?'
+                : 'Are you sure you want to terminate the hike?',
         style: TextStyle(fontSize: 16, color: kBlack),
       ),
       actionsAlignment: MainAxisAlignment.spaceEvenly,

lib/services/database_mutation_functions.dart

@@ -184,6 +184,7 @@ class DataBaseMutationFunctions {
   Future<List<Beacon>> fetchUserBeacons() async {
     List<Beacon> beacons = [];
     Set<String> beaconIds = {};
+    List<Beacon> expiredBeacons = [];
     final QueryResult result = await clientAuth
         .query(QueryOptions(document: gql(_authQuery.fetchUserInfo())));
     if (result.hasException) {
@@ -199,10 +200,15 @@ class DataBaseMutationFunctions {
       for (var i in userInfo.beacon) {
         if (!beaconIds.contains(i.id)) {
           beaconIds.add(i.id);
-          beacons.add(i);
+          if (DateTime.fromMillisecondsSinceEpoch(i.expiresAt)
+              .isBefore(DateTime.now()))
+            expiredBeacons.add(i);
+          else
+            beacons.add(i);
         }
       }
     }
+    beacons.addAll(expiredBeacons);
     return beacons;
   }
 
@@ -261,8 +267,17 @@ class DataBaseMutationFunctions {
       final Beacon beacon = Beacon.fromJson(
         result.data['joinBeacon'] as Map<String, dynamic>,
       );
+      if (DateTime.fromMillisecondsSinceEpoch(beacon.expiresAt)
+          .isBefore(DateTime.now())) {
+        navigationService.showSnackBar(
+            "Looks like the beacon you are trying join has expired");
+        return null;
+      }
       beacon.route.add(beacon.leader.location);
       return beacon;
+    } else {
+      navigationService
+          .showSnackBar("Something went wrong while trying to join Beacon");
     }
     return null;
   }

lib/view_model/home_view_model.dart

@@ -54,8 +54,10 @@ class HomeViewModel extends BaseModel {
         navigationService.pushScreen('/hikeScreen',
             arguments: HikeScreen(beacon, isLeader: false));
       } else {
-        navigationService.showSnackBar('SomeThing went wrong');
+        //there was some error, go back to homescreen.
+        setState(ViewState.idle);
       }
+      //Snackbar is displayed by joinBeacon itself on any error or trying to join expired beacon.
     } else {
       navigationService.showSnackBar('Enter valid passkey');
     }

lib/views/hike_screen.dart

@@ -77,12 +77,15 @@ class _HikeScreenState extends State<HikeScreen> {
     });
   }
 
-  Future<void> setupSubscriptions() async {
+  Future<void> setupSubscriptions(bool isExpired) async {
+    if (isBeaconExpired || isExpired) return;
     if (widget.isLeader) {
       // distanceFilter (in m) can be changed to reduce the backend calls
       await loc.changeSettings(interval: 3000, distanceFilter: 0.0);
       _leaderLocation =
           loc.onLocationChanged.listen((LocationData currentLocation) async {
+        if (DateTime.fromMillisecondsSinceEpoch(beacon.expiresAt)
+            .isBefore(DateTime.now())) _leaderLocation.cancel();
         Coordinates coordinates =
             Coordinates(currentLocation.latitude, currentLocation.longitude);
         var addresses =
@@ -125,7 +128,15 @@ class _HikeScreenState extends State<HikeScreen> {
     } else {
       mergedStream = beaconJoinedStream;
     }
-    final mergeStreamSubscription = mergedStream.listen((event) async {
+    StreamSubscription<dynamic> mergeStreamSubscription;
+    mergeStreamSubscription = mergedStream.listen((event) async {
+      if (DateTime.fromMillisecondsSinceEpoch(beacon.expiresAt)
+          .isBefore(DateTime.now())) {
+        mergeStreamSubscription.cancel();
+        setState(() {
+          isBeaconExpired = true;
+        });
+      }
       if (event.data != null) {
         print('${event.data}');
         if (event.data.containsKey('beaconJoined')) {
@@ -194,12 +205,13 @@ class _HikeScreenState extends State<HikeScreen> {
 
   @override
   void dispose() {
-    if (widget.isLeader) {
+    if (widget.isLeader && !isBeaconExpired) {
       _leaderLocation.cancel();
     }
-    for (var streamSub in mergedStreamSubscriptions) {
-      streamSub.cancel();
-    }
+    if (!isBeaconExpired)
+      for (var streamSub in mergedStreamSubscriptions) {
+        streamSub.cancel();
+      }
     super.dispose();
   }
 
@@ -234,6 +246,8 @@ class _HikeScreenState extends State<HikeScreen> {
     await databaseFunctions.fetchBeaconInfo(widget.beacon.id).then((value) {
       beacon = value;
       setState(() {
+        isBeaconExpired = DateTime.fromMillisecondsSinceEpoch(beacon.expiresAt)
+            .isBefore(DateTime.now());
         hikers.add(value.leader);
         for (var i in value.followers) {
           if (!followerId.contains(i.id)) {
@@ -294,7 +308,8 @@ class _HikeScreenState extends State<HikeScreen> {
     beacon = widget.beacon;
     fetchData();
     graphQlClient = GraphQLConfig().graphQlClient();
-    setupSubscriptions();
+    setupSubscriptions(DateTime.fromMillisecondsSinceEpoch(beacon.expiresAt)
+        .isBefore(DateTime.now()));
     isBusy = false;
   }
 
@@ -365,8 +380,9 @@ class _HikeScreenState extends State<HikeScreen> {
                                                 'Total Followers: ${hikers.length - 1} (Swipe up to view the list of followers)\n',
                                             style: TextStyle(fontSize: 12)),
                                         TextSpan(
-                                            text:
-                                                'Share this passkey to add user: ${widget.beacon.shortcode}\n',
+                                            text: isBeaconExpired
+                                                ? ''
+                                                : 'Share this passkey to add user: ${widget.beacon.shortcode}\n',
                                             style: TextStyle(fontSize: 12)),
                                       ]),
                                 ),
@@ -502,8 +518,10 @@ class _HikeScreenState extends State<HikeScreen> {
                           ),
                           Align(
                               alignment: Alignment(0.87, -0.85),
-                              child: HikeScreenWidget.shareButton(
-                                  context, widget.beacon.shortcode)),
+                              child: isBeaconExpired
+                                  ? Container()
+                                  : HikeScreenWidget.shareButton(
+                                      context, widget.beacon.shortcode)),
                           Align(
                             alignment: Alignment(-0.8, -0.9),
                             child: GestureDetector(
@@ -642,7 +660,7 @@ class _HikeScreenState extends State<HikeScreen> {
     return (await showDialog(
           context: context,
           builder: (context) => DialogBoxes.showExitDialog(
-              context, widget.isLeader, hikers.length),
+              context, widget.isLeader, hikers.length, isBeaconExpired),
         )) ??
         false;
   }