(bug) unable to update availability slot end time for training

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ## Next release
 
+- Fix a bug: unable to update availability slot end time for training
+
 ## v6.3.22 2024 Avril 29
 
 - Fix a security issue: updated rails to 7.0.8.1 to fix [CVE-2024-26143](https://github.com/rails/rails/security/advisories/GHSA-9822-6m93-xqf4)

app/frontend/src/javascript/controllers/admin/calendar.js

@@ -1009,18 +1009,6 @@ Application.Controllers.controller('CreateEventModalController', ['$scope', '$ui
         $scope.availability.start_at = $scope.start;
       });
 
-      // Maintain consistency between the end time and the date object in the availability object
-      $scope.$watch('end', function (newValue, oldValue, scope) {
-        if (newValue.valueOf() !== oldValue.valueOf()) {
-          // we prevent the admin from setting the end of the availability before its beginning
-          if (moment($scope.start).add($scope.availability.slot_duration, 'minutes').isAfter(newValue)) {
-            $scope.end = oldValue;
-          }
-          // update availability object
-          $scope.availability.end_at = $scope.end;
-        }
-      });
-
       $scope.$watch('startTime', function (newValue, oldValue, scope) {
         // adjust the start/endTime
         const start = moment($scope.start);
@@ -1031,6 +1019,15 @@ Application.Controllers.controller('CreateEventModalController', ['$scope', '$ui
         $scope.start = start.toDate();
         $scope.endTime = endTime.toDate();
       });
+
+      $scope.$watch('endTime', function (newValue, oldValue, scope) {
+        // adjust the start/endTime
+        const end = moment($scope.end);
+        const diff = moment.tz(newValue, moment.tz.guess()).diff(moment.tz(oldValue, moment.tz.guess()));
+        end.add(diff, 'milliseconds');
+        $scope.end = end.toDate();
+        $scope.availability.end_at = $scope.end;
+      });
     };
 
     /*