Attempt to refresh live activity with background refreshes

LeCountdown/Conductor.swift

@@ -7,6 +7,7 @@
 
 import Foundation
 import ActivityKit
+import BackgroundTasks
 
 class Conductor : ObservableObject {
     
@@ -49,10 +50,10 @@ class Conductor : ObservableObject {
             if !cancel {
                 self._recordActivity(countdownId: countdownId)
             }
-            self.notificationDates.removeValue(forKey: countdownId)
             
-//            self._updateLiveActivity(countdownId: countdownId, endDate: <#T##Date#>)
-            self._endLiveActivity(countdownId: countdownId)
+            if self.notificationDates.removeValue(forKey: countdownId) != nil {
+                self._endLiveActivity(countdownId: countdownId)
+            }
         }
     }
     
@@ -114,11 +115,25 @@ class Conductor : ObservableObject {
 
             do {
                 let liveActivity = try ActivityKit.Activity.request(attributes: attributes, content: activityContent)
-                print("Requested a countdown Live Activity \(String(describing: liveActivity.id)).")
+                print("Requested a Countdown Live Activity: \(String(describing: liveActivity.id)).")
             } catch (let error) {
                 print("Error requesting countdown Live Activity \(error.localizedDescription).")
             }
 
+            self._scheduleAppRefresh(countdown: countdown)
+            
+        }
+    }
+    
+    fileprivate func _scheduleAppRefresh(countdown: Countdown) {
+        let request = BGAppRefreshTaskRequest(identifier: BGTaskIdentifier.refresh.rawValue)
+        request.earliestBeginDate = Date(timeIntervalSinceNow: countdown.duration)
+        
+        do {
+            try BGTaskScheduler.shared.submit(request)
+            print("request submitted with date: \(String(describing: request.earliestBeginDate))")
+        } catch {
+            print("Could not schedule app refresh: \(error)")
         }
     }
     
@@ -127,25 +142,36 @@ class Conductor : ObservableObject {
     }
     
     func updateLiveActivities() {
+        print("update live activity...")
         
         for (countdownId, interval) in self.notificationDates {
-            if let activity = self._liveActivity(countdownId: countdownId) {
-                
-                Task {
-                    let ended = interval.end < Date()
-                    let state = LaunchWidgetAttributes.ContentState(ended: ended)
-                    let content = ActivityContent(state: state, staleDate: interval.end)
-                    await activity.update(content)
-                    print("Ending the Live Activity: \(activity.id)")
-                }
+            
+            if interval.end < Date() {
+                self._endLiveActivity(countdownId: countdownId)
             }
+
+            
+//            if let activity = self._liveActivity(countdownId: countdownId) {
+//
+//                Task {
+//
+//                    if ended {
+//                        self._endLiveActivity(countdownId: countdownId)
+//                    }
+//
+////                    let state = LaunchWidgetAttributes.ContentState(ended: ended)
+////                    let content = ActivityContent(state: state, staleDate: interval.end)
+////                    await activity.update(content)
+////                    print("Ending the Live Activity: \(activity.id)")
+//                }
+//            }
         }
         
     }
     
     fileprivate func _endLiveActivity(countdownId: String) {
         
-        print("Trt to end the Live Activity: \(countdownId)")
+        print("Try to end the Live Activity: \(countdownId)")
 
         if let activity = self._liveActivity(countdownId: countdownId) {
             Task {

LeCountdown/CountdownScheduler.swift

@@ -53,7 +53,7 @@ class CountdownScheduler {
         
         let duration = countdown.duration
         let trigger = UNTimeIntervalNotificationTrigger(timeInterval: duration + offset, repeats: false)
-        let request = UNNotificationRequest(identifier: countdown.objectID.uriRepresentation().absoluteString + "/\(offset)",
+        let request = UNNotificationRequest(identifier: countdown.objectID.uriRepresentation().absoluteString,
                                             content: content,
                                             trigger: trigger)
         UNUserNotificationCenter.current().add(request) { error in

LeCountdown/Info.plist

@@ -2,6 +2,10 @@
 <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 <plist version="1.0">
 <dict>
+	<key>BGTaskSchedulerPermittedIdentifiers</key>
+	<array>
+		<string>com.staxriver.lecountdown.refresh</string>
+	</array>
 	<key>NSUserActivityTypes</key>
 	<array>
 		<string>SelectCountdownIntent</string>
@@ -16,6 +20,7 @@
 	<key>UIBackgroundModes</key>
 	<array>
 		<string>audio</string>
+		<string>fetch</string>
 	</array>
 </dict>
 </plist>

LeCountdown/LeCountdownApp.swift

@@ -6,6 +6,11 @@
 //
 
 import SwiftUI
+import BackgroundTasks
+
+enum BGTaskIdentifier : String {
+    case refresh = "com.staxriver.lecountdown.refresh"
+}
 
 @main
 struct LeCountdownApp: App {
@@ -32,6 +37,8 @@ struct LeCountdownApp: App {
     }
     
     fileprivate func _onAppear() {
+        self._registerBackgroundRefreshes()
+        
 //        Task {
 //            for s in Sound.allCases {
 //                do {
@@ -43,5 +50,26 @@ struct LeCountdownApp: App {
 //            }
 //        }
     }
+ 
+    fileprivate func _registerBackgroundRefreshes() {
+        BGTaskScheduler.shared.register(forTaskWithIdentifier: BGTaskIdentifier.refresh.rawValue, using: nil) { task in
+             self._handleAppRefresh(task: task as! BGAppRefreshTask)
+        }
+    }
+    
+    fileprivate func _handleAppRefresh(task: BGAppRefreshTask) {
+        
+        print("_handleAppRefresh = \(task.description)")
+        
+        task.expirationHandler = {
+            print("expired")
+        }
+        
+        DispatchQueue.main.async {
+            Conductor.maestro.updateLiveActivities()
+            task.setTaskCompleted(success: true)
+        }
+        
+    }
     
 }