Auto dismiss replaceable notifications (#711)

lib/bindings/langs/swift/Sources/BreezSDKLiquid/TaskProtocol.swift

@@ -10,6 +10,28 @@ public protocol TaskProtocol : EventListener {
 }
 
 extension TaskProtocol {
+    func removePushNotifications(threadIdentifier: String, logger: ServiceLogger) {
+        let semaphore = DispatchSemaphore(value: 0)
+        let notificationCenter = UNUserNotificationCenter.current()
+
+        notificationCenter.getDeliveredNotifications(completionHandler: { notifications in
+            defer {
+                semaphore.signal()
+            }
+
+            let removableNotifications = notifications.filter({ $0.request.content.threadIdentifier == threadIdentifier })
+            guard !removableNotifications.isEmpty else {
+                return
+            }
+            // The call to removeDeliveredNotifications() is async in a background thread and
+            // needs to be complete before calling contentHandler()
+            notificationCenter.removeDeliveredNotifications(withIdentifiers: removableNotifications.map({ $0.request.identifier }))
+            logger.log(tag: "TaskProtocol", line:"removePushNotifications: \(removableNotifications.count)", level: "INFO")
+        })
+
+        semaphore.wait()
+    }
+
     func displayPushNotification(title: String, body: String? = nil, logger: ServiceLogger, threadIdentifier: String? = nil) {
         logger.log(tag: "TaskProtocol", line:"displayPushNotification \(title)", level: "INFO")
         guard
@@ -18,6 +40,8 @@ extension TaskProtocol {
         else {
             return
         }
+
+        removePushNotifications(threadIdentifier: Constants.NOTIFICATION_THREAD_REPLACEABLE, logger: logger)
         
         if let body = body {
             bestAttemptContent.body = body
@@ -28,6 +52,10 @@ extension TaskProtocol {
         }
         
         bestAttemptContent.title = title
-        contentHandler(bestAttemptContent)
+        // The call to contentHandler() needs to be done with a slight delay otherwise
+        // it will be killed before its finished removing the notifications
+        DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
+            contentHandler(bestAttemptContent)
+        }
     }
 }