fixing the crash on repeating timer

Author: RiishavRG

Sources/ClickstreamLib/NetworkManager/Infrastructure/Utilities/DispatchSourceTimer+RepeatingTimer.swift

@@ -13,8 +13,14 @@ import Foundation
 /// crashes that occur from calling resume multiple times on a timer that is
 /// already resumed (noted by https://github.com/SiftScience/sift-ios/issues/52)
 class RepeatingTimer {
+
+    static let shared = RepeatingTimer()
+    
+    var timeInterval: TimeInterval = 0
+    
+    private var suspensionCount = 0
 
-    let timeInterval: TimeInterval
+    private init() { }
 
     init(timeInterval: TimeInterval) {
         self.timeInterval = timeInterval
@@ -41,33 +47,45 @@ class RepeatingTimer {
     deinit {
         timer.setEventHandler {}
         timer.cancel()
-        if !Clickstream.timerCrashFixFlag {
-            /*
-             If the timer is suspended, calling cancel without resuming
-             triggers a crash. This is documented here https://forums.developer.apple.com/thread/15902
-             */
-            resume()
-        }
+        /*
+         If the timer is suspended, calling cancel without resuming
+         triggers a crash. This is documented here https://forums.developer.apple.com/thread/15902
+         */
+        resume()
         eventHandler = nil
     }
 
     func resume() {
         if state.value == .resumed {
             return
         }
+        suspensionCount -= 1
         state.mutate { state in
             state = .resumed
         }
-        timer.resume()
+        if Clickstream.timerCrashFixFlag {
+            if suspensionCount > 0 {
+                self.timer.resume()
+            }
+        } else {
+            timer.resume()
+        }
     }
 
     func suspend() {
         if state.value == .suspended {
             return
         }
+        suspensionCount += 1
         state.mutate { state in
             state = .suspended
         }
-        timer.suspend()
+        if Clickstream.timerCrashFixFlag {
+            if suspensionCount > 0 {
+                timer.suspend()
+            }
+        } else {
+            timer.suspend()
+        }
     }
 }

Sources/ClickstreamLib/NetworkManager/Infrastructure/Utilities/KeepAliveService.swift

@@ -89,15 +89,28 @@ final class DefaultKeepAliveServiceWithSafeTimer: KeepAliveService {
 
     @discardableResult
     private func makeTimer() -> RepeatingTimer? {
-        let timerDuration = duration*reachability.connectionRetryCoefficient
-        timer = RepeatingTimer(timeInterval: timerDuration)
-        timer?.eventHandler = { [weak self] in
-            guard let checkedSelf = self else { return }
-            checkedSelf.performQueue.async {
-                checkedSelf.subscriber?()
+        if Clickstream.timerCrashFixFlag {
+            let timerDuration = duration*reachability.connectionRetryCoefficient
+            RepeatingTimer.shared.timeInterval = timerDuration
+            self.timer = RepeatingTimer.shared
+            timer?.eventHandler = { [weak self] in
+                guard let checkedSelf = self else { return }
+                checkedSelf.performQueue.async {
+                    checkedSelf.subscriber?()
+                }
+            }
+            return timer
+        } else {
+            let timerDuration = duration*reachability.connectionRetryCoefficient
+            self.timer = RepeatingTimer(timeInterval: timerDuration)
+            timer?.eventHandler = { [weak self] in
+                guard let checkedSelf = self else { return }
+                checkedSelf.performQueue.async {
+                    checkedSelf.subscriber?()
+                }
             }
+            return timer
         }
-        return timer
     }
 
     func stop() {