Merge pull request #424 from loopandlearn/not-looping-last-checked

Prevent stale "Not Looping" alarms

Author: bjorkert

LoopFollow/Alarm/AlarmCondition/NotLoopingCondition.swift

@@ -8,7 +8,7 @@ struct NotLoopingCondition: AlarmCondition {
     static let type: AlarmType = .notLooping
     init() {}
 
-    func evaluate(alarm: Alarm, data: AlarmData, now _: Date) -> Bool {
+    func evaluate(alarm: Alarm, data: AlarmData, now: Date) -> Bool {
         // ────────────────────────────────
         // 0. sanity checks
         // ────────────────────────────────
@@ -19,6 +19,17 @@ struct NotLoopingCondition: AlarmCondition {
         guard let lastLoopTime = data.lastLoopTime,
               lastLoopTime > 0 else { return false }
 
+        guard let lastChecked = Storage.shared.lastLoopingChecked.value else {
+            // Never checked, so don't alarm.
+            return false
+        }
+
+        let checkedAgeSeconds = now.timeIntervalSince(lastChecked)
+        if checkedAgeSeconds > 360 { // 6 minutes
+            // The check itself is stale, so the data is unreliable. Don't alarm.
+            return false
+        }
+
         // ────────────────────────────────
         // 1. elapsed-time test
         // ────────────────────────────────

LoopFollow/Controllers/Nightscout/DeviceStatus.swift

@@ -8,6 +8,8 @@ import UIKit
 
 extension MainViewController {
     func webLoadNSDeviceStatus() {
+        Storage.shared.lastLoopingChecked.value = Date()
+
         let parameters = ["count": "1"]
         NightscoutUtils.executeDynamicRequest(eventType: .deviceStatus, parameters: parameters) { result in
             switch result {

LoopFollow/Storage/Storage.swift

@@ -160,6 +160,8 @@ class Storage {
     var persistentNotification = StorageValue<Bool>(key: "persistentNotification", defaultValue: false)
     var persistentNotificationLastBGTime = StorageValue<Date>(key: "persistentNotificationLastBGTime", defaultValue: .distantPast)
 
+    var lastLoopingChecked = StorageValue<Date?>(key: "lastLoopingChecked", defaultValue: nil)
+
     static let shared = Storage()
     private init() {}
 }