Refactor Bolus recommendation code

Loop/Managers/LoopDataManager.swift

@@ -299,7 +299,7 @@ final class LoopDataManager {
                     do {
                         try self.update()
 
-                        completion(.success(try self.recommendBolus()))
+                        completion(.success(self.recommendedBolus?.recommendation))
                     } catch let error {
                         completion(.failure(error))
                     }
@@ -586,7 +586,7 @@ final class LoopDataManager {
 
         if predictedGlucose == nil {
             do {
-                try updatePredictedGlucoseAndRecommendedBasal()
+                try updatePredictedGlucoseAndRecommendedBasalAndBolus()
             } catch let error {
                 logger.error(error)
 
@@ -717,6 +717,7 @@ final class LoopDataManager {
     fileprivate var predictedGlucose: [GlucoseValue]? {
         didSet {
             recommendedTempBasal = nil
+            recommendedBolus = nil
         }
     }
     fileprivate var retrospectivePredictedGlucose: [GlucoseValue]? {
@@ -726,6 +727,8 @@ final class LoopDataManager {
     }
     fileprivate var recommendedTempBasal: (recommendation: TempBasalRecommendation, date: Date)?
 
+    fileprivate var recommendedBolus: (recommendation: BolusRecommendation, date: Date)?
+
     fileprivate var carbsOnBoard: CarbValue?
 
     fileprivate var lastTempBasal: DoseEntry?
@@ -841,7 +844,7 @@ final class LoopDataManager {
     ///     - LoopError.glucoseTooOld
     ///     - LoopError.missingDataError
     ///     - LoopError.pumpDataTooOld
-    private func updatePredictedGlucoseAndRecommendedBasal() throws {
+    private func updatePredictedGlucoseAndRecommendedBasalAndBolus() throws {
         dispatchPrecondition(condition: .onQueue(dataAccessQueue))
 
         guard let glucose = glucoseStore.latestGlucose else {
@@ -879,14 +882,25 @@ final class LoopDataManager {
             let glucoseTargetRange = settings.glucoseTargetRangeSchedule,
             let insulinSensitivity = insulinSensitivitySchedule,
             let basalRates = basalRateSchedule,
+            let maxBolus = settings.maximumBolus,
             let model = insulinModelSettings?.model
         else {
             throw LoopError.configurationError("Check settings")
         }
+
+        let pendingInsulin = try self.getPendingInsulin()
 
-        guard
-            lastRequestedBolus == nil,  // Don't recommend changes if a bolus was just set
-            let tempBasal = predictedGlucose.recommendedTempBasal(
+        guard lastRequestedBolus == nil
+        else {
+            // Don't recommend changes if a bolus was just requested.
+            // Sending additional pump commands is not going to be
+            // successful in any case.
+            recommendedBolus = nil
+            recommendedTempBasal = nil
+            return
+        }
+
+        let tempBasal = predictedGlucose.recommendedTempBasal(
                 to: glucoseTargetRange,
                 suspendThreshold: settings.suspendThreshold?.quantity,
                 sensitivity: insulinSensitivity,
@@ -895,42 +909,13 @@ final class LoopDataManager {
                 maxBasalRate: maxBasal,
                 lastTempBasal: lastTempBasal
             )
-        else {
+
+        if let temp = tempBasal {
+            recommendedTempBasal = (recommendation: temp, date: startDate)
+        } else {
             recommendedTempBasal = nil
-            return
-        }
-
-        recommendedTempBasal = (recommendation: tempBasal, date: Date())
-    }
-
-    /// - Returns: A bolus recommendation from the current data
-    /// - Throws: 
-    ///     - LoopError.configurationError
-    ///     - LoopError.glucoseTooOld
-    ///     - LoopError.missingDataError
-    fileprivate func recommendBolus() throws -> BolusRecommendation {
-        dispatchPrecondition(condition: .onQueue(dataAccessQueue))
-
-        guard
-            let predictedGlucose = predictedGlucose,
-            let maxBolus = settings.maximumBolus,
-            let glucoseTargetRange = settings.glucoseTargetRangeSchedule,
-            let insulinSensitivity = insulinSensitivitySchedule,
-            let model = insulinModelSettings?.model
-        else {
-            throw LoopError.configurationError("Check Settings")
-        }
-
-        guard let glucoseDate = predictedGlucose.first?.startDate else {
-            throw LoopError.missingDataError(details: "No glucose data found", recovery: "Check your CGM source")
         }
-
-        guard abs(glucoseDate.timeIntervalSinceNow) <= recencyInterval else {
-            throw LoopError.glucoseTooOld(date: glucoseDate)
-        }
-
-        let pendingInsulin = try self.getPendingInsulin()
-
+
         let recommendation = predictedGlucose.recommendedBolus(
             to: glucoseTargetRange,
             suspendThreshold: settings.suspendThreshold?.quantity,
@@ -939,8 +924,7 @@ final class LoopDataManager {
             pendingInsulin: pendingInsulin,
             maxBolus: maxBolus
         )
-
-        return recommendation
+        recommendedBolus = (recommendation: recommendation, date: startDate)
     }
 
     /// *This method should only be called from the `dataAccessQueue`*
@@ -997,6 +981,8 @@ protocol LoopState {
     /// The recommended temp basal based on predicted glucose
     var recommendedTempBasal: (recommendation: TempBasalRecommendation, date: Date)? { get }
 
+    var recommendedBolus: (recommendation: BolusRecommendation, date: Date)? { get }
+
     /// The retrospective prediction over a recent period of glucose samples
     var retrospectivePredictedGlucose: [GlucoseValue]? { get }
 
@@ -1008,15 +994,6 @@ protocol LoopState {
     /// - Returns: An timeline of predicted glucose values
     /// - Throws: LoopError.missingDataError if prediction cannot be computed
     func predictGlucose(using inputs: PredictionInputEffect) throws -> [GlucoseValue]
-
-    /// Calculates a recommended bolus based on predicted glucose
-    ///
-    /// - Returns: A bolus recommendation
-    /// - Throws: An error describing why a bolus couldnʼt be computed
-    ///     - LoopError.configurationError
-    ///     - LoopError.glucoseTooOld
-    ///     - LoopError.missingDataError
-    func recommendBolus() throws -> BolusRecommendation
 }
 
 
@@ -1064,6 +1041,11 @@ extension LoopDataManager {
             dispatchPrecondition(condition: .onQueue(loopDataManager.dataAccessQueue))
             return loopDataManager.recommendedTempBasal
         }
+
+        var recommendedBolus: (recommendation: BolusRecommendation, date: Date)? {
+            dispatchPrecondition(condition: .onQueue(loopDataManager.dataAccessQueue))
+            return loopDataManager.recommendedBolus
+        }
 
         var retrospectivePredictedGlucose: [GlucoseValue]? {
             dispatchPrecondition(condition: .onQueue(loopDataManager.dataAccessQueue))
@@ -1073,10 +1055,6 @@ extension LoopDataManager {
         func predictGlucose(using inputs: PredictionInputEffect) throws -> [GlucoseValue] {
             return try loopDataManager.predictGlucose(using: inputs)
         }
-
-        func recommendBolus() throws -> BolusRecommendation {
-            return try loopDataManager.recommendBolus()
-        }
     }
 
     /// Executes a closure with access to the current state of the loop.
@@ -1118,6 +1096,7 @@ extension LoopDataManager {
                 "predictedGlucose: \(state.predictedGlucose ?? [])",
                 "retrospectivePredictedGlucose: \(state.retrospectivePredictedGlucose ?? [])",
                 "recommendedTempBasal: \(String(describing: state.recommendedTempBasal))",
+                "recommendedBolus: \(String(describing: state.recommendedBolus))",
                 "lastBolus: \(String(describing: manager.lastRequestedBolus))",
                 "lastGlucoseChange: \(String(describing: manager.lastGlucoseChange))",
                 "retrospectiveGlucoseChange: \(String(describing: manager.retrospectiveGlucoseChange))",

Loop/Managers/NightscoutDataManager.swift

@@ -43,15 +43,7 @@ final class NightscoutDataManager {
             var loopError = state.error
             let recommendedBolus: Double?
 
-            do {
-                recommendedBolus = try state.recommendBolus().amount
-            } catch let error {
-                recommendedBolus = nil
-
-                if loopError == nil {
-                    loopError = error
-                }
-            }
+            recommendedBolus = state.recommendedBolus?.recommendation.amount
 
             let carbsOnBoard = state.carbsOnBoard
             let predictedGlucose = state.predictedGlucose

Loop/Managers/WatchDataManager.swift

@@ -125,7 +125,7 @@ final class WatchDataManager: NSObject, WCSessionDelegate {
                 context.reservoir = reservoir?.unitVolume
 
                 context.loopLastRunDate = state.lastLoopCompleted
-                context.recommendedBolusDose = try? state.recommendBolus().amount
+                context.recommendedBolusDose = state.recommendedBolus?.recommendation.amount
                 context.maxBolus = manager.settings.maximumBolus
 
                 if let glucoseTargetRangeSchedule = manager.settings.glucoseTargetRangeSchedule {

Loop/View Controllers/BolusViewController+LoopDataManager.swift

@@ -20,7 +20,7 @@ extension BolusViewController {
             if let recommendation = recommendation {
                 bolusRecommendation = recommendation
             } else {
-                bolusRecommendation = try? state.recommendBolus()
+                bolusRecommendation = state.recommendedBolus?.recommendation
             }
 
             manager.doseStore.insulinOnBoard(at: Date()) { (result) in