Glucose Based Partial Application Factor

Common/FeatureFlags.swift

@@ -39,6 +39,7 @@ struct FeatureFlagConfiguration: Decodable {
     let adultChildInsulinModelSelectionEnabled: Bool
     let profileExpirationSettingsViewEnabled: Bool
     let missedMealNotifications: Bool
+    let allowAlgorithmExperiments: Bool
 
 
     fileprivate init() {
@@ -229,6 +230,11 @@ struct FeatureFlagConfiguration: Decodable {
         self.missedMealNotifications = true
         #endif
 
+        #if ALLOW_ALGORITHM_EXPERIMENTS
+        self.allowAlgorithmExperiments = true
+        #else
+        self.allowAlgorithmExperiments = false
+        #endif
     }
 }
 
@@ -263,7 +269,8 @@ extension FeatureFlagConfiguration : CustomDebugStringConvertible {
             "* dynamicCarbAbsorptionEnabled: \(dynamicCarbAbsorptionEnabled)",
             "* adultChildInsulinModelSelectionEnabled: \(adultChildInsulinModelSelectionEnabled)",
             "* profileExpirationSettingsViewEnabled: \(profileExpirationSettingsViewEnabled)",
-            "* missedMealNotifications: \(missedMealNotifications)"
+            "* missedMealNotifications: \(missedMealNotifications)",
+            "* allowAlgorithmExperiments: \(allowAlgorithmExperiments)"
         ].joined(separator: "\n")
     }
 }

Loop.xcodeproj/project.pbxproj

@@ -518,6 +518,11 @@
 		C1FB428D21791D2500FAB378 /* PumpManager.swift in Sources */ = {isa = PBXBuildFile; fileRef = 43C3B6F620BBCAA30026CAFA /* PumpManager.swift */; };
 		C1FB428F217921D600FAB378 /* PumpManagerUI.swift in Sources */ = {isa = PBXBuildFile; fileRef = C1FB428E217921D600FAB378 /* PumpManagerUI.swift */; };
 		C1FB4290217922A100FAB378 /* PumpManagerUI.swift in Sources */ = {isa = PBXBuildFile; fileRef = C1FB428E217921D600FAB378 /* PumpManagerUI.swift */; };
+		DDC389F62A2B61750066E2E8 /* ApplicationFactorStrategy.swift in Sources */ = {isa = PBXBuildFile; fileRef = DDC389F52A2B61750066E2E8 /* ApplicationFactorStrategy.swift */; };
+		DDC389F82A2B620B0066E2E8 /* GlucoseBasedApplicationFactorStrategy.swift in Sources */ = {isa = PBXBuildFile; fileRef = DDC389F72A2B620B0066E2E8 /* GlucoseBasedApplicationFactorStrategy.swift */; };
+		DDC389FA2A2B62470066E2E8 /* ConstantApplicationFactorStrategy.swift in Sources */ = {isa = PBXBuildFile; fileRef = DDC389F92A2B62470066E2E8 /* ConstantApplicationFactorStrategy.swift */; };
+		DDC389FC2A2BC6670066E2E8 /* SettingsView+algorithmExperimentsSection.swift in Sources */ = {isa = PBXBuildFile; fileRef = DDC389FB2A2BC6670066E2E8 /* SettingsView+algorithmExperimentsSection.swift */; };
+		DDC389FE2A2C4C830066E2E8 /* GlucoseBasedApplicationFactorSelectionView.swift in Sources */ = {isa = PBXBuildFile; fileRef = DDC389FD2A2C4C830066E2E8 /* GlucoseBasedApplicationFactorSelectionView.swift */; };
 		E90909D124E34AC500F963D2 /* high_and_rising_with_cob_momentum_effect.json in Resources */ = {isa = PBXBuildFile; fileRef = E90909CC24E34AC500F963D2 /* high_and_rising_with_cob_momentum_effect.json */; };
 		E90909D224E34AC500F963D2 /* high_and_rising_with_cob_insulin_effect.json in Resources */ = {isa = PBXBuildFile; fileRef = E90909CD24E34AC500F963D2 /* high_and_rising_with_cob_insulin_effect.json */; };
 		E90909D324E34AC500F963D2 /* high_and_rising_with_cob_predicted_glucose.json in Resources */ = {isa = PBXBuildFile; fileRef = E90909CE24E34AC500F963D2 /* high_and_rising_with_cob_predicted_glucose.json */; };
@@ -1687,6 +1692,11 @@
 		C1FF3D4B29C786A900BDC1EC /* he */ = {isa = PBXFileReference; lastKnownFileType = text.plist.strings; name = he; path = he.lproj/Localizable.strings; sourceTree = "<group>"; };
 		C1FF3D4C29C786A900BDC1EC /* he */ = {isa = PBXFileReference; lastKnownFileType = text.plist.strings; name = he; path = he.lproj/Localizable.strings; sourceTree = "<group>"; };
 		C1FF3D4D29C786A900BDC1EC /* he */ = {isa = PBXFileReference; lastKnownFileType = text.plist.strings; name = he; path = he.lproj/InfoPlist.strings; sourceTree = "<group>"; };
+		DDC389F52A2B61750066E2E8 /* ApplicationFactorStrategy.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ApplicationFactorStrategy.swift; sourceTree = "<group>"; };
+		DDC389F72A2B620B0066E2E8 /* GlucoseBasedApplicationFactorStrategy.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = GlucoseBasedApplicationFactorStrategy.swift; sourceTree = "<group>"; };
+		DDC389F92A2B62470066E2E8 /* ConstantApplicationFactorStrategy.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ConstantApplicationFactorStrategy.swift; sourceTree = "<group>"; };
+		DDC389FB2A2BC6670066E2E8 /* SettingsView+algorithmExperimentsSection.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "SettingsView+algorithmExperimentsSection.swift"; sourceTree = "<group>"; };
+		DDC389FD2A2C4C830066E2E8 /* GlucoseBasedApplicationFactorSelectionView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = GlucoseBasedApplicationFactorSelectionView.swift; sourceTree = "<group>"; };
 		E90909CC24E34AC500F963D2 /* high_and_rising_with_cob_momentum_effect.json */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.json; path = high_and_rising_with_cob_momentum_effect.json; sourceTree = "<group>"; };
 		E90909CD24E34AC500F963D2 /* high_and_rising_with_cob_insulin_effect.json */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.json; path = high_and_rising_with_cob_insulin_effect.json; sourceTree = "<group>"; };
 		E90909CE24E34AC500F963D2 /* high_and_rising_with_cob_predicted_glucose.json */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.json; path = high_and_rising_with_cob_predicted_glucose.json; sourceTree = "<group>"; };
@@ -2314,6 +2324,7 @@
 			isa = PBXGroup;
 			children = (
 				A98556842493F901000FD662 /* AlertStore+SimulatedCoreData.swift */,
+				DDC389FB2A2BC6670066E2E8 /* SettingsView+algorithmExperimentsSection.swift */,
 				C1D289B422F90A52003FFBD9 /* BasalDeliveryState.swift */,
 				A9F703722489BC8500C98AD8 /* CarbStore+SimulatedCoreData.swift */,
 				C17824991E1999FA00D9D25C /* CaseCountable.swift */,
@@ -2400,6 +2411,7 @@
 				43F64DD81D9C92C900D24DC6 /* TitleSubtitleTableViewCell.swift */,
 				4311FB9A1F37FE1B00D4C0A7 /* TitleSubtitleTextFieldTableViewCell.swift */,
 				C1AF062229426300002C1B19 /* ManualGlucoseEntryRow.swift */,
+				DDC389FD2A2C4C830066E2E8 /* GlucoseBasedApplicationFactorSelectionView.swift */,
 			);
 			path = Views;
 			sourceTree = "<group>";
@@ -2441,6 +2453,9 @@
 				C1F2075B26D6F9B0007AB7EB /* ProfileExpirationAlerter.swift */,
 				A96DAC2B2838F31200D94E38 /* SharedLogging.swift */,
 				7E69CFFB2A16A77E00203CBD /* ResetLoopManager.swift */,
+				DDC389F52A2B61750066E2E8 /* ApplicationFactorStrategy.swift */,
+				DDC389F72A2B620B0066E2E8 /* GlucoseBasedApplicationFactorStrategy.swift */,
+				DDC389F92A2B62470066E2E8 /* ConstantApplicationFactorStrategy.swift */,
 			);
 			path = Managers;
 			sourceTree = "<group>";
@@ -3872,6 +3887,7 @@
 				C1201E2C23ECDBD0002DA84A /* WatchContextRequestUserInfo.swift in Sources */,
 				1D49795824E7289700948F05 /* ServicesViewModel.swift in Sources */,
 				1D4A3E2D2478628500FD601B /* StoredAlert+CoreDataClass.swift in Sources */,
+				DDC389FA2A2B62470066E2E8 /* ConstantApplicationFactorStrategy.swift in Sources */,
 				892D7C5123B54A15008A9656 /* CarbEntryViewController.swift in Sources */,
 				B4E202302661063E009421B5 /* AutomaticDosingStatus.swift in Sources */,
 				C191D2A125B3ACAA00C26C0B /* DosingStrategySelectionView.swift in Sources */,
@@ -3903,6 +3919,7 @@
 				1DB619AC270BAD3D006C9D07 /* VersionUpdateViewModel.swift in Sources */,
 				A9C62D882331703100535612 /* Service.swift in Sources */,
 				89CAB36324C8FE96009EE3CE /* PredictedGlucoseChartView.swift in Sources */,
+				DDC389F82A2B620B0066E2E8 /* GlucoseBasedApplicationFactorStrategy.swift in Sources */,
 				4F6663941E905FD2009E74FC /* ChartColorPalette+Loop.swift in Sources */,
 				A9F703732489BC8500C98AD8 /* CarbStore+SimulatedCoreData.swift in Sources */,
 				4328E0351CFC0AE100E199AA /* WatchDataManager.swift in Sources */,
@@ -3933,6 +3950,7 @@
 				E9B080B1253BDA6300BAD8F8 /* UserDefaults+LoopIntents.swift in Sources */,
 				C1AF062329426300002C1B19 /* ManualGlucoseEntryRow.swift in Sources */,
 				C148CEE724FD91BD00711B3B /* DeliveryUncertaintyAlertManager.swift in Sources */,
+				DDC389FC2A2BC6670066E2E8 /* SettingsView+algorithmExperimentsSection.swift in Sources */,
 				1D12D3B92548EFDD00B53E8B /* main.swift in Sources */,
 				435400341C9F878D00D5819C /* SetBolusUserInfo.swift in Sources */,
 				A9DCF32A25B0FABF00C89088 /* LoopUIColorPalette+Default.swift in Sources */,
@@ -3967,13 +3985,15 @@
 				A97F250825E056D500F0EE19 /* OnboardingManager.swift in Sources */,
 				438D42F91D7C88BC003244B0 /* PredictionInputEffect.swift in Sources */,
 				892A5D692230C41D008961AB /* RangeReplaceableCollection.swift in Sources */,
+				DDC389F62A2B61750066E2E8 /* ApplicationFactorStrategy.swift in Sources */,
 				4F70C2101DE8FAC5006380B7 /* ExtensionDataManager.swift in Sources */,
 				43DFB62320D4CAE7008A7BAE /* PumpManager.swift in Sources */,
 				A9FB75F1252BE320004C7D3F /* BolusDosingDecision.swift in Sources */,
 				892A5D59222F0A27008961AB /* Debug.swift in Sources */,
 				431A8C401EC6E8AB00823B9C /* CircleMaskView.swift in Sources */,
 				1D05219D2469F1F5000EBBDE /* AlertStore.swift in Sources */,
 				439897371CD2F80600223065 /* AnalyticsServicesManager.swift in Sources */,
+				DDC389FE2A2C4C830066E2E8 /* GlucoseBasedApplicationFactorSelectionView.swift in Sources */,
 				A9C62D842331700E00535612 /* DiagnosticLog+Subsystem.swift in Sources */,
 				895FE0952201234000FCF18A /* OverrideSelectionViewController.swift in Sources */,
 				C1EF747228D6A44A00C8C083 /* CrashRecoveryManager.swift in Sources */,

Loop/Extensions/SettingsView+algorithmExperimentsSection.swift

@@ -0,0 +1,67 @@
+//
+//  SettingsView+algorithmExperimentsSection.swift
+//  Loop
+//
+//  Created by Jonas Björkert on 2023-06-03.
+//  Copyright © 2023 LoopKit Authors. All rights reserved.
+//
+
+import Foundation
+import SwiftUI
+import LoopKit
+import LoopKitUI
+
+extension SettingsView {
+    internal var algorithmExperimentsSection: some View {
+        NavigationLink(NSLocalizedString("Algorithm Experiments", comment: "The title of the Algorithm Experiments section in settings")) {
+            ExperimentsSettingsView(automaticDosingStrategy: viewModel.automaticDosingStrategy)
+        }
+    }
+}
+
+public struct ExperimentRow: View {
+    var name: String
+    var enabled: Bool
+
+    public var body: some View {
+        HStack {
+            Text(name)
+                .foregroundColor(.primary)
+            Spacer()
+            Text(enabled ? "On" : "Off")
+                .foregroundColor(enabled ? .red : .secondary)
+        }
+    }
+}
+
+public struct ExperimentsSettingsView: View {
+    @State private var isGlucoseBasedApplicationFactorEnabled = UserDefaults.standard.glucoseBasedApplicationFactorEnabled
+    var automaticDosingStrategy: AutomaticDosingStrategy
+
+    public var body: some View {
+        VStack(alignment: .center, spacing: 12) {
+            VStack {
+                Text("⚠️").font(.largeTitle)
+                Text("Caution")
+            }
+            Divider()
+            VStack(alignment: .leading, spacing: 12) {
+                Text(NSLocalizedString("Algorithm Experiments are optional modifications to the Loop Algorithm. These modifications are less tested than the standard Loop algorithm, so please use carefully.", comment: "Algorithm Experiments description."))
+                Text(NSLocalizedString("In future versions of Loop these experiments may change, end up as standard parts of the Loop Algorithm, or be removed from Loop entirely. Please follow along in the Loop Zulip chat to stay informed of possible changes to these features.", comment: "Algorithm Experiments description second paragraph."))
+            }
+            .foregroundColor(.secondary)
+
+            Divider()
+            NavigationLink(destination: GlucoseBasedApplicationFactorSelectionView(isGlucoseBasedApplicationFactorEnabled: $isGlucoseBasedApplicationFactorEnabled, automaticDosingStrategy: automaticDosingStrategy)) {
+                ExperimentRow(name: "Glucose Based Partial Application", enabled: isGlucoseBasedApplicationFactorEnabled && automaticDosingStrategy == .automaticBolus)
+            }
+            .padding()
+            .background(Color(UIColor.secondarySystemBackground))
+            .foregroundColor(.accentColor)
+            .cornerRadius(10)
+            Spacer()
+        }
+        .padding()
+        .navigationTitle(NSLocalizedString("Algorithm Experiments", comment: "Navigation title for algorithms experiments screen"))
+    }
+}

Loop/Managers/ApplicationFactorStrategy.swift

@@ -0,0 +1,20 @@
+//
+//  ApplicationFactorStrategy.swift
+//  Loop
+//
+//  Created by Jonas Björkert on 2023-06-03.
+//  Copyright © 2023 LoopKit Authors. All rights reserved.
+//
+
+import Foundation
+import HealthKit
+import LoopKit
+import LoopCore
+
+protocol ApplicationFactorStrategy {
+    func calculateDosingFactor(
+        for glucose: HKQuantity,
+        correctionRangeSchedule: GlucoseRangeSchedule,
+        settings: LoopSettings
+    ) -> Double
+}

Loop/Managers/ConstantApplicationFactorStrategy.swift

@@ -0,0 +1,23 @@
+//
+//  ConstantDosingStrategy.swift
+//  Loop
+//
+//  Created by Jonas Björkert on 2023-06-03.
+//  Copyright © 2023 LoopKit Authors. All rights reserved.
+//
+
+import Foundation
+import HealthKit
+import LoopKit
+import LoopCore
+
+struct ConstantApplicationFactorStrategy: ApplicationFactorStrategy {
+    func calculateDosingFactor(
+        for glucose: HKQuantity,
+        correctionRangeSchedule: GlucoseRangeSchedule,
+        settings: LoopSettings
+    ) -> Double {
+        // The original strategy uses a constant dosing factor.
+        return LoopConstants.bolusPartialApplicationFactor
+    }
+}

Loop/Managers/GlucoseBasedApplicationFactorStrategy.swift

@@ -0,0 +1,57 @@
+//
+//  GlucoseBasedApplicationFactorStrategy.swift
+//  Loop
+//
+//  Created by Jonas Björkert on 2023-06-03.
+//  Copyright © 2023 LoopKit Authors. All rights reserved.
+//
+
+import Foundation
+import HealthKit
+import LoopKit
+import LoopCore
+
+struct GlucoseBasedApplicationFactorStrategy: ApplicationFactorStrategy {
+    static let minPartialApplicationFactor = 0.20 // min fraction of correction when glucose > minGlucoseSlidingScale
+    static let maxPartialApplicationFactor = 0.80 // max fraction of correction when glucose > maxGlucoseSlidingScale
+    // set minGlucoseSlidingScale based on user setting for correction range
+    // use mg/dL for calculations
+    static let minGlucoseDeltaSlidingScale = 10.0 // mg/dL
+    static let maxGlucoseSlidingScale = 200.0 // mg/dL
+
+    func calculateDosingFactor(
+        for glucose: HKQuantity,
+        correctionRangeSchedule: GlucoseRangeSchedule,
+        settings: LoopSettings
+    ) -> Double {
+        // Calculate current glucose and lower bound target
+        let currentGlucose = glucose.doubleValue(for: .milligramsPerDeciliter)
+        let correctionRange = correctionRangeSchedule.quantityRange(at: Date())
+        let lowerBoundTarget = correctionRange.lowerBound.doubleValue(for: .milligramsPerDeciliter)
+
+        // Calculate minimum glucose sliding scale and scaling fraction
+        let minGlucoseSlidingScale = GlucoseBasedApplicationFactorStrategy.minGlucoseDeltaSlidingScale + lowerBoundTarget
+        let scalingFraction = (GlucoseBasedApplicationFactorStrategy.maxPartialApplicationFactor - GlucoseBasedApplicationFactorStrategy.minPartialApplicationFactor) / (GlucoseBasedApplicationFactorStrategy.maxGlucoseSlidingScale - minGlucoseSlidingScale)
+        let scalingGlucose = max(currentGlucose - minGlucoseSlidingScale, 0.0)
+
+        // Calculate effectiveBolusApplicationFactor
+        let effectiveBolusApplicationFactor = min(GlucoseBasedApplicationFactorStrategy.minPartialApplicationFactor + scalingGlucose * scalingFraction, GlucoseBasedApplicationFactorStrategy.maxPartialApplicationFactor)
+
+        return effectiveBolusApplicationFactor
+    }
+}
+
+extension UserDefaults {
+    private enum Key: String {
+        case GlucoseBasedApplicationFactorEnabled = "com.loopkit.algorithmExperiments.glucoseBasedApplicationFactorEnabled"
+    }
+
+    var glucoseBasedApplicationFactorEnabled: Bool {
+        get {
+            bool(forKey: Key.GlucoseBasedApplicationFactorEnabled.rawValue) as Bool
+        }
+        set {
+            set(newValue, forKey: Key.GlucoseBasedApplicationFactorEnabled.rawValue)
+        }
+    }
+}

Loop/Managers/LoopDataManager.swift

@@ -1698,7 +1698,23 @@ extension LoopDataManager {
                     return self.delegate?.roundBolusVolume(units: units) ?? units
                 }
 
-                let maxAutomaticBolus = min(iobHeadroom, maxBolus! * LoopConstants.bolusPartialApplicationFactor)
+                // Create dosing strategy based on user setting
+                let applicationFactorStrategy: ApplicationFactorStrategy = UserDefaults.standard.glucoseBasedApplicationFactorEnabled
+                    ? GlucoseBasedApplicationFactorStrategy()
+                    : ConstantApplicationFactorStrategy()
+
+                let correctionRangeSchedule = settings.effectiveGlucoseTargetRangeSchedule()
+
+                let effectiveBolusApplicationFactor = applicationFactorStrategy.calculateDosingFactor(
+                    for: glucose.quantity,
+                    correctionRangeSchedule: correctionRangeSchedule!,
+                    settings: settings
+                )
+
+                self.logger.debug(" *** Glucose: %{public}@, effectiveBolusApplicationFactor: %.2f", glucose.quantity.description, effectiveBolusApplicationFactor)
+
+                // If a user customizes maxPartialApplicationFactor > 1; this respects maxBolus
+                let maxAutomaticBolus = min(iobHeadroom, maxBolus! * min(effectiveBolusApplicationFactor, 1.0))
 
                 dosingRecommendation = predictedGlucose.recommendedAutomaticDose(
                     to: glucoseTargetRange!,
@@ -1708,7 +1724,7 @@ extension LoopDataManager {
                     model: doseStore.insulinModelProvider.model(for: pumpInsulinType),
                     basalRates: basalRateSchedule!,
                     maxAutomaticBolus: maxAutomaticBolus,
-                    partialApplicationFactor: LoopConstants.bolusPartialApplicationFactor * self.timeBasedDoseApplicationFactor,
+                    partialApplicationFactor: effectiveBolusApplicationFactor * self.timeBasedDoseApplicationFactor,
                     lastTempBasal: lastTempBasal,
                     volumeRounder: volumeRounder,
                     rateRounder: rateRounder,
@@ -2128,6 +2144,7 @@ extension LoopDataManager {
                 "insulinOnBoard: \(String(describing: manager.insulinOnBoard))",
                 "error: \(String(describing: state.error))",
                 "overrideInUserDefaults: \(String(describing: UserDefaults.appGroup?.intentExtensionOverrideToSet))",
+                "glucoseBasedApplicationFactorEnabled: \(UserDefaults.standard.glucoseBasedApplicationFactorEnabled)",
                 "",
                 String(reflecting: self.retrospectiveCorrection),
                 "",