Configurable future carbs limit for Loop remote carbs

LoopFollow/Remote/LoopAPNS/LoopAPNSCarbsView.swift

@@ -9,6 +9,7 @@ struct LoopAPNSCarbsView: View {
 
     @Environment(\.presentationMode) var presentationMode
     @ObservedObject private var quickPickMeals = QuickPickMealsManager.shared
+    @ObservedObject private var maxFutureCarbHours = Storage.shared.loopMaxFutureCarbHours
     @State private var carbsAmount = HKQuantity(unit: .gram(), doubleValue: 0.0)
     @State private var absorptionHours = 3
     @State private var absorptionMinutes = 0
@@ -25,12 +26,15 @@ struct LoopAPNSCarbsView: View {
     private let otpPeriod: TimeInterval = 30
     private let timeAdjustmentStepMinutes = 5
     private let maxPastHours = 12
-    private let maxFutureHours = 1
     private let minAllowedAbsorptionTime = 0.5
     private let maxAllowedAbsorptionTime = 8.0
     private let lollipopStandardAbsorption: AbsorptionPreset = (0, 30)
     private let tacoStandardAbsorption: AbsorptionPreset = (3, 0)
     private let pizzaStandardAbsorption: AbsorptionPreset = (5, 0)
+    private var maxFutureHours: Int {
+        maxFutureCarbHours.value
+    }
+
     private var otpTimer = Timer.publish(every: 1, on: .main, in: .common).autoconnect()
 
     @FocusState private var carbsFieldIsFocused: Bool
@@ -516,7 +520,7 @@ struct LoopAPNSCarbsView: View {
         }
 
         if consumedDate > latestAcceptedDate {
-            alertMessage = "Time must be within the next \(maxFutureHours) hour"
+            alertMessage = "Time must be within the next \(maxFutureHours) \(maxFutureHours == 1 ? "hour" : "hours")"
             alertType = .error
             showAlert = true
             return

LoopFollow/Remote/LoopAPNS/LoopCarbEditSheet.swift

@@ -19,7 +19,10 @@ struct LoopCarbEditSheet: View {
     @FocusState private var carbsFocused: Bool
 
     private let maxPastHours = 12
-    private let maxFutureHours = 1
+    private var maxFutureHours: Int {
+        Storage.shared.loopMaxFutureCarbHours.value
+    }
+
     private let minAbsorptionHours = 0.5
     private let maxAbsorptionHours = 8
 

LoopFollow/Remote/Settings/RemoteSettingsView.swift

@@ -10,6 +10,7 @@ struct RemoteSettingsView: View {
     @ObservedObject private var device = Storage.shared.device
     @ObservedObject var bolusIncrement = Storage.shared.bolusIncrement
     @ObservedObject private var watchRemoteCommands = Storage.shared.watchRemoteCommands
+    @ObservedObject private var loopMaxFutureCarbHours = Storage.shared.loopMaxFutureCarbHours
 
     @State private var showAlert: Bool = false
     @State private var alertType: AlertType? = nil
@@ -90,6 +91,19 @@ struct RemoteSettingsView: View {
                 }
             }
 
+            if viewModel.remoteType == .loopAPNS {
+                Section(
+                    header: Text("Meal Settings"),
+                    footer: Text("How far ahead carbs can be entered. Loop accepts up to 1 hr; use 4 hr if Loop is built with the future_carbs_4h customization.")
+                ) {
+                    Picker("Max Future Carbs", selection: $loopMaxFutureCarbHours.value) {
+                        ForEach(1 ... 4, id: \.self) { hours in
+                            Text("\(hours) hr").tag(hours)
+                        }
+                    }
+                }
+            }
+
             // MARK: - Guardrails Section (shown for both TRC and Loop)
 
             if viewModel.remoteType == .trc || viewModel.remoteType == .loopAPNS {

LoopFollow/Settings/ImportExport/ExportableSettings.swift

@@ -242,6 +242,7 @@ struct RemoteSettingsExport: Codable {
     let mealWithFatProtein: Bool
     let productionEnvironment: Bool
     let loopAPNSQrCodeURL: String
+    let loopMaxFutureCarbHours: Int?
     let device: String
 
     static func fromCurrentStorage() -> RemoteSettingsExport {
@@ -262,6 +263,7 @@ struct RemoteSettingsExport: Codable {
             mealWithFatProtein: storage.mealWithFatProtein.value,
             productionEnvironment: storage.productionEnvironment.value,
             loopAPNSQrCodeURL: storage.loopAPNSQrCodeURL.value,
+            loopMaxFutureCarbHours: storage.loopMaxFutureCarbHours.value,
             device: storage.device.value
         )
     }
@@ -283,6 +285,9 @@ struct RemoteSettingsExport: Codable {
         storage.mealWithFatProtein.value = mealWithFatProtein
         storage.productionEnvironment.value = productionEnvironment
         storage.loopAPNSQrCodeURL.value = loopAPNSQrCodeURL
+        if let loopMaxFutureCarbHours {
+            storage.loopMaxFutureCarbHours.value = loopMaxFutureCarbHours
+        }
 
         // Set device temporarily from import (will be overridden by Nightscout connection)
         if !device.isEmpty {

LoopFollow/Storage/Storage.swift

@@ -257,6 +257,7 @@ class Storage {
     var treatmentsPosition = StorageValue<TabPosition>(key: "treatmentsPosition", defaultValue: .menu)
 
     var loopAPNSQrCodeURL = StorageValue<String>(key: "loopAPNSQrCodeURL", defaultValue: "")
+    var loopMaxFutureCarbHours = StorageValue<Int>(key: "loopMaxFutureCarbHours", defaultValue: 1)
 
     var bolusIncrement = SecureStorageValue<HKQuantity>(key: "bolusIncrement", defaultValue: HKQuantity(unit: .internationalUnit(), doubleValue: 0.05))
     var bolusIncrementDetected = StorageValue<Bool>(key: "bolusIncrementDetected", defaultValue: false)

LoopFollow/Treatments/LoopCarbTreatment.swift

@@ -45,9 +45,9 @@ struct LoopCarbTreatment: Codable, Equatable {
         absorptionMinutes.map { $0 / 60 }
     }
 
-    func isWithinEditWindow(now: Date = Date()) -> Bool {
+    func isWithinEditWindow(now: Date = Date(), maxFutureHours: Int = Storage.shared.loopMaxFutureCarbHours.value) -> Bool {
         let age = now.timeIntervalSince1970 - date
-        return age <= Self.editWindow && age >= -3600
+        return age <= Self.editWindow && age >= -TimeInterval(maxFutureHours) * 3600
     }
 
     /// Loop APNS targets a Loop device, whatever commands that build advertises.

LoopFollow/Treatments/TreatmentsView.swift

@@ -687,7 +687,9 @@ struct TreatmentDetailView: View {
     }
 
     private func loopRemoteActionsFooter(withinWindow: Bool) -> Text? {
-        withinWindow ? nil : Text("Carb entries can be changed remotely for 23 hours.")
+        guard !withinWindow else { return nil }
+        let futureHours = Storage.shared.loopMaxFutureCarbHours.value
+        return Text("Carb entries can be changed remotely up to 23 hours after and \(futureHours) \(futureHours == 1 ? "hour" : "hours") before their time.")
     }
 
     @ViewBuilder

Tests/LoopCarbTreatmentTests.swift

@@ -39,16 +39,18 @@ struct LoopCarbTreatmentTests {
         #expect(LoopCarbTreatment(nightscoutEntry: entry(carbs: 0), date: 0) == nil)
     }
 
-    @Test("edit window is 23 h back and 1 h ahead")
+    @Test("edit window is 23 h back and the max future carbs setting ahead")
     func window() {
         let now = Date(timeIntervalSince1970: 1_700_000_000)
         func carb(offsetHours: Double) -> LoopCarbTreatment? {
             LoopCarbTreatment(nightscoutEntry: entry(), date: now.timeIntervalSince1970 + offsetHours * 3600)
         }
-        #expect(carb(offsetHours: -22)?.isWithinEditWindow(now: now) == true)
-        #expect(carb(offsetHours: -24)?.isWithinEditWindow(now: now) == false)
-        #expect(carb(offsetHours: 0.5)?.isWithinEditWindow(now: now) == true)
-        #expect(carb(offsetHours: 2)?.isWithinEditWindow(now: now) == false)
+        #expect(carb(offsetHours: -22)?.isWithinEditWindow(now: now, maxFutureHours: 1) == true)
+        #expect(carb(offsetHours: -24)?.isWithinEditWindow(now: now, maxFutureHours: 1) == false)
+        #expect(carb(offsetHours: 0.5)?.isWithinEditWindow(now: now, maxFutureHours: 1) == true)
+        #expect(carb(offsetHours: 2)?.isWithinEditWindow(now: now, maxFutureHours: 1) == false)
+        #expect(carb(offsetHours: 3.8)?.isWithinEditWindow(now: now, maxFutureHours: 4) == true)
+        #expect(carb(offsetHours: 4.5)?.isWithinEditWindow(now: now, maxFutureHours: 4) == false)
     }
 
     @Test("actions need Loop APNS, a Loop device and both commands advertised")