Choose the sync identifier for each new carb entry

Loop.xcodeproj/project.pbxproj

@@ -387,6 +387,7 @@
 		A9F703752489C9A000C98AD8 /* GlucoseStore+SimulatedCoreData.swift in Sources */ = {isa = PBXBuildFile; fileRef = A9F703742489C9A000C98AD8 /* GlucoseStore+SimulatedCoreData.swift */; };
 		A9F703772489D8AA00C98AD8 /* PersistentDeviceLog+SimulatedCoreData.swift in Sources */ = {isa = PBXBuildFile; fileRef = A9F703762489D8AA00C98AD8 /* PersistentDeviceLog+SimulatedCoreData.swift */; };
 		A9FB75F1252BE320004C7D3F /* BolusDosingDecision.swift in Sources */ = {isa = PBXBuildFile; fileRef = A9FB75F0252BE320004C7D3F /* BolusDosingDecision.swift */; };
+		2437A340C1560EEDE55E3F7B /* CarbEntryChange.swift in Sources */ = {isa = PBXBuildFile; fileRef = 8378B7D1F532A5F47CEBB6AE /* CarbEntryChange.swift */; };
 		B4001CEE28CBBC82002FB414 /* AlertManagementView.swift in Sources */ = {isa = PBXBuildFile; fileRef = B4001CED28CBBC82002FB414 /* AlertManagementView.swift */; };
 		A1E47000000000000000A001 /* AlertHistoryView.swift in Sources */ = {isa = PBXBuildFile; fileRef = A1E47000000000000000A002 /* AlertHistoryView.swift */; };
 		B405E35A24D2B1A400DD058D /* HUDAssets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = 4F2C15961E09E94E00E160D4 /* HUDAssets.xcassets */; };
@@ -1199,6 +1200,7 @@
 		A9F703742489C9A000C98AD8 /* GlucoseStore+SimulatedCoreData.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "GlucoseStore+SimulatedCoreData.swift"; sourceTree = "<group>"; };
 		A9F703762489D8AA00C98AD8 /* PersistentDeviceLog+SimulatedCoreData.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "PersistentDeviceLog+SimulatedCoreData.swift"; sourceTree = "<group>"; };
 		A9FB75F0252BE320004C7D3F /* BolusDosingDecision.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BolusDosingDecision.swift; sourceTree = "<group>"; };
+		8378B7D1F532A5F47CEBB6AE /* CarbEntryChange.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CarbEntryChange.swift; sourceTree = "<group>"; };
 		AF16A5EDEB9DF756890E0C09 /* Loop/Resources/Sounds/bloop.caf */ = {isa = PBXFileReference; lastKnownFileType = file; path = Loop/Resources/Sounds/bloop.caf; sourceTree = SOURCE_ROOT; };
 		B4001CED28CBBC82002FB414 /* AlertManagementView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AlertManagementView.swift; sourceTree = "<group>"; };
 		A1E47000000000000000A002 /* AlertHistoryView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AlertHistoryView.swift; sourceTree = "<group>"; };
@@ -1708,6 +1710,7 @@
 				DDC389F52A2B61750066E2E8 /* ApplicationFactorStrategy.swift */,
 				FEEDF0000000000000000000 /* GlucoseStatistics.swift */,
 				A9FB75F0252BE320004C7D3F /* BolusDosingDecision.swift */,
+				8378B7D1F532A5F47CEBB6AE /* CarbEntryChange.swift */,
 				DDC389F92A2B62470066E2E8 /* ConstantApplicationFactorStrategy.swift */,
 				C1EF747128D6A44A00C8C083 /* CrashRecoveryManager.swift */,
 				1455ACB12C667BEE004F44F2 /* Deeplink.swift */,
@@ -3636,6 +3639,7 @@
 				1455ACB22C667BEE004F44F2 /* Deeplink.swift in Sources */,
 				43DFB62320D4CAE7008A7BAE /* PumpManager.swift in Sources */,
 				A9FB75F1252BE320004C7D3F /* BolusDosingDecision.swift in Sources */,
+				2437A340C1560EEDE55E3F7B /* CarbEntryChange.swift in Sources */,
 				892A5D59222F0A27008961AB /* Debug.swift in Sources */,
 				431A8C401EC6E8AB00823B9C /* CircleMaskView.swift in Sources */,
 				1D05219D2469F1F5000EBBDE /* AlertStore.swift in Sources */,

Loop/Extensions/CarbStore+SimulatedCoreData.swift

@@ -61,6 +61,7 @@ extension CarbStore {
 fileprivate extension NewCarbEntry {
     static func simulated(startDate: Date, grams: Double, absorptionTime: TimeInterval) -> NewCarbEntry {
         return NewCarbEntry(date: startDate,
+                            syncIdentifier: UUID().uuidString,
                             quantity: LoopQuantity(unit: .gram, doubleValue: grams),
                             startDate: startDate,
                             foodType: "Simulated",

Loop/Managers/LoopAppManager.swift

@@ -976,7 +976,7 @@ extension LoopAppManager: UNUserNotificationCenterDelegate {
                 let mealTime = userInfo[LoopNotificationUserInfoKey.missedMealTime.rawValue] as? Date,
                 let carbAmount = userInfo[LoopNotificationUserInfoKey.missedMealCarbAmount.rawValue] as? Double
             {
-                let missedEntry = NewCarbEntry(quantity: LoopQuantity(unit: .gram,
+                let missedEntry = NewCarbEntry(syncIdentifier: UUID().uuidString, quantity: LoopQuantity(unit: .gram,
                                                                          doubleValue: carbAmount),
                                                     startDate: mealTime,
                                                     foodType: nil,

Loop/Managers/LoopDataManager.swift

@@ -808,14 +808,13 @@ final class LoopDataManager: ObservableObject {
 
     func recommendManualBolus(
         manualGlucoseSample: NewGlucoseSample? = nil,
-        potentialCarbEntry: NewCarbEntry? = nil,
-        originalCarbEntry: StoredCarbEntry? = nil,
+        carbEntryChange: CarbEntryChange? = nil,
         truncatingActiveOverride: Bool = false
     ) async throws -> ManualBolusRecommendation? {
 
         var endingPremealOverride = false
 
-        if potentialCarbEntry != nil,
+        if carbEntryChange != nil,
             let activeOverride = temporaryPresetsManager.activeOverride,
             activeOverride.context == .preMeal
         {
@@ -824,8 +823,8 @@ final class LoopDataManager: ObservableObject {
 
         var input = try await self.fetchData(for: now, presumePresetEndingNow: truncatingActiveOverride || endingPremealOverride)
             .addingGlucoseSample(sample: manualGlucoseSample?.asStoredGlucoseSample)
-            .removingCarbEntry(carbEntry: originalCarbEntry)
-            .addingCarbEntry(carbEntry: potentialCarbEntry?.asStoredCarbEntry)
+            .removingCarbEntry(carbEntry: carbEntryChange?.originalEntry)
+            .addingCarbEntry(carbEntry: carbEntryChange?.asStoredCarbEntry)
 
         input.includePositiveVelocityAndRC = usePositiveMomentumAndRCForManualBoluses
         input.recommendationType = .manualBolus
@@ -990,16 +989,15 @@ extension LoopDataManager {
     /// Adds and stores carb data, and recommends a bolus if needed
     ///
     /// - Parameters:
-    ///   - carbEntry: The new carb value
-    ///   - completion: A closure called once upon completion
-    ///   - result: The bolus recommendation
-    func addCarbEntry(_ carbEntry: NewCarbEntry, replacing replacingEntry: StoredCarbEntry? = nil) async throws -> StoredCarbEntry {
-        let storedCarbEntry: StoredCarbEntry
-        if let replacingEntry = replacingEntry {
-            storedCarbEntry = try await carbStore.replaceCarbEntry(replacingEntry, withEntry: carbEntry)
-        } else {
-            storedCarbEntry = try await carbStore.addCarbEntry(carbEntry)
-        }
+    ///   - carbEntry: The new carb value, stored once however often it is retried
+    func addCarbEntry(_ carbEntry: NewCarbEntry) async throws -> StoredCarbEntry {
+        let storedCarbEntry = try await carbStore.addCarbEntry(carbEntry)
+        self.temporaryPresetsManager.endPreMealOverride()
+        return storedCarbEntry
+    }
+
+    func replaceCarbEntry(_ oldEntry: StoredCarbEntry, with update: CarbEntryUpdate) async throws -> StoredCarbEntry {
+        let storedCarbEntry = try await carbStore.replaceCarbEntry(oldEntry, withEntry: update)
         self.temporaryPresetsManager.endPreMealOverride()
         return storedCarbEntry
     }
@@ -1203,6 +1201,18 @@ extension NewCarbEntry {
     }
 }
 
+extension CarbEntryUpdate {
+    var asStoredCarbEntry: StoredCarbEntry {
+        StoredCarbEntry(
+            startDate: startDate,
+            quantity: quantity,
+            foodType: foodType,
+            absorptionTime: absorptionTime,
+            userCreatedDate: date
+        )
+    }
+}
+
 extension NewGlucoseSample {
     var asStoredGlucoseSample: StoredGlucoseSample {
         StoredGlucoseSample(
@@ -1386,7 +1396,7 @@ extension LoopDataManager: ServicesManagerDelegate {
         }
 
         let quantity = LoopQuantity(unit: .gram, doubleValue: amountInGrams)
-        let candidateCarbEntry = NewCarbEntry(quantity: quantity, startDate: startDate ?? now, foodType: foodType, absorptionTime: absorptionTime)
+        let candidateCarbEntry = NewCarbEntry(syncIdentifier: UUID().uuidString, quantity: quantity, startDate: startDate ?? now, foodType: foodType, absorptionTime: absorptionTime)
 
         let _ = try await carbStore.addCarbEntry(candidateCarbEntry)
     }
@@ -1473,15 +1483,14 @@ extension LoopDataManager: BolusEntryViewModelDelegate {
     }
 
     func generatePrediction(
-        originalCarbEntry: StoredCarbEntry?,
-        potentialCarbEntry: NewCarbEntry?,
+        carbEntryChange: CarbEntryChange?,
         potentialDose: SimpleInsulinDose?,
         manualGlucose: NewGlucoseSample?
     ) async throws -> (historicGlucose: [StoredGlucoseSample], predictedGlucose: [PredictedGlucoseValue]) {
 
         var endingPremealOverride = false
 
-        if potentialCarbEntry != nil,
+        if carbEntryChange != nil,
             let activeOverride = temporaryPresetsManager.activeOverride,
             activeOverride.context == .preMeal
         {
@@ -1494,8 +1503,8 @@ extension LoopDataManager: BolusEntryViewModelDelegate {
         input = input
             .addingDose(dose: potentialDose)
             .addingGlucoseSample(sample: manualGlucose?.asStoredGlucoseSample)
-            .removingCarbEntry(carbEntry: originalCarbEntry)
-            .addingCarbEntry(carbEntry: potentialCarbEntry?.asStoredCarbEntry)
+            .removingCarbEntry(carbEntry: carbEntryChange?.originalEntry)
+            .addingCarbEntry(carbEntry: carbEntryChange?.asStoredCarbEntry)
 
         let prediction = try input.predictGlucose()
 

Loop/Managers/Store Protocols/CarbStoreProtocol.swift

@@ -12,7 +12,7 @@ protocol CarbStoreProtocol: AnyObject {
 
     func getCarbEntries(start: Date?, end: Date?, dateAscending: Bool, fetchLimit: Int?, with favoriteFoodID: String?) async throws -> [StoredCarbEntry]
 
-    func replaceCarbEntry(_ oldEntry: StoredCarbEntry, withEntry newEntry: NewCarbEntry) async throws -> StoredCarbEntry
+    func replaceCarbEntry(_ oldEntry: StoredCarbEntry, withEntry newEntry: CarbEntryUpdate) async throws -> StoredCarbEntry
 
     func addCarbEntry(_ entry: NewCarbEntry) async throws -> StoredCarbEntry
 

Loop/Managers/WatchDataManager.swift

@@ -307,8 +307,7 @@ final class WatchDataManager: NSObject {
 
         if let recommendedBolus = try? await loopDataManager.recommendManualBolus(
             manualGlucoseSample: nil,
-            potentialCarbEntry: potentialCarbEntry,
-            originalCarbEntry: nil
+            carbEntryChange: potentialCarbEntry.map { .add($0) }
         ) {
             context.recommendedBolusDose = recommendedBolus.amount
             dosingDecision.manualBolusRecommendation = ManualBolusRecommendationWithDate(

Loop/Models/CarbEntryChange.swift

@@ -0,0 +1,58 @@
+//
+//  CarbEntryChange.swift
+//  Loop
+//
+//  Copyright © 2026 LoopKit Authors. All rights reserved.
+//
+
+import Foundation
+import LoopAlgorithm
+import LoopKit
+
+/// A carb entry about to be saved: a new entry, or new content for a stored one.
+enum CarbEntryChange: Equatable {
+    case add(NewCarbEntry)
+    case edit(StoredCarbEntry, CarbEntryUpdate)
+
+    var originalEntry: StoredCarbEntry? {
+        if case .edit(let original, _) = self {
+            return original
+        }
+        return nil
+    }
+
+    var quantity: LoopQuantity {
+        switch self {
+        case .add(let entry): entry.quantity
+        case .edit(_, let update): update.quantity
+        }
+    }
+
+    var startDate: Date {
+        switch self {
+        case .add(let entry): entry.startDate
+        case .edit(_, let update): update.startDate
+        }
+    }
+
+    var foodType: String? {
+        switch self {
+        case .add(let entry): entry.foodType
+        case .edit(_, let update): update.foodType
+        }
+    }
+
+    var absorptionTime: TimeInterval? {
+        switch self {
+        case .add(let entry): entry.absorptionTime
+        case .edit(_, let update): update.absorptionTime
+        }
+    }
+
+    var asStoredCarbEntry: StoredCarbEntry {
+        switch self {
+        case .add(let entry): entry.asStoredCarbEntry
+        case .edit(_, let update): update.asStoredCarbEntry
+        }
+    }
+}