Very rough outlining for determine basal WIP

Trio.xcodeproj/project.pbxproj

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Trio/Sources/APS/OpenAPSSwift/DetermineBasal/DetermineBasalGenerator.swift

@@ -0,0 +1,50 @@
+import Foundation
+
+struct DeterminationRequest {
+    let glucose:        [BloodGlucose]
+    let pumpHistory:    [PumpHistoryEvent]
+    let carbTreatments: [MealInput]
+    let currentTemp:    TempBasal
+    let preferences:    Preferences
+    let custom:         TrioCustomOrefVariables
+    let date:           Date
+}
+
+protocol SMBProvider {
+    func isSMBEnabled(
+        glucose: BloodGlucose,
+        profile: Profile,
+        autosens: Autosens,
+        date: Date
+    ) -> Bool
+    
+    // TODO: handle oref JS's enable_smb() logic
+}
+
+struct DeterminationGenerator {
+    let profileGenerator: ProfileGenerator
+    let iobGenerator: IobGenerator
+    let autosensGenerator: AutosensGenerator
+    let mealProcessor: MealTotal
+    let smbProvider: SMBProvider
+
+    func generate(
+        request _: DeterminationRequest
+    ) throws -> Determination? {
+        
+        // FIXME: implement... (return type will not be Optional; just to shut up the compiler)
+        
+        /// Current determine basal (if we ignore forecasting logic; already modularized) does:
+        /// 1. Validate CGM → cancel if needed
+        /// 2. Override basal → log
+        /// 3. Load targets → error if missing
+        /// 4. Adjust sensitivity → maybe adjust basal/target
+        /// 5. Check IOB consistency → cancel if needed
+        /// 6. Compute deviation/eventualBG → log
+        /// 7. Ignore Forecast & but guard-BG
+        /// 8. Compute carbsReq → we could move this to MEAL
+        /// 9. Decide temp basal → we could do a tempBasalGenerator ?
+        
+        nil
+    }
+}

Trio/Sources/APS/OpenAPSSwift/Forecasts/ForecastGenerator.swift

@@ -0,0 +1,73 @@
+/// The top-level orchestrator
+struct ForecastGenerator {
+    let iob: SingleForecasting
+    let cob: SingleForecasting
+    let uam: SingleForecasting
+    let zt: SingleForecasting
+
+    init(
+        iob: SingleForecasting = IOBForecastGenerator(),
+        cob: SingleForecasting = COBForecastGenerator(),
+        uam: SingleForecasting = UAMForecastGenerator(),
+        zt: SingleForecasting = ZTForecastGenerator()
+    ) {
+        self.iob = iob
+        self.cob = cob
+        self.uam = uam
+        self.zt = zt
+    }
+
+    public func generate(
+        glucose: Double,
+        glucoseImpactSeries: [Double],
+        mealData: ComputedCarbs,
+        profile: Profile
+    ) -> ForecastResult {
+        let carbImpact = Double(mealData.currentDeviation) * Double(profile.carbRatio!) / Double(profile.sens!)
+        let deviation = mealData.currentDeviation
+
+        return ForecastResult(
+            iob: iob.forecast(
+                startingGlucose: glucose,
+                glucoseImpactSeries: glucoseImpactSeries,
+                mealData: mealData,
+                profile: profile,
+                carbImpact: carbImpact,
+                deviation: Double(deviation)
+            ),
+            cob: cob.forecast(
+                startingGlucose: glucose,
+                glucoseImpactSeries: glucoseImpactSeries,
+                mealData: mealData,
+                profile: profile,
+                carbImpact: carbImpact,
+                deviation: Double(deviation)
+            ),
+            uam: uam.forecast(
+                startingGlucose: glucose,
+                glucoseImpactSeries: glucoseImpactSeries,
+                mealData: mealData,
+                profile: profile,
+                carbImpact: carbImpact,
+                deviation: Double(deviation)
+            ),
+            zt: zt.forecast(
+                startingGlucose: glucose,
+                glucoseImpactSeries: glucoseImpactSeries,
+                mealData: mealData,
+                profile: profile,
+                carbImpact: carbImpact,
+                deviation: Double(deviation)
+            )
+        )
+    }
+
+    /// Trims trailing flat-line points beyond a “lookback” count
+    public static func trimFlatTails(_ series: [Double], lookback: Int) -> [Double] {
+        var s = series
+        while s.count > lookback, s.suffix(2)[0] == s.suffix(2)[1] {
+            s.removeLast()
+        }
+        return s
+    }
+}

Trio/Sources/APS/OpenAPSSwift/Forecasts/SingleForecasting.swift

@@ -0,0 +1,134 @@
+/// Common interface for a single forecast pipeline
+protocol SingleForecasting {
+    /// - Parameters:
+    ///   - startingGlucose: the current glucose
+    ///   - glucoseImpactSeries:  the series of BGI (insulin effect) ticks
+    ///   - mealData:   absorption & COB info
+    ///   - profile:    user profile (for carbRatio, DIA, etc)
+    ///   - carbImpact:         current carb impact (mg/dL per 5m)
+    ///   - deviation:  current deviation (mg/dL per 5m)
+    /// - Returns: a capped/clamped array of future BGs, one per 5-minute interval
+    func forecast(
+        startingGlucose: Double,
+        glucoseImpactSeries: [Double],
+        mealData: ComputedCarbs,
+        profile: Profile,
+        carbImpact: Double,
+        deviation: Double
+    ) -> [Double]
+}
+
+/// Forecast sub-generator for insulin-only effect (IOB)
+struct IOBForecastGenerator: SingleForecasting {
+    public func forecast(
+        startingGlucose: Double,
+        glucoseImpactSeries: [Double],
+        mealData _: ComputedCarbs,
+        profile _: Profile,
+        carbImpact _: Double,
+        deviation: Double
+    ) -> [Double] {
+        var result = [startingGlucose]
+        for (count, glucoseImpact) in glucoseImpactSeries.enumerated() {
+            let predDev = deviation * (1 - min(1, Double(count) / (60 / 5)))
+            let next = result.last! + glucoseImpact + predDev
+            result.append(next.clamp(lowerBound: 39, upperBound: 401))
+        }
+        return ForecastGenerator.trimFlatTails(result, lookback: 90 / 5)
+    }
+}
+
+/// Forecast sub-generator for carb-only effect (COB + UAM piece)
+struct COBForecastGenerator: SingleForecasting {
+    public func forecast(
+        startingGlucose: Double,
+        glucoseImpactSeries: [Double],
+        mealData _: ComputedCarbs,
+        profile: Profile,
+        carbImpact: Double,
+        deviation: Double
+    ) -> [Double] {
+        var result = [startingGlucose]
+
+        guard let sensitivity = profile.sens else {
+            fatalError("Profile must have a `sens` value")
+        }
+
+        guard let carbRatio = profile.carbRatio else {
+            fatalError("Profile must have a `carbRatio` value")
+        }
+
+        let carbSensivityFactor = Double(sensitivity) / Double(carbRatio)
+
+        // FIXME: compute these
+        let carbImpactDuration = 100
+        let remainingCarbImpactPeak = 100
+
+        for i in 1 ..< 48 {
+            let forecastedGlucoseImpact = glucoseImpactSeries[i]
+            // linear drop-off of carb impact over carbImpactDuration*2 intervals
+
+            let numerator = Double(carbImpact * (1 - Double(i)))
+            let denominator = Double(max(carbImpactDuration * 2, 1))
+            let rawDecay = numerator / denominator
+            let carbDecay = Double(max(0, rawDecay))
+
+            // add the "triangle" bump up to remainingCarbImpactPeak
+            let remainingCarbImpact = i < Int(carbImpactDuration * 2)
+                ? remainingCarbImpactPeak * (Int(Double(i)) / (carbImpactDuration * 2))
+                : 0
+
+            let next = result
+                .last! + Double(carbImpactDuration) + Double(min(0, deviation)) + carbDecay + Double(remainingCarbImpact)
+            result.append(next.clamp(lowerBound: 39, upperBound: 1500))
+        }
+
+        return ForecastGenerator.trimFlatTails(result, lookback: 12) // stop at plateau
+    }
+}
+
+/// Forecast sub-generator for “unannounced meal” impact (UAM)
+struct UAMForecastGenerator: SingleForecasting {
+    public func forecast(
+        startingGlucose: Double,
+        glucoseImpactSeries: [Double],
+        mealData: ComputedCarbs,
+        profile _: Profile,
+        carbImpact: Double,
+        deviation: Double
+    ) -> [Double] {
+        var result = [startingGlucose]
+
+        let slope = min(deviation, -(Double(mealData.slopeFromMinDeviation) / 3))
+        for i in 1 ..< 48 {
+            let forecastedGlucoseImpact = glucoseImpactSeries[i]
+            let forecastedUnannouncedCarbImpact = max(0, carbImpact + slope * Double(i))
+            let next = result.last! + forecastedGlucoseImpact + min(0, deviation) + forecastedUnannouncedCarbImpact
+            result.append(next.clamp(lowerBound: 39, upperBound: 401))
+        }
+
+        return ForecastGenerator.trimFlatTails(result, lookback: 12)
+    }
+}
+
+/// Forecast sub-generator for “zero-temp” baseline (ZT)
+struct ZTForecastGenerator: SingleForecasting {
+    public func forecast(
+        startingGlucose: Double,
+        glucoseImpactSeries: [Double],
+        mealData: ComputedCarbs,
+        profile: Profile,
+        carbImpact: Double,
+        deviation: Double
+    ) -> [Double] {
+        // essentially insulin effect only, but with zero-temp ISF if needed
+        IOBForecastGenerator().forecast(
+            startingGlucose: startingGlucose,
+            glucoseImpactSeries: glucoseImpactSeries.map { /* TODO: use iobWithZeroTemp.activity */ $0 },
+            mealData: mealData,
+            profile: profile,
+            carbImpact: carbImpact,
+            deviation: deviation
+        )
+    }
+}

Trio/Sources/APS/OpenAPSSwift/Models/ForecastResult.swift

@@ -0,0 +1,6 @@
+struct ForecastResult {
+    public let iob: [Double]
+    public let cob: [Double]
+    public let uam: [Double]
+    public let zt: [Double]
+}