Best Value: explain price age per surface instead of one blanket warning

- Station detail now separates the station's own report age from the selected fuel's update time, so a recent station-wide report no longer reads as an old price. - Warning copy names the fuel and says which side is weak: the station's price is not individually dated, or the baseline's is. The misleading "unverified or older than 7 days" line is gone. - Wording stays "Closest" throughout; new copy uses Unleaded / Premium / Diesel rather than the internal grade codes. - Localisation: new and updated keys for the added copy.
2026-10-15 21:37:35 +01:00
parent 7c2eeb2604
commit 9e77ee2947
8 changed files with 222 additions and 78 deletions
@@ -401,28 +401,27 @@ struct ContentView: View {
    /// (computing a journey for each) and `savingsLookup` immediately scanned them
    /// all AGAIN to fill the per-station map. Both now share one result.
    ///
-    /// The baseline is chosen with EXACTLY the loop and guards of
-    /// `FuelSavingsEstimator.baselineStation`, so the row labelled "Closest
-    /// station" cannot move — and it is still selected when the feature is
-    /// unconfigured (it names that row), while the maps are only built when the
-    /// labels will actually be shown.
+    /// The baseline is chosen with the same journey and selected-fuel freshness
+    /// guards as `FuelSavingsEstimator.bestValueBaselineStation` when configured;
+    /// with the feature off, the ordinary Closest station still names that row.
    private func savingsScaffold() -> (baseline: FuelStation?, journeys: [String: FuelSavingsJourney]) {
        guard let location else { return (nil, [:]) }
-        let configured = fuelSavingsSettings.isConfigured
+        guard fuelSavingsSettings.isConfigured else {
+            let baseline = FuelSavingsEstimator.baselineStation(stations, fuel: selectedFuel) {
+                savingsJourneyMiles(for: $0, location: location)
+            }
+            return (baseline, [:])
+        }
        var journeys: [String: FuelSavingsJourney] = [:]
-        var bestStation: FuelStation?
-        var bestMiles = Double.infinity
        for station in stations where station.prices[selectedFuel] != nil {
-            guard let journey = savingsJourneyMiles(for: station, location: location) else { continue }
-            if configured { journeys[station.id] = journey }
-            let miles = journey.miles
-            guard miles.isFinite, miles >= 0 else { continue }
-            if miles < bestMiles {
-                bestMiles = miles
-                bestStation = station
+            if let journey = savingsJourneyMiles(for: station, location: location) {
+                journeys[station.id] = journey
            }
        }
-        return (bestStation, configured ? journeys : [:])
+        let baseline = FuelSavingsEstimator.bestValueBaselineStation(stations, fuel: selectedFuel) {
+            journeys[$0.id]
+        }
+        return (baseline, journeys)
    }

    /// Row/detail savings lookup with the comparison baseline and the per-station
@@ -455,15 +454,15 @@ struct ContentView: View {
        }
    }

-    /// The nearest station that sells the selected fuel — the Best Value
-    /// comparison baseline. It is chosen with the SAME journey values used by
-    /// the savings calculation, so a cached road route can change the baseline
-    /// and keep the "extra return travel" labels synchronized with the
-    /// cost calculation. When no road route is cached, the journey falls back to
-    /// straight-line out-and-back, and the result is marked as an estimate.
+    /// The Closest station with an eligible selected-fuel price — the Best Value
+    /// comparison baseline. Ordinary Closest sorting still includes stale stations.
+    /// It uses the same journey values as the savings calculation, so a cached
+    /// road route can change the baseline and keep the "extra return travel"
+    /// labels synchronized with the cost calculation. Without a cached route,
+    /// the journey falls back to straight-line and the result is an estimate.
    private var nearestSavingsBaseline: FuelStation? {
        guard let location else { return nil }
-        return FuelSavingsEstimator.baselineStation(
+        return FuelSavingsEstimator.bestValueBaselineStation(
            stations,
            fuel: selectedFuel,
            journeyMiles: { [self] station in savingsJourneyMiles(for: station, location: location) }
@@ -803,6 +802,10 @@ struct ContentView: View {
                        fuelSavings: savingsLookup(baseline: scaffold.baseline,
                                                   journeys: scaffold.journeys)(station),
                        fuelSavingsAmount: sessionFuelSavingsAmount,
+                        savingsPriceConfidence: FuelPriceFreshness.ComparisonConfidence.assess(
+                            station: station, fuel: selectedFuel, baseline: scaffold.baseline),
+                        savingsPriceWarning: FuelPriceFreshness.comparisonWarning(
+                            station: station, fuel: selectedFuel, baseline: scaffold.baseline),
                        savingsBaselineStationName: scaffold.baseline?.name,
                        journeyDiagnostics: journeyDiagnostics(for: station, baseline: scaffold.baseline),
                        isFavourite: favouriteIDs.contains(station.id),
@@ -1119,6 +1122,11 @@ struct ContentView: View {
            }
        }
        .onChange(of: fuelSavingsSettings) { old, new in
+            // An explicit Settings default edit supersedes the temporary slider
+            // override. Changes to MPG/enabled alone leave the session fill intact.
+            if old.preferredAmount != new.preferredAmount {
+                sessionFuelSavingsAmount = new.preferredAmount
+            }
            // Fuel Savings changed in Settings while the app was running: the
            // effective sort follows automatically (no stored sort is touched).
 #if DEBUG
@@ -1524,6 +1532,12 @@ struct ContentView: View {
            fuelSavingsAmount: $sessionFuelSavingsAmount,
            savingsForStation: savingsLookup(baseline: baselineStation, journeys: scaffold.journeys),
            journeyDiagnosticsForStation: { station in journeyDiagnostics(for: station, baseline: baselineStation) },
+            savingsPriceConfidenceForStation: { station in
+                FuelPriceFreshness.ComparisonConfidence.assess(station: station, fuel: selectedFuel, baseline: baselineStation)
+            },
+            savingsPriceWarningForStation: { station in
+                FuelPriceFreshness.comparisonWarning(station: station, fuel: selectedFuel, baseline: baselineStation)
+            },
            onToggleFavourite: toggleFavourite,
            onRefresh: { await refresh(force: true) }
        )
@@ -1545,6 +1559,12 @@ struct ContentView: View {
            fuelSavingsAmount: $sessionFuelSavingsAmount,
            savingsForStation: savingsLookup(baseline: baselineStation, journeys: scaffold.journeys),
            journeyDiagnosticsForStation: { station in journeyDiagnostics(for: station, baseline: baselineStation) },
+            savingsPriceConfidenceForStation: { station in
+                FuelPriceFreshness.ComparisonConfidence.assess(station: station, fuel: selectedFuel, baseline: baselineStation)
+            },
+            savingsPriceWarningForStation: { station in
+                FuelPriceFreshness.comparisonWarning(station: station, fuel: selectedFuel, baseline: baselineStation)
+            },
            onToggleFavourite: toggleFavourite,
            onReorder: reorderFavourites,
            onHistoryUnavailable: { if dataStatus == .live { dataStatus = .connectionProblem } },
@@ -1782,6 +1802,8 @@ struct StationRow: View {
    /// compact banner does not print it today, but a row that carried a hard
    /// zero would print "for £0" the moment it did — pass the real figure.
    var fuelSavingsAmount: FuelSavingsFillAmount = FuelSavingsSettings.defaultPreferredAmount
+    var savingsPriceConfidence: FuelPriceFreshness.ComparisonConfidence = .ineligible
+    var savingsPriceWarning: String? = nil
    var onToggleFavourite: () -> Void = {}
    var onShowDetails: (FuelStation) -> Void = { _ in }

@@ -1942,6 +1964,8 @@ struct StationRow: View {
                FuelSavingsSummaryView(
                    availability: fuelSavings,
                    amount: fuelSavingsAmount,
+                    priceConfidence: savingsPriceConfidence,
+                    priceWarning: savingsPriceWarning,
                    compact: true,
                    distanceUnit: distanceUnit
                )