More info sheet: give the two station actions their own card below the map

Sharing the map's section made the buttons read as part of the map card and
the map tap target. They now sit in their own section, rendering as a
separate card directly beneath the map.

FuelBoard/ContentView.swift

@@ -566,34 +566,10 @@ struct ContentView: View {
         func source(_ basis: FuelSavingsDistanceBasis) -> String {
             basis == .roadRoute ? "road route" : "straight-line estimate"
         }
-        func amount(_ value: FuelSavingsFillAmount) -> String {
-            switch value.unit {
-            case .pounds: return String(format: "£%.2f", value.value)
-            case .litres: return String(format: "%.2f L", value.value)
-            }
-        }
-        func rawMoney(_ value: Double?) -> String {
-            value.map { String(format: "£%.6f", $0) } ?? "—"
-        }
-        let candidatePriceValue = station.prices[selectedFuel]
-        let baselinePriceValue = baseline?.prices[selectedFuel]
-        let price = candidatePriceValue.map { String(format: "%.1fp/L", $0) } ?? "—"
-        let baselinePrice = baselinePriceValue.map { String(format: "%.1fp/L", $0) } ?? "—"
-        let priceDifference = candidatePriceValue.flatMap { candidate in
-            baselinePriceValue.map { String(format: "%+.1fp/L", $0 - candidate) }
-        } ?? "—"
-        let litresBasis = sessionFuelSavingsAmount.unit == .pounds ? "candidate price" : "fixed litres"
+        let price = station.prices[selectedFuel].map { String(format: "%.1fp/L", $0) } ?? "—"
+        let baselinePrice = baseline?.prices[selectedFuel].map { String(format: "%.1fp/L", $0) } ?? "—"
         let rows: [(String, String)] = [
             ("Station", "\(station.name) (\(station.id))"),
-            ("Settings default fill-up", amount(fuelSavingsSettings.preferredAmount)),
-            ("Effective/session fill-up", amount(sessionFuelSavingsAmount)),
-            ("Fill-up unit", sessionFuelSavingsAmount.unit.displayName),
-            ("MPG", String(format: "%.1f UK MPG", fuelSavingsSettings.mpg)),
-            ("Candidate price", price),
-            ("Baseline price", baselinePrice),
-            ("Price difference", priceDifference),
-            ("Candidate litres", result.map { String(format: "%.6f L · %@", $0.fillLitres, litresBasis) } ?? "—"),
-            ("Gross saving raw", rawMoney(result?.grossSavingGBP)),
             ("Displayed distance", "\(distanceUnit.format(stationDistance.displayDistanceKM)) · \(source(stationDistance.displaySource))"),
             ("Outward road", meters(stationDistance.outwardMeters)),
             ("Return road", stationDistance.hasMeasuredReturn ? meters(stationDistance.returnMeters) : "inferred or unavailable"),
@@ -605,11 +581,12 @@ struct ContentView: View {
             ("Station journey", miles(journey?.miles)),
             ("Baseline journey", miles(baselineJourney?.miles)),
             ("Additional journey", miles(result?.extraDistanceMiles)),
-            ("Additional fuel used", result.map { String(format: "%.6f L", $0.extraFuelLitres) } ?? "—"),
             ("Confidence", result?.journeyConfidence.rawValue ?? "estimated"),
-            ("Travel cost raw", rawMoney(result?.extraDrivingCostGBP)),
-            ("Net saving raw", rawMoney(result?.netSavingGBP)),
-            ("Displayed net saving", result?.headline() ?? "—")
+            ("Fuel price", price),
+            ("Baseline price", baselinePrice),
+            ("Gross saving", result.map { FuelSavingsFormat.money($0.grossSavingGBP) } ?? "—"),
+            ("Travel cost", result.map { FuelSavingsFormat.money($0.extraDrivingCostGBP) } ?? "—"),
+            ("Net saving", result.map { FuelSavingsFormat.money($0.netSavingGBP) } ?? "—")
         ]
         return FuelSavingsJourneyDiagnostics(rows: rows)
         #else
@@ -1127,13 +1104,6 @@ struct ContentView: View {
             ensureBestValueAlertModeIsAvailable()
             updateAlertMonitor()
         }
-        .onChange(of: sessionFuelSavingsAmount) { _, _ in
-            // This remains a session-only override: do not write it to FuelStore.
-            // Any active Best Value alert/Live Activity must nevertheless use
-            // the same effective amount as rows, details, favourites and sorting.
-            updateAlertMonitor()
-            updateLiveActivity()
-        }
         .onChange(of: scenePhase) { _, newPhase in
             if newPhase == .active {
                 // Never start location tracking while onboarding is on screen —

FuelBoard/FuelSavingsViews.swift

@@ -119,9 +119,6 @@ struct FuelSavingsSummaryView: View {
                 VStack(alignment: .leading, spacing: 10) {
                     capsule(for: result, compact: false)
                         .accessibilityLabel(accessibilityHeadline(for: result))
-                    LabeledContent("Your fill-up", value: amountText)
-                    LabeledContent("Fuel you'll receive", value: String(format: "%.2f litres", result.fillLitres))
-                        .monospacedDigit()
                     if let extraTravel = FuelSavingsFormat.extraTravelLabel(
                         extraDistanceMiles: result.extraDistanceMiles,
                         unit: distanceUnit,
@@ -137,26 +134,9 @@ struct FuelSavingsSummaryView: View {
                             .font(.caption)
                             .foregroundStyle(.secondary)
                     } else {
-                        Text("Compared with \(baselineStationName ?? "your nearest station").")
-                            .font(.caption)
-                            .foregroundStyle(.secondary)
-                        LabeledContent(
-                            result.grossSavingGBP >= 0 ? "Fuel-price saving" : "Fuel-price difference",
-                            value: result.grossSavingGBP >= 0
-                                ? FuelSavingsFormat.money(result.grossSavingGBP)
-                                : "Costs \(FuelSavingsFormat.money(abs(result.grossSavingGBP))) more"
-                        )
+                        Text("Compared with \(baselineStationName ?? "your nearest station") for \(amountText).").font(.caption).foregroundStyle(.secondary)
+                        LabeledContent("Fuel-price saving", value: FuelSavingsFormat.money(result.grossSavingGBP))
                         LabeledContent("Extra driving cost", value: FuelSavingsFormat.money(result.extraDrivingCostGBP))
-                        Divider()
-                        LabeledContent {
-                            Text(result.headline())
-                                .fontWeight(.semibold)
-                                .foregroundStyle(capsuleColor(for: result.status))
-                                .monospacedDigit()
-                        } label: {
-                            Text("Total")
-                                .fontWeight(.semibold)
-                        }
                         if result.journeyConfidence.isEstimated {
                             Text("Estimated from straight-line or incomplete route data — refined once both routes are measured.")
                                 .font(.caption2)

FuelBoard/ProximityMonitor.swift

@@ -618,7 +618,7 @@ final class ProximityMonitor: NSObject, ObservableObject, @preconcurrency CLLoca
         let content = UNMutableNotificationContent()
         content.sound = .default
         content.title = "Best Value \(fuel.displayName) nearby: \(brand)"
-        content.body = "\(station.name): \(result.headline()). Tap for directions."
+        content.body = "\(station.name) could leave you \(result.headline()). Tap for directions."
         addAlertRequest(content: content, station: station)
         logAlert(.fired, "Best Value alert scheduled — \(brand) · \(result.headline())")
         lastAlert = "Best Value · \(brand) · \(result.headline())"
@@ -923,7 +923,7 @@ final class ProximityMonitor: NSObject, ObservableObject, @preconcurrency CLLoca
         content.sound = .default
         let brand = candidate.station.brand.isEmpty ? candidate.station.name : candidate.station.brand
         content.title = "Best Value \(fuel.displayName) nearby: \(brand)"
-        content.body = "\(candidate.station.name): \(candidate.result.headline()). Tap for directions."
+        content.body = "\(candidate.station.name) could leave you \(candidate.result.headline()). Tap for directions."
         let baseResult = "Best Value · \(brand) · \(candidate.result.headline()) · radius \(unit.format(radiusKM))"
         lastTestResult = baseResult
         logAlert(.fired, "Best Value test alert scheduled — \(brand) · \(candidate.result.headline())")

FuelBoard/StationDetailView.swift

@@ -29,6 +29,10 @@ struct StationDetailView: View {
     var onToggleFavourite: (() -> Void)? = nil
     @Environment(\.dismiss) private var dismiss
     @State private var showingReportIssueConfirmation = false
+    /// Transient "Copied" confirmation on the Address row. Cleared by a task so
+    /// the caption fades out on its own.
+    @State private var showingCopied = false
+    @State private var copyResetTask: Task<Void, Never>?
 
     private let reportIssueURL = URL(string: "https://www.gov.uk/guidance/report-an-error-in-fuel-prices-or-forecourt-details")!
 
@@ -36,10 +40,61 @@ struct StationDetailView: View {
         CLLocationCoordinate2D(latitude: station.lat, longitude: station.lng)
     }
 
+    /// The row's address text — the same shared line the listing row uses, with
+    /// any leading repeat of the station name stripped.
+    private var addressLine: String {
+        StationAddressLine.display(address: station.address,
+                                   postcode: station.postcode,
+                                   name: station.name)
+    }
+
+    /// The station's postcode, trimmed. Empty means there is nothing to copy and
+    /// the Address row stays inert.
+    private var postcodeForCopying: String {
+        station.postcode.trimmingCharacters(in: .whitespacesAndNewlines)
+    }
+
+    /// Opens Apple Maps driving directions — the same destination (and the same
+    /// URL) the Directions button below uses, so the map and the button can
+    /// never point at two different places.
+    private func openDirections() {
+        if let url = station.mapsDirectionsURL {
+            UIApplication.shared.open(url)
+        }
+    }
+
+    /// Copies ONLY the postcode, so it can be pasted into another navigation app
+    /// without dragging the station name and street along with it. Confirms with
+    /// a light haptic and a caption that fades after ~2s.
+    private func copyPostcode() {
+        let postcode = postcodeForCopying
+        guard !postcode.isEmpty else { return }
+        UIPasteboard.general.string = postcode
+        UINotificationFeedbackGenerator().notificationOccurred(.success)
+        withAnimation(.easeInOut(duration: 0.2)) { showingCopied = true }
+        copyResetTask?.cancel()
+        copyResetTask = Task {
+            try? await Task.sleep(nanoseconds: 2_000_000_000)
+            guard !Task.isCancelled else { return }
+            withAnimation(.easeInOut(duration: 0.3)) { showingCopied = false }
+        }
+    }
+
     var body: some View {
         NavigationStack {
             List {
                 Section {
+                    // Tapping anywhere on the map opens the same Apple Maps
+                    // directions the Directions button below opens.
+                    //
+                    // The tap target is an OVERLAY Button laid ON TOP of the
+                    // Map, not a Button wrapping it. A Map runs its own UIKit
+                    // view, and inside a List row the wrapped-Map form left the
+                    // card untappable — the touch never reached the button. An
+                    // overlay sits above the map, owns an explicit rounded-rect
+                    // content shape, and cannot be intercepted by MapKit. The
+                    // Map itself stays non-interactive: it is a preview, not
+                    // something to pan.
                     Map(position: .constant(.region(MKCoordinateRegion(
                         center: stationCoordinate,
                         span: MKCoordinateSpan(latitudeDelta: 0.02, longitudeDelta: 0.02)
@@ -50,16 +105,83 @@ struct StationDetailView: View {
                     .frame(height: 180)
                     .clipShape(RoundedRectangle(cornerRadius: 12))
                     .allowsHitTesting(false)
+                    .overlay {
+                        Button {
+                            openDirections()
+                        } label: {
+                            Color.clear
+                                .contentShape(RoundedRectangle(cornerRadius: 12))
+                        }
+                        .buttonStyle(.plain)
+                        .accessibilityLabel(String(localized: "Directions to \(station.name)",
+                                                   comment: "Accessibility label for the tappable map preview in the More info sheet"))
+                        .accessibilityHint(String(localized: "Opens Apple Maps with driving directions",
+                                                  comment: "Accessibility hint for the tappable map preview in the More info sheet"))
+                    }
                     .listRowInsets(EdgeInsets())
                 }
+                // The two station actions live in their OWN section, so they
+                // render as a separate card BELOW the map instead of sharing the
+                // map's card and looking attached to the map tap target.
+                Section {
+                    HStack(spacing: 12) {
+                        Button {
+                            openDirections()
+                        } label: {
+                            Label("Directions", systemImage: "arrow.triangle.turn.up.right.diamond.fill")
+                                .frame(maxWidth: .infinity)
+                        }
+                        Button(role: .destructive) {
+                            showingReportIssueConfirmation = true
+                        } label: {
+                            Label("Report issue", systemImage: "exclamationmark.bubble.fill")
+                                .frame(maxWidth: .infinity)
+                        }
+                    }
+                }
                 Section {
                     // The station name is NOT repeated here: the sheet header
                     // (navigationTitle, inline) already shows it, and the address
                     // line below has any leading repeat of the name stripped, so
                     // a "Name" row only said it twice.
-                    LabeledContent("Address", value: StationAddressLine.display(address: station.address,
-                                                                             postcode: station.postcode,
-                                                                             name: station.name))
+                    //
+                    // The whole row is a copy control: it puts JUST the postcode
+                    // on the clipboard so it can be pasted into another
+                    // navigation app. The copy glyph and its "Copied"
+                    // confirmation share a SECOND line that is always there, so
+                    // the confirmation can never reflow the address above it.
+                    Button {
+                        copyPostcode()
+                    } label: {
+                        VStack(alignment: .leading, spacing: 6) {
+                            HStack(alignment: .firstTextBaseline, spacing: 8) {
+                                Text("Address")
+                                Spacer(minLength: 8)
+                                Text(addressLine)
+                                    .multilineTextAlignment(.trailing)
+                                    .foregroundStyle(.secondary)
+                            }
+                            HStack(spacing: 4) {
+                                Spacer(minLength: 0)
+                                if showingCopied {
+                                    Text("Copied")
+                                        .foregroundStyle(.green)
+                                        .transition(.opacity)
+                                }
+                                Image(systemName: showingCopied ? "checkmark" : "doc.on.doc")
+                                    .foregroundStyle(showingCopied ? Color.green : Color.secondary)
+                            }
+                            .font(.footnote.weight(.semibold))
+                        }
+                    }
+                    .buttonStyle(.plain)
+                    .disabled(postcodeForCopying.isEmpty)
+                    .accessibilityLabel(String(localized: "Address: \(addressLine)",
+                                               comment: "Accessibility label for the address row in the More info sheet"))
+                    .accessibilityHint(postcodeForCopying.isEmpty
+                        ? ""
+                        : String(localized: "Copies the postcode",
+                                 comment: "Accessibility hint for the address row in the More info sheet"))
                     if let location {
                         let distance = FuelStore.stationDistanceDisplay(
                             station: station, userLat: location.lat, userLng: location.lng
@@ -105,20 +227,6 @@ struct StationDetailView: View {
                 }
 #endif
 
-                Section {
-                    Button {
-                        if let url = station.mapsDirectionsURL {
-                            UIApplication.shared.open(url)
-                        }
-                    } label: {
-                        Label("Directions", systemImage: "arrow.triangle.turn.up.right.diamond.fill")
-                    }
-                    Button(role: .destructive) {
-                        showingReportIssueConfirmation = true
-                    } label: {
-                        Label("Report issue", systemImage: "exclamationmark.bubble.fill")
-                    }
-                }
             }
             .navigationTitle(station.name)
             .navigationBarTitleDisplayMode(.inline)
@@ -149,6 +257,18 @@ struct StationDetailView: View {
                     )
                 }
             }
+            // The "Copied" fade-out task must not outlive the sheet.
+            .onDisappear { copyResetTask?.cancel() }
+#if DEBUG
+            // QA hook: `-qaCopyPostcode` runs the REAL copy on open, so the
+            // clipboard value (read back with `xcrun simctl pbpaste`) and the
+            // "Copied" confirmation can be verified without a tap — simctl
+            // cannot drive taps into the Simulator.
+            .task {
+                guard ProcessInfo.processInfo.arguments.contains("-qaCopyPostcode") else { return }
+                copyPostcode()
+            }
+#endif
         }
     }
 }

FuelBoard/StationsView.swift

@@ -249,7 +249,7 @@ struct StationsView: View {
                             VStack(spacing: 10) {
                                 keyCard(
                                     icon: "checkmark.circle.fill", color: .green,
-                                    title: "Good price", blurb: "Within 1.5p of the cheapest",
+                                    title: "Best value", blurb: "Within 1.5p of the cheapest",
                                     threshold: "≤1.5p")
                                 keyCard(
                                     icon: "equal.circle.fill", color: .orange,
@@ -298,17 +298,6 @@ struct StationsView: View {
                             .listRowBackground(Color.clear)
                             .listRowInsets(EdgeInsets(top: 4, leading: 16, bottom: 4, trailing: 16))
                         }
-
-                        Section("How Best Value works") {
-                            VStack(alignment: .leading, spacing: 10) {
-                                Text("Best Value compares each station with the closest one. It works out what you could save at the pump, then takes off the fuel used for the extra return journey.")
-                                Text("Your fill-up amount and MPG are used to show whether you could save overall.")
-                                Text("Results are marked “Approx.” until road distances are available.")
-                                    .foregroundStyle(.secondary)
-                            }
-                            .font(.subheadline)
-                            .padding(.vertical, 4)
-                        }
                     }
                     .navigationTitle("Key")
                     .navigationBarTitleDisplayMode(.inline)

FuelBoard/en.lproj/Localizable.strings

@@ -23,7 +23,7 @@
 "Show %lld more (%lld remaining)" = "Show %lld more (%lld remaining)";
 "All %lld stations shown" = "All %lld stations shown";
 "Key" = "Key";
-"Good price" = "Good price";
+"Best value" = "Best value";
 "Within 1.5p of the cheapest" = "Within 1.5p of the cheapest";
 "Okay" = "Okay";
 "Within 4p of the cheapest" = "Within 4p of the cheapest";
@@ -35,10 +35,6 @@
 "Add to favourites" = "Add to favourites";
 "Remove from favourites" = "Remove from favourites";
 "Colours match each station's rating on the list" = "Colours match each station's rating on the list";
-"How Best Value works" = "How Best Value works";
-"Best Value compares each station with the closest one. It works out what you could save at the pump, then takes off the fuel used for the extra return journey." = "Best Value compares each station with the closest one. It works out what you could save at the pump, then takes off the fuel used for the extra return journey.";
-"Your fill-up amount and MPG are used to show whether you could save overall." = "Your fill-up amount and MPG are used to show whether you could save overall.";
-"Results are marked “Approx.” until road distances are available." = "Results are marked “Approx.” until road distances are available.";
 
 /* Favourites tab */
 "No favourites yet" = "No favourites yet";
@@ -71,6 +67,11 @@
 "Name" = "Name";
 "Address" = "Address";
 "Distance" = "Distance";
+"Copied" = "Copied";
+"Copies the postcode" = "Copies the postcode";
+"Address: %@" = "Address: %@";
+"Directions to %@" = "Directions to %@";
+"Opens Apple Maps with driving directions" = "Opens Apple Maps with driving directions";
 "Show introduction" = "Replay onboarding";
 "Replay the welcome screen, including the location and notification permission prompts." = "Replay the welcome screen, including the location and notification permission prompts.";
 "Test alert notification (real data)" = "Test alert notification (real data)";
@@ -198,7 +199,6 @@
 "Cheapest station" = "Cheapest station";
 "Alert type" = "Alert type";
 "Best Value" = "Best Value";
-"Total" = "Total";
 "Minimum saving" = "Minimum saving";
 "Set up Best Value first so FuelBoard can account for your fill size, MPG and travel cost." = "Set up Best Value first so FuelBoard can account for your fill size, MPG and travel cost.";
 "Set up Best Value first so Best Value alerts can account for your fill size, MPG and travel cost." = "Set up Best Value first so Best Value alerts can account for your fill size, MPG and travel cost.";

FuelBoardTests/Tests/FuelBoardSharedTests/FuelSavingsCalculationAuditTests.swift

@@ -82,84 +82,18 @@ final class FuelSavingsCalculationAuditTests: XCTestCase {
         XCTAssertEqual(FuelSavingsFormat.distance(1, unit: .miles), DistanceUnit.miles.format(1.609344))
     }
 
-    // MARK: - 2. Candidate-priced fill-up
-
-    func testPoundsFillUsesCandidatePriceForLitresAndGrossSaving() throws {
-        let result = try FuelSavingsCalculator.calculate(
-            mpg: 30,
-            amount: FuelSavingsFillAmount(value: 60, unit: .pounds),
-            baselinePricePencePerLitre: 171.9,
-            candidatePricePencePerLitre: 169.9,
-            baselineJourneyMiles: 0.879,
-            candidateJourneyMiles: 8.306
-        )
-
-        XCTAssertEqual(result.fillLitres, 60 / 1.699, accuracy: 1e-9)
-        XCTAssertEqual(result.grossSavingGBP, (60 / 1.699) * 0.02, accuracy: 1e-9)
-        XCTAssertEqual(FuelSavingsFormat.money(result.grossSavingGBP), "£0.71")
-        XCTAssertEqual(result.extraFuelLitres, 1.1254603476666667, accuracy: 1e-9)
-        XCTAssertEqual(result.extraDrivingCostGBP, 1.9121571306856667, accuracy: 1e-9)
-        XCTAssertEqual(result.netSavingGBP, -1.2058593084372853, accuracy: 1e-9)
-        XCTAssertEqual(result.headline(), "Costs £1.21 more")
-    }
-
-    func testPoundsExamplesScaleFromThirtyToOneHundredPounds() throws {
-        for (budget, expectedLitres, expectedGross) in [
-            (30.0, 17.657445556209535, 0.3531489111241907),
-            (60.0, 35.31489111241907, 0.7062978222483814),
-            (100.0, 58.85815185403179, 1.1771630370806357)
-        ] {
-            let result = try FuelSavingsCalculator.calculate(
-                mpg: 30,
-                amount: FuelSavingsFillAmount(value: budget, unit: .pounds),
-                baselinePricePencePerLitre: 171.9,
-                candidatePricePencePerLitre: 169.9,
-                baselineJourneyMiles: 0,
-                candidateJourneyMiles: 0
-            )
-            XCTAssertEqual(result.fillLitres, expectedLitres, accuracy: 1e-8)
-            XCTAssertEqual(result.grossSavingGBP, expectedGross, accuracy: 1e-8)
-        }
-    }
-
-    func testCandidatePriceControlsLitresWhileBaselinePriceOnlyChangesSaving() throws {
-        let amount = FuelSavingsFillAmount(value: 60, unit: .pounds)
-        let first = try FuelSavingsCalculator.calculate(
-            mpg: 30, amount: amount,
-            baselinePricePencePerLitre: 171.9,
-            candidatePricePencePerLitre: 169.9,
-            baselineJourneyMiles: 0, candidateJourneyMiles: 0
-        )
-        let differentBaseline = try FuelSavingsCalculator.calculate(
-            mpg: 30, amount: amount,
-            baselinePricePencePerLitre: 179.9,
-            candidatePricePencePerLitre: 169.9,
-            baselineJourneyMiles: 0, candidateJourneyMiles: 0
-        )
-        let differentCandidate = try FuelSavingsCalculator.calculate(
-            mpg: 30, amount: amount,
-            baselinePricePencePerLitre: 179.9,
-            candidatePricePencePerLitre: 159.9,
-            baselineJourneyMiles: 0, candidateJourneyMiles: 0
-        )
-
-        XCTAssertEqual(first.fillLitres, differentBaseline.fillLitres, accuracy: 1e-12)
-        XCTAssertNotEqual(first.grossSavingGBP, differentBaseline.grossSavingGBP)
-        XCTAssertNotEqual(differentBaseline.fillLitres, differentCandidate.fillLitres)
-    }
-
-    // MARK: - 3/5. The three stations from the brief
+    // MARK: - 2/4. The three stations from the brief
 
     func testBriefCaseTescoBradfordIsMarginallyWorseOff() throws {
         let result = try briefResult(candidatePrice: 170.9, extraMiles: 2.0)
 
-        XCTAssertEqual(result.fillLitres, 35.108250, accuracy: 1e-6)
-        XCTAssertEqual(result.grossSavingGBP, 0.351083, accuracy: 1e-6, "£60 buys 35.11 L at the candidate price")
+        XCTAssertEqual(result.fillLitres, 34.904014, accuracy: 1e-6)
+        XCTAssertEqual(result.grossSavingGBP, 0.349040, accuracy: 1e-6, "1p/litre cheaper on a 34.90 L fill")
         XCTAssertEqual(result.extraDistanceMiles, 2.0, accuracy: 1e-9)
         XCTAssertEqual(result.extraDrivingCostGBP, 0.517951, accuracy: 1e-6)
-        XCTAssertEqual(result.netSavingGBP, -0.166869, accuracy: 1e-6)
+        XCTAssertEqual(result.netSavingGBP, -0.168911, accuracy: 1e-6)
         XCTAssertEqual(result.status, .notWorthTheDrive)
-        XCTAssertEqual(result.headline(), "Costs £0.17 more")
+        XCTAssertEqual(result.headline(), "£0.17 worse off after travel")
     }
 
     /// The brief recorded "£0.18 worse off" for this row against a displayed
@@ -170,9 +104,9 @@ final class FuelSavingsCalculationAuditTests: XCTestCase {
     /// is entirely the rounding of the distance, not of the money.
     func testTheReportedEighteenPenceIsRoundedExtraDistanceNotARoundingBug() throws {
         XCTAssertEqual(try briefResult(candidatePrice: 170.9, extraMiles: 2.00).headline(),
-                       "Costs £0.17 more")
+                       "£0.17 worse off after travel")
         XCTAssertEqual(try briefResult(candidatePrice: 170.9, extraMiles: 2.05).headline(),
-                       "Costs £0.18 more")
+                       "£0.18 worse off after travel")
 
         // 2.05 mi shows as "2.0 mi" at one decimal place — the same caption.
         XCTAssertEqual(FuelSavingsFormat.extraTravelLabel(extraDistanceMiles: 2.05, unit: .miles),
@@ -184,13 +118,13 @@ final class FuelSavingsCalculationAuditTests: XCTestCase {
     func testBriefCaseMFGHareAndHoundsIsWorseOff() throws {
         let result = try briefResult(candidatePrice: 172.9, extraMiles: 2.8)
 
-        XCTAssertEqual(result.fillLitres, 34.702140, accuracy: 1e-6)
-        XCTAssertEqual(result.grossSavingGBP, -0.347021, accuracy: 1e-6, "£60 buys 34.70 L at the candidate price")
+        XCTAssertEqual(result.fillLitres, 34.904014, accuracy: 1e-6)
+        XCTAssertEqual(result.grossSavingGBP, -0.349040, accuracy: 1e-6, "1p/litre dearer costs 34.90 L × 1p")
         XCTAssertEqual(result.extraDistanceMiles, 2.8, accuracy: 1e-9)
         XCTAssertEqual(result.extraDrivingCostGBP, 0.733618, accuracy: 1e-6)
-        XCTAssertEqual(result.netSavingGBP, -1.080639, accuracy: 1e-6)
+        XCTAssertEqual(result.netSavingGBP, -1.082658, accuracy: 1e-6)
         XCTAssertEqual(result.status, .notWorthTheDrive)
-        XCTAssertEqual(result.headline(), "Costs £1.08 more")
+        XCTAssertEqual(result.headline(), "£1.08 worse off after travel")
     }
 
     func testBriefCasePGGNapoleonSamePumpPriceIsTravelCostOnly() throws {
@@ -201,7 +135,7 @@ final class FuelSavingsCalculationAuditTests: XCTestCase {
         XCTAssertEqual(result.netSavingGBP, -0.729375, accuracy: 1e-6,
                        "with no price difference the whole result is the extra driving")
         XCTAssertEqual(result.status, .notWorthTheDrive)
-        XCTAssertEqual(result.headline(), "Costs £0.73 more")
+        XCTAssertEqual(result.headline(), "£0.73 worse off after travel")
     }
 
     // MARK: - 5/6. Classification, tolerance and rounding
@@ -216,15 +150,15 @@ final class FuelSavingsCalculationAuditTests: XCTestCase {
     }
 
     func testSmallSavingInsideTheToleranceIsBreakEvenNotPennies() throws {
-        // 171.9p vs 170.9p over a 1.23 mi delta: the small saving remains within tolerance.
+        // 171.9p vs 170.9p over a 1.23 mi delta: net +£0.0305.
         let result = try briefResult(candidatePrice: 170.9, extraMiles: 1.23)
-        XCTAssertEqual(result.netSavingGBP, 0.03254252417853143, accuracy: 1e-9)
+        XCTAssertEqual(result.netSavingGBP, 0.030500, accuracy: 1e-6)
         XCTAssertEqual(result.status, .breakEven, "±5p reads as break even rather than a meaningless £0.03")
         XCTAssertEqual(result.headline(), "Break even")
     }
 
     func testBreakEvenToleranceDecidesTheClassificationAtTheBoundary() throws {
-        let net = -0.166869
+        let net = -0.168911
         // A tolerance wider than the loss → break even; narrower → worse off.
         let lenient = try FuelSavingsCalculator.calculate(
             mpg: 30,
@@ -253,7 +187,7 @@ final class FuelSavingsCalculationAuditTests: XCTestCase {
     func testMoneyIsRoundedOnlyForDisplay() throws {
         // Full precision retained internally…
         let result = try briefResult(candidatePrice: 172.9, extraMiles: 2.8)
-        XCTAssertEqual(result.netSavingGBP, -1.080639, accuracy: 1e-6)
+        XCTAssertEqual(result.netSavingGBP, -1.082658, accuracy: 1e-6)
         XCTAssertNotEqual(result.netSavingGBP, -1.08, "the stored value must not be pre-rounded")
         // …and rounded to two places only when shown.
         XCTAssertEqual(FuelSavingsFormat.money(1.082658), "£1.08")
@@ -303,12 +237,12 @@ final class FuelSavingsCalculationAuditTests: XCTestCase {
             baselineJourneyMiles: 2.0,
             candidateJourneyMiles: 7.0
         )
-        XCTAssertEqual(result.fillLitres, 28.797696, accuracy: 1e-6)
-        XCTAssertEqual(result.grossSavingGBP, 2.015839, accuracy: 1e-6)
+        XCTAssertEqual(result.fillLitres, 27.416038, accuracy: 1e-6)
+        XCTAssertEqual(result.grossSavingGBP, 1.919123, accuracy: 1e-6)
         XCTAssertEqual(result.extraDrivingCostGBP, 0.701613, accuracy: 1e-6)
-        XCTAssertEqual(result.netSavingGBP, 1.314226, accuracy: 1e-6)
+        XCTAssertEqual(result.netSavingGBP, 1.217509, accuracy: 1e-6)
         XCTAssertEqual(result.status, .worthTheDrive)
-        XCTAssertEqual(result.headline(), "Save £1.31")
+        XCTAssertEqual(result.headline(), "£1.22 better off after travel")
     }
 
     func testNearerCandidateIsNeverChargedExtraTravel() throws {
@@ -336,9 +270,9 @@ final class FuelSavingsCalculationAuditTests: XCTestCase {
             baselineJourneyMiles: 0.8,
             candidateJourneyMiles: 3.6
         )
-        XCTAssertEqual(sixty.grossSavingGBP, -0.347021, accuracy: 1e-6, "MPG must not touch the pump saving")
+        XCTAssertEqual(sixty.grossSavingGBP, -0.349040, accuracy: 1e-6, "MPG must not touch the pump saving")
         XCTAssertEqual(sixty.extraDrivingCostGBP, 0.366809, accuracy: 1e-6)
-        XCTAssertEqual(sixty.netSavingGBP, -0.713830, accuracy: 1e-6)
+        XCTAssertEqual(sixty.netSavingGBP, -0.715849, accuracy: 1e-6)
 
         let fortyFive = try FuelSavingsCalculator.calculate(
             mpg: 45,
@@ -349,7 +283,7 @@ final class FuelSavingsCalculationAuditTests: XCTestCase {
             candidateJourneyMiles: 3.6
         )
         XCTAssertEqual(fortyFive.extraDrivingCostGBP, 0.489078, accuracy: 1e-6)
-        XCTAssertEqual(fortyFive.netSavingGBP, -0.836100, accuracy: 1e-6)
+        XCTAssertEqual(fortyFive.netSavingGBP, -0.838119, accuracy: 1e-6)
     }
 
     func testDifferentFillBudgetsScaleOnlyThePumpSaving() throws {
@@ -361,10 +295,10 @@ final class FuelSavingsCalculationAuditTests: XCTestCase {
             baselineJourneyMiles: 0.8,
             candidateJourneyMiles: 3.6
         )
-        XCTAssertEqual(forty.fillLitres, 23.134760, accuracy: 1e-6, "£40 buys 23.13 L at the candidate price")
-        XCTAssertEqual(forty.grossSavingGBP, -0.231348, accuracy: 1e-6)
+        XCTAssertEqual(forty.fillLitres, 23.269343, accuracy: 1e-6, "£40 buys 23.27 L at 171.9p")
+        XCTAssertEqual(forty.grossSavingGBP, -0.232693, accuracy: 1e-6)
         XCTAssertEqual(forty.extraDrivingCostGBP, 0.733618, accuracy: 1e-6, "the journey cost is budget-independent")
-        XCTAssertEqual(forty.netSavingGBP, -0.964965, accuracy: 1e-6)
+        XCTAssertEqual(forty.netSavingGBP, -0.966311, accuracy: 1e-6)
 
         let ninety = try FuelSavingsCalculator.calculate(
             mpg: 30,
@@ -374,9 +308,9 @@ final class FuelSavingsCalculationAuditTests: XCTestCase {
             baselineJourneyMiles: 0.8,
             candidateJourneyMiles: 3.6
         )
-        XCTAssertEqual(ninety.fillLitres, 52.053210, accuracy: 1e-6)
-        XCTAssertEqual(ninety.grossSavingGBP, -0.520532, accuracy: 1e-6)
-        XCTAssertEqual(ninety.netSavingGBP, -1.254150, accuracy: 1e-6)
+        XCTAssertEqual(ninety.fillLitres, 52.356021, accuracy: 1e-6)
+        XCTAssertEqual(ninety.grossSavingGBP, -0.523560, accuracy: 1e-6)
+        XCTAssertEqual(ninety.netSavingGBP, -1.257178, accuracy: 1e-6)
     }
 
     func testFillUpInLitresIsFixedRegardlessOfPrice() throws {
@@ -436,7 +370,7 @@ final class FuelSavingsCalculationAuditTests: XCTestCase {
             journey: journey(2.8),
             baselineJourney: journey(0.8)
         )
-        XCTAssertEqual(both?.result?.netSavingGBP ?? 0, -0.166869, accuracy: 1e-6)
+        XCTAssertEqual(both?.result?.netSavingGBP ?? 0, -0.168911, accuracy: 1e-6)
     }
 
     func testMixedRouteBasisIsReportedAsAnEstimate() {
@@ -459,7 +393,7 @@ final class FuelSavingsCalculationAuditTests: XCTestCase {
         XCTAssertEqual(mixed?.result?.distanceBasis, .straightLine,
                        "one unmeasured leg makes the whole estimate an estimate")
         XCTAssertEqual(mixed?.result?.journeyConfidence, .estimated)
-        XCTAssertEqual(mixed?.result?.headline(compact: true), "Approx. Costs £0.17 more")
+        XCTAssertEqual(mixed?.result?.headline(compact: true), "Approx. £0.17 worse off after travel")
     }
 
     func testBaselineStationIsLabelledClosestStationNotBreakEven() {

FuelBoardTests/Tests/FuelBoardSharedTests/FuelSavingsEstimateTests.swift

@@ -284,9 +284,9 @@ final class FuelSavingsEstimateTests: XCTestCase {
     /// (171.9p, 0.4 mi), candidate Shell Whetley Hill (167.9p, 3.8 mi).
     ///
     /// Whetley Hill is 4p/litre cheaper, yet it is WORSE OFF — and that is
-    /// correct, not a calculation bug: £60 buys 35.74 L at 167.9p, so the
-    /// cheaper pump saves 35.74 × 4p = £1.43, while the extra 6.8 return miles
-    /// burn 6.8/30 × 4.54609 = 1.03 L at 167.9p = £1.73. Net ≈ −£0.30.
+    /// correct, not a calculation bug: £60 buys 34.90 L at 171.9p, so the
+    /// cheaper pump saves 34.90 × 4p = £1.40, while the extra 6.8 return miles
+    /// burn 6.8/30 × 4.54609 = 1.03 L at 167.9p = £1.73. Net ≈ −£0.33.
     func testCheaperStationFurtherAwayIsWorseOffAfterTravel() {
         let baseline = station("rontec-shelf", price: 171.9)
         let candidate = station("shell-whetley-hill", price: 167.9)
@@ -304,16 +304,16 @@ final class FuelSavingsEstimateTests: XCTestCase {
         guard let result = availability?.result else {
             return XCTFail("expected an estimate, got \(String(describing: availability))")
         }
-        XCTAssertEqual(result.fillLitres, 35.736, accuracy: 0.005,
-                       "the £60 budget buys litres at the candidate pump price")
-        XCTAssertEqual(result.grossSavingGBP, 1.429, accuracy: 0.005)
+        XCTAssertEqual(result.fillLitres, 34.904, accuracy: 0.005,
+                       "the £60 budget buys litres at the BASELINE pump price")
+        XCTAssertEqual(result.grossSavingGBP, 1.396, accuracy: 0.005)
         XCTAssertEqual(result.extraDistanceMiles, 6.8, accuracy: 0.001,
                        "only the return-trip DELTA counts — the shared journey is never counted twice")
         XCTAssertEqual(result.extraDrivingCostGBP, 1.730, accuracy: 0.005)
-        XCTAssertEqual(result.netSavingGBP, -0.301, accuracy: 0.005)
+        XCTAssertEqual(result.netSavingGBP, -0.334, accuracy: 0.005)
         XCTAssertEqual(result.status, .notWorthTheDrive)
         XCTAssertEqual(result.journeyConfidence, .estimated)
-        XCTAssertEqual(result.headline(compact: true), "Approx. Costs £0.30 more")
+        XCTAssertEqual(result.headline(compact: true), "Approx. £0.33 worse off after travel")
     }
 
     func testMeasuredRoadRoutesDropTheEstimateMarker() {
@@ -332,8 +332,8 @@ final class FuelSavingsEstimateTests: XCTestCase {
 
         XCTAssertEqual(availability?.result?.distanceBasis, .roadRoute)
         XCTAssertEqual(availability?.result?.journeyConfidence, .confirmed)
-        XCTAssertEqual(availability?.result?.headline(compact: true), "Costs £0.30 more")
-        XCTAssertEqual(availability?.result?.headline(), "Costs £0.30 more")
+        XCTAssertEqual(availability?.result?.headline(compact: true), "£0.33 worse off after travel")
+        XCTAssertEqual(availability?.result?.headline(), "£0.33 worse off after travel")
     }
 
     func testBaselineRowIsLabelledClosestStation() {
@@ -375,10 +375,10 @@ final class FuelSavingsEstimateTests: XCTestCase {
             return XCTFail("expected an estimate, got \(String(describing: availability))")
         }
         XCTAssertEqual(result.status, .worthTheDrive)
-        // £60 buys 40 L at 150p; 10p/litre cheaper saves £4.00; 0.4 extra
-        // return miles cost ~£0.09. Net ≈ £3.91.
-        XCTAssertEqual(result.netSavingGBP, 3.909, accuracy: 0.005)
-        XCTAssertEqual(result.headline(compact: true), "Approx. Save £3.91")
+        // £60 buys 37.5 L at 160p; 10p/litre cheaper saves £3.75; 0.4 extra
+        // return miles cost ~£0.09. Net ≈ £3.66.
+        XCTAssertEqual(result.netSavingGBP, 3.659, accuracy: 0.005)
+        XCTAssertEqual(result.headline(compact: true), "Approx. £3.66 better off after travel")
     }
 
     func testNeutralResultHeadlineIsBreakEven() {
@@ -413,7 +413,7 @@ final class FuelSavingsEstimateTests: XCTestCase {
                                        netSavingGBP: 0.52,
                                        status: .worthTheDrive,
                                        distanceBasis: .roadRoute)
-        XCTAssertEqual(saving.headline(), "Save £0.52")
+        XCTAssertEqual(saving.headline(), "£0.52 better off after travel")
 
         let loss = FuelSavingsResult(fillLitres: 34.9,
                                      grossSavingGBP: 1.40,
@@ -422,7 +422,7 @@ final class FuelSavingsEstimateTests: XCTestCase {
                                      netSavingGBP: -0.31,
                                      status: .notWorthTheDrive,
                                      distanceBasis: .roadRoute)
-        XCTAssertEqual(loss.headline(), "Costs £0.31 more")
+        XCTAssertEqual(loss.headline(), "£0.31 worse off after travel")
     }
 
     /// The sort must order by NET saving, not pump price: a pricier station can
@@ -497,7 +497,7 @@ final class FuelSavingsEstimateTests: XCTestCase {
             status: .worthTheDrive,
             distanceBasis: .straightLine
         )
-        XCTAssertEqual(saving.capsuleHeadline(), "Approx. Save £1.00")
+        XCTAssertEqual(saving.capsuleHeadline(), "Approx. £1.00 better off after travel")
 
         let worse = FuelSavingsResult(
             fillLitres: 30,
@@ -507,7 +507,7 @@ final class FuelSavingsEstimateTests: XCTestCase {
             netSavingGBP: -0.31,
             status: .notWorthTheDrive
         )
-        XCTAssertEqual(worse.capsuleHeadline(), "Costs £0.31 more")
+        XCTAssertEqual(worse.capsuleHeadline(), "£0.31 worse off after travel")
     }
 
     // MARK: - Estimate wording (Approx. labels)
@@ -524,7 +524,7 @@ final class FuelSavingsEstimateTests: XCTestCase {
             status: .worthTheDrive,
             distanceBasis: .straightLine
         )
-        XCTAssertEqual(saving.headline(), "Approx. Save £1.25")
+        XCTAssertEqual(saving.headline(), "Approx. £1.25 better off after travel")
 
         let loss = FuelSavingsResult(
             fillLitres: 30,
@@ -535,7 +535,7 @@ final class FuelSavingsEstimateTests: XCTestCase {
             status: .notWorthTheDrive,
             distanceBasis: .straightLine
         )
-        XCTAssertEqual(loss.headline(), "Approx. Costs £0.77 more")
+        XCTAssertEqual(loss.headline(), "Approx. £0.77 worse off after travel")
     }
 
     /// A confirmed road-route comparison must never carry the marker — in either
@@ -551,7 +551,7 @@ final class FuelSavingsEstimateTests: XCTestCase {
             distanceBasis: .roadRoute,
             journeyConfidence: .confirmed
         )
-        XCTAssertEqual(saving.headline(), "Save £1.25")
+        XCTAssertEqual(saving.headline(), "£1.25 better off after travel")
 
         let loss = FuelSavingsResult(
             fillLitres: 30,
@@ -563,7 +563,7 @@ final class FuelSavingsEstimateTests: XCTestCase {
             distanceBasis: .roadRoute,
             journeyConfidence: .confirmed
         )
-        XCTAssertEqual(loss.headline(), "Costs £0.77 more")
+        XCTAssertEqual(loss.headline(), "£0.77 worse off after travel")
 
         for headline in [saving.headline(), loss.headline(), saving.capsuleHeadline()] {
             XCTAssertFalse(headline.contains("Approx"), "\"\(headline)\" must not claim to be an estimate")
@@ -597,7 +597,7 @@ final class FuelSavingsEstimateTests: XCTestCase {
             status: .notWorthTheDrive,
             distanceBasis: .straightLine
         )
-        XCTAssertEqual(estimated.spokenHeadline(), "Approximately Costs £0.77 more")
+        XCTAssertEqual(estimated.spokenHeadline(), "Approximately £0.77 worse off after travel")
 
         XCTAssertEqual(
             FuelSavingsFormat.extraTravelSpokenLabel(extraDistanceMiles: 6.4, unit: .miles, confidence: .estimated),

FuelBoardTests/Tests/FuelBoardSharedTests/FuelSavingsTests.swift

@@ -8,15 +8,15 @@ final class FuelSavingsCalculatorTests: XCTestCase {
         XCTAssertEqual(FuelSavingsCalculator.fuelUsedLitres(distanceMiles: 10, mpg: 45), 1.0102, accuracy: 0.0001)
     }
 
-    func testPoundsBudgetConvertsToLitresUsingGivenPrice() throws {
+    func testPoundsBudgetConvertsToLitresUsingBaselinePrice() throws {
         let amount = FuelSavingsFillAmount(value: 40, unit: .pounds)
-        let litres = try FuelSavingsCalculator.fillLitres(amount: amount, pricePencePerLitre: 160)
+        let litres = try FuelSavingsCalculator.fillLitres(amount: amount, baselinePricePencePerLitre: 160)
         XCTAssertEqual(litres, 25.0, accuracy: 0.0001)
     }
 
     func testLitresAmountPassesThrough() throws {
         let amount = FuelSavingsFillAmount(value: 35, unit: .litres)
-        let litres = try FuelSavingsCalculator.fillLitres(amount: amount, pricePencePerLitre: 160)
+        let litres = try FuelSavingsCalculator.fillLitres(amount: amount, baselinePricePencePerLitre: 160)
         XCTAssertEqual(litres, 35, accuracy: 0.0001)
     }
 
@@ -29,11 +29,11 @@ final class FuelSavingsCalculatorTests: XCTestCase {
             baselineJourneyMiles: 2,
             candidateJourneyMiles: 8
         )
-        XCTAssertEqual(result.fillLitres, 26.6667, accuracy: 0.0001)
-        XCTAssertEqual(result.grossSavingGBP, 2.6667, accuracy: 0.0001)
+        XCTAssertEqual(result.fillLitres, 25, accuracy: 0.0001)
+        XCTAssertEqual(result.grossSavingGBP, 2.50, accuracy: 0.0001)
         XCTAssertEqual(result.extraDistanceMiles, 6, accuracy: 0.0001)
         XCTAssertEqual(result.extraDrivingCostGBP, 0.9092, accuracy: 0.0001)
-        XCTAssertEqual(result.netSavingGBP, 1.7574, accuracy: 0.0001)
+        XCTAssertEqual(result.netSavingGBP, 1.5908, accuracy: 0.0001)
         XCTAssertEqual(result.status, .worthTheDrive)
     }
 
@@ -61,7 +61,7 @@ final class FuelSavingsCalculatorTests: XCTestCase {
     }
 
     func testInvalidInputsRejected() {
-        XCTAssertThrowsError(try FuelSavingsCalculator.fillLitres(amount: FuelSavingsFillAmount(value: 40, unit: .pounds), pricePencePerLitre: 0))
+        XCTAssertThrowsError(try FuelSavingsCalculator.fillLitres(amount: FuelSavingsFillAmount(value: 40, unit: .pounds), baselinePricePencePerLitre: 0))
         XCTAssertThrowsError(try FuelSavingsCalculator.calculate(mpg: 0, amount: FuelSavingsFillAmount(value: 40, unit: .pounds), baselinePricePencePerLitre: 160, candidatePricePencePerLitre: 150, baselineJourneyMiles: 1, candidateJourneyMiles: 2))
         XCTAssertThrowsError(try FuelSavingsCalculator.calculate(mpg: 500, amount: FuelSavingsFillAmount(value: 40, unit: .pounds), baselinePricePencePerLitre: 160, candidatePricePencePerLitre: 150, baselineJourneyMiles: 1, candidateJourneyMiles: 2))
     }

Shared/FuelSavings.swift

@@ -82,7 +82,6 @@ enum JourneyConfidence: String, Codable, Equatable {
 struct FuelSavingsResult: Codable, Equatable {
     let fillLitres: Double
     let grossSavingGBP: Double
-    let extraFuelLitres: Double
     let extraDrivingCostGBP: Double
     let extraDistanceMiles: Double
     let netSavingGBP: Double
@@ -92,7 +91,6 @@ struct FuelSavingsResult: Codable, Equatable {
 
     init(fillLitres: Double,
          grossSavingGBP: Double,
-         extraFuelLitres: Double = 0,
          extraDrivingCostGBP: Double,
          extraDistanceMiles: Double,
          netSavingGBP: Double,
@@ -101,7 +99,6 @@ struct FuelSavingsResult: Codable, Equatable {
          journeyConfidence: JourneyConfidence? = nil) {
         self.fillLitres = fillLitres
         self.grossSavingGBP = grossSavingGBP
-        self.extraFuelLitres = extraFuelLitres
         self.extraDrivingCostGBP = extraDrivingCostGBP
         self.extraDistanceMiles = extraDistanceMiles
         self.netSavingGBP = netSavingGBP
@@ -177,7 +174,6 @@ extension FuelSavingsResult {
         FuelSavingsResult(
             fillLitres: fillLitres,
             grossSavingGBP: 0,
-            extraFuelLitres: 0,
             extraDrivingCostGBP: 0,
             extraDistanceMiles: 0,
             netSavingGBP: 0,
@@ -203,9 +199,9 @@ extension FuelSavingsResult {
         case .breakEven:
             return Self.breakEvenHeadline
         case .worthTheDrive:
-            return "\(prefix)Save \(FuelSavingsFormat.money(netSavingGBP))"
+            return "\(prefix)\(FuelSavingsFormat.money(netSavingGBP)) better off after travel"
         case .notWorthTheDrive:
-            return "\(prefix)Costs \(FuelSavingsFormat.money(abs(netSavingGBP))) more"
+            return "\(prefix)\(FuelSavingsFormat.money(abs(netSavingGBP))) worse off after travel"
         }
     }
 
@@ -325,16 +321,16 @@ enum FuelSavingsCalculator {
         distanceMiles / mpg * imperialGallonLitres
     }
 
-    static func fillLitres(amount: FuelSavingsFillAmount, pricePencePerLitre: Double) throws -> Double {
+    static func fillLitres(amount: FuelSavingsFillAmount, baselinePricePencePerLitre: Double) throws -> Double {
         guard amount.isValid else { throw FuelSavingsError.invalidAmount }
         switch amount.unit {
         case .litres:
             return amount.value
         case .pounds:
-            guard pricePencePerLitre.isFinite, pricePencePerLitre > 0 else {
+            guard baselinePricePencePerLitre.isFinite, baselinePricePencePerLitre > 0 else {
                 throw FuelSavingsError.invalidPrice
             }
-            return amount.value / (pricePencePerLitre / 100.0)
+            return amount.value / (baselinePricePencePerLitre / 100.0)
         }
     }
 
@@ -380,7 +376,7 @@ enum FuelSavingsCalculator {
               baselineJourneyMiles >= 0, candidateJourneyMiles >= 0 else {
             throw FuelSavingsError.invalidDistance
         }
-        let fillLitres = try fillLitres(amount: amount, pricePencePerLitre: candidatePricePencePerLitre)
+        let fillLitres = try fillLitres(amount: amount, baselinePricePencePerLitre: baselinePricePencePerLitre)
         let baselinePriceGBP = baselinePricePencePerLitre / 100.0
         let candidatePriceGBP = candidatePricePencePerLitre / 100.0
         let grossSaving = fillLitres * (baselinePriceGBP - candidatePriceGBP)
@@ -399,7 +395,6 @@ enum FuelSavingsCalculator {
         return FuelSavingsResult(
             fillLitres: fillLitres,
             grossSavingGBP: grossSaving,
-            extraFuelLitres: extraFuelLitres,
             extraDrivingCostGBP: extraFuelCost,
             extraDistanceMiles: extraDistance,
             netSavingGBP: netSaving,