Closest mode: deltas vs the CLOSEST station (signed +X.Xp/-X.Xp), not the nationwide cheapest; baseline = sortedStations.first

FuelBoard/ContentView.swift

@@ -36,8 +36,15 @@ struct ContentView: View {
         }
     }
 
-    private var cheapestPrice: Double? {
-        poolStations.compactMap { $0.prices[selectedFuel] }.min()
+    /// The price reference every row's delta + RAG compares against.
+    /// Cheapest mode → the cheapest station in the pool (best value).
+    /// Closest mode → the CLOSEST station: deltas answer "is it worth leaving
+    /// the station nearest to me?" (+X.Xp pricier / -X.Xp cheaper).
+    private var baselinePrice: Double? {
+        if sortMode == .closest {
+            return sortedStations.first?.prices[selectedFuel]
+        }
+        return poolStations.compactMap { $0.prices[selectedFuel] }.min()
     }
 
     private var displayedStations: [FuelStation] {
@@ -86,7 +93,7 @@ struct ContentView: View {
                 selectedFuel: $selectedFuel,
                 sortMode: $sortMode,
                 stationLimit: $stationLimit,
-                cheapestPrice: cheapestPrice,
+                baselinePrice: baselinePrice,
                 location: location,
                 favouriteIDs: favouriteIDs,
                 onToggleFavourite: toggleFavourite,
@@ -214,14 +221,14 @@ struct StationRow: View {
     let station: FuelStation
     let fuel: FuelType
     let location: Coordinate?
-    let cheapestPrice: Double?
+    let baselinePrice: Double?
     let isTopResult: Bool
     let isFavourite: Bool
     var onToggleFavourite: () -> Void = {}
 
     private var ragColor: Color {
-        guard let price = station.prices[fuel], let cheapestPrice else { return .gray }
-        switch RAGRating.rating(price: price, cheapest: cheapestPrice) {
+        guard let price = station.prices[fuel], let baselinePrice else { return .gray }
+        switch RAGRating.rating(price: price, cheapest: baselinePrice) {
         case .green: return .green
         case .amber: return .orange
         case .red: return .red
@@ -229,10 +236,12 @@ struct StationRow: View {
     }
 
     private var deltaText: String? {
-        guard let price = station.prices[fuel], let cheapestPrice else { return nil }
-        let delta = price - cheapestPrice
-        if delta <= 0.05 { return "best" }
-        return String(format: "+%.1fp", delta)
+        guard let price = station.prices[fuel], let baselinePrice else { return nil }
+        let delta = price - baselinePrice
+        if abs(delta) <= 0.05 { return "best" }
+        // Signed: +X.Xp pricier than baseline, -X.Xp cheaper (Closest mode);
+        // in Cheapest mode the baseline is the cheapest so deltas are ≥ 0.
+        return String(format: "%+.1fp", delta)
     }
 
     var body: some View {