Fetch full-UK dump (no radius/limit); stations in app-group defaults only; alert path keeps focused radius fetch

FuelBoard/ContentView.swift

@@ -200,7 +200,7 @@ struct ContentView: View {
             let fetched = try await FuelPriceProvider.active.fetchStations(
                 near: location?.lat, lng: location?.lng,
                 fuel: selectedFuel,
-                radiusKM: Double(stationLimit) * 1.60934  // miles → km
+                radiusKM: nil  // full-UK dump; device filters by miles radius
             )
             stations = fetched
             FuelStore.saveStations(fetched)

Shared/FuelPriceProvider.swift

@@ -13,9 +13,9 @@ import Foundation
 
 protocol FuelPriceProviding {
     /// Fetch stations with prices. `location` may be nil (sort by price only).
-    /// `radiusKM` bounds the search area (used by the relay). Throws on failure
+    /// `radiusKM` nil = full dataset (device filters); set = focused server-side
-    /// so callers can fall back to cached/sample data.
+    /// radius (alert path). Throws on failure so callers can fall back.
-    func fetchStations(near lat: Double?, lng: Double?, fuel: FuelType, radiusKM: Double) async throws -> [FuelStation]
+    func fetchStations(near lat: Double?, lng: Double?, fuel: FuelType, radiusKM: Double?) async throws -> [FuelStation]
 }
 
 enum FuelPriceProvider {
@@ -32,15 +32,22 @@ enum FuelPriceProvider {
 struct RelayFuelProvider: FuelPriceProviding {
     var baseURL = URL(string: "http://192.168.1.131:8788")!
 
-    func fetchStations(near lat: Double?, lng: Double?, fuel: FuelType, radiusKM: Double) async throws -> [FuelStation] {
+    func fetchStations(near lat: Double?, lng: Double?, fuel: FuelType, radiusKM: Double?) async throws -> [FuelStation] {
         var components = URLComponents(url: baseURL.appendingPathComponent("api/v1/stations"), resolvingAgainstBaseURL: false)!
         var query: [URLQueryItem] = [URLQueryItem(name: "fuel", value: fuel.rawValue)]
         if let lat, let lng {
             query.append(URLQueryItem(name: "lat", value: String(lat)))
             query.append(URLQueryItem(name: "lng", value: String(lng)))
-            query.append(URLQueryItem(name: "radius", value: String(radiusKM)))
         }
+        if let radiusKM {
+            // Focused fetch (alert path) — small response, server-side radius.
+            query.append(URLQueryItem(name: "radius", value: String(radiusKM)))
             query.append(URLQueryItem(name: "limit", value: "500"))
+        } else {
+            // Full-UK dump: NO radius — the device filters locally
+            // (5/10/15-mile radius, fuel, sort). 10,000 covers the dataset.
+            query.append(URLQueryItem(name: "limit", value: "10000"))
+        }
         components.queryItems = query
 
         let (data, response) = try await URLSession.shared.data(from: components.url!)
@@ -107,7 +114,7 @@ private struct RelayResponse: Codable {
 /// Real England-wide data comes from the relay (full-UK Fuel Finder CSV/API).
 /// Prices in pence/litre.
 struct SampleFuelProvider: FuelPriceProviding {
-    func fetchStations(near lat: Double?, lng: Double?, fuel: FuelType, radiusKM: Double) async throws -> [FuelStation] {
+    func fetchStations(near lat: Double?, lng: Double?, fuel: FuelType, radiusKM: Double?) async throws -> [FuelStation] {
         try await Task.sleep(nanoseconds: 300_000_000) // simulate fetch
         return Self.sampleStations
     }
@@ -201,7 +208,7 @@ struct FuelFinderProvider: FuelPriceProviding {
     let clientID: String
     let clientSecret: String
 
-    func fetchStations(near lat: Double?, lng: Double?, fuel: FuelType, radiusKM: Double) async throws -> [FuelStation] {
+    func fetchStations(near lat: Double?, lng: Double?, fuel: FuelType, radiusKM: Double?) async throws -> [FuelStation] {
         // TODO: OAuth token → GET /v1/prices → map to FuelStation.
         // The live API requires authentication; see notes above.
         throw FuelProviderError.notImplemented

Shared/FuelStore.swift

@@ -147,15 +147,19 @@ struct FuelStore {
     static let lastRefreshKey = "fuelboard.lastRefresh"      // TimeInterval (seconds since 1970)
 
     // MARK: Stations
+    // The full-UK dataset (~2.9 MB) lives in app-group UserDefaults only —
+    // keychain is for small values and cannot hold it. Read order is
+    // defaults-first for stations (keychain may hold a legacy small set from
+    // older builds; the full country dump always wins).
 
     static func loadStations() -> [FuelStation] {
-        if let data = keychainData(service: stationsKey),
+        if let defaults = UserDefaults(suiteName: appGroupSuite),
+           let data = defaults.data(forKey: stationsKey),
            let stations = try? JSONDecoder().decode([FuelStation].self, from: data),
            !stations.isEmpty {
             return stations
         }
-        if let defaults = UserDefaults(suiteName: appGroupSuite),
+        if let data = keychainData(service: stationsKey),
-           let data = defaults.data(forKey: stationsKey),
            let stations = try? JSONDecoder().decode([FuelStation].self, from: data),
            !stations.isEmpty {
             return stations
@@ -166,7 +170,7 @@ struct FuelStore {
     static func saveStations(_ stations: [FuelStation]) {
         if let data = try? JSONEncoder().encode(stations) {
             UserDefaults(suiteName: appGroupSuite)?.set(data, forKey: stationsKey)
-            writeKeychain(data: data, service: stationsKey)
+            // Intentionally NOT written to keychain — 2.9 MB exceeds its limits.
         }
     }