Live Activity: cheapest-in-radius Lock Screen/Dynamic Island pill

- Shared FuelBoardLiveActivityAttributes/ContentState (app + widget targets) - FuelBoardLiveActivity Widget: ActivityConfiguration rendered by the widget extension - Lock Screen banner + Dynamic Island (leading/trailing/bottom, compact, minimal), tap anywhere -> maps:// directions to the best station - LiveActivityManager (app side): request/update/end; mirrors the app list's TOP badge (selected fuel + chosen distance radius, price-then-distance ties); local start-date tracking for the 8h cap (this SDK's Activity has no startDate) - auto-restarts at 7h59m; silent no-op when disabled/denied - Wiring: 250m/60s location hook (incl. background significant-change wake-ups), refresh completion, fuel/radius/unit changes, toggle flip - Settings toggle + FuelStore persistence (keychain-backed, app-group) - App-Info.plist: NSSupportsLiveActivities
2026-08-12 20:11:27 +01:00
parent 1dcd47c6cd
commit c362d562d7
8 changed files with 362 additions and 0 deletions
@@ -0,0 +1,127 @@
+// LiveActivityManager.swift — app-side driver for the FuelBoard Live Activity.
+//
+// The app owns the activity lifecycle (request / update / end) because the
+// activity's own sandbox cannot fetch prices or read location. It mirrors the
+// app's TOP badge exactly: cheapest station selling the SELECTED fuel within
+// the CHOSEN distance radius. Call sites:
+//   - every location fix (foreground AND background significant-change wake-ups)
+//   - after every station refresh
+//   - when the Settings toggle flips
+//
+// Live Activities auto-end after 8 h — this manager re-requests a fresh one
+// just before the cap so a long drive keeps its glanceable pill.
+
+import ActivityKit
+import Foundation
+
+@MainActor
+enum LiveActivityManager {
+    /// The running activity, if any.
+    private static var current: Activity<FuelBoardLiveActivityAttributes>?
+    /// When `current` was requested. This SDK's `Activity` no longer exposes
+    /// `startDate`, so the manager tracks it locally to honour the 8 h cap.
+    private static var currentStartDate: Date?
+
+    /// The system ends Live Activities after 8 hours. Restart at 7h59m so the
+    /// pill never silently disappears mid-drive.
+    private static let restartThreshold: TimeInterval = 7 * 3600 + 59 * 60
+
+    /// Recomputes the cheapest-in-radius station and updates the activity.
+    /// Passing `enabled: false` (or no usable data) ends any running activity.
+    static func update(
+        stations: [FuelStation],
+        fuel: FuelType,
+        radiusKM: Double,
+        location: Coordinate?,
+        enabled: Bool
+    ) {
+        guard enabled, let location else {
+            end()
+            return
+        }
+        guard let best = cheapestStation(
+            stations: stations, fuel: fuel, radiusKM: radiusKM,
+            lat: location.lat, lng: location.lng
+        ), let price = best.prices[fuel] else {
+            end()
+            return
+        }
+
+        let state = FuelBoardLiveActivityAttributes.ContentState(
+            stationID: best.id,
+            stationName: best.name,
+            brand: best.brand,
+            pricePence: price,
+            distanceKM: best.distanceKM(to: location.lat, lng2: location.lng),
+            lat: best.lat,
+            lng: best.lng,
+            updatedAt: Date()
+        )
+        let attributes = FuelBoardLiveActivityAttributes(fuel: fuel)
+
+        if let current {
+            // Near the 8 h cap? End and re-request so the pill keeps living.
+            let age = currentStartDate.map { Date().timeIntervalSince($0) } ?? 0
+            if age >= restartThreshold {
+                Task { await current.end(nil, dismissalPolicy: .immediate) }
+                self.current = nil
+                currentStartDate = nil
+                start(attributes: attributes, state: state)
+            } else {
+                Task { await current.update(using: state) }
+            }
+        } else {
+            start(attributes: attributes, state: state)
+        }
+    }
+
+    /// Ends any running activity (toggle off / app reset).
+    static func end() {
+        guard let current else { return }
+        Task { await current.end(nil, dismissalPolicy: .immediate) }
+        self.current = nil
+        currentStartDate = nil
+    }
+
+    // MARK: - Internals
+
+    private static func start(
+        attributes: FuelBoardLiveActivityAttributes,
+        state: FuelBoardLiveActivityAttributes.ContentState
+    ) {
+        do {
+            current = try Activity.request(
+                attributes: attributes,
+                content: .init(state: state, staleDate: nil),
+                pushType: nil
+            )
+            currentStartDate = Date()
+        } catch {
+            // User disabled Live Activities in Settings, or system budget —
+            // silent: the feature just doesn't appear.
+            current = nil
+            currentStartDate = nil
+        }
+    }
+
+    /// Cheapest station selling `fuel` within `radiusKM` of the location —
+    /// identical semantics to the app list's TOP badge (price first, then
+    /// distance as the tie-breaker).
+    static func cheapestStation(
+        stations: [FuelStation],
+        fuel: FuelType,
+        radiusKM: Double,
+        lat: Double,
+        lng: Double
+    ) -> FuelStation? {
+        stations
+            .filter { $0.prices[fuel] != nil }
+            .filter { $0.distanceKM(to: lat, lng2: lng) <= radiusKM }
+            .min { lhs, rhs in
+                let lPrice = lhs.prices[fuel]!
+                let rPrice = rhs.prices[fuel]!
+                if lPrice != rPrice { return lPrice < rPrice }
+                return lhs.distanceKM(to: lat, lng2: lng) < rhs.distanceKM(to: lat, lng2: lng)
+            }
+    }
+}