Add first-run onboarding guide

LoopFollow/Alarm/AlarmListView.swift

@@ -154,6 +154,9 @@ struct AlarmListView: View {
             AddAlarmSheet { type in
                 let new = Alarm(type: type)
                 store.value.append(new)
+                // First alarm the user adds is the moment notifications become
+                // useful — request authorization here rather than at app launch.
+                NotificationAuthorization.requestIfNeeded()
                 sheetInfo = .editor(id: new.id, isNew: true)
             }
 

LoopFollow/Application/AppDelegate.swift

@@ -2,7 +2,6 @@
 // AppDelegate.swift
 
 import AVFoundation
-import EventKit
 import UIKit
 import UserNotifications
 
@@ -13,29 +12,25 @@ class AppDelegate: UIResponder, UIApplicationDelegate {
         LogManager.shared.log(category: .general, message: "App started")
         LogManager.shared.cleanupOldLogs()
 
-        let options: UNAuthorizationOptions = [.alert, .sound, .badge]
-        notificationCenter.requestAuthorization(options: options) {
-            didAllow, _ in
-            if !didAllow {
-                LogManager.shared.log(category: .general, message: "User has declined notifications")
-            }
-        }
-
-        let store = EKEventStore()
-        store.requestCalendarAccess { granted, error in
-            if !granted {
-                LogManager.shared.log(category: .calendar, message: "Failed to get calendar access: \(String(describing: error))")
-                return
-            }
-        }
+        // Notification and calendar permissions are no longer requested here.
+        // They're deferred to the moment the user opts into the feature that
+        // needs them (alarms request notifications via NotificationAuthorization;
+        // the Calendar settings screen requests calendar access), so a fresh
+        // install isn't fronted with permission prompts before onboarding.
 
         let action = UNNotificationAction(identifier: "OPEN_APP_ACTION", title: "Open App", options: .foreground)
         let category = UNNotificationCategory(identifier: BackgroundAlertIdentifier.categoryIdentifier, actions: [action], intentIdentifiers: [], options: [])
         UNUserNotificationCenter.current().setNotificationCategories([category])
 
         UNUserNotificationCenter.current().delegate = self
 
-        _ = BLEManager.shared
+        // Only spin up Bluetooth if the user has chosen a BLE-based background
+        // refresh. Initializing BLEManager creates a CBCentralManager, which
+        // triggers the Bluetooth permission prompt — deferring it keeps that
+        // prompt off fresh installs until the feature is actually enabled.
+        if Storage.shared.backgroundRefreshType.value.isBluetooth {
+            _ = BLEManager.shared
+        }
         // Ensure VolumeButtonHandler is initialized so it can receive alarm notifications
         _ = VolumeButtonHandler.shared
 

LoopFollow/Application/MainTabView.swift

@@ -15,6 +15,7 @@ struct MainTabView: View {
     @ObservedObject private var treatmentsPosition = Storage.shared.treatmentsPosition
 
     @State private var showTelemetryConsent = false
+    @State private var showOnboarding = false
 
     private var orderedItems: [TabItem] {
         Storage.shared.orderedTabBarItems()
@@ -47,21 +48,38 @@ struct MainTabView: View {
             // onAppear (not app launch) keeps it off the BG-only refresh path.
             MainViewController.bootstrap()
 
-            // One-time consent prompt. Previously presented by SceneDelegate,
-            // which was removed in the storyboard→SwiftUI migration; without
-            // this, fresh installs stay permanently undecided and telemetry
-            // never sends. The storage flag keeps it to a single appearance.
-            if !Storage.shared.telemetryConsentDecisionMade.value {
-                showTelemetryConsent = true
+            // Show the first-run onboarding once for everyone. Returning users
+            // get a prominent Skip on the welcome screen. The telemetry consent
+            // prompt is deferred until onboarding is dismissed so the two never
+            // appear on top of one another.
+            if !Storage.shared.hasCompletedOnboarding.value {
+                showOnboarding = true
+            } else {
+                presentTelemetryConsentIfNeeded()
             }
         }
+        .fullScreenCover(isPresented: $showOnboarding, onDismiss: {
+            presentTelemetryConsentIfNeeded()
+        }) {
+            OnboardingContainerView(onClose: { showOnboarding = false })
+        }
         .sheet(isPresented: $showTelemetryConsent) {
             // User must explicitly choose — no swipe-to-dismiss.
             TelemetryConsentView()
                 .interactiveDismissDisabled(true)
         }
     }
 
+    // One-time telemetry consent prompt. Previously presented by SceneDelegate,
+    // which was removed in the storyboard→SwiftUI migration; without this, fresh
+    // installs stay permanently undecided and telemetry never sends. The storage
+    // flag keeps it to a single appearance.
+    private func presentTelemetryConsentIfNeeded() {
+        if !Storage.shared.telemetryConsentDecisionMade.value {
+            showTelemetryConsent = true
+        }
+    }
+
     @ViewBuilder
     private func tabContent(for item: TabItem) -> some View {
         switch item {

LoopFollow/BackgroundRefresh/BT/BLEManager.swift

@@ -8,13 +8,20 @@ import Foundation
 class BLEManager: NSObject, ObservableObject {
     static let shared = BLEManager()
 
+    /// Whether the shared instance has been created (and therefore a
+    /// CBCentralManager exists / the Bluetooth prompt has been triggered).
+    /// Reading this does not instantiate `shared`, so callers can avoid forcing
+    /// Bluetooth initialization — and its permission prompt — when not needed.
+    private(set) static var isInitialized = false
+
     @Published private(set) var devices: [BLEDevice] = []
 
     private var centralManager: CBCentralManager!
     private var activeDevice: BluetoothDevice?
 
     override private init() {
         super.init()
+        BLEManager.isInitialized = true
 
         centralManager = CBCentralManager(
             delegate: self,

LoopFollow/BackgroundRefresh/BackgroundRefreshSettingsViewModel.swift

@@ -33,6 +33,12 @@ class BackgroundRefreshSettingsViewModel: ObservableObject {
     private func handleBackgroundRefreshTypeChange(_ newValue: BackgroundRefreshType) {
         LogManager.shared.log(category: .general, message: "Background refresh type changed to: \(newValue.rawValue)")
 
-        BLEManager.shared.disconnect()
+        // Touch BLEManager only when switching to a Bluetooth mode (the user is
+        // opting in, so the permission prompt belongs here) or when it's already
+        // running and needs to be torn down. Switching between non-BLE modes must
+        // not initialize Bluetooth — that would prompt without cause.
+        if newValue.isBluetooth || BLEManager.isInitialized {
+            BLEManager.shared.disconnect()
+        }
     }
 }

LoopFollow/Controllers/BackgroundAlertManager.swift

@@ -76,7 +76,10 @@ class BackgroundAlertManager {
         removeDeliveredNotifications()
 
         let isBluetoothActive = Storage.shared.backgroundRefreshType.value.isBluetooth
-        let expectedHeartbeat = BLEManager.shared.expectedHeartbeatInterval()
+        // Only query BLEManager for a Bluetooth mode — touching it otherwise would
+        // initialize CoreBluetooth and trigger the permission prompt for users
+        // (e.g. Silent Tune) who never opted into Bluetooth.
+        let expectedHeartbeat = isBluetoothActive ? BLEManager.shared.expectedHeartbeatInterval() : nil
 
         // Define alerts
         let alerts: [BackgroundAlert] = [

LoopFollow/Helpers/NightscoutUtils.swift

@@ -1,6 +1,7 @@
 // LoopFollow
 // NightscoutUtils.swift
 
+import CryptoKit
 import Foundation
 
 class NightscoutUtils {
@@ -385,6 +386,125 @@ class NightscoutUtils {
         return responseString
     }
 
+    // MARK: - Token Provisioning
+
+    /// Name of the Nightscout authorization subject LoopFollow creates when a
+    /// user provisions a token from their API secret.
+    static let provisionedSubjectName = "LoopFollow"
+
+    private struct AuthSubject: Decodable {
+        let id: String?
+        let name: String?
+        let accessToken: String?
+        let roles: [String]?
+
+        enum CodingKeys: String, CodingKey {
+            case id = "_id"
+            case name, accessToken, roles
+        }
+    }
+
+    /// Creates (or reuses) a read-only Nightscout access token using the site's
+    /// API secret. The secret only authorizes these requests and is never
+    /// persisted. Returns the access token for a `readable` subject named
+    /// `provisionedSubjectName`.
+    ///
+    /// The full API secret authenticates as Nightscout's `admin` role (the `*`
+    /// permission), which includes `admin:api:subjects:create`.
+    ///
+    /// Nightscout serves the subjects list from an in-memory cache that doesn't
+    /// refresh promptly after a write, so a freshly-created subject (and its
+    /// token) can't be read back reliably right after creating it. Instead we
+    /// derive the token locally: it's a pure function of the subject's `_id`
+    /// (returned by the create call) and the API secret. See `accessToken(for:)`.
+    static func provisionReadOnlyToken(url: String, secret: String) async throws -> String {
+        let trimmedURL = url.trimmingCharacters(in: .whitespacesAndNewlines)
+        guard !trimmedURL.isEmpty else { throw NightscoutError.emptyAddress }
+        guard let baseURL = URL(string: trimmedURL),
+              trimmedURL.hasPrefix("http://") || trimmedURL.hasPrefix("https://")
+        else { throw NightscoutError.invalidURL }
+
+        let secretHash = sha1Hex(secret)
+
+        // Reuse an existing subject if one is already visible (idempotent re-runs
+        // once the site's cache has caught up).
+        if let existing = try await fetchProvisionedToken(baseURL: baseURL, secretHash: secretHash) {
+            return existing
+        }
+
+        let id = try await createReadOnlySubject(baseURL: baseURL, secretHash: secretHash)
+        return accessToken(forName: provisionedSubjectName, id: id, secretHash: secretHash)
+    }
+
+    private static func fetchProvisionedToken(baseURL: URL, secretHash: String) async throws -> String? {
+        let url = baseURL.appendingPathComponent("api/v2/authorization/subjects")
+        var request = URLRequest(url: url)
+        request.httpMethod = "GET"
+        request.setValue(secretHash, forHTTPHeaderField: "api-secret")
+        request.setValue("application/json", forHTTPHeaderField: "Accept")
+        request.cachePolicy = .reloadIgnoringLocalCacheData
+
+        let (data, response) = try await URLSession.shared.data(for: request)
+        try validateProvisioningResponse(response)
+
+        let subjects = try JSONDecoder().decode([AuthSubject].self, from: data)
+        return subjects.first(where: { $0.name == provisionedSubjectName })?.accessToken
+    }
+
+    /// Creates the subject and returns its `_id`.
+    private static func createReadOnlySubject(baseURL: URL, secretHash: String) async throws -> String {
+        let url = baseURL.appendingPathComponent("api/v2/authorization/subjects")
+        var request = URLRequest(url: url)
+        request.httpMethod = "POST"
+        request.setValue(secretHash, forHTTPHeaderField: "api-secret")
+        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
+        request.httpBody = try JSONSerialization.data(withJSONObject: [
+            "name": provisionedSubjectName,
+            "roles": ["readable"],
+        ])
+
+        let (data, response) = try await URLSession.shared.data(for: request)
+        try validateProvisioningResponse(response)
+
+        let subject = try JSONDecoder().decode(AuthSubject.self, from: data)
+        guard let id = subject.id, !id.isEmpty else { throw NightscoutError.unknown }
+        return id
+    }
+
+    /// Reproduces Nightscout's subject-token derivation (`lib/authorization`):
+    ///   abbrev = name lowercased, non-`\w` characters removed, first 10 chars
+    ///   digest = sha1( sha1Hex(apiSecret) + subjectId )
+    ///   token  = "\(abbrev)-\(digest[0..<16])"
+    private static func accessToken(forName name: String, id: String, secretHash: String) -> String {
+        let allowed = Set("abcdefghijklmnopqrstuvwxyz0123456789_")
+        let abbrev = String(name.lowercased().filter { allowed.contains($0) }.prefix(10))
+        let digest = sha1Hex(secretHash + id)
+        return abbrev + "-" + String(digest.prefix(16))
+    }
+
+    private static func validateProvisioningResponse(_ response: URLResponse) throws {
+        guard let http = response as? HTTPURLResponse else {
+            throw NightscoutError.networkError
+        }
+        switch http.statusCode {
+        case 200 ..< 300:
+            return
+        case 401, 403:
+            // The API secret was missing or wrong.
+            throw NightscoutError.invalidToken
+        case 404:
+            throw NightscoutError.siteNotFound
+        default:
+            throw NightscoutError.unknown
+        }
+    }
+
+    private static func sha1Hex(_ string: String) -> String {
+        Insecure.SHA1.hash(data: Data(string.utf8))
+            .map { String(format: "%02x", $0) }
+            .joined()
+    }
+
     static func extractErrorReason(from responseString: String) -> String {
         // 1) Try to parse the entire string as JSON and return the "message"
         if let data = responseString.data(using: .utf8) {

LoopFollow/Helpers/NotificationAuthorization.swift

@@ -0,0 +1,23 @@
+// LoopFollow
+// NotificationAuthorization.swift
+
+import UserNotifications
+
+/// Requests notification authorization lazily, the first time the user opts into
+/// a feature that needs it (alarms). This keeps the system prompt off the very
+/// first launch so it doesn't front the onboarding flow.
+enum NotificationAuthorization {
+    /// Asks for authorization only when the user hasn't decided yet. Safe to call
+    /// repeatedly — it's a no-op once the status is determined.
+    static func requestIfNeeded() {
+        let center = UNUserNotificationCenter.current()
+        center.getNotificationSettings { settings in
+            guard settings.authorizationStatus == .notDetermined else { return }
+            center.requestAuthorization(options: [.alert, .sound, .badge]) { granted, _ in
+                if !granted {
+                    LogManager.shared.log(category: .general, message: "User has declined notifications")
+                }
+            }
+        }
+    }
+}