fix(ios): pair from one iPhone with a code, link or QR picture

README.md

@@ -63,8 +63,11 @@ iOS 26 is the minimum. iPhone only.
 
 - Pair: camera QR, a link from outside shown before it is trusted (also a
   pairing QR scanned with the iOS camera, as a universal link), and the live
-  demo against a simulated box. In the simulator, which has no camera, a
-  picture of the QR from Photos takes the same path.
+  demo against a simulated box. A QR picture from Photos works on an iPhone
+  too. Enter pairing code accepts a full pairing link, or a short code and
+  the box's local address. The short-code path needs
+  [Core #1721](https://github.com/srcfl/ftw/pull/1721) and the home Wi-Fi;
+  it asks for the house password when the box requires it.
 - Now: one sentence, the energy flow, the price card with the cheapest two
   hours, today's totals and the fuse. The freshness band above it keeps
   carrier and source state apart.

appleApp/FTW-Info.plist

@@ -2,6 +2,13 @@
 <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 <plist version="1.0">
 <dict>
+	<key>NSLocalNetworkUsageDescription</key>
+	<string>FTW connects to your box on your home network to exchange the pairing code.</string>
+	<key>NSAppTransportSecurity</key>
+	<dict>
+		<key>NSAllowsLocalNetworking</key>
+		<true/>
+	</dict>
 	<key>FTWAppGroup</key>
 	<string>$(FTW_APP_GROUP)</string>
 	<key>BGTaskSchedulerPermittedIdentifiers</key>

appleApp/FTW/Intents/en.lproj/InfoPlist.strings

@@ -0,0 +1 @@
+"NSLocalNetworkUsageDescription" = "FTW connects to your box on your home network to exchange the pairing code.";

appleApp/FTW/Intents/sv.lproj/InfoPlist.strings

@@ -0,0 +1 @@
+"NSLocalNetworkUsageDescription" = "FTW ansluter till din box på hemnätet för att byta in parkoden.";

appleApp/FTW/UI/PairView.swift

@@ -1,8 +1,6 @@
 import FTWKit
 import SwiftUI
-#if targetEnvironment(simulator)
 import PhotosUI
-#endif
 
 /// Pairing, the first thing anyone sees. Scan, then Face ID. Everything that
 /// can fail does so before the passkey prompt.
@@ -13,9 +11,7 @@ import PhotosUI
 struct PairView: View {
     let app: AppModel
     @State private var model: PairModel
-    #if targetEnvironment(simulator)
     @State private var picture: PhotosPickerItem?
-    #endif
 
     init(app: AppModel) {
         self.app = app
@@ -55,6 +51,7 @@ struct PairView: View {
     private var title: String {
         switch model.stage {
         case .scanning: return L("Scan the pairing QR")
+        case .enteringCode: return L("Enter pairing code")
         case .pairing: return L("Securing this phone")
         case .demoing: return L("Starting the demo")
         case .intro:
@@ -74,6 +71,41 @@ struct PairView: View {
                 .overlay(RoundedRectangle(cornerRadius: 24).strokeBorder(Theme.accentFill, lineWidth: 3).padding(60))
             Hint(L("In your box's local dashboard, open Settings → FTW app. Hold the pairing QR inside the frame."))
 
+        case .enteringCode:
+            Text(L("Stay on your home Wi-Fi.")).font(.callout)
+            Text(L("Box address")).font(.caption).foregroundStyle(Theme.ink2)
+            TextField(L("Box address"), text: $model.boxAddress)
+                .textFieldStyle(.roundedBorder)
+                .textContentType(.URL)
+                .textInputAutocapitalization(.never)
+                .autocorrectionDisabled()
+                .keyboardType(.URL)
+                .accessibilityIdentifier("pair.address")
+            Text(L("Pairing code")).font(.caption).foregroundStyle(Theme.ink2)
+            TextField(L("Pairing code"), text: $model.code)
+                .textFieldStyle(.roundedBorder)
+                .textInputAutocapitalization(.characters)
+                .autocorrectionDisabled()
+                .accessibilityIdentifier("pair.code")
+            PasteButton(payloadType: String.self) { values in
+                if let value = values.first { model.code = value }
+            }
+            if model.needsPassword {
+                SecureField(L("House password"), text: $model.password)
+                    .textContentType(.password)
+                    .accessibilityIdentifier("pair.password")
+            }
+            if let message = model.message { Problem(message) }
+            if model.codeBusy { ProgressView(L("Connecting to your box")) }
+            DisclosureGroup(L("How?")) {
+                VStack(alignment: .leading, spacing: 8) {
+                    Text(L("On this iPhone, open your box in Safari. In Settings → FTW app, choose Use a pairing code. Return here and enter it while on your home Wi-Fi."))
+                    Hint(L("Copying the code in Safari includes the box address. You can also paste a full pairing link here."))
+                }
+                .font(.callout)
+                .padding(.top, 6)
+            }
+
         case .pairing:
             Text(L("Confirm with Face ID or Touch ID if your phone asks."))
             ProgressView()
@@ -95,6 +127,10 @@ struct PairView: View {
     /// quiet way out.
     @ViewBuilder private var actions: some View {
         switch model.stage {
+        case .enteringCode:
+            prominent(L("Connect")) { Task { await model.connectCode() } }
+                .disabled(model.codeBusy || model.code.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty)
+            Button(L("Cancel")) { model.cancel() }.buttonStyle(.quiet)
         case .scanning, .pairing:
             Button(L("Cancel")) { model.cancel() }
                 .buttonStyle(.glass)
@@ -110,8 +146,12 @@ struct PairView: View {
             } else if model.canOpen, let known = model.known {
                 prominent(NodeWords.format("Open %@", known.label)) { model.openKnown() }
                 Button(L("Scan a new pairing QR")) { model.stage = .scanning }.buttonStyle(.quiet)
+                Button(L("Enter pairing code")) { model.enterCode() }.buttonStyle(.quiet)
             } else {
                 prominent(L("Scan the pairing QR")) { model.stage = .scanning }
+                Button(L("Enter pairing code")) { model.enterCode() }
+                    .buttonStyle(.quiet)
+                    .accessibilityIdentifier("pair.enterCode")
                 if canDismiss {
                     Button(L("Not now")) { model.dismiss() }.buttonStyle(.quiet)
                 }
@@ -189,7 +229,7 @@ struct PairView: View {
     private var setup: some View {
         Card {
             Text(L("Connect your own box")).font(.title3.weight(.semibold))
-            Text(L("At home, open your box's FTW dashboard, then Settings → FTW app → Show pairing code."))
+            Text(L("Have only this iPhone? Open the box in Safari, then Settings → FTW app. Open the pairing link in FTW or use a pairing code."))
                 .font(.callout)
             DisclosureGroup(L("How?")) {
                 VStack(alignment: .leading, spacing: 6) {
@@ -198,25 +238,21 @@ struct PairView: View {
                     Text(L("3. Choose Show pairing code, then scan the QR here."))
                     Hint(L("The QR code is inside FTW Settings. It is not printed on the Raspberry Pi or its case."))
                     Hint(L("Next, your phone asks for Face ID or Touch ID to protect your FTW key. There is no FTW account or password. If this phone loses its key, a new Settings QR is the way back."))
-                    Hint(L("Can't see Show pairing code? Turn on Let the FTW app connect to this box, save, and restart the box first."))
+                    Hint(L("Can't see Show pairing code? Turn on Let the FTW app connect to this box, then choose Save and restart FTW in the dashboard."))
                 }
                 .font(.callout)
                 .frame(maxWidth: .infinity, alignment: .leading)
                 .padding(.top, 6)
             }
             .font(.footnote.weight(.medium))
-            #if targetEnvironment(simulator)
-            // The simulator has no camera. A screenshot of the QR in Photos
-            // takes the same path as a scan.
             PhotosPicker(L("Choose a picture of the QR"), selection: $picture, matching: .images)
                 .buttonStyle(.quiet)
+                .accessibilityIdentifier("pair.picture")
                 .onChange(of: picture) { _, item in read(item) }
-            #endif
         }
     }
 }
 
-#if targetEnvironment(simulator)
 extension PairView {
     private func read(_ item: PhotosPickerItem?) {
         guard let item else { return }
@@ -231,7 +267,6 @@ extension PairView {
         }
     }
 }
-#endif
 
 struct Title: View {
     let text: String

appleApp/FTWKit/Sources/FTWKit/Identity/Enrollment.swift

@@ -11,7 +11,8 @@ import Foundation
 /// service"). Both are read.
 ///
 /// Everything after `#` is a fragment and never sent in a request, so the
-/// trust anchor reaches the phone optically and reaches no server on the way.
+/// trust anchor reaches the phone from the box: a QR, a link, a paste, or a
+/// local code exchange. It reaches no cloud server on the way.
 public struct Enrollment: Equatable, Sendable {
     /// The box's Noise static public key. The trust anchor.
     public var boxStaticPublic: Bytes

appleApp/FTWKit/Sources/FTWKit/Identity/LocalPairing.swift

@@ -0,0 +1,115 @@
+import Foundation
+import Network
+
+/// A short code is exchanged directly with the box on the home network.
+/// Its full enrollment link then follows the same path as a camera scan.
+public struct LocalPairing: Sendable {
+    public typealias Send = @Sendable (URLRequest) async throws -> (Data, HTTPURLResponse)
+    private let send: Send
+
+    public init(send: @escaping Send = LocalPairing.request) { self.send = send }
+
+    public func redeem(address: String, code: String, password: String = "") async throws -> String {
+        let input = try Self.input(address: address, code: code)
+        var request = URLRequest(url: input.url, cachePolicy: .reloadIgnoringLocalCacheData, timeoutInterval: 20)
+        request.httpMethod = "POST"
+        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
+        if !password.isEmpty { request.setValue("Bearer \(password)", forHTTPHeaderField: "Authorization") }
+        request.httpBody = try JSONEncoder().encode(Claim(kind: "claim", code: input.code))
+        let (data, response): (Data, HTTPURLResponse)
+        do { (data, response) = try await send(request) }
+        catch is CancellationError { throw CancellationError() }
+        catch { throw LocalPairingError.unreachable }
+        if response.statusCode == 401 { throw LocalPairingError.password }
+        guard response.statusCode == 200 else {
+            throw response.statusCode == 400 ? LocalPairingError.code : LocalPairingError.unavailable
+        }
+        guard data.count < 8_192, let reply = try? JSONDecoder().decode(Reply.self, from: data),
+              (try? Enrollment.parse(scanned: reply.url)) != nil else { throw LocalPairingError.unavailable }
+        return reply.url
+    }
+
+    /// Copying the code on the box includes its address as a fragment. The
+    /// code never becomes a URL path or query, including while it is pasted.
+    static func input(address: String, code: String) throws -> (url: URL, code: String) {
+        var host = address.trimmingCharacters(in: .whitespacesAndNewlines)
+        var typed = code.trimmingCharacters(in: .whitespacesAndNewlines)
+        if let pasted = URLComponents(string: typed), pasted.scheme != nil, let fragment = pasted.fragment {
+            var box = pasted
+            box.fragment = nil
+            host = box.string ?? ""
+            typed = fragment
+        }
+        let canonical = typed.uppercased().filter { !$0.isWhitespace && $0 != "-" }
+            .replacingOccurrences(of: "O", with: "0")
+            .replacingOccurrences(of: "I", with: "1")
+            .replacingOccurrences(of: "L", with: "1")
+        guard canonical.count == 8, canonical.allSatisfy({ "0123456789ABCDEFGHJKMNPQRSTVWXYZ".contains($0) }) else {
+            throw LocalPairingError.code
+        }
+        if !host.contains("://") { host = "http://" + host }
+        guard var target = URLComponents(string: host),
+              ["http", "https"].contains(target.scheme?.lowercased() ?? ""),
+              let hostname = target.host, Self.localHost(hostname),
+              target.user == nil, target.password == nil, target.query == nil, target.fragment == nil,
+              target.path.isEmpty || target.path == "/",
+              target.port == nil || (1...65535).contains(target.port!) else { throw LocalPairingError.address }
+        target.path = "/api/app-link/pairing"
+        guard let url = target.url else { throw LocalPairingError.address }
+        return (url, canonical)
+    }
+
+    private static func localHost(_ host: String) -> Bool {
+        let name = host.lowercased().trimmingCharacters(in: CharacterSet(charactersIn: "[]"))
+        if name == "localhost" || name.hasSuffix(".local") || name.hasSuffix(".localhost") || name.hasSuffix(".home.arpa") { return true }
+        if let address = IPv4Address(name) {
+            let b = Array(address.rawValue)
+            return b[0] == 10 || b[0] == 127 || (b[0] == 172 && (16...31).contains(b[1])) ||
+                (b[0] == 192 && b[1] == 168) || (b[0] == 169 && b[1] == 254)
+        }
+        if let address = IPv6Address(name) {
+            let b = Array(address.rawValue)
+            return address == .loopback || b[0] & 0xfe == 0xfc || (b[0] == 0xfe && b[1] & 0xc0 == 0x80)
+        }
+        return false
+    }
+
+    public static func request(_ request: URLRequest) async throws -> (Data, HTTPURLResponse) {
+        let configuration = URLSessionConfiguration.ephemeral
+        configuration.urlCache = nil
+        configuration.httpCookieStorage = nil
+        configuration.urlCredentialStorage = nil
+        configuration.waitsForConnectivity = true
+        configuration.timeoutIntervalForResource = 30
+        let session = URLSession(configuration: configuration, delegate: NoPairingRedirect(), delegateQueue: nil)
+        defer { session.invalidateAndCancel() }
+        let (data, response) = try await session.data(for: request)
+        guard let http = response as? HTTPURLResponse else { throw LocalPairingError.unavailable }
+        return (data, http)
+    }
+
+    private struct Claim: Encodable { let kind: String; let code: String }
+    private struct Reply: Decodable { let url: String }
+}
+
+private final class NoPairingRedirect: NSObject, URLSessionTaskDelegate {
+    func urlSession(_ session: URLSession, task: URLSessionTask, willPerformHTTPRedirection response: HTTPURLResponse,
+                    newRequest request: URLRequest, completionHandler: @escaping @Sendable (URLRequest?) -> Void) {
+        completionHandler(nil)
+    }
+}
+
+public enum LocalPairingError: Error, HelpfulError, Equatable {
+    case address, code, password, unreachable, unavailable
+
+    public var help: String {
+        let english = switch self {
+        case .address: "Enter the box address shown beside the pairing code, for example ftw.local:8080."
+        case .code: "That code has expired, was used or is incorrect. Make a new pairing code in Settings → FTW app."
+        case .password: "Enter the house password you use in the box's dashboard."
+        case .unreachable: "Could not reach the box. Stay on your home Wi-Fi, check its address and allow Local Network access for FTW in iPhone Settings."
+        case .unavailable: "Could not pair with a code. Update the box, make a new code and try again, or use a picture of its QR."
+        }
+        return NodeWords.text(english)
+    }
+}

appleApp/FTWKit/Sources/FTWKit/Identity/PairingImage.swift

@@ -1,9 +1,8 @@
 import CoreImage
 import Foundation
 
-/// A pairing link read off a picture of the QR. The simulator has no camera,
-/// so this is how pairing is tried there. The link then takes the same path
-/// as one the camera read.
+/// A pairing link read from a picture or screenshot of the QR. It takes the
+/// same path as a camera scan, including on a phone with no second screen.
 public enum PairingImage {
     /// The first QR in the picture that `Enrollment` accepts, or nil.
     public static func link(in imageData: Data) -> String? {

appleApp/FTWKit/Sources/FTWKit/State/NodeWords.swift

@@ -277,6 +277,22 @@ public enum NodeWords {
         "Get this phone back in": "Få in telefonen igen",
         "Welcome back": "Välkommen tillbaka",
         "Connect FTW": "Anslut FTW",
+        "Can't see Show pairing code? Turn on Let the FTW app connect to this box, then choose Save and restart FTW in the dashboard.": "Ser du inte Show pairing code? Slå på Let the FTW app connect to this box och välj sedan Save and restart FTW i webbgränssnittet.",
+        "Enter pairing code": "Ange parkod",
+        "Connect": "Anslut",
+        "Stay on your home Wi-Fi.": "Anslut till hemmets wifi.",
+        "Box address": "Boxens adress",
+        "Pairing code": "Parkod",
+        "House password": "Huslösenord",
+        "Connecting to your box": "Ansluter till boxen",
+        "On this iPhone, open your box in Safari. In Settings → FTW app, choose Use a pairing code. Return here and enter it while on your home Wi-Fi.": "Öppna boxen i Safari på denna iPhone. Välj Use a pairing code under Settings → FTW app. Gå tillbaka hit och ange koden medan du är på hemmets wifi.",
+        "Copying the code in Safari includes the box address. You can also paste a full pairing link here.": "När du kopierar koden i Safari följer boxens adress med. Du kan också klistra in en hel parkopplingslänk här.",
+        "Have only this iPhone? Open the box in Safari, then Settings → FTW app. Open the pairing link in FTW or use a pairing code.": "Har du bara denna iPhone? Öppna boxen i Safari och välj Settings → FTW app. Öppna parkopplingslänken i FTW eller använd en parkod.",
+        "Enter the box address shown beside the pairing code, for example ftw.local:8080.": "Ange boxens adress som står vid parkoden, till exempel ftw.local:8080.",
+        "That code has expired, was used or is incorrect. Make a new pairing code in Settings → FTW app.": "Koden har gått ut, har använts eller stämmer inte. Skapa en ny parkod under Settings → FTW app.",
+        "Enter the house password you use in the box's dashboard.": "Ange det huslösenord du använder i boxens webbgränssnitt.",
+        "Could not reach the box. Stay on your home Wi-Fi, check its address and allow Local Network access for FTW in iPhone Settings.": "Kunde inte nå boxen. Anslut till hemmets wifi, kontrollera adressen och tillåt Lokalt nätverk för FTW i iPhones inställningar.",
+        "Could not pair with a code. Update the box, make a new code and try again, or use a picture of its QR.": "Kunde inte parkoppla med kod. Uppdatera boxen, skapa en ny kod och försök igen, eller använd en bild av QR-koden.",
         "In your box's local dashboard, open Settings → FTW app. Hold the pairing QR inside the frame.": "Öppna Settings → FTW app i boxens lokala dashboard. Håll QR-koden inom ramen.",
         "Confirm with Face ID or Touch ID if your phone asks.": "Bekräfta med Face ID eller Touch ID om telefonen frågar.",
         "Loading a simulated home.": "Laddar ett simulerat hem.",