Add history and settings to watch app

Sesame-Watch Watch App/Assets.xcassets/AccentColor.colorset/Contents.json

@@ -0,0 +1,11 @@
+{
+  "colors" : [
+    {
+      "idiom" : "universal"
+    }
+  ],
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}

Sesame-Watch Watch App/Assets.xcassets/AppIcon.appiconset/Contents.json

@@ -0,0 +1,14 @@
+{
+  "images" : [
+    {
+      "filename" : "sesame.png",
+      "idiom" : "universal",
+      "platform" : "watchos",
+      "size" : "1024x1024"
+    }
+  ],
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}

Sesame-Watch Watch App/Assets.xcassets/Contents.json

@@ -0,0 +1,6 @@
+{
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}

Sesame-Watch Watch App/ContentView.swift

@@ -0,0 +1,134 @@
+import SwiftUI
+import SFSafeSymbols
+import CryptoKit
+
+struct ContentView: View {
+    
+    @AppStorage("server")
+    var serverPath: String = "https://christophhagen.de/sesame/"
+    
+    @AppStorage("localIP")
+    var localAddress: String = "192.168.178.104/"
+
+    @AppStorage("counter")
+    var nextMessageCounter: Int = 0
+
+    @AppStorage("compensate")
+    var isCompensatingDaylightTime: Bool = false
+    
+    @AppStorage("local")
+    private var useLocalConnection = false
+    
+    @AppStorage("deviceId")
+    private var deviceId: Int = 0
+    
+    @EnvironmentObject
+    var keyManager: KeyManagement
+    
+    @State
+    var state: ClientState = .noKeyAvailable
+    
+    let server = Client()
+
+    let history = HistoryManager()
+
+    var buttonBackground: Color {
+        state.allowsAction ?
+            .white.opacity(0.2) :
+            .black.opacity(0.2)
+    }
+
+    var buttonColor: Color {
+        state.allowsAction ? .white : .gray
+    }
+    
+    var body: some View {
+        HStack {
+            Spacer()
+            VStack(alignment: .center) {
+                Image(systemSymbol: .lock)
+                    .resizable()
+                    .aspectRatio(contentMode: .fit)
+                    .fontWeight(.ultraLight)
+                    .padding()
+                    .onTapGesture(perform: mainButtonPressed)
+                    .disabled(!state.allowsAction)
+                Text(state.actionText)
+                    .font(.subheadline)
+            }
+            Spacer()
+        }
+        .background(state.color)
+        .animation(.easeInOut, value: state.color)
+        .onAppear {
+            if keyManager.hasAllKeys, state == .noKeyAvailable {
+                state = .ready
+            }
+        }
+    }
+    
+    func mainButtonPressed() {
+        guard let key = keyManager.get(.remoteKey),
+              let token = keyManager.get(.authToken)?.data,
+              let deviceId = UInt8(exactly: deviceId) else {
+            return
+        }
+        let count = UInt32(nextMessageCounter)
+        let sentTime = Date()
+        // Add time to compensate that the device is using daylight savings time
+        let timeCompensation: UInt32 = isCompensatingDaylightTime ? 3600 : 0
+        let content = Message.Content(
+            time: sentTime.timestamp + timeCompensation,
+            id: count,
+            device: deviceId)
+        let message = content.authenticate(using: key)
+        let historyItem = HistoryItem(sent: message.content, date: sentTime, local: useLocalConnection)
+        state = .waitingForResponse
+        print("Sending message \(count)")
+        Task {
+            let (newState, responseMessage) = await send(message, authToken: token)
+            let receivedTime = Date.now
+            //responseTime = receivedTime
+            state = newState
+            let finishedItem = historyItem.didReceive(response: newState, date: receivedTime, message: responseMessage?.content)
+            guard let key = keyManager.get(.deviceKey) else {
+                save(historyItem: finishedItem.notAuthenticated())
+                return
+            }
+            guard let responseMessage else {
+                save(historyItem: finishedItem)
+                return
+            }
+            guard responseMessage.isValid(using: key) else {
+                save(historyItem: finishedItem.invalidated())
+                return
+            }
+            
+            nextMessageCounter = Int(responseMessage.content.id)
+            save(historyItem: finishedItem)
+        }
+    }
+    
+    private func send(_ message: Message, authToken: Data) async -> (state: ClientState, response: Message?) {
+        if useLocalConnection {
+            return await server.sendMessageOverLocalNetwork(message, server: localAddress)
+        } else {
+            return await server.send(message, server: serverPath, authToken: authToken)
+        }
+    }
+    
+    private func save(historyItem: HistoryItem) {
+        do {
+            try history.save(item: historyItem)
+        } catch {
+            print("Failed to save item: \(error)")
+        }
+    }
+}
+
+struct ContentView_Previews: PreviewProvider {
+    static var previews: some View {
+        ContentView()
+            .environmentObject(KeyManagement())
+    }
+}

Sesame-Watch Watch App/Date+Extensions.swift

@@ -0,0 +1,12 @@
+import Foundation
+
+extension Date {
+
+    var timestamp: UInt32 {
+        UInt32(timeIntervalSince1970.rounded())
+    }
+
+    init(timestamp: UInt32) {
+        self.init(timeIntervalSince1970: TimeInterval(timestamp))
+    }
+}

Sesame-Watch Watch App/HistoryItemDetail.swift

@@ -0,0 +1,67 @@
+import SwiftUI
+import SFSafeSymbols
+
+private let df: DateFormatter = {
+    let df = DateFormatter()
+    df.dateStyle = .short
+    df.timeStyle = .short
+    df.doesRelativeDateFormatting = true
+    return df
+}()
+
+struct HistoryItemDetail: View {
+
+    let item: HistoryItem
+    
+    private var entryTime: String {
+        df.string(from: item.requestDate)
+    }
+
+    var counterText: String {
+        let sentCounter = item.request.id
+        let startText = "\(sentCounter)"
+        guard let rCounter = item.responseMessage?.id else {
+            return startText
+        }
+        guard sentCounter + 1 != rCounter && sentCounter != rCounter else {
+            return startText
+        }
+        return "\(sentCounter) -> \(rCounter)"
+    }
+
+    var body: some View {
+        List {
+            SettingsListTextItem(
+                title: "Status",
+                value: item.response?.description ?? "No response")
+            SettingsListTextItem(
+                title: "Date",
+                value: entryTime)
+            SettingsListTextItem(
+                title: "Connection",
+                value: item.usedLocalConnection ? "Local" : "Remote")
+            SettingsListTextItem(
+                title: "Device ID",
+                value: "\(item.request.deviceId!)")
+            SettingsListTextItem(
+                title: "Message Counter",
+                value: counterText)
+            if let time = item.roundTripTime {
+                SettingsListTextItem(
+                    title: "Round Trip Time",
+                    value: "\(Int(time * 1000)) ms")
+            }
+            if let offset = item.clockOffset {
+                SettingsListTextItem(
+                    title: "Clock offset",
+                    value: "\(offset) seconds")
+            }
+        }.navigationTitle("Details")
+    }
+}
+
+struct HistoryItemDetail_Previews: PreviewProvider {
+    static var previews: some View {
+        HistoryItemDetail(item: .mock)
+    }
+}

Sesame-Watch Watch App/HistoryListRow.swift

@@ -0,0 +1,41 @@
+import SwiftUI
+import SFSafeSymbols
+
+private let df: DateFormatter = {
+    let df = DateFormatter()
+    df.dateStyle = .short
+    df.timeStyle = .short
+    df.doesRelativeDateFormatting = true
+    return df
+}()
+
+struct HistoryListRow: View {
+
+    let item: HistoryItem
+
+    private var entryTime: String {
+        df.string(from: item.requestDate)
+    }
+
+    var body: some View {
+        VStack(alignment: .leading) {
+            HStack {
+                Image(systemSymbol: item.response?.symbol ?? .exclamationmarkTriangle)
+                Text(item.response?.description ?? "No response")
+                    .font(.headline)
+                    .foregroundColor(.primary)
+            }
+            Text(entryTime)
+                .font(.footnote)
+                .foregroundColor(.accentColor)
+
+        }
+
+    }
+}
+
+struct HistoryListRow_Previews: PreviewProvider {
+    static var previews: some View {
+        HistoryListRow(item: .mock)
+    }
+}

Sesame-Watch Watch App/HistoryView.swift

@@ -0,0 +1,37 @@
+import SwiftUI
+
+struct HistoryView: View {
+
+    let history: HistoryManagerProtocol
+
+    @State
+    private var items: [HistoryItem] = []
+
+    var body: some View {
+        NavigationStack {
+            List(items) { item in
+                NavigationLink {
+                    HistoryItemDetail(item: item)
+                } label: {
+                    HistoryListRow(item: item)
+                }
+            }
+            .navigationTitle("History")
+        }.onAppear(perform: loadItems)
+    }
+
+    private func loadItems() {
+        Task {
+            let entries = history.loadEntries()
+            DispatchQueue.main.async {
+                items = entries
+            }
+        }
+    }
+}
+
+struct HistoryView_Previews: PreviewProvider {
+    static var previews: some View {
+        HistoryView(history: HistoryManagerMock())
+    }
+}

Sesame-Watch Watch App/Preview Content/Preview Assets.xcassets/Contents.json

@@ -0,0 +1,6 @@
+{
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}

Sesame-Watch Watch App/Sesame_WatchApp.swift

@@ -0,0 +1,20 @@
+import SwiftUI
+
+@main
+struct Sesame_Watch_Watch_AppApp: App {
+    
+    let keyManagement = KeyManagement()
+    
+    var body: some Scene {
+        WindowGroup {
+            TabView {
+                ContentView()
+                    .environmentObject(keyManagement)
+                SettingsView()
+                    .environmentObject(keyManagement)
+                HistoryView(history: HistoryManager())
+            }
+            .tabViewStyle(PageTabViewStyle())
+        }
+    }
+}

Sesame-Watch Watch App/Settings/SettingsKeyInputView.swift

@@ -0,0 +1,77 @@
+import SwiftUI
+import CryptoKit
+
+struct SettingsKeyInputView: View {
+
+    let type: KeyManagement.KeyType
+
+    @State
+    private var text: String = ""
+
+    let footnote: String
+
+    @EnvironmentObject
+    private var keys: KeyManagement
+
+    private var hasKey: Bool {
+        keys.has(type)
+    }
+
+    private var displayText: String {
+        keys.get(type)?.displayString ?? "-"
+    }
+
+    private var copyText: String {
+        guard let key = keys.get(type)?.data else {
+            return ""
+        }
+        guard type.usesHashing else {
+            return key.hexEncoded
+        }
+        return SHA256.hash(data: key).hexEncoded
+    }
+
+    var body: some View {
+        ScrollView {
+            VStack(alignment: .leading) {
+                TextField(type.displayName, text: $text)
+                    .onSubmit(validateText)
+                    .foregroundColor(.accentColor)
+                Text(footnote)
+                    .font(.footnote)
+                    .foregroundColor(.secondary)
+            }
+            .navigationTitle(type.displayName)
+            .onAppear {
+                if text == "" {
+                    text = displayText
+                    print("Text inserted")
+                }
+            }
+        }
+    }
+
+    private func validateText() {
+        let cleanText = text.replacingOccurrences(of: " ", with: "").trimmingCharacters(in: .whitespacesAndNewlines).lowercased()
+        guard let keyData = Data(fromHexEncodedString: cleanText) else {
+            print("Invalid key string")
+            return
+        }
+        let keyLength = type.keyLength.bitCount
+        guard keyData.count * 8 == keyLength else {
+            print("Invalid key length \(keyData.count * 8) bits, expected \(keyLength) (Input: '\(text)')")
+            return
+        }
+        keys.save(type, data: keyData)
+        print("Key \(type) saved")
+    }
+}
+
+struct SettingsKeyInputView_Previews: PreviewProvider {
+    static var previews: some View {
+        SettingsKeyInputView(
+            type: .remoteKey,
+            footnote: "Some text describing the purpose of the key.")
+        .environmentObject(KeyManagement())
+    }
+}

Sesame-Watch Watch App/Settings/SettingsKeyItemLink.swift

@@ -0,0 +1,47 @@
+import SwiftUI
+
+struct SettingsKeyItemLink: View {
+
+    let type: KeyManagement.KeyType
+
+    let footnote: String
+
+    @EnvironmentObject
+    private var keys: KeyManagement
+
+    @State
+    private var keyText = "..."
+
+    var body: some View {
+        NavigationLink {
+            SettingsKeyInputView(
+                type: type,
+                footnote: footnote)
+            .environmentObject(keys)
+        } label: {
+            SettingsListTextItem(
+                title: type.displayName,
+                value: keyText)
+            .onAppear(perform: updateKeyText)
+        }
+        .buttonStyle(PlainButtonStyle())
+    }
+
+    private func updateKeyText() {
+        Task {
+            let key = keys.get(type)?.displayString ?? "Not set"
+            DispatchQueue.main.async {
+                keyText = key
+            }
+        }
+    }
+}
+
+struct SettingsKeyItemLink_Previews: PreviewProvider {
+    static var previews: some View {
+        SettingsKeyItemLink(
+            type: .deviceKey,
+            footnote: "Some text describing the purpose of the key.")
+        .environmentObject(KeyManagement())
+    }
+}

Sesame-Watch Watch App/Settings/SettingsListTextItem.swift

@@ -0,0 +1,31 @@
+import SwiftUI
+
+struct SettingsListTextItem: View {
+
+    let title: String
+
+    let value: String
+
+    var body: some View {
+        VStack(alignment: .leading) {
+            HStack {
+                Text(title)
+                    .foregroundColor(.primary)
+                Spacer()
+            }
+            Text(value)
+                .font(.footnote)
+                .foregroundColor(.secondary)
+                .lineLimit(1)
+        }
+        .padding()
+    }
+}
+
+struct SettingsListTextItem_Previews: PreviewProvider {
+    static var previews: some View {
+        SettingsListTextItem(
+            title: "Title",
+            value: "Some longer text")
+    }
+}

Sesame-Watch Watch App/Settings/SettingsListToggleItem.swift

@@ -0,0 +1,28 @@
+import SwiftUI
+
+struct SettingsListToggleItem: View {
+
+    let title: String
+
+    @Binding
+    var value: Bool
+
+    let subtitle: String
+
+    var body: some View {
+        VStack(alignment: .leading) {
+            Toggle(title, isOn: $value)
+            Text(subtitle)
+                .font(.footnote)
+                .foregroundColor(.secondary)
+        }
+        .padding()
+        .cornerRadius(8)
+    }
+}
+
+struct SettingsListToggleItem_Previews: PreviewProvider {
+    static var previews: some View {
+        SettingsListToggleItem(title: "Toggle", value: .constant(true), subtitle: "Some longer text explaining what the toggle does")
+    }
+}

Sesame-Watch Watch App/Settings/SettingsNumberInputView.swift

@@ -0,0 +1,45 @@
+import SwiftUI
+
+struct SettingsNumberInputView: View {
+
+    let title: String
+
+    @Binding
+    var value: Int
+
+    @State
+    private var text: String = ""
+
+    let footnote: String
+
+    var body: some View {
+        VStack(alignment: .leading) {
+            TextField(title, text: $text)
+                .onSubmit {
+                    guard let newValue = Int(text) else {
+                        return
+                    }
+                    value = newValue
+                }
+                .foregroundColor(.accentColor)
+            Text(footnote)
+                .font(.footnote)
+                .foregroundColor(.secondary)
+            Spacer()
+        }
+        .navigationTitle(title)
+        .navigationBarBackButtonHidden(false)
+        .onAppear {
+            text = "\(value)"
+        }
+    }
+}
+
+struct SettingsNumberInputView_Previews: PreviewProvider {
+    static var previews: some View {
+        SettingsNumberInputView(
+            title: "Title",
+            value: .constant(0),
+            footnote: "Some more text explaining the purpose of the text field.")
+    }
+}

Sesame-Watch Watch App/Settings/SettingsNumberItemLink.swift

@@ -0,0 +1,30 @@
+import SwiftUI
+
+struct SettingsNumberItemLink: View {
+
+    let title: String
+
+    @Binding
+    var value: Int
+
+    let footnote: String
+
+    var body: some View {
+        NavigationLink {
+            SettingsNumberInputView(
+                title: title,
+                value: $value,
+                footnote: footnote
+            )
+        } label: {
+            SettingsListTextItem(title: title, value: "\(value)")
+        }
+        .buttonStyle(PlainButtonStyle())
+    }
+}
+
+struct SettingsNumberItemLink_Previews: PreviewProvider {
+    static var previews: some View {
+        SettingsNumberItemLink(title: "Title", value: .constant(0), footnote: "Some more text explaining the purpose of the text field.")
+    }
+}

Sesame-Watch Watch App/Settings/SettingsTextInputView.swift

@@ -0,0 +1,33 @@
+import SwiftUI
+
+struct SettingsTextInputView: View {
+
+    let title: String
+
+    @Binding
+    var text: String
+
+    let footnote: String
+
+    var body: some View {
+        VStack(alignment: .leading) {
+            TextField(title, text: $text)
+                .foregroundColor(.accentColor)
+            Text(footnote)
+                .font(.footnote)
+                .foregroundColor(.secondary)
+            Spacer()
+        }
+        .navigationTitle(title)
+        .navigationBarBackButtonHidden(false)
+    }
+}
+
+struct SettingsTextInputView_Previews: PreviewProvider {
+    static var previews: some View {
+        SettingsTextInputView(
+            title: "Title",
+            text: .constant("Text"),
+            footnote: "Some more text explaining the purpose of the text field.")
+    }
+}

Sesame-Watch Watch App/Settings/SettingsTextItemLink.swift

@@ -0,0 +1,30 @@
+import SwiftUI
+
+struct SettingsTextItemLink: View {
+
+    let title: String
+
+    @Binding
+    var value: String
+
+    let footnote: String
+
+    var body: some View {
+        NavigationLink {
+            SettingsTextInputView(
+                title: title,
+                text: $value,
+                footnote: footnote
+            )
+        } label: {
+            SettingsListTextItem(title: title, value: value)
+        }
+        .buttonStyle(PlainButtonStyle())
+    }
+}
+
+struct SettingsTextItemLink_Previews: PreviewProvider {
+    static var previews: some View {
+        SettingsTextItemLink(title: "Title", value: .constant("Some value"), footnote: "Some more text explaining the purpose of the text field.")
+    }
+}

Sesame-Watch Watch App/SettingsView.swift

@@ -0,0 +1,77 @@
+import SwiftUI
+
+struct SettingsView: View {
+
+    @AppStorage("server")
+    var serverPath: String = "https://christophhagen.de/sesame/"
+
+    @AppStorage("localIP")
+    var localAddress: String = "192.168.178.104/"
+
+    @AppStorage("counter")
+    var nextMessageCounter: Int = 0
+
+    @AppStorage("compensate")
+    var isCompensatingDaylightTime: Bool = false
+
+    @AppStorage("local")
+    private var useLocalConnection = false
+
+    @AppStorage("deviceId")
+    private var deviceId: Int = 0
+
+    @EnvironmentObject
+    var keys: KeyManagement
+
+    var body: some View {
+        NavigationStack {
+            List {
+                SettingsTextItemLink(
+                    title: "Server url",
+                    value: $serverPath,
+                    footnote: "The url where the sesame server listens for incoming messages.")
+                SettingsTextItemLink(
+                    title: "Local url",
+                    value: $localAddress,
+                    footnote: "The url where the device can be reached directly on the local WiFi network.")
+                SettingsListToggleItem(
+                    title: "Local connection",
+                    value: $useLocalConnection,
+                    subtitle: "Attempt to communicate directly with the device, which requires a WiFi connection on the same network.")
+                SettingsNumberItemLink(
+                    title: "Device ID",
+                    value: $deviceId,
+                    footnote: "The device ID is unique for each remote device, and is assigned by the system administrator.")
+                SettingsNumberItemLink(
+                    title: "Message counter",
+                    value: $nextMessageCounter,
+                    footnote: "The message counter is increased after every message to the device, and used to prevent replay attacks.")
+                SettingsListToggleItem(
+                    title: "Daylight savings",
+                    value: $isCompensatingDaylightTime,
+                    subtitle: "Compensate timestamps if the remote has daylight savings time wrongly set.")
+                SettingsKeyItemLink(
+                    type: .deviceKey,
+                    footnote: "Some text describing the purpose of the key.")
+                .environmentObject(keys)
+                SettingsKeyItemLink(
+                    type: .remoteKey,
+                    footnote: "Some text describing the purpose of the key.")
+                .environmentObject(keys)
+                SettingsKeyItemLink(
+                    type: .authToken,
+                    footnote: "Some text describing the purpose of the key.")
+                .environmentObject(keys)
+            }
+            .navigationTitle("Settings")
+        }
+    }
+}
+
+struct SettingsView_Previews: PreviewProvider {
+    static var previews: some View {
+        SettingsView()
+            .previewDevice("Apple Watch Series 7 - 41mm")
+            .environmentObject(KeyManagement())
+    }
+}

Sesame.xcodeproj/project.pbxproj

@@ -14,13 +14,47 @@
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-		884A45CD27A465F500D6E650 /* Client.swift in Sources */ = {isa = PBXBuildFile; fileRef = 884A45CC27A465F500D6E650 /* Client.swift */; };
 		884A45CF27A5402D00D6E650 /* MessageResult.swift in Sources */ = {isa = PBXBuildFile; fileRef = 884A45CE27A5402D00D6E650 /* MessageResult.swift */; };
+		8864664F29E5684C004FE2BE /* CBORCoding in Frameworks */ = {isa = PBXBuildFile; productRef = 8864664E29E5684C004FE2BE /* CBORCoding */; };
+		8864665229E5939C004FE2BE /* SFSafeSymbols in Frameworks */ = {isa = PBXBuildFile; productRef = 8864665129E5939C004FE2BE /* SFSafeSymbols */; };
+		888362342A80F3F90032BBB2 /* SettingsView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 888362332A80F3F90032BBB2 /* SettingsView.swift */; };
+		888362362A80F4420032BBB2 /* HistoryView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 888362352A80F4420032BBB2 /* HistoryView.swift */; };
+		88E197B229EDC9BC00BF1D19 /* Sesame_WatchApp.swift in Sources */ = {isa = PBXBuildFile; fileRef = 88E197B129EDC9BC00BF1D19 /* Sesame_WatchApp.swift */; };
+		88E197B429EDC9BC00BF1D19 /* ContentView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 88E197B329EDC9BC00BF1D19 /* ContentView.swift */; };
+		88E197B629EDC9BD00BF1D19 /* Assets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = 88E197B529EDC9BD00BF1D19 /* Assets.xcassets */; };
+		88E197B929EDC9BD00BF1D19 /* Preview Assets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = 88E197B829EDC9BD00BF1D19 /* Preview Assets.xcassets */; };
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+		88E197C729EDCCBD00BF1D19 /* Client.swift in Sources */ = {isa = PBXBuildFile; fileRef = 884A45CC27A465F500D6E650 /* Client.swift */; };
+		88E197C829EDCCCE00BF1D19 /* ClientState.swift in Sources */ = {isa = PBXBuildFile; fileRef = 884A45C827A43D7900D6E650 /* ClientState.swift */; };
+		88E197C929EDCCE100BF1D19 /* Message.swift in Sources */ = {isa = PBXBuildFile; fileRef = E24EE77827FF95E00011CFD2 /* Message.swift */; };
+		88E197CC29EDCD4900BF1D19 /* NIOCore in Frameworks */ = {isa = PBXBuildFile; productRef = 88E197CB29EDCD4900BF1D19 /* NIOCore */; };
+		88E197CE29EDCD7500BF1D19 /* CBORCoding in Frameworks */ = {isa = PBXBuildFile; productRef = 88E197CD29EDCD7500BF1D19 /* CBORCoding */; };
+		88E197D029EDCD7D00BF1D19 /* SFSafeSymbols in Frameworks */ = {isa = PBXBuildFile; productRef = 88E197CF29EDCD7D00BF1D19 /* SFSafeSymbols */; };
+		88E197D129EDCE5F00BF1D19 /* Data+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = E24EE77127FDCCC00011CFD2 /* Data+Extensions.swift */; };
+		88E197D229EDCE6600BF1D19 /* RouteAPI.swift in Sources */ = {isa = PBXBuildFile; fileRef = E2C5C1DA2806FE8900769EF6 /* RouteAPI.swift */; };
+		88E197D329EDCE6E00BF1D19 /* MessageResult.swift in Sources */ = {isa = PBXBuildFile; fileRef = 884A45CE27A5402D00D6E650 /* MessageResult.swift */; };
+		88E197D429EDCE7600BF1D19 /* UInt32+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = E2C5C1DC281B3AC400769EF6 /* UInt32+Extensions.swift */; };
+		88E197D529EDCE8800BF1D19 /* ServerMessage.swift in Sources */ = {isa = PBXBuildFile; fileRef = E2C5C1F7281E769F00769EF6 /* ServerMessage.swift */; };
+		88E197D729EDCFE800BF1D19 /* Date+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = 88E197D629EDCFE800BF1D19 /* Date+Extensions.swift */; };
+		88E197D829EDD13B00BF1D19 /* SymmetricKey+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = 884A45CA27A464C000D6E650 /* SymmetricKey+Extensions.swift */; };
+		88E197D929EDD14D00BF1D19 /* HistoryItem.swift in Sources */ = {isa = PBXBuildFile; fileRef = E28DED34281EB17600259690 /* HistoryItem.swift */; };
+		E240654B2A8153C6009C1AD8 /* SettingsListTextItem.swift in Sources */ = {isa = PBXBuildFile; fileRef = E240654A2A8153C6009C1AD8 /* SettingsListTextItem.swift */; };
+		E240654D2A8155A3009C1AD8 /* SettingsListToggleItem.swift in Sources */ = {isa = PBXBuildFile; fileRef = E240654C2A8155A3009C1AD8 /* SettingsListToggleItem.swift */; };
+		E240654F2A8159B7009C1AD8 /* SettingsTextInputView.swift in Sources */ = {isa = PBXBuildFile; fileRef = E240654E2A8159B7009C1AD8 /* SettingsTextInputView.swift */; };
+		E24065512A819066009C1AD8 /* SettingsTextItemLink.swift in Sources */ = {isa = PBXBuildFile; fileRef = E24065502A819066009C1AD8 /* SettingsTextItemLink.swift */; };
+		E24065532A819614009C1AD8 /* SettingsNumberItemLink.swift in Sources */ = {isa = PBXBuildFile; fileRef = E24065522A819614009C1AD8 /* SettingsNumberItemLink.swift */; };
+		E24065552A819663009C1AD8 /* SettingsNumberInputView.swift in Sources */ = {isa = PBXBuildFile; fileRef = E24065542A819663009C1AD8 /* SettingsNumberInputView.swift */; };
+		E24065582A819AE3009C1AD8 /* SettingsKeyItemLink.swift in Sources */ = {isa = PBXBuildFile; fileRef = E24065572A819AE3009C1AD8 /* SettingsKeyItemLink.swift */; };
+		E240655A2A82218D009C1AD8 /* SettingsKeyInputView.swift in Sources */ = {isa = PBXBuildFile; fileRef = E24065592A82218D009C1AD8 /* SettingsKeyInputView.swift */; };
+		E240655B2A822397009C1AD8 /* KeyManagement.swift in Sources */ = {isa = PBXBuildFile; fileRef = 884A45C4279F4BBE00D6E650 /* KeyManagement.swift */; };
+		E240655C2A822C8E009C1AD8 /* HistoryManager.swift in Sources */ = {isa = PBXBuildFile; fileRef = E28DED36281EC7FB00259690 /* HistoryManager.swift */; };
+		E240655E2A822E97009C1AD8 /* HistoryListRow.swift in Sources */ = {isa = PBXBuildFile; fileRef = E240655D2A822E97009C1AD8 /* HistoryListRow.swift */; };
+		E24065602A822ED9009C1AD8 /* HistoryItemDetail.swift in Sources */ = {isa = PBXBuildFile; fileRef = E240655F2A822ED9009C1AD8 /* HistoryItemDetail.swift */; };
 		E24EE77227FDCCC00011CFD2 /* Data+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = E24EE77127FDCCC00011CFD2 /* Data+Extensions.swift */; };
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-		E28DED2D281E840B00259690 /* KeyView.swift in Sources */ = {isa = PBXBuildFile; fileRef = E28DED2C281E840B00259690 /* KeyView.swift */; };
+		E28DED2D281E840B00259690 /* SettingsView.swift in Sources */ = {isa = PBXBuildFile; fileRef = E28DED2C281E840B00259690 /* SettingsView.swift */; };
 		E28DED2F281E8A0500259690 /* SingleKeyView.swift in Sources */ = {isa = PBXBuildFile; fileRef = E28DED2E281E8A0500259690 /* SingleKeyView.swift */; };
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@@ -42,10 +76,28 @@
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 		884A45CE27A5402D00D6E650 /* MessageResult.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MessageResult.swift; sourceTree = "<group>"; };
+		888362332A80F3F90032BBB2 /* SettingsView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SettingsView.swift; sourceTree = "<group>"; };
+		888362352A80F4420032BBB2 /* HistoryView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = HistoryView.swift; sourceTree = "<group>"; };
+		88E197AC29EDC9BC00BF1D19 /* Sesame-Watch Watch App.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = "Sesame-Watch Watch App.app"; sourceTree = BUILT_PRODUCTS_DIR; };
+		88E197B129EDC9BC00BF1D19 /* Sesame_WatchApp.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Sesame_WatchApp.swift; sourceTree = "<group>"; };
+		88E197B329EDC9BC00BF1D19 /* ContentView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ContentView.swift; sourceTree = "<group>"; };
+		88E197B529EDC9BD00BF1D19 /* Assets.xcassets */ = {isa = PBXFileReference; lastKnownFileType = folder.assetcatalog; path = Assets.xcassets; sourceTree = "<group>"; };
+		88E197B829EDC9BD00BF1D19 /* Preview Assets.xcassets */ = {isa = PBXFileReference; lastKnownFileType = folder.assetcatalog; path = "Preview Assets.xcassets"; sourceTree = "<group>"; };
+		88E197D629EDCFE800BF1D19 /* Date+Extensions.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Date+Extensions.swift"; sourceTree = "<group>"; };
+		E240654A2A8153C6009C1AD8 /* SettingsListTextItem.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SettingsListTextItem.swift; sourceTree = "<group>"; };
+		E240654C2A8155A3009C1AD8 /* SettingsListToggleItem.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SettingsListToggleItem.swift; sourceTree = "<group>"; };
+		E240654E2A8159B7009C1AD8 /* SettingsTextInputView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SettingsTextInputView.swift; sourceTree = "<group>"; };
+		E24065502A819066009C1AD8 /* SettingsTextItemLink.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SettingsTextItemLink.swift; sourceTree = "<group>"; };
+		E24065522A819614009C1AD8 /* SettingsNumberItemLink.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SettingsNumberItemLink.swift; sourceTree = "<group>"; };
+		E24065542A819663009C1AD8 /* SettingsNumberInputView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SettingsNumberInputView.swift; sourceTree = "<group>"; };
+		E24065572A819AE3009C1AD8 /* SettingsKeyItemLink.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SettingsKeyItemLink.swift; sourceTree = "<group>"; };
+		E24065592A82218D009C1AD8 /* SettingsKeyInputView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SettingsKeyInputView.swift; sourceTree = "<group>"; };
+		E240655D2A822E97009C1AD8 /* HistoryListRow.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = HistoryListRow.swift; sourceTree = "<group>"; };
+		E240655F2A822ED9009C1AD8 /* HistoryItemDetail.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = HistoryItemDetail.swift; sourceTree = "<group>"; };
 		E24EE77127FDCCC00011CFD2 /* Data+Extensions.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Data+Extensions.swift"; sourceTree = "<group>"; };
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 		E24EE77827FF95E00011CFD2 /* Message.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Message.swift; sourceTree = "<group>"; };
-		E28DED2C281E840B00259690 /* KeyView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = KeyView.swift; sourceTree = "<group>"; };
+		E28DED2C281E840B00259690 /* SettingsView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SettingsView.swift; sourceTree = "<group>"; };
 		E28DED2E281E8A0500259690 /* SingleKeyView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SingleKeyView.swift; sourceTree = "<group>"; };
 		E28DED30281EAE9100259690 /* HistoryView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = HistoryView.swift; sourceTree = "<group>"; };
 		E28DED32281EB15B00259690 /* HistoryListItem.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = HistoryListItem.swift; sourceTree = "<group>"; };
@@ -62,10 +114,22 @@
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				8864665229E5939C004FE2BE /* SFSafeSymbols in Frameworks */,
+				8864664F29E5684C004FE2BE /* CBORCoding in Frameworks */,
 				E24EE77727FF95C00011CFD2 /* NIOCore in Frameworks */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
+		88E197A929EDC9BC00BF1D19 /* Frameworks */ = {
+			isa = PBXFrameworksBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+				88E197D029EDCD7D00BF1D19 /* SFSafeSymbols in Frameworks */,
+				88E197CE29EDCD7500BF1D19 /* CBORCoding in Frameworks */,
+				88E197CC29EDCD4900BF1D19 /* NIOCore in Frameworks */,
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
 /* End PBXFrameworksBuildPhase section */
 
 /* Begin PBXGroup section */
@@ -73,7 +137,9 @@
 			isa = PBXGroup;
 			children = (
 				884A45B5279F48C100D6E650 /* Sesame */,
+				88E197B029EDC9BC00BF1D19 /* Sesame-Watch Watch App */,
 				884A45B4279F48C100D6E650 /* Products */,
+				88E197CA29EDCD4900BF1D19 /* Frameworks */,
 			);
 			sourceTree = "<group>";
 		};
@@ -81,6 +147,7 @@
 			isa = PBXGroup;
 			children = (
 				884A45B3279F48C100D6E650 /* Sesame.app */,
+				88E197AC29EDC9BC00BF1D19 /* Sesame-Watch Watch App.app */,
 			);
 			name = Products;
 			sourceTree = "<group>";
@@ -96,10 +163,10 @@
 				E28DED32281EB15B00259690 /* HistoryListItem.swift */,
 				E28DED34281EB17600259690 /* HistoryItem.swift */,
 				E28DED36281EC7FB00259690 /* HistoryManager.swift */,
-				E28DED2C281E840B00259690 /* KeyView.swift */,
+				E28DED2C281E840B00259690 /* SettingsView.swift */,
 				E28DED2E281E8A0500259690 /* SingleKeyView.swift */,
-				884A45CC27A465F500D6E650 /* Client.swift */,
 				884A45C827A43D7900D6E650 /* ClientState.swift */,
+				884A45CC27A465F500D6E650 /* Client.swift */,
 				884A45C4279F4BBE00D6E650 /* KeyManagement.swift */,
 				884A45CA27A464C000D6E650 /* SymmetricKey+Extensions.swift */,
 				884A45BA279F48C300D6E650 /* Assets.xcassets */,
@@ -116,6 +183,53 @@
 			path = "Preview Content";
 			sourceTree = "<group>";
 		};
+		88E197B029EDC9BC00BF1D19 /* Sesame-Watch Watch App */ = {
+			isa = PBXGroup;
+			children = (
+				E24065562A819AAD009C1AD8 /* Settings */,
+				88E197B129EDC9BC00BF1D19 /* Sesame_WatchApp.swift */,
+				88E197B329EDC9BC00BF1D19 /* ContentView.swift */,
+				888362332A80F3F90032BBB2 /* SettingsView.swift */,
+				888362352A80F4420032BBB2 /* HistoryView.swift */,
+				E240655D2A822E97009C1AD8 /* HistoryListRow.swift */,
+				E240655F2A822ED9009C1AD8 /* HistoryItemDetail.swift */,
+				88E197B529EDC9BD00BF1D19 /* Assets.xcassets */,
+				88E197B729EDC9BD00BF1D19 /* Preview Content */,
+				88E197D629EDCFE800BF1D19 /* Date+Extensions.swift */,
+			);
+			path = "Sesame-Watch Watch App";
+			sourceTree = "<group>";
+		};
+		88E197B729EDC9BD00BF1D19 /* Preview Content */ = {
+			isa = PBXGroup;
+			children = (
+				88E197B829EDC9BD00BF1D19 /* Preview Assets.xcassets */,
+			);
+			path = "Preview Content";
+			sourceTree = "<group>";
+		};
+		88E197CA29EDCD4900BF1D19 /* Frameworks */ = {
+			isa = PBXGroup;
+			children = (
+			);
+			name = Frameworks;
+			sourceTree = "<group>";
+		};
+		E24065562A819AAD009C1AD8 /* Settings */ = {
+			isa = PBXGroup;
+			children = (
+				E24065502A819066009C1AD8 /* SettingsTextItemLink.swift */,
+				E24065522A819614009C1AD8 /* SettingsNumberItemLink.swift */,
+				E24065542A819663009C1AD8 /* SettingsNumberInputView.swift */,
+				E240654E2A8159B7009C1AD8 /* SettingsTextInputView.swift */,
+				E240654A2A8153C6009C1AD8 /* SettingsListTextItem.swift */,
+				E240654C2A8155A3009C1AD8 /* SettingsListToggleItem.swift */,
+				E24065572A819AE3009C1AD8 /* SettingsKeyItemLink.swift */,
+				E24065592A82218D009C1AD8 /* SettingsKeyInputView.swift */,
+			);
+			path = Settings;
+			sourceTree = "<group>";
+		};
 		E2C5C1D92806FE4A00769EF6 /* API */ = {
 			isa = PBXGroup;
 			children = (
@@ -148,11 +262,35 @@
 			name = Sesame;
 			packageProductDependencies = (
 				E24EE77627FF95C00011CFD2 /* NIOCore */,
+				8864664E29E5684C004FE2BE /* CBORCoding */,
+				8864665129E5939C004FE2BE /* SFSafeSymbols */,
 			);
 			productName = Sesame;
 			productReference = 884A45B3279F48C100D6E650 /* Sesame.app */;
 			productType = "com.apple.product-type.application";
 		};
+		88E197AB29EDC9BC00BF1D19 /* Sesame-Watch Watch App */ = {
+			isa = PBXNativeTarget;
+			buildConfigurationList = 88E197BF29EDC9BD00BF1D19 /* Build configuration list for PBXNativeTarget "Sesame-Watch Watch App" */;
+			buildPhases = (
+				88E197A829EDC9BC00BF1D19 /* Sources */,
+				88E197A929EDC9BC00BF1D19 /* Frameworks */,
+				88E197AA29EDC9BC00BF1D19 /* Resources */,
+			);
+			buildRules = (
+			);
+			dependencies = (
+			);
+			name = "Sesame-Watch Watch App";
+			packageProductDependencies = (
+				88E197CB29EDCD4900BF1D19 /* NIOCore */,
+				88E197CD29EDCD7500BF1D19 /* CBORCoding */,
+				88E197CF29EDCD7D00BF1D19 /* SFSafeSymbols */,
+			);
+			productName = "Sesame-Watch Watch App";
+			productReference = 88E197AC29EDC9BC00BF1D19 /* Sesame-Watch Watch App.app */;
+			productType = "com.apple.product-type.application";
+		};
 /* End PBXNativeTarget section */
 
 /* Begin PBXProject section */
@@ -160,11 +298,15 @@
 			isa = PBXProject;
 			attributes = {
 				BuildIndependentTargetsInParallel = 1;
-				LastSwiftUpdateCheck = 1320;
+				LastSwiftUpdateCheck = 1430;
 				LastUpgradeCheck = 1320;
 				TargetAttributes = {
 					884A45B2279F48C100D6E650 = {
 						CreatedOnToolsVersion = 13.2.1;
+						LastSwiftMigration = 1430;
+					};
+					88E197AB29EDC9BC00BF1D19 = {
+						CreatedOnToolsVersion = 14.3;
 					};
 				};
 			};
@@ -179,12 +321,15 @@
 			mainGroup = 884A45AA279F48C100D6E650;
 			packageReferences = (
 				E24EE77527FF95C00011CFD2 /* XCRemoteSwiftPackageReference "swift-nio" */,
+				8864664D29E5684C004FE2BE /* XCRemoteSwiftPackageReference "CBORCoding" */,
+				8864665029E5939C004FE2BE /* XCRemoteSwiftPackageReference "SFSafeSymbols" */,
 			);
 			productRefGroup = 884A45B4279F48C100D6E650 /* Products */;
 			projectDirPath = "";
 			projectRoot = "";
 			targets = (
 				884A45B2279F48C100D6E650 /* Sesame */,
+				88E197AB29EDC9BC00BF1D19 /* Sesame-Watch Watch App */,
 			);
 		};
 /* End PBXProject section */
@@ -199,6 +344,15 @@
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
+		88E197AA29EDC9BC00BF1D19 /* Resources */ = {
+			isa = PBXResourcesBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+				88E197B929EDC9BD00BF1D19 /* Preview Assets.xcassets in Resources */,
+				88E197B629EDC9BD00BF1D19 /* Assets.xcassets in Resources */,
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
 /* End PBXResourcesBuildPhase section */
 
 /* Begin PBXSourcesBuildPhase section */
@@ -212,7 +366,6 @@
 				E28DED37281EC7FB00259690 /* HistoryManager.swift in Sources */,
 				E2C5C1DB2806FE8900769EF6 /* RouteAPI.swift in Sources */,
 				E2C5C1DD281B3AC400769EF6 /* UInt32+Extensions.swift in Sources */,
-				884A45CD27A465F500D6E650 /* Client.swift in Sources */,
 				E24EE77227FDCCC00011CFD2 /* Data+Extensions.swift in Sources */,
 				E24EE77427FF95920011CFD2 /* DeviceResponse.swift in Sources */,
 				884A45CB27A464C000D6E650 /* SymmetricKey+Extensions.swift in Sources */,
@@ -221,13 +374,48 @@
 				E28DED35281EB17600259690 /* HistoryItem.swift in Sources */,
 				884A45C927A43D7900D6E650 /* ClientState.swift in Sources */,
 				E28DED33281EB15B00259690 /* HistoryListItem.swift in Sources */,
-				E28DED2D281E840B00259690 /* KeyView.swift in Sources */,
+				E28DED2D281E840B00259690 /* SettingsView.swift in Sources */,
 				884A45B7279F48C100D6E650 /* SesameApp.swift in Sources */,
+				88E197C429EDCC8900BF1D19 /* Client.swift in Sources */,
 				884A45C5279F4BBE00D6E650 /* KeyManagement.swift in Sources */,
 				E2C5C1F8281E769F00769EF6 /* ServerMessage.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
+		88E197A829EDC9BC00BF1D19 /* Sources */ = {
+			isa = PBXSourcesBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+				888362342A80F3F90032BBB2 /* SettingsView.swift in Sources */,
+				88E197B429EDC9BC00BF1D19 /* ContentView.swift in Sources */,
+				E24065532A819614009C1AD8 /* SettingsNumberItemLink.swift in Sources */,
+				888362362A80F4420032BBB2 /* HistoryView.swift in Sources */,
+				E240654F2A8159B7009C1AD8 /* SettingsTextInputView.swift in Sources */,
+				88E197D329EDCE6E00BF1D19 /* MessageResult.swift in Sources */,
+				88E197D529EDCE8800BF1D19 /* ServerMessage.swift in Sources */,
+				88E197D129EDCE5F00BF1D19 /* Data+Extensions.swift in Sources */,
+				E240655A2A82218D009C1AD8 /* SettingsKeyInputView.swift in Sources */,
+				88E197D229EDCE6600BF1D19 /* RouteAPI.swift in Sources */,
+				E24065512A819066009C1AD8 /* SettingsTextItemLink.swift in Sources */,
+				88E197D729EDCFE800BF1D19 /* Date+Extensions.swift in Sources */,
+				88E197C829EDCCCE00BF1D19 /* ClientState.swift in Sources */,
+				E24065602A822ED9009C1AD8 /* HistoryItemDetail.swift in Sources */,
+				88E197B229EDC9BC00BF1D19 /* Sesame_WatchApp.swift in Sources */,
+				E24065582A819AE3009C1AD8 /* SettingsKeyItemLink.swift in Sources */,
+				88E197C929EDCCE100BF1D19 /* Message.swift in Sources */,
+				88E197D929EDD14D00BF1D19 /* HistoryItem.swift in Sources */,
+				E240654B2A8153C6009C1AD8 /* SettingsListTextItem.swift in Sources */,
+				88E197C729EDCCBD00BF1D19 /* Client.swift in Sources */,
+				88E197D429EDCE7600BF1D19 /* UInt32+Extensions.swift in Sources */,
+				E240655B2A822397009C1AD8 /* KeyManagement.swift in Sources */,
+				E240654D2A8155A3009C1AD8 /* SettingsListToggleItem.swift in Sources */,
+				E24065552A819663009C1AD8 /* SettingsNumberInputView.swift in Sources */,
+				E240655E2A822E97009C1AD8 /* HistoryListRow.swift in Sources */,
+				88E197D829EDD13B00BF1D19 /* SymmetricKey+Extensions.swift in Sources */,
+				E240655C2A822C8E009C1AD8 /* HistoryManager.swift in Sources */,
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
 /* End PBXSourcesBuildPhase section */
 
 /* Begin XCBuildConfiguration section */
@@ -352,6 +540,7 @@
 			buildSettings = {
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ASSETCATALOG_COMPILER_GLOBAL_ACCENT_COLOR_NAME = AccentColor;
+				CLANG_ENABLE_MODULES = YES;
 				CODE_SIGN_STYLE = Automatic;
 				CURRENT_PROJECT_VERSION = 1;
 				DEVELOPMENT_ASSET_PATHS = "\"Sesame/Preview Content\"";
@@ -373,6 +562,8 @@
 				PRODUCT_BUNDLE_IDENTIFIER = de.christophhagen.Sesame;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_EMIT_LOC_STRINGS = YES;
+				SWIFT_OBJC_BRIDGING_HEADER = "";
+				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
 				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = 1;
 			};
@@ -383,6 +574,7 @@
 			buildSettings = {
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ASSETCATALOG_COMPILER_GLOBAL_ACCENT_COLOR_NAME = AccentColor;
+				CLANG_ENABLE_MODULES = YES;
 				CODE_SIGN_STYLE = Automatic;
 				CURRENT_PROJECT_VERSION = 1;
 				DEVELOPMENT_ASSET_PATHS = "\"Sesame/Preview Content\"";
@@ -404,11 +596,74 @@
 				PRODUCT_BUNDLE_IDENTIFIER = de.christophhagen.Sesame;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SWIFT_EMIT_LOC_STRINGS = YES;
+				SWIFT_OBJC_BRIDGING_HEADER = "";
 				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = 1;
 			};
 			name = Release;
 		};
+		88E197BD29EDC9BD00BF1D19 /* Debug */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
+				ASSETCATALOG_COMPILER_GLOBAL_ACCENT_COLOR_NAME = AccentColor;
+				CLANG_CXX_LANGUAGE_STANDARD = "gnu++20";
+				CODE_SIGN_STYLE = Automatic;
+				CURRENT_PROJECT_VERSION = 1;
+				DEVELOPMENT_ASSET_PATHS = "\"Sesame-Watch Watch App/Preview Content\"";
+				DEVELOPMENT_TEAM = H8WR4M6QQ4;
+				ENABLE_PREVIEWS = YES;
+				GENERATE_INFOPLIST_FILE = YES;
+				INFOPLIST_KEY_CFBundleDisplayName = "Sesame-Watch";
+				INFOPLIST_KEY_UISupportedInterfaceOrientations = "UIInterfaceOrientationPortrait UIInterfaceOrientationPortraitUpsideDown";
+				INFOPLIST_KEY_WKWatchOnly = YES;
+				LD_RUNPATH_SEARCH_PATHS = (
+					"$(inherited)",
+					"@executable_path/Frameworks",
+				);
+				MARKETING_VERSION = 1.0;
+				PRODUCT_BUNDLE_IDENTIFIER = "de.christophhagen.Sesame-Watch.watchkitapp";
+				PRODUCT_NAME = "$(TARGET_NAME)";
+				SDKROOT = watchos;
+				SKIP_INSTALL = YES;
+				SWIFT_EMIT_LOC_STRINGS = YES;
+				SWIFT_VERSION = 5.0;
+				TARGETED_DEVICE_FAMILY = 4;
+				WATCHOS_DEPLOYMENT_TARGET = 9.4;
+			};
+			name = Debug;
+		};
+		88E197BE29EDC9BD00BF1D19 /* Release */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
+				ASSETCATALOG_COMPILER_GLOBAL_ACCENT_COLOR_NAME = AccentColor;
+				CLANG_CXX_LANGUAGE_STANDARD = "gnu++20";
+				CODE_SIGN_STYLE = Automatic;
+				CURRENT_PROJECT_VERSION = 1;
+				DEVELOPMENT_ASSET_PATHS = "\"Sesame-Watch Watch App/Preview Content\"";
+				DEVELOPMENT_TEAM = H8WR4M6QQ4;
+				ENABLE_PREVIEWS = YES;
+				GENERATE_INFOPLIST_FILE = YES;
+				INFOPLIST_KEY_CFBundleDisplayName = "Sesame-Watch";
+				INFOPLIST_KEY_UISupportedInterfaceOrientations = "UIInterfaceOrientationPortrait UIInterfaceOrientationPortraitUpsideDown";
+				INFOPLIST_KEY_WKWatchOnly = YES;
+				LD_RUNPATH_SEARCH_PATHS = (
+					"$(inherited)",
+					"@executable_path/Frameworks",
+				);
+				MARKETING_VERSION = 1.0;
+				PRODUCT_BUNDLE_IDENTIFIER = "de.christophhagen.Sesame-Watch.watchkitapp";
+				PRODUCT_NAME = "$(TARGET_NAME)";
+				SDKROOT = watchos;
+				SKIP_INSTALL = YES;
+				SWIFT_EMIT_LOC_STRINGS = YES;
+				SWIFT_VERSION = 5.0;
+				TARGETED_DEVICE_FAMILY = 4;
+				WATCHOS_DEPLOYMENT_TARGET = 9.4;
+			};
+			name = Release;
+		};
 /* End XCBuildConfiguration section */
 
 /* Begin XCConfigurationList section */
@@ -430,9 +685,34 @@
 			defaultConfigurationIsVisible = 0;
 			defaultConfigurationName = Release;
 		};
+		88E197BF29EDC9BD00BF1D19 /* Build configuration list for PBXNativeTarget "Sesame-Watch Watch App" */ = {
+			isa = XCConfigurationList;
+			buildConfigurations = (
+				88E197BD29EDC9BD00BF1D19 /* Debug */,
+				88E197BE29EDC9BD00BF1D19 /* Release */,
+			);
+			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
+		};
 /* End XCConfigurationList section */
 
 /* Begin XCRemoteSwiftPackageReference section */
+		8864664D29E5684C004FE2BE /* XCRemoteSwiftPackageReference "CBORCoding" */ = {
+			isa = XCRemoteSwiftPackageReference;
+			repositoryURL = "https://github.com/christophhagen/CBORCoding";
+			requirement = {
+				kind = upToNextMajorVersion;
+				minimumVersion = 1.0.0;
+			};
+		};
+		8864665029E5939C004FE2BE /* XCRemoteSwiftPackageReference "SFSafeSymbols" */ = {
+			isa = XCRemoteSwiftPackageReference;
+			repositoryURL = "https://github.com/SFSafeSymbols/SFSafeSymbols";
+			requirement = {
+				kind = upToNextMajorVersion;
+				minimumVersion = 4.0.0;
+			};
+		};
 		E24EE77527FF95C00011CFD2 /* XCRemoteSwiftPackageReference "swift-nio" */ = {
 			isa = XCRemoteSwiftPackageReference;
 			repositoryURL = "https://github.com/apple/swift-nio.git";
@@ -444,6 +724,31 @@
 /* End XCRemoteSwiftPackageReference section */
 
 /* Begin XCSwiftPackageProductDependency section */
+		8864664E29E5684C004FE2BE /* CBORCoding */ = {
+			isa = XCSwiftPackageProductDependency;
+			package = 8864664D29E5684C004FE2BE /* XCRemoteSwiftPackageReference "CBORCoding" */;
+			productName = CBORCoding;
+		};
+		8864665129E5939C004FE2BE /* SFSafeSymbols */ = {
+			isa = XCSwiftPackageProductDependency;
+			package = 8864665029E5939C004FE2BE /* XCRemoteSwiftPackageReference "SFSafeSymbols" */;
+			productName = SFSafeSymbols;
+		};
+		88E197CB29EDCD4900BF1D19 /* NIOCore */ = {
+			isa = XCSwiftPackageProductDependency;
+			package = E24EE77527FF95C00011CFD2 /* XCRemoteSwiftPackageReference "swift-nio" */;
+			productName = NIOCore;
+		};
+		88E197CD29EDCD7500BF1D19 /* CBORCoding */ = {
+			isa = XCSwiftPackageProductDependency;
+			package = 8864664D29E5684C004FE2BE /* XCRemoteSwiftPackageReference "CBORCoding" */;
+			productName = CBORCoding;
+		};
+		88E197CF29EDCD7D00BF1D19 /* SFSafeSymbols */ = {
+			isa = XCSwiftPackageProductDependency;
+			package = 8864665029E5939C004FE2BE /* XCRemoteSwiftPackageReference "SFSafeSymbols" */;
+			productName = SFSafeSymbols;
+		};
 		E24EE77627FF95C00011CFD2 /* NIOCore */ = {
 			isa = XCSwiftPackageProductDependency;
 			package = E24EE77527FF95C00011CFD2 /* XCRemoteSwiftPackageReference "swift-nio" */;

Sesame.xcodeproj/project.xcworkspace/xcshareddata/swiftpm/Package.resolved

@@ -1,5 +1,23 @@
 {
   "pins" : [
+    {
+      "identity" : "cborcoding",
+      "kind" : "remoteSourceControl",
+      "location" : "https://github.com/christophhagen/CBORCoding",
+      "state" : {
+        "revision" : "1e52c77523fca12cc290b17eed12fadb50ad72af",
+        "version" : "1.0.0"
+      }
+    },
+    {
+      "identity" : "sfsafesymbols",
+      "kind" : "remoteSourceControl",
+      "location" : "https://github.com/SFSafeSymbols/SFSafeSymbols",
+      "state" : {
+        "revision" : "7cca2d60925876b5953a2cf7341cd80fbeac983c",
+        "version" : "4.1.1"
+      }
+    },
     {
       "identity" : "swift-nio",
       "kind" : "remoteSourceControl",

Sesame.xcodeproj/xcuserdata/ch.xcuserdatad/xcschemes/xcschememanagement.plist

@@ -67,11 +67,16 @@
 			<key>orderHint</key>
 			<integer>0</integer>
 		</dict>
-		<key>Sesame.xcscheme_^#shared#^_</key>
+		<key>Sesame-Watch Watch App.xcscheme_^#shared#^_</key>
 		<dict>
 			<key>orderHint</key>
 			<integer>0</integer>
 		</dict>
+		<key>Sesame.xcscheme_^#shared#^_</key>
+		<dict>
+			<key>orderHint</key>
+			<integer>1</integer>
+		</dict>
 	</dict>
 </dict>
 </plist>

Sesame.xcodeproj/xcuserdata/imac.xcuserdatad/xcschemes/xcschememanagement.plist

@@ -4,11 +4,16 @@
 <dict>
 	<key>SchemeUserState</key>
 	<dict>
-		<key>Sesame.xcscheme_^#shared#^_</key>
+		<key>Sesame-Watch Watch App.xcscheme_^#shared#^_</key>
 		<dict>
 			<key>orderHint</key>
 			<integer>0</integer>
 		</dict>
+		<key>Sesame.xcscheme_^#shared#^_</key>
+		<dict>
+			<key>orderHint</key>
+			<integer>1</integer>
+		</dict>
 	</dict>
 </dict>
 </plist>

Sesame/API/DeviceResponse.swift

@@ -27,8 +27,8 @@ struct DeviceResponse {
     }
 
     /// Shorthand property for an invalid message.
-    static var invalidMessageData: DeviceResponse {
-        .init(event: .invalidMessageData)
+    static var invalidMessageSize: DeviceResponse {
+        .init(event: .invalidMessageSize)
     }
 
     /// Shorthand property for missing body data.
@@ -83,8 +83,8 @@ struct DeviceResponse {
     /// Get the reponse encoded in bytes.
     var encoded: Data {
         guard let message = response else {
-            return Data([event.rawValue])
+            return event.encoded
         }
-        return Data([event.rawValue]) + message.encoded
+        return event.encoded + message.encoded
     }
 }

Sesame/API/Message.swift

@@ -29,6 +29,14 @@ struct Message: Equatable, Hashable {
     }
 }
 
+extension Message: Codable {
+    
+    enum CodingKeys: Int, CodingKey {
+        case mac = 1
+        case content = 2
+    }
+}
+
 extension Message {
 
     /**
@@ -41,15 +49,18 @@ extension Message {
 
         /// The counter of the message (for freshness)
         let id: UInt32
+        
+        let deviceId: UInt8?
 
         /**
          Create new message content.
          - Parameter time: The time of message creation,
          - Parameter id: The counter of the message
          */
-        init(time: UInt32, id: UInt32) {
+        init(time: UInt32, id: UInt32, device: UInt8) {
             self.time = time
             self.id = id
+            self.deviceId = device
         }
 
         /**
@@ -61,20 +72,29 @@ extension Message {
          */
         init<T: Sequence>(decodeFrom data: T) where T.Element == UInt8 {
             self.time = UInt32(data: Data(data.prefix(MemoryLayout<UInt32>.size)))
-            self.id = UInt32(data: Data(data.dropFirst(MemoryLayout<UInt32>.size)))
+            self.id = UInt32(data: Data(data.dropLast().suffix(MemoryLayout<UInt32>.size)))
+            self.deviceId = data.suffix(1).last!
         }
 
         /// The byte length of an encoded message content
         static var length: Int {
-            MemoryLayout<UInt32>.size * 2
+            MemoryLayout<UInt32>.size * 2 + 1
         }
 
         /// The message content encoded to data
         var encoded: Data {
-            time.encoded + id.encoded
+            time.encoded + id.encoded + Data([deviceId ?? 0])
         }
     }
+}
 
+extension Message.Content: Codable {
+
+    enum CodingKeys: Int, CodingKey {
+        case time = 1
+        case id = 2
+        case deviceId = 3
+    }
 }
 
 extension Message {

Sesame/API/MessageResult.swift

@@ -11,8 +11,8 @@ enum MessageResult: UInt8 {
     /// A socket event on the device was unexpected (not binary data)
     case unexpectedSocketEvent = 2
 
-    /// The size of the payload (i.e. message) was invalid, or the data could not be read
-    case invalidMessageData = 3
+    /// The size of the payload (i.e. message) was invalid
+    case invalidMessageSize = 3
 
     /// The transmitted message could not be authenticated using the key
     case messageAuthenticationFailed = 4
@@ -25,6 +25,9 @@ enum MessageResult: UInt8 {
 
     /// The key was accepted by the device, and the door will be opened
     case messageAccepted = 7
+    
+    /// The device id is invalid
+    case messageDeviceInvalid = 8
 
 
     /// The request did not contain body data with the key
@@ -41,6 +44,10 @@ enum MessageResult: UInt8 {
 
     /// The device is connected
     case deviceConnected = 15
+
+    case invalidUrlParameter = 20
+
+    case invalidResponseAuthentication = 21
 }
 
 extension MessageResult: CustomStringConvertible {
@@ -51,7 +58,7 @@ extension MessageResult: CustomStringConvertible {
             return "The device received unexpected text"
         case .unexpectedSocketEvent:
             return "Unexpected socket event for the device"
-        case .invalidMessageData:
+        case .invalidMessageSize:
             return "Invalid message data"
         case .messageAuthenticationFailed:
             return "Message authentication failed"
@@ -61,6 +68,8 @@ extension MessageResult: CustomStringConvertible {
             return "Message counter invalid"
         case .messageAccepted:
             return "Message accepted"
+        case .messageDeviceInvalid:
+            return "Invalid device ID"
         case .noBodyData:
             return "No body data included in the request"
         case .deviceNotConnected:
@@ -71,6 +80,17 @@ extension MessageResult: CustomStringConvertible {
             return "Another operation is in progress"
         case .deviceConnected:
             return "The device is connected"
+        case .invalidUrlParameter:
+            return "The url parameter could not be found"
+        case .invalidResponseAuthentication:
+            return "The response could not be authenticated"
         }
     }
 }
+
+extension MessageResult {
+
+    var encoded: Data {
+        Data([rawValue])
+    }
+}

Sesame/API/ServerMessage.swift

@@ -11,8 +11,6 @@ struct ServerMessage {
 
     static let authTokenSize = SHA256.byteCount
 
-    static let length = authTokenSize + Message.length
-
     let authToken: Data
 
     let message: Message
@@ -21,31 +19,8 @@ struct ServerMessage {
         self.authToken = authToken
         self.message = message
     }
-    
-    /**
-     Decode a message from a byte buffer.
-     The buffer must contain at least `ServerMessage.length` bytes, or it will return `nil`.
-     - Parameter buffer: The buffer containing the bytes.
-     */
-    init?(decodeFrom buffer: ByteBuffer) {
-        guard let data = buffer.getBytes(at: 0, length: ServerMessage.length) else {
-            return nil
-        }
-        self.authToken = Data(data.prefix(ServerMessage.authTokenSize))
-        self.message = Message(decodeFrom: Data(data.dropFirst(ServerMessage.authTokenSize)))
-    }
 
     var encoded: Data {
         authToken + message.encoded
     }
-
-    static func token(from buffer: ByteBuffer) -> Data? {
-        guard buffer.readableBytes == authTokenSize else {
-            return nil
-        }
-        guard let bytes = buffer.getBytes(at: 0, length: authTokenSize) else {
-            return nil
-        }
-        return Data(bytes)
-    }
 }

Sesame/Client.swift

@@ -1,30 +1,50 @@
 import Foundation
 import CryptoKit
 
-struct Client {
-    
-    let server: URL
+final class Client {
     
+    // TODO: Use or delete
     private let delegate = NeverCacheDelegate()
     
-    init(server: URL) {
-        self.server = server
-    }
+    init() {}
 
-    func deviceStatus(authToken: Data) async -> ClientState {
-        await send(path: .getDeviceStatus, data: authToken).state
+    func deviceStatus(authToken: Data, server: String) async -> ClientState {
+        await send(path: .getDeviceStatus, server: server, data: authToken).state
     }
     
-    func send(_ message: Message, authToken: Data) async -> (state: ClientState, response: Message?) {
+    func sendMessageOverLocalNetwork(_ message: Message, server: String) async -> (state: ClientState, response: Message?) {
+        let data = message.encoded.hexEncoded
+        guard let url = URL(string: server + "message?m=\(data)") else {
+            return (.internalError("Invalid server url"), nil)
+        }
+        
+        var request = URLRequest(url: url)
+        request.httpMethod = "POST"
+        return await requestAndDecode(request)
+    }
+    
+    func send(_ message: Message, server: String, authToken: Data) async -> (state: ClientState, response: Message?) {
         let serverMessage = ServerMessage(authToken: authToken, message: message)
-        return await send(path: .postMessage, data: serverMessage.encoded)
+        return await send(path: .postMessage, server: server, data: serverMessage.encoded)
+    }
+    
+    private func send(path: RouteAPI, server: String, data: Data) async -> (state: ClientState, response: Message?) {
+        guard let url = URL(string: server) else {
+            return (.internalError("Invalid server url"), nil)
+        }
+        let fullUrl = url.appendingPathComponent(path.rawValue)
+        return await send(to: fullUrl, data: data)
     }
 
-    private func send(path: RouteAPI, data: Data) async -> (state: ClientState, response: Message?) {
-        let url = server.appendingPathComponent(path.rawValue)
+    private func send(to url: URL, data: Data) async -> (state: ClientState, response: Message?) {
         var request = URLRequest(url: url)
         request.httpBody = data
         request.httpMethod = "POST"
+        request.timeoutInterval = 10
+        return await requestAndDecode(request)
+    }
+    
+    private func requestAndDecode(_ request: URLRequest) async -> (state: ClientState, response: Message?) {
         guard let data = await fulfill(request) else {
             return (.deviceNotAvailable(.serverNotReached), nil)
         }
@@ -36,6 +56,9 @@ struct Client {
         }
         let result = ClientState(keyResult: status)
         guard data.count == Message.length + 1 else {
+            if data.count != 1 {
+                print("Device response with only \(data.count) bytes")
+            }
             return (result, nil)
         }
         let messageData = Array(data.advanced(by: 1))

Sesame/ClientState.swift

@@ -1,5 +1,6 @@
 import Foundation
 import SwiftUI
+import SFSafeSymbols
 
 enum ConnectionError {
     case serverNotReached
@@ -19,6 +20,7 @@ extension ConnectionError: CustomStringConvertible {
 }
 
 enum RejectionCause {
+    case invalidDeviceId
     case invalidCounter
     case invalidTime
     case invalidAuthentication
@@ -30,6 +32,8 @@ extension RejectionCause: CustomStringConvertible {
 
     var description: String {
         switch self {
+        case .invalidDeviceId:
+            return "Invalid device ID"
         case .invalidCounter:
             return "Invalid counter"
         case .invalidTime:
@@ -92,7 +96,10 @@ enum ClientState {
             self = .messageRejected(.timeout)
         case .messageAccepted:
             self = .openSesame
-        case .noBodyData, .invalidMessageData, .textReceived, .unexpectedSocketEvent:
+        case .messageDeviceInvalid:
+            self = .messageRejected(.invalidDeviceId)
+        case .noBodyData, .invalidMessageSize, .textReceived, .unexpectedSocketEvent, .invalidUrlParameter, .invalidResponseAuthentication:
+            print("Unexpected internal error: \(keyResult)")
             self = .internalError(keyResult.description)
         case .deviceNotConnected:
             self = .deviceNotAvailable(.deviceDisconnected)
@@ -137,7 +144,7 @@ enum ClientState {
     
     var allowsAction: Bool {
         switch self {
-        case .requestingStatus, .deviceNotAvailable, .waitingForResponse, .noKeyAvailable:
+        case .noKeyAvailable:
             return false
         default:
             return true
@@ -188,7 +195,7 @@ extension ClientState {
         Data([code])
     }
 
-    private var code: UInt8 {
+    var code: UInt8 {
         switch self {
         case .noKeyAvailable:
             return 1
@@ -207,6 +214,8 @@ extension ClientState {
             return 6
         case .messageRejected(let rejectionCause):
             switch rejectionCause {
+            case .invalidDeviceId:
+                return 19
             case .invalidCounter:
                 return 7
             case .invalidTime:
@@ -230,10 +239,12 @@ extension ClientState {
                 return 15
             case .missingKey:
                 return 16
+            case .invalidDeviceId:
+                return 20
             }
         case .openSesame:
             return 17
-        case .internalError(_):
+        case .internalError:
             return 18
         }
     }
@@ -276,8 +287,35 @@ extension ClientState {
             self = .openSesame
         case 18:
             self = .internalError("")
+        case 19:
+            self = .messageRejected(.invalidDeviceId)
+        case 20:
+            self = .responseRejected(.invalidDeviceId)
         default:
             self = .internalError("Unknown code \(code)")
         }
     }
 }
+
+extension ClientState {
+
+    @available(iOS 16, *)
+    var symbol: SFSymbol {
+        switch self {
+        case .deviceNotAvailable:
+            return .wifiExclamationmark
+        case .internalError:
+            return .applewatchSlash
+        case .noKeyAvailable:
+            return .lockTrianglebadgeExclamationmark
+        case .openSesame:
+            return .lockOpen
+        case .messageRejected:
+            return .nosign
+        case .responseRejected:
+            return .exclamationmarkTriangle
+        case .requestingStatus, .ready, .waitingForResponse:
+            return .wifiExclamationmark
+        }
+    }
+}

Sesame/ContentView.swift

@@ -1,15 +1,25 @@
 import SwiftUI
 import CryptoKit
 
-let server = Client(server: URL(string: "https://christophhagen.de/sesame/")!)
-
 struct ContentView: View {
+    
+    @AppStorage("server")
+    var serverPath: String = "https://christophhagen.de/sesame/"
+    
+    @AppStorage("localIP")
+    var localAddress: String = "192.168.178.104/"
 
     @AppStorage("counter")
     var nextMessageCounter: Int = 0
 
     @AppStorage("compensate")
     var isCompensatingDaylightTime: Bool = false
+    
+    @AppStorage("local")
+    private var useLocalConnection = false
+    
+    @AppStorage("deviceID")
+    private var deviceID: Int = 0
 
     @State
     var keyManager = KeyManagement()
@@ -29,10 +39,15 @@ struct ContentView: View {
     private var responseTime: Date? = nil
 
     @State
-    private var showKeySheet = false
+    private var showSettingsSheet = false
 
     @State
     private var showHistorySheet = false
+    
+    @State
+    private var didShowKeySheetOnce = false
+    
+    let server = Client()
 
     var compensationTime: UInt32 {
         isCompensatingDaylightTime ? 3600 : 0
@@ -77,7 +92,7 @@ struct ContentView: View {
                         .font(.title2)
                         .padding()
                     Spacer()
-                    Button("Keys", action: { showKeySheet = true })
+                    Button("Settings", action: { showSettingsSheet = true })
                         .frame(width: smallButtonWidth,
                                height: smallButtonHeight)
                         .background(.white.opacity(0.2))
@@ -97,7 +112,8 @@ struct ContentView: View {
                            height: buttonWidth)
                     .background(buttonBackground)
                     .cornerRadius(buttonWidth / 2)
-                    .overlay(RoundedRectangle(cornerRadius: buttonWidth / 2).stroke(lineWidth: buttonBorderWidth).foregroundColor(buttonColor))
+                    .overlay(RoundedRectangle(cornerRadius: buttonWidth / 2)
+                        .stroke(lineWidth: buttonBorderWidth).foregroundColor(buttonColor))
                     .foregroundColor(buttonColor)
                     .font(.title)
                     .disabled(!state.allowsAction)
@@ -115,8 +131,15 @@ struct ContentView: View {
             }
             .frame(width: geo.size.width, height: geo.size.height)
             .animation(.easeInOut, value: state.color)
-            .sheet(isPresented: $showKeySheet) {
-                KeyView(keyManager: $keyManager, isCompensatingDaylightTime: $isCompensatingDaylightTime)
+            .sheet(isPresented: $showSettingsSheet) {
+                SettingsView(
+                    keyManager: $keyManager,
+                    serverAddress: $serverPath,
+                    localAddress: $localAddress,
+                    deviceID: $deviceID,
+                    nextMessageCounter: $nextMessageCounter,
+                    isCompensatingDaylightTime: $isCompensatingDaylightTime,
+                    useLocalConnection: $useLocalConnection)
             }
             .sheet(isPresented: $showHistorySheet) {
                 HistoryView(manager: history)
@@ -127,7 +150,8 @@ struct ContentView: View {
     
     func mainButtonPressed() {
         guard let key = keyManager.get(.remoteKey),
-              let token = keyManager.get(.authToken)?.data else {
+              let token = keyManager.get(.authToken)?.data,
+              let deviceId = UInt8(exactly: deviceID) else {
             return
         }
 
@@ -136,37 +160,42 @@ struct ContentView: View {
         // Add time to compensate that the device is using daylight savings time
         let content = Message.Content(
             time: sentTime.timestamp + compensationTime,
-            id: count)
+            id: count,
+            device: deviceId)
         let message = content.authenticate(using: key)
-        let historyItem = HistoryItem(sent: message, date: sentTime)
+        let historyItem = HistoryItem(sent: message.content, date: sentTime, local: useLocalConnection)
         state = .waitingForResponse
         print("Sending message \(count)")
         Task {
-            let (newState, message) = await server.send(message, authToken: token)
+            let (newState, responseMessage) = await send(message, authToken: token)
             let receivedTime = Date.now
             responseTime = receivedTime
             state = newState
-            let finishedItem = historyItem.didReceive(response: newState, date: receivedTime, message: message)
-            process(item: finishedItem)
+            let finishedItem = historyItem.didReceive(response: newState, date: receivedTime, message: responseMessage?.content)
+            guard let key = keyManager.get(.deviceKey) else {
+                save(historyItem: finishedItem.notAuthenticated())
+                return
+            }
+            guard let responseMessage else {
+                save(historyItem: finishedItem)
+                return
+            }
+            guard responseMessage.isValid(using: key) else {
+                save(historyItem: finishedItem.invalidated())
+                return
+            }
+            
+            nextMessageCounter = Int(responseMessage.content.id)
+            save(historyItem: finishedItem)
         }
     }
-
-    private func process(item: HistoryItem) {
-        guard let message = item.incomingMessage else {
-            save(historyItem: item)
-            return
+    
+    private func send(_ message: Message, authToken: Data) async -> (state: ClientState, response: Message?) {
+        if useLocalConnection {
+            return await server.sendMessageOverLocalNetwork(message, server: localAddress)
+        } else {
+            return await server.send(message, server: serverPath, authToken: authToken)
         }
-
-        guard let key = keyManager.get(.deviceKey) else {
-            save(historyItem: item.notAuthenticated())
-            return
-        }
-        guard message.isValid(using: key) else {
-            save(historyItem: item.invalidated())
-            return
-        }
-        nextMessageCounter = Int(message.content.id)
-        save(historyItem: item)
     }
 
     private func save(historyItem: HistoryItem) {
@@ -194,7 +223,14 @@ struct ContentView: View {
     }
     
     func checkDeviceStatus(_ timer: Timer) {
+        guard !useLocalConnection else {
+            return
+        }
         guard let authToken = keyManager.get(.authToken) else {
+            if !didShowKeySheetOnce {
+                didShowKeySheetOnce = true
+                //showSettingsSheet = true
+            }
             return
         }
         guard !hasActiveRequest else {
@@ -202,7 +238,7 @@ struct ContentView: View {
         }
         hasActiveRequest = true
         Task {
-            let newState = await server.deviceStatus(authToken: authToken.data)
+            let newState = await server.deviceStatus(authToken: authToken.data, server: serverPath)
             hasActiveRequest = false
             switch state {
             case .noKeyAvailable:

Sesame/HistoryItem.swift

@@ -1,168 +1,131 @@
 import Foundation
 
+
 struct HistoryItem {
+    
+    
+    /// The sent/received date (local time, not including compensation offset)
+    let requestDate: Date
 
-    let outgoingDate: Date
-
-    let outgoingMessage: Message
-
-    let incomingDate: Date?
-
-    let incomingMessage: Message?
-
+    let request: Message.Content
+    
+    let usedLocalConnection: Bool
+    
     let response: ClientState?
+    
+    let responseMessage: Message.Content?
+    
+    let responseDate: Date?
 
-    init(sent message: Message, date: Date) {
-        self.outgoingDate = date
-        self.outgoingMessage = message
-        self.incomingDate = nil
-        self.incomingMessage = nil
+    init(sent message: Message.Content, date: Date, local: Bool) {
+        self.requestDate = date
+        self.request = message
+        self.responseMessage = nil
         self.response = nil
+        self.responseDate = nil
+        self.usedLocalConnection = local
     }
 
-    func didReceive(response: ClientState, date: Date?, message: Message?) -> HistoryItem {
+    func didReceive(response: ClientState, date: Date?, message: Message.Content?) -> HistoryItem {
         .init(sent: self, response: response, date: date, message: message)
     }
 
     func invalidated() -> HistoryItem {
-        didReceive(response: .responseRejected(.invalidAuthentication), date: incomingDate, message: incomingMessage)
+        didReceive(response: .responseRejected(.invalidAuthentication), date: responseDate, message: responseMessage)
     }
 
     func notAuthenticated() -> HistoryItem {
-        didReceive(response: .responseRejected(.missingKey), date: incomingDate, message: incomingMessage)
+        didReceive(response: .responseRejected(.missingKey), date: responseDate, message: responseMessage)
     }
 
-    private init(sent: HistoryItem, response: ClientState, date: Date?, message: Message?) {
-        self.outgoingDate = sent.outgoingDate
-        self.outgoingMessage = sent.outgoingMessage
-        self.incomingDate = date
-        self.incomingMessage = message
+    private init(sent: HistoryItem, response: ClientState, date: Date?, message: Message.Content?) {
+        self.requestDate = sent.requestDate
+        self.request = sent.request
+        self.responseDate = date
+        self.responseMessage = message
         self.response = response
+        self.usedLocalConnection = sent.usedLocalConnection
     }
 
     // MARK: Statistics
 
     var roundTripTime: TimeInterval? {
-        incomingDate?.timeIntervalSince(outgoingDate)
+        responseDate?.timeIntervalSince(requestDate)
     }
 
     var deviceTime: Date? {
-        guard let timestamp = incomingMessage?.content.time else {
+        guard let timestamp = responseMessage?.time else {
             return nil
         }
         return Date(timestamp: timestamp)
     }
 
     var requestLatency: TimeInterval? {
-        deviceTime?.timeIntervalSince(outgoingDate)
+        deviceTime?.timeIntervalSince(requestDate)
     }
 
     var responseLatency: TimeInterval? {
         guard let deviceTime = deviceTime else {
             return nil
         }
-        return incomingDate?.timeIntervalSince(deviceTime)
+        return responseDate?.timeIntervalSince(deviceTime)
     }
 
     var clockOffset: Int? {
         guard let interval = roundTripTime, let deviceTime = deviceTime else {
             return nil
         }
-        let estimatedArrival = outgoingDate.advanced(by: interval / 2)
+        let estimatedArrival = requestDate.advanced(by: interval / 2)
         return Int(deviceTime.timeIntervalSince(estimatedArrival))
     }
 
-    // MARK: Coding
+}
 
-    static func testEncoding() {
-
-    }
-
-    var encoded: Data {
-        var result = outgoingDate.encoded + outgoingMessage.encoded
-        if let date = incomingDate {
-            result += Data([1]) + date.encoded
-        } else {
-            result += Data([0])
-        }
-        if let message = incomingMessage {
-            result += Data([1]) + message.encoded
-        } else {
-            result += Data([0])
-        }
-        result += response?.encoded ?? Data([0])
-        return result
-    }
-
-    init?(decodeFrom data: Data, index: inout Int) {
-        guard let outgoingDate = Date(decodeFrom: data, index: &index) else {
-            return nil
-        }
-        self.outgoingDate = outgoingDate
-
-        guard let outgoingMessage = Message(decodeFrom: data, index: &index) else {
-            return nil
-        }
-        self.outgoingMessage = outgoingMessage
-
-        if data[index] > 0 {
-            index += 1
-            guard let incomingDate = Date(decodeFrom: data, index: &index) else {
-                return nil
-            }
-            self.incomingDate = incomingDate
-        } else {
-            self.incomingDate = nil
-            index += 1
-        }
-
-        if data[index] > 0 {
-            index += 1
-            guard let incomingMessage = Message(decodeFrom: data, index: &index) else {
-                return nil
-            }
-            self.incomingMessage = incomingMessage
-        } else {
-            self.incomingMessage = nil
-            index += 1
-        }
-        guard index < data.count else {
-            return nil
-        }
-        self.response = ClientState(code: data[index])
-        index += 1
+extension HistoryItem: Codable {
+    
+    enum CodingKeys: Int, CodingKey {
+        case requestDate = 1
+        case request = 2
+        case usedLocalConnection = 3
+        case response = 4
+        case responseMessage = 5
+        case responseDate = 6
     }
 }
 
-private extension Date {
-
-    static var encodedSize: Int {
-        MemoryLayout<Double>.size
+extension ClientState: Codable {
+    
+    init(from decoder: Decoder) throws {
+        let code = try decoder.singleValueContainer().decode(UInt8.self)
+        self.init(code: code)
     }
-
-    var encoded: Data {
-        .init(from: timeIntervalSince1970)
-    }
-
-    init?(decodeFrom data: Data, index: inout Int) {
-        guard index + Date.encodedSize <= data.count else {
-            return nil
-        }
-        self.init(timeIntervalSince1970: data.advanced(by: index).convert(into: .zero))
-        index += Date.encodedSize
+    
+    func encode(to encoder: Encoder) throws {
+        var container = encoder.singleValueContainer()
+        try container.encode(code)
     }
 }
 
 extension HistoryItem: Identifiable {
 
     var id: UInt32 {
-        outgoingDate.timestamp
+        requestDate.timestamp
     }
 }
 
 extension HistoryItem: Comparable {
 
     static func < (lhs: HistoryItem, rhs: HistoryItem) -> Bool {
-        lhs.outgoingDate < rhs.outgoingDate
+        lhs.requestDate < rhs.requestDate
+    }
+}
+
+extension HistoryItem {
+
+    static var mock: HistoryItem {
+        let content = Message.Content(time: Date.now.timestamp, id: 123, device: 0)
+        let content2 = Message.Content(time: (Date.now + 1).timestamp, id: 124, device: 0)
+        return .init(sent: content, date: .now, local: false)
+            .didReceive(response: .openSesame, date: .now + 2, message: content2)
     }
 }

Sesame/HistoryListItem.swift

@@ -1,4 +1,5 @@
 import SwiftUI
+import SFSafeSymbols
 
 private let df: DateFormatter = {
     let df = DateFormatter()
@@ -12,20 +13,20 @@ struct HistoryListItem: View {
     let entry: HistoryItem
 
     var entryTime: String {
-        df.string(from: entry.outgoingDate)
+        df.string(from: entry.requestDate)
     }
 
-    var roundTripText: String {
+    var roundTripText: String? {
         guard let time = entry.roundTripTime else {
-            return ""
+            return nil
         }
-        return "⇆ \(Int(time * 1000)) ms"
+        return "\(Int(time * 1000)) ms"
     }
 
     var counterText: String {
-        let sentCounter = entry.outgoingMessage.content.id
-        let startText = "🔗 \(sentCounter)"
-        guard let rCounter = entry.incomingMessage?.content.id else {
+        let sentCounter = entry.request.id
+        let startText = "\(sentCounter)"
+        guard let rCounter = entry.responseMessage?.id else {
             return startText
         }
         let diff = Int(rCounter) - Int(sentCounter)
@@ -35,15 +36,15 @@ struct HistoryListItem: View {
         return startText + " (\(diff))"
     }
 
-    var timeOffsetText: String {
-        guard let offset = entry.clockOffset, offset != 0 else {
-            return ""
+    var timeOffsetText: String? {
+        guard let offset = entry.clockOffset else {
+            return nil
         }
-        return "🕓 \(offset) s"
+        return "\(offset) s"
     }
     
     var body: some View {
-        VStack {
+        VStack(alignment: .leading) {
             HStack {
                 Text(entry.response?.description ?? "")
                     .font(.headline)
@@ -51,18 +52,21 @@ struct HistoryListItem: View {
                 Text(entryTime)
             }.padding(.bottom, 1)
             HStack {
-                Text(roundTripText)
-                    .font(.subheadline)
-                    .foregroundColor(.secondary)
+                if let roundTripText {
+                    Image(systemSymbol: entry.usedLocalConnection ? .wifi : .network)
+                    Text(roundTripText)
+                        .font(.subheadline)
+                }
+                Image(systemSymbol: .personalhotspot)
                 Text(counterText)
                     .font(.subheadline)
-                    .foregroundColor(.secondary)
-                Text(timeOffsetText)
-                    .font(.subheadline)
-                    .foregroundColor(.secondary)
-                Spacer()
-            }
-        }.padding()
+                if let timeOffsetText {
+                    Image(systemSymbol: .stopwatch)
+                    Text(timeOffsetText)
+                        .font(.subheadline)
+                }
+            }.foregroundColor(.secondary)
+        }
     }
 }
 
@@ -71,19 +75,3 @@ struct HistoryListItem_Previews: PreviewProvider {
         HistoryListItem(entry: .mock)
     }
 }
-
-private extension HistoryItem {
-
-    static var mock: HistoryItem {
-        let mac = Data(repeating: 42, count: 32)
-        let content = Message.Content(time: Date.now.timestamp, id: 123)
-        let content2 = Message.Content(time: (Date.now + 1).timestamp, id: 124)
-        return .init(
-            sent: Message(mac: mac, content: content),
-            date: .now)
-        .didReceive(
-            response: .openSesame,
-            date: .now + 2,
-            message: Message(mac: mac, content: content2))
-    }
-}

Sesame/HistoryManager.swift

@@ -1,59 +1,92 @@
 import Foundation
+import CBORCoding
 
-final class HistoryManager {
+protocol HistoryManagerProtocol {
+    
+    func loadEntries() -> [HistoryItem]
+    
+    func save(item: HistoryItem) throws
+}
+
+final class HistoryManager: HistoryManagerProtocol {
+    
+    private let encoder = CBOREncoder(dateEncodingStrategy: .secondsSince1970)
 
     private var fm: FileManager {
         .default
     }
 
-    var documentDirectory: URL {
-        try! fm.url(
+    static var documentDirectory: URL {
+        try! FileManager.default.url(
         for: .documentDirectory,
         in: .userDomainMask,
         appropriateFor: nil, create: true)
     }
 
-    private var fileUrl: URL {
-        documentDirectory.appendingPathComponent("history.bin")
+    private let fileUrl: URL
+    
+    init() {
+        self.fileUrl = HistoryManager.documentDirectory.appendingPathComponent("history2.bin")
     }
-
+    
     func loadEntries() -> [HistoryItem] {
-        let url = fileUrl
-        guard fm.fileExists(atPath: url.path) else {
+        guard fm.fileExists(atPath: fileUrl.path) else {
             print("No history data found")
             return []
         }
         let content: Data
         do {
-            content = try Data(contentsOf: url)
+            content = try Data(contentsOf: fileUrl)
         } catch {
             print("Failed to read history data: \(error)")
             return []
         }
+        let decoder = CBORDecoder()
         var index = 0
         var entries = [HistoryItem]()
         while index < content.count {
-            guard let entry = HistoryItem(decodeFrom: content, index: &index) else {
-                print("Failed to read entry at index \(index)")
+            let length = Int(content[index])
+            index += 1
+            if index + length > content.count {
+                print("Missing bytes in history file: needed \(length), has only \(content.count - index)")
+                return entries
+            }
+            let entryData = content[index..<index+length]
+            index += length
+            do {
+                let entry: HistoryItem = try decoder.decode(from: entryData)
+                entries.append(entry)
+            } catch {
+                print("Failed to decode history (index: \(index), length \(length)): \(error)")
                 return entries
             }
-            entries.append(entry)
         }
         return entries.sorted().reversed()
     }
 
     func save(item: HistoryItem) throws {
-        let url = fileUrl
-        let data = item.encoded
-        guard fm.fileExists(atPath: url.path) else {
-            try data.write(to: url)
-            print("First history item written")
+        let entryData = try encoder.encode(item)
+        let data = Data([UInt8(entryData.count)]) + entryData
+        guard fm.fileExists(atPath: fileUrl.path) else {
+            try data.write(to: fileUrl)
+            print("First history item written (\(data[0]))")
             return
         }
-        let handle = try FileHandle(forWritingTo: url)
+        let handle = try FileHandle(forWritingTo: fileUrl)
         try handle.seekToEnd()
         try handle.write(contentsOf: data)
         try handle.close()
-        print("History item written")
+        print("History item written (\(data[0]))")
+    }
+}
+
+final class HistoryManagerMock: HistoryManagerProtocol {
+    
+    func loadEntries() -> [HistoryItem] {
+        [.mock]
+    }
+    
+    func save(item: HistoryItem) throws {
+        
     }
 }

Sesame/HistoryView.swift

@@ -2,17 +2,20 @@ import SwiftUI
 
 struct HistoryView: View {
 
-    let manager: HistoryManager
+    let manager: HistoryManagerProtocol
 
     var body: some View {
-        List(manager.loadEntries()) { entry in
-            HistoryListItem(entry: entry)
+        NavigationView {
+            List(manager.loadEntries()) { entry in
+                HistoryListItem(entry: entry)
+            }
+            .navigationTitle("History")
         }
     }
 }
 
 struct HistoryView_Previews: PreviewProvider {
     static var previews: some View {
-        HistoryView(manager: .init())
+        HistoryView(manager: HistoryManagerMock())
     }
 }

Sesame/KeyManagement.swift

@@ -17,11 +17,11 @@ extension KeyManagement {
         var displayName: String {
             switch self {
             case .deviceKey:
-                return "Device Key"
+                return "Unlock Key"
             case .remoteKey:
-                return "Remote Key"
+                return "Response Key"
             case .authToken:
-                return "Authentication Token"
+                return "Server Token"
             }
         }
 
@@ -148,6 +148,15 @@ final class KeyManagement: ObservableObject {
 
     func generate(_ type: KeyType) {
         let key = SymmetricKey(size: type.keyLength)
+        save(type, key: key)
+    }
+    
+    func save(_ type: KeyType, data: Data) {
+        let key = SymmetricKey(data: data)
+        save(type, key: key)
+    }
+    
+    private func save(_ type: KeyType, key: SymmetricKey) {
         if keyChain.has(type) {
             keyChain.delete(type)
         }

Sesame/KeyView.swift

@@ -1,36 +0,0 @@
-import SwiftUI
-
-struct KeyView: View {
-
-    @Binding
-    var keyManager: KeyManagement
-
-    @Binding
-    var isCompensatingDaylightTime: Bool
-
-    var body: some View {
-        ScrollView {
-        VStack(alignment: .leading, spacing: 8) {
-            ForEach(KeyManagement.KeyType.allCases) { keyType in
-                SingleKeyView(
-                    keyManager: $keyManager,
-                    type: keyType)
-            }
-            Toggle(isOn: $isCompensatingDaylightTime) {
-                Text("Compensate daylight savings time")
-            }
-            Text("If the remote has daylight savings time wrongly set, then the time validation will fail. Use this option to send messages with adjusted timestamps. Warning: Incorrect use of this option will allow replay attacks.")
-                .font(.caption)
-                .foregroundColor(.secondary)
-        }.padding()
-    }
-    }
-}
-
-struct KeyView_Previews: PreviewProvider {
-    static var previews: some View {
-        KeyView(
-            keyManager: .constant(KeyManagement()),
-            isCompensatingDaylightTime: .constant(true))
-    }
-}

Sesame/SettingsView.swift

@@ -0,0 +1,168 @@
+import SwiftUI
+
+struct SettingsView: View {
+
+    @Binding
+    var keyManager: KeyManagement
+    
+    @Binding
+    var serverAddress: String
+    
+    @Binding
+    var localAddress: String
+    
+    @Binding
+    var deviceID: Int
+    
+    @Binding
+    var nextMessageCounter: Int
+
+    @Binding
+    var isCompensatingDaylightTime: Bool
+    
+    @Binding
+    var useLocalConnection: Bool
+    
+    @State
+    private var showDeviceIdInput = false
+    
+    @State
+    private var deviceIdText = ""
+    
+    @State
+    private var showCounterInput = false
+    
+    @State
+    private var counterText = ""
+    
+    
+    var body: some View {
+        NavigationView {
+            ScrollView {
+                VStack(alignment: .leading, spacing: 8) {
+                    VStack(alignment: .leading) {
+                        Text("Server address")
+                            .bold()
+                        TextField("Server address", text: $serverAddress)
+                            .foregroundColor(.secondary)
+                            .padding(.leading, 8)
+                    }.padding(.vertical, 8)
+                    VStack(alignment: .leading) {
+                        Text("Local address")
+                            .bold()
+                        TextField("Local address", text: $localAddress)
+                            .foregroundColor(.secondary)
+                            .padding(.leading, 8)
+                    }.padding(.vertical, 8)
+                    Toggle(isOn: $useLocalConnection) {
+                        Text("Use direct connection to device")
+                    }
+                    Text("Attempt to communicate directly with the device. This is useful if the server is unavailable. Requires a WiFi connection on the same network as the device.")
+                        .font(.caption)
+                        .foregroundColor(.secondary)
+                    VStack(alignment: .leading) {
+                        Text("Device id")
+                            .bold()
+                        HStack(alignment: .bottom) {
+                            Text("\(deviceID)")
+                                .font(.system(.body, design: .monospaced))
+                                .foregroundColor(.secondary)
+                                .padding([.trailing, .bottom])
+                            Button("Edit", action: showAlertToChangeDeviceID)
+                                .padding([.horizontal, .bottom])
+                                .padding(.top, 4)
+                        }
+                    }.padding(.vertical, 8)
+                    VStack(alignment: .leading) {
+                        Text("Message counter")
+                            .bold()
+                        HStack(alignment: .bottom) {
+                            Text("\(nextMessageCounter)")
+                                .font(.system(.body, design: .monospaced))
+                                .foregroundColor(.secondary)
+                                .padding([.trailing, .bottom])
+                            Button("Edit", action: showAlertToChangeCounter)
+                                .padding([.horizontal, .bottom])
+                                .padding(.top, 4)
+                        }
+                    }.padding(.vertical, 8)
+                    ForEach(KeyManagement.KeyType.allCases) { keyType in
+                        SingleKeyView(
+                            keyManager: $keyManager,
+                            type: keyType)
+                    }
+                    Toggle(isOn: $isCompensatingDaylightTime) {
+                        Text("Compensate daylight savings time")
+                    }
+                    Text("If the remote has daylight savings time wrongly set, then the time validation will fail. Use this option to send messages with adjusted timestamps. Warning: Incorrect use of this option will allow replay attacks.")
+                        .font(.caption)
+                        .foregroundColor(.secondary)
+                }.padding()
+            }.onDisappear {
+                if !localAddress.hasSuffix("/") {
+                    localAddress += "/"
+                }
+            }
+            .navigationTitle("Settings")
+            .alert("Update device ID", isPresented: $showDeviceIdInput, actions: {
+                TextField("Device ID", text: $deviceIdText)
+                    .keyboardType(.decimalPad)
+                    .font(.system(.body, design: .monospaced))
+                    .foregroundColor(.black)
+                Button("Save", action: saveDeviceID)
+                Button("Cancel", role: .cancel, action: {})
+            }, message: {
+                Text("Enter the device ID")
+            })
+            .alert("Update message counter", isPresented: $showCounterInput, actions: {
+                TextField("Message counter", text: $counterText)
+                    .keyboardType(.decimalPad)
+                    .font(.system(.body, design: .monospaced))
+                    .foregroundColor(.black)
+                Button("Save", action: saveCounter)
+                Button("Cancel", role: .cancel, action: {})
+            }, message: {
+                Text("Enter the message counter")
+            })
+        }
+    }
+    
+    private func showAlertToChangeDeviceID() {
+        deviceIdText = "\(deviceID)"
+        showDeviceIdInput = true
+    }
+    
+    private func saveDeviceID() {
+        guard let id = UInt8(deviceIdText) else {
+            print("Invalid device id '\(deviceIdText)'")
+            return
+        }
+        self.deviceID = Int(id)
+    }
+    
+    private func showAlertToChangeCounter() {
+        counterText = "\(nextMessageCounter)"
+        showCounterInput = true
+    }
+    
+    private func saveCounter() {
+        guard let id = UInt32(counterText) else {
+            print("Invalid message counter '\(counterText)'")
+            return
+        }
+        self.nextMessageCounter = Int(id)
+    }
+}
+
+struct SettingsView_Previews: PreviewProvider {
+    static var previews: some View {
+        SettingsView(
+            keyManager: .constant(KeyManagement()),
+            serverAddress: .constant("https://example.com"),
+            localAddress: .constant("192.168.178.42"),
+            deviceID: .constant(0),
+            nextMessageCounter: .constant(12345678),
+            isCompensatingDaylightTime: .constant(true),
+            useLocalConnection: .constant(false))
+    }
+}

Sesame/SingleKeyView.swift

@@ -8,6 +8,12 @@ struct SingleKeyView: View {
 
     @Binding
     var keyManager: KeyManagement
+    
+    @State
+    private var showEditWindow = false
+    
+    @State
+    private var keyText = ""
 
     let type: KeyManagement.KeyType
 
@@ -54,9 +60,41 @@ struct SingleKeyView: View {
                 .disabled(!hasKey)
                 .padding([.horizontal, .bottom])
                 .padding(.top, 4)
+                Button("Edit") {
+                    keyText = keyManager.get(type)?.displayString ?? ""
+                    print("Set key text to '\(keyText)'")
+                    showEditWindow = true
+                }
+                .padding([.horizontal, .bottom])
+                .padding(.top, 4)
                 Spacer()
             }
         }
+        .alert("Update key", isPresented: $showEditWindow, actions: {
+            TextField("Key data", text: $keyText)
+                .lineLimit(4)
+                .font(.system(.body, design: .monospaced))
+                .foregroundColor(.black)
+            Button("Save", action: saveKey)
+            Button("Cancel", role: .cancel, action: {})
+        }, message: {
+            Text("Enter the hex encoded key")
+        })
+    }
+    
+    private func saveKey() {
+        let cleanText = keyText.replacingOccurrences(of: " ", with: "")
+        guard let keyData = Data(fromHexEncodedString: cleanText) else {
+            print("Invalid key string")
+            return
+        }
+        let keyLength = type.keyLength.bitCount
+        guard keyData.count * 8 == keyLength else {
+            print("Invalid key length \(keyData.count * 8) bits, expected \(keyLength)")
+            return
+        }
+        keyManager.save(type, data: keyData)
+        print("Key \(type) saved")
     }
 }
 
@@ -65,5 +103,6 @@ struct SingleKeyView_Previews: PreviewProvider {
         SingleKeyView(
             keyManager: .constant(KeyManagement()),
             type: .deviceKey)
+        .previewLayout(.fixed(width: 350, height: 100))
     }
 }

Sesame/SymmetricKey+Extensions.swift

@@ -46,3 +46,26 @@ extension String {
         return results.map { String($0) }
     }
 }
+
+let protocolSalt = "CryptoKit Playgrounds Putting It Together".data(using: .utf8)!
+
+/// Generates an ephemeral key agreement key and performs key agreement to get the shared secret and derive the symmetric encryption key.
+func encrypt(_ data: Data, to theirEncryptionKey: Curve25519.KeyAgreement.PublicKey, signedBy ourSigningKey: Curve25519.Signing.PrivateKey) throws ->
+    (ephemeralPublicKeyData: Data, ciphertext: Data, signature: Data) {
+        let ephemeralKey = Curve25519.KeyAgreement.PrivateKey()
+        let ephemeralPublicKey = ephemeralKey.publicKey.rawRepresentation
+        
+        let sharedSecret = try ephemeralKey.sharedSecretFromKeyAgreement(with: theirEncryptionKey)
+        
+        let symmetricKey = sharedSecret.hkdfDerivedSymmetricKey(using: SHA256.self,
+                                                                salt: protocolSalt,
+                                                                sharedInfo: ephemeralPublicKey +
+                                                                    theirEncryptionKey.rawRepresentation +
+                                                                    ourSigningKey.publicKey.rawRepresentation,
+                                                                outputByteCount: 32)
+        
+        let ciphertext = try ChaChaPoly.seal(data, using: symmetricKey).combined
+        let signature = try ourSigningKey.signature(for: ciphertext + ephemeralPublicKey + theirEncryptionKey.rawRepresentation)
+        
+        return (ephemeralPublicKey, ciphertext, signature)
+}