Add connection check in settings

Sesame/Common/RequestCoordinator.swift

@@ -41,6 +41,23 @@ final class RequestCoordinator: ObservableObject {
         }
     }
     
+    func checkConnection(using route: TransmissionType? = nil) {
+        guard !isPerformingRequest else {
+            return
+        }
+        isPerformingRequest = true
+        Task {
+            let route = route ?? connectionType.transmissionTypes.first!
+            let (finalResult, _) = await performChallenge(route: route)
+            DispatchQueue.main.async {
+                self.state = finalResult.result
+                self.isPerformingRequest = false
+            }
+            print("Finished connection test: \(finalResult)")
+            scheduleReturnToReadyState()
+        }
+    }
+    
     func startUnlock() {
         guard !isPerformingRequest else {
             return

Sesame/ContentView.swift

@@ -73,7 +73,8 @@ struct ContentView: View {
         .animation(.easeInOut, value: coordinator.state.color)
         .sheet(isPresented: $showSettingsSheet) {
             SettingsView(
-                keyManager: coordinator.keyManager,
+                keyManager: coordinator.keyManager, 
+                coordinator: coordinator,
                 serverAddress: $coordinator.serverPath,
                 localAddress: $coordinator.localAddress)
         }

Sesame/SettingsView.swift

@@ -1,9 +1,14 @@
 import SwiftUI
+import SwiftData
+import SFSafeSymbols
 
 struct SettingsView: View {
 
     let keyManager: KeyManagement
     
+    @ObservedObject
+    var coordinator: RequestCoordinator
+    
     @Binding
     var serverAddress: String
     
@@ -20,6 +25,19 @@ struct SettingsView: View {
                         TextField("Server address", text: $serverAddress)
                             .foregroundColor(.secondary)
                             .padding(.leading, 8)
+                        HStack {
+                            Button("Test") {
+                                coordinator.checkConnection(using: .throughServer)
+                            }.padding(8)
+                            if coordinator.state == .deviceAvailable {
+                                Image(systemSymbol: .checkmarkCircle)
+                                    .foregroundColor(.green)
+                            } else if coordinator.state != .notChecked {
+                                Text(coordinator.state.description)
+                                    .font(.caption)
+                                    .foregroundStyle(.secondary)
+                            }
+                        }
                     }.padding(.vertical, 8)
                     VStack(alignment: .leading) {
                         Text("Local address")
@@ -44,11 +62,20 @@ struct SettingsView: View {
     }
 }
 
-struct SettingsView_Previews: PreviewProvider {
-    static var previews: some View {
-        SettingsView(
+#Preview {
+    do {
+        let config = ModelConfiguration(isStoredInMemoryOnly: true)
+        let container = try ModelContainer(for: HistoryItem.self, configurations: config)
+        
+        let item = HistoryItem.mock
+        container.mainContext.insert(item)
+        try container.mainContext.save()
+        return SettingsView(
             keyManager: KeyManagement(),
+            coordinator: .init(modelContext: container.mainContext),
             serverAddress: .constant("https://example.com"),
             localAddress: .constant("192.168.178.42"))
+    } catch {
+        fatalError("Failed to create model container.")
     }
 }