refactor: Optimize server connectivity with Clean Architecture

- Replace ServerConnectivity with CheckServerReachabilityUseCase
- Add InfoApiClient for /api/info endpoint
- Implement ServerInfoRepository with 30s cache TTL and 5s rate limiting
- Update ShareBookmarkViewModel to use ShareExtensionServerCheck manager
- Add server reachability check in AppViewModel on app start
- Update OfflineSyncManager to use new UseCase
- Extend SimpleAPI with checkServerReachability for Share Extension

URLShare/ServerConnectivity.swift

@@ -1,62 +0,0 @@
-import Foundation
-import Network
-
-class ServerConnectivity: ObservableObject {
-    @Published var isServerReachable = false
-    
-    static let shared = ServerConnectivity()
-    
-    private init() {}
-    
-    // Check if the Readeck server endpoint is reachable
-    static func isServerReachable() async -> Bool {
-        guard let endpoint = KeychainHelper.shared.loadEndpoint(),
-              !endpoint.isEmpty,
-              let url = URL(string: endpoint + "/api/health") else {
-            return false
-        }
-        
-        var request = URLRequest(url: url)
-        request.httpMethod = "GET"
-        request.timeoutInterval = 5.0 // 5 second timeout
-        
-        do {
-            let (_, response) = try await URLSession.shared.data(for: request)
-            if let httpResponse = response as? HTTPURLResponse {
-                return httpResponse.statusCode == 200
-            }
-        } catch {
-            print("Server connectivity check failed: \(error)")
-        }
-        
-        return false
-    }
-    
-    // Alternative check using ping-style endpoint
-    static func isServerReachableSync() -> Bool {
-        guard let endpoint = KeychainHelper.shared.loadEndpoint(),
-              !endpoint.isEmpty,
-              let url = URL(string: endpoint) else {
-            return false
-        }
-        
-        let semaphore = DispatchSemaphore(value: 0)
-        var isReachable = false
-        
-        var request = URLRequest(url: url)
-        request.httpMethod = "HEAD" // Just check if server responds
-        request.timeoutInterval = 3.0
-        
-        let task = URLSession.shared.dataTask(with: request) { _, response, error in
-            if let httpResponse = response as? HTTPURLResponse {
-                isReachable = httpResponse.statusCode < 500 // Accept any response that's not server error
-            }
-            semaphore.signal()
-        }
-        
-        task.resume()
-        _ = semaphore.wait(timeout: .now() + 3.0)
-        
-        return isReachable
-    }
-}

URLShare/ShareBookmarkViewModel.swift

@@ -15,6 +15,7 @@ class ShareBookmarkViewModel: ObservableObject {
     let extensionContext: NSExtensionContext?
 
     private let logger = Logger.viewModel
+    private let serverCheck = ShareExtensionServerCheck.shared
         
     var availableLabels: [BookmarkLabelDto] {
         return labels.filter { !selectedLabels.contains($0.name) }
@@ -56,10 +57,15 @@ class ShareBookmarkViewModel: ObservableObject {
     
     private func checkServerReachability() {
         let measurement = PerformanceMeasurement(operation: "checkServerReachability", logger: logger)
-        isServerReachable = ServerConnectivity.isServerReachableSync()
+        Task {
-        logger.info("Server reachability checked: \(isServerReachable)")
+            let reachable = await serverCheck.checkServerReachability()
+            await MainActor.run {
+                self.isServerReachable = reachable
+                logger.info("Server reachability checked: \(reachable)")
                 measurement.end()
             }
+        }
+    }
     
     private func extractSharedContent() {
         logger.debug("Starting to extract shared content")
@@ -131,7 +137,7 @@ class ShareBookmarkViewModel: ObservableObject {
         let measurement = PerformanceMeasurement(operation: "loadLabels", logger: logger)
         logger.debug("Starting to load labels")
         Task {
-            let serverReachable = ServerConnectivity.isServerReachableSync()
+            let serverReachable = await serverCheck.checkServerReachability()
             logger.debug("Server reachable for labels: \(serverReachable)")
 
             if serverReachable {
@@ -170,12 +176,12 @@ class ShareBookmarkViewModel: ObservableObject {
         logger.debug("Set saving state to true")
 
         // Check server connectivity
-        let serverReachable = ServerConnectivity.isServerReachableSync()
+        Task {
+            let serverReachable = await serverCheck.checkServerReachability()
             logger.debug("Server connectivity for save: \(serverReachable)")
             if serverReachable {
                 // Online - try to save via API
                 logger.info("Attempting to save bookmark via API")
-            Task {
                 await SimpleAPI.addBookmark(title: title, url: url, labels: Array(selectedLabels)) { [weak self] message, error in
                     self?.logger.info("API save completed - Success: \(!error), Message: \(message)")
                     self?.statusMessage = (message, error, error ? "❌" : "✅")
@@ -189,7 +195,6 @@ class ShareBookmarkViewModel: ObservableObject {
                         self?.logger.error("Failed to save bookmark via API: \(message)")
                     }
                 }
-            }
             } else {
                 // Server not reachable - save locally
                 logger.info("Server not reachable, attempting local save")
@@ -215,6 +220,7 @@ class ShareBookmarkViewModel: ObservableObject {
                 }
             }
         }
+    }
     
     private func completeExtensionRequest() {
         logger.debug("Completing extension request")

URLShare/ShareExtensionServerCheck.swift

@@ -0,0 +1,41 @@
+import Foundation
+
+/// Simple server check manager for Share Extension with caching
+class ShareExtensionServerCheck {
+    static let shared = ShareExtensionServerCheck()
+
+    // Cache properties
+    private var cachedResult: Bool?
+    private var lastCheckTime: Date?
+    private let cacheTTL: TimeInterval = 30.0
+
+    private init() {}
+
+    func checkServerReachability() async -> Bool {
+        // Check cache first
+        if let cached = getCachedResult() {
+            return cached
+        }
+
+        // Use SimpleAPI for actual check
+        let result = await SimpleAPI.checkServerReachability()
+        updateCache(result: result)
+        return result
+    }
+
+    // MARK: - Cache Management
+
+    private func getCachedResult() -> Bool? {
+        guard let lastCheck = lastCheckTime,
+              Date().timeIntervalSince(lastCheck) < cacheTTL,
+              let cached = cachedResult else {
+            return nil
+        }
+        return cached
+    }
+
+    private func updateCache(result: Bool) {
+        cachedResult = result
+        lastCheckTime = Date()
+    }
+}

URLShare/SimpleAPI.swift

@@ -3,6 +3,39 @@ import Foundation
 class SimpleAPI {
     private static let logger = Logger.network
 
+    // MARK: - Server Info
+
+    static func checkServerReachability() async -> Bool {
+        guard let endpoint = KeychainHelper.shared.loadEndpoint(),
+              !endpoint.isEmpty,
+              let url = URL(string: "\(endpoint)/api/info") else {
+            return false
+        }
+
+        var request = URLRequest(url: url)
+        request.httpMethod = "GET"
+        request.setValue("application/json", forHTTPHeaderField: "accept")
+        request.timeoutInterval = 5.0
+
+        if let token = KeychainHelper.shared.loadToken() {
+            request.setValue("Bearer \(token)", forHTTPHeaderField: "authorization")
+        }
+
+        do {
+            let (data, response) = try await URLSession.shared.data(for: request)
+            if let httpResponse = response as? HTTPURLResponse,
+               200...299 ~= httpResponse.statusCode {
+                logger.info("Server is reachable")
+                return true
+            }
+        } catch {
+            logger.error("Server reachability check failed: \(error.localizedDescription)")
+            return false
+        }
+
+        return false
+    }
+
     // MARK: - API Methods
     static func addBookmark(title: String, url: String, labels: [String]? = nil, showStatus: @escaping (String, Bool) -> Void) async {
         logger.info("Adding bookmark: \(url)")

URLShare/SimpleAPIDTOs.swift

@@ -1,5 +1,17 @@
 import Foundation
 
+public struct ServerInfoDto: Codable {
+    public let version: String
+    public let buildDate: String?
+    public let userAgent: String?
+
+    public enum CodingKeys: String, CodingKey {
+        case version
+        case buildDate = "build_date"
+        case userAgent = "user_agent"
+    }
+}
+
 public struct CreateBookmarkRequestDto: Codable {
     public let labels: [String]?
     public let title: String?
@@ -33,4 +45,3 @@ public struct BookmarkLabelDto: Codable, Identifiable {
         self.href = href
     }
 } 
-

readeck/Data/API/DTOs/ServerInfoDto.swift

@@ -0,0 +1,13 @@
+import Foundation
+
+struct ServerInfoDto: Codable {
+    let version: String
+    let buildDate: String?
+    let userAgent: String?
+
+    enum CodingKeys: String, CodingKey {
+        case version
+        case buildDate = "build_date"
+        case userAgent = "user_agent"
+    }
+}

readeck/Data/API/InfoApiClient.swift

@@ -0,0 +1,55 @@
+//
+//  InfoApiClient.swift
+//  readeck
+//
+//  Created by Claude Code
+
+import Foundation
+
+protocol PInfoApiClient {
+    func getServerInfo() async throws -> ServerInfoDto
+}
+
+class InfoApiClient: PInfoApiClient {
+    private let tokenProvider: TokenProvider
+    private let logger = Logger.network
+
+    init(tokenProvider: TokenProvider = KeychainTokenProvider()) {
+        self.tokenProvider = tokenProvider
+    }
+
+    func getServerInfo() async throws -> ServerInfoDto {
+        guard let endpoint = await tokenProvider.getEndpoint(),
+              let url = URL(string: "\(endpoint)/api/info") else {
+            logger.error("Invalid endpoint URL for server info")
+            throw APIError.invalidURL
+        }
+
+        var request = URLRequest(url: url)
+        request.httpMethod = "GET"
+        request.setValue("application/json", forHTTPHeaderField: "accept")
+        request.timeoutInterval = 5.0
+
+        if let token = await tokenProvider.getToken() {
+            request.setValue("Bearer \(token)", forHTTPHeaderField: "authorization")
+        }
+
+        logger.logNetworkRequest(method: "GET", url: url.absoluteString)
+
+        let (data, response) = try await URLSession.shared.data(for: request)
+
+        guard let httpResponse = response as? HTTPURLResponse else {
+            logger.error("Invalid HTTP response for server info")
+            throw APIError.invalidResponse
+        }
+
+        guard 200...299 ~= httpResponse.statusCode else {
+            logger.logNetworkError(method: "GET", url: url.absoluteString, error: APIError.serverError(httpResponse.statusCode))
+            throw APIError.serverError(httpResponse.statusCode)
+        }
+
+        logger.logNetworkRequest(method: "GET", url: url.absoluteString, statusCode: httpResponse.statusCode)
+
+        return try JSONDecoder().decode(ServerInfoDto.self, from: data)
+    }
+}

readeck/Data/Repository/OfflineSyncManager.swift

@@ -10,16 +10,19 @@ class OfflineSyncManager: ObservableObject, @unchecked Sendable {
 
     private let coreDataManager = CoreDataManager.shared
     private let api: PAPI
+    private let checkServerReachabilityUseCase: PCheckServerReachabilityUseCase
 
-    init(api: PAPI = API()) {
+    init(api: PAPI = API(),
+         checkServerReachabilityUseCase: PCheckServerReachabilityUseCase = DefaultUseCaseFactory.shared.makeCheckServerReachabilityUseCase()) {
         self.api = api
+        self.checkServerReachabilityUseCase = checkServerReachabilityUseCase
     }
     
     // MARK: - Sync Methods
     
     func syncOfflineBookmarks() async {
         // First check if server is reachable
-        guard await ServerConnectivity.isServerReachable() else {
+        guard await checkServerReachabilityUseCase.execute() else {
             await MainActor.run {
                 isSyncing = false
                 syncStatus = "Server not reachable. Cannot sync."

readeck/Data/Repository/ServerInfoRepository.swift

@@ -0,0 +1,114 @@
+//
+//  ServerInfoRepository.swift
+//  readeck
+//
+//  Created by Claude Code
+
+import Foundation
+
+class ServerInfoRepository: PServerInfoRepository {
+    private let apiClient: PInfoApiClient
+    private let logger = Logger.network
+
+    // Cache properties
+    private var cachedServerInfo: ServerInfo?
+    private var lastCheckTime: Date?
+    private let cacheTTL: TimeInterval = 30.0 // 30 seconds cache
+    private let rateLimitInterval: TimeInterval = 5.0 // min 5 seconds between requests
+
+    // Thread safety
+    private let queue = DispatchQueue(label: "com.readeck.serverInfoRepository", attributes: .concurrent)
+
+    init(apiClient: PInfoApiClient) {
+        self.apiClient = apiClient
+    }
+
+    func checkServerReachability() async -> Bool {
+        // Check cache first
+        if let cached = getCachedReachability() {
+            logger.debug("Server reachability from cache: \(cached)")
+            return cached
+        }
+
+        // Check rate limiting
+        if isRateLimited() {
+            logger.debug("Server reachability check rate limited, using cached value")
+            return cachedServerInfo?.isReachable ?? false
+        }
+
+        // Perform actual check
+        do {
+            let info = try await apiClient.getServerInfo()
+            let serverInfo = ServerInfo(from: info)
+            updateCache(serverInfo: serverInfo)
+            logger.info("Server reachability checked: true (version: \(info.version))")
+            return true
+        } catch {
+            let unreachableInfo = ServerInfo.unreachable
+            updateCache(serverInfo: unreachableInfo)
+            logger.warning("Server reachability check failed: \(error.localizedDescription)")
+            return false
+        }
+    }
+
+    func getServerInfo() async throws -> ServerInfo {
+        // Check cache first
+        if let cached = getCachedServerInfo() {
+            logger.debug("Server info from cache")
+            return cached
+        }
+
+        // Check rate limiting
+        if isRateLimited(), let cached = cachedServerInfo {
+            logger.debug("Server info check rate limited, using cached value")
+            return cached
+        }
+
+        // Fetch fresh info
+        let dto = try await apiClient.getServerInfo()
+        let serverInfo = ServerInfo(from: dto)
+        updateCache(serverInfo: serverInfo)
+        logger.info("Server info fetched: version \(dto.version)")
+        return serverInfo
+    }
+
+    // MARK: - Cache Management
+
+    private func getCachedReachability() -> Bool? {
+        queue.sync {
+            guard let lastCheck = lastCheckTime,
+                  Date().timeIntervalSince(lastCheck) < cacheTTL,
+                  let cached = cachedServerInfo else {
+                return nil
+            }
+            return cached.isReachable
+        }
+    }
+
+    private func getCachedServerInfo() -> ServerInfo? {
+        queue.sync {
+            guard let lastCheck = lastCheckTime,
+                  Date().timeIntervalSince(lastCheck) < cacheTTL,
+                  let cached = cachedServerInfo else {
+                return nil
+            }
+            return cached
+        }
+    }
+
+    private func isRateLimited() -> Bool {
+        queue.sync {
+            guard let lastCheck = lastCheckTime else {
+                return false
+            }
+            return Date().timeIntervalSince(lastCheck) < rateLimitInterval
+        }
+    }
+
+    private func updateCache(serverInfo: ServerInfo) {
+        queue.async(flags: .barrier) { [weak self] in
+            self?.cachedServerInfo = serverInfo
+            self?.lastCheckTime = Date()
+        }
+    }
+}

readeck/Domain/Model/ServerInfo.swift

@@ -0,0 +1,21 @@
+import Foundation
+
+struct ServerInfo {
+    let version: String
+    let buildDate: String?
+    let userAgent: String?
+    let isReachable: Bool
+}
+
+extension ServerInfo {
+    init(from dto: ServerInfoDto) {
+        self.version = dto.version
+        self.buildDate = dto.buildDate
+        self.userAgent = dto.userAgent
+        self.isReachable = true
+    }
+
+    static var unreachable: ServerInfo {
+        ServerInfo(version: "", buildDate: nil, userAgent: nil, isReachable: false)
+    }
+}

readeck/Domain/Protocols/PServerInfoRepository.swift

@@ -0,0 +1,10 @@
+//
+//  PServerInfoRepository.swift
+//  readeck
+//
+//  Created by Claude Code
+
+protocol PServerInfoRepository {
+    func checkServerReachability() async -> Bool
+    func getServerInfo() async throws -> ServerInfo
+}

readeck/Domain/UseCase/CheckServerReachabilityUseCase.swift

@@ -0,0 +1,28 @@
+//
+//  CheckServerReachabilityUseCase.swift
+//  readeck
+//
+//  Created by Claude Code
+
+import Foundation
+
+protocol PCheckServerReachabilityUseCase {
+    func execute() async -> Bool
+    func getServerInfo() async throws -> ServerInfo
+}
+
+class CheckServerReachabilityUseCase: PCheckServerReachabilityUseCase {
+    private let repository: PServerInfoRepository
+
+    init(repository: PServerInfoRepository) {
+        self.repository = repository
+    }
+
+    func execute() async -> Bool {
+        return await repository.checkServerReachability()
+    }
+
+    func getServerInfo() async throws -> ServerInfo {
+        return try await repository.getServerInfo()
+    }
+}

readeck/UI/AppViewModel.swift

@@ -11,15 +11,20 @@ import SwiftUI
 class AppViewModel: ObservableObject {
     private let settingsRepository = SettingsRepository()
     private let logoutUseCase: LogoutUseCase
+    private let checkServerReachabilityUseCase: PCheckServerReachabilityUseCase
 
     @Published var hasFinishedSetup: Bool = true
+    @Published var isServerReachable: Bool = false
 
-    init(logoutUseCase: LogoutUseCase = LogoutUseCase()) {
+    init(logoutUseCase: LogoutUseCase = LogoutUseCase(),
+         checkServerReachabilityUseCase: PCheckServerReachabilityUseCase = DefaultUseCaseFactory.shared.makeCheckServerReachabilityUseCase()) {
         self.logoutUseCase = logoutUseCase
+        self.checkServerReachabilityUseCase = checkServerReachabilityUseCase
         setupNotificationObservers()
 
         Task {
             await loadSetupStatus()
+            await checkServerReachability()
         }
     }
     
@@ -65,6 +70,11 @@ class AppViewModel: ObservableObject {
         hasFinishedSetup = settingsRepository.hasFinishedSetup
     }
 
+    @MainActor
+    private func checkServerReachability() async {
+        isServerReachable = await checkServerReachabilityUseCase.execute()
+    }
+
     deinit {
         NotificationCenter.default.removeObserver(self)
     }

readeck/UI/Factory/DefaultUseCaseFactory.swift

@@ -20,6 +20,7 @@ protocol UseCaseFactory {
     func makeOfflineBookmarkSyncUseCase() -> POfflineBookmarkSyncUseCase
     func makeLoadCardLayoutUseCase() -> PLoadCardLayoutUseCase
     func makeSaveCardLayoutUseCase() -> PSaveCardLayoutUseCase
+    func makeCheckServerReachabilityUseCase() -> PCheckServerReachabilityUseCase
 }
 
 
@@ -30,6 +31,8 @@ class DefaultUseCaseFactory: UseCaseFactory {
     private lazy var authRepository: PAuthRepository = AuthRepository(api: api, settingsRepository: settingsRepository)
     private lazy var bookmarksRepository: PBookmarksRepository = BookmarksRepository(api: api)
     private let settingsRepository: PSettingsRepository = SettingsRepository()
+    private lazy var infoApiClient: PInfoApiClient = InfoApiClient(tokenProvider: tokenProvider)
+    private lazy var serverInfoRepository: PServerInfoRepository = ServerInfoRepository(apiClient: infoApiClient)
 
     static let shared = DefaultUseCaseFactory()
 
@@ -112,4 +115,8 @@ class DefaultUseCaseFactory: UseCaseFactory {
     func makeSaveCardLayoutUseCase() -> PSaveCardLayoutUseCase {
         return SaveCardLayoutUseCase(settingsRepository: settingsRepository)
     }
+
+    func makeCheckServerReachabilityUseCase() -> PCheckServerReachabilityUseCase {
+        return CheckServerReachabilityUseCase(repository: serverInfoRepository)
+    }
 }

readeck/UI/Menu/OfflineBookmarksViewModel.swift

@@ -11,8 +11,8 @@ class OfflineBookmarksViewModel {
     private let successDelaySubject = PassthroughSubject<Int, Never>()
     private var completionTimerActive = false
     
-    init(syncUseCase: POfflineBookmarkSyncUseCase = OfflineBookmarkSyncUseCase()) {
+    init(_ factory: UseCaseFactory = DefaultUseCaseFactory.shared) {
-        self.syncUseCase = syncUseCase
+        self.syncUseCase = factory.makeOfflineBookmarkSyncUseCase()
         setupBindings()
         refreshState()
     }

readeck/UI/Menu/PhoneTabView.swift

@@ -12,7 +12,7 @@ struct PhoneTabView: View {
     private let moreTabs: [SidebarTab] = [.article, .videos, .pictures, .tags, .settings]
 
     @State private var selectedTab: SidebarTab = .unread
-    @State private var offlineBookmarksViewModel = OfflineBookmarksViewModel(syncUseCase: DefaultUseCaseFactory.shared.makeOfflineBookmarkSyncUseCase())
+    @State private var offlineBookmarksViewModel = OfflineBookmarksViewModel()
 
     // Navigation paths for each tab
     @State private var allPath = NavigationPath()
@@ -149,9 +149,9 @@ struct PhoneTabView: View {
                 .padding()
         } else if let bookmarks = searchViewModel.bookmarks?.bookmarks, !bookmarks.isEmpty {
             List(bookmarks) { bookmark in
-                // Hidden NavigationLink to remove disclosure indicator
-                // To restore: uncomment block below and remove ZStack
                 ZStack {
+                    
+                    // Hidden NavigationLink to remove disclosure indicator
                     NavigationLink {
                         BookmarkDetailView(bookmarkId: bookmark.id)                            
                     } label: {

readeck/UI/readeckApp.swift

@@ -29,8 +29,6 @@ struct readeckApp: App {
                 #if DEBUG
                 NFX.sharedInstance().start()
                 #endif
-                // Initialize server connectivity monitoring
-                _ = ServerConnectivity.shared
                 Task {
                     await loadAppSettings()
                 }