REF: SwiftTCPClient to use Network framework and Backgroud thread

ios/Shared/MarketAPI+Electrum.swift

@@ -15,55 +15,56 @@ struct APIError: LocalizedError {
 extension MarketAPI {
 
   static func fetchNextBlockFee(completion: @escaping ((MarketData?, Error?) -> Void), userElectrumSettings: UserDefaultsElectrumSettings = UserDefaultsGroup.getElectrumSettings()) {
-        let settings = userElectrumSettings
-        let portToUse = settings.sslPort ?? settings.port
-        let isSSLSupported = settings.sslPort != nil
-
-        DispatchQueue.global(qos: .background).async {
+         Task {
              let client = SwiftTCPClient()
-
              defer {
-                print("Closing connection to \(String(describing: settings.host)):\(String(describing: portToUse)).")
+                 print("Closing connection to \(userElectrumSettings.host ?? "unknown"):\(userElectrumSettings.sslPort ?? userElectrumSettings.port ?? 0).")
                  client.close()
              }
 
-            guard let host = settings.host, let portToUse = portToUse else { return }
+             guard let host = userElectrumSettings.host, let portToUse = userElectrumSettings.sslPort ?? userElectrumSettings.port else {
+                 completion(nil, APIError())
+                 return
+             }
 
-            print("Attempting to connect to \(String(describing: settings.host)):\(portToUse) with SSL supported: \(isSSLSupported).")
+             let isSSLSupported = userElectrumSettings.sslPort != nil
+             print("Attempting to connect to \(host):\(portToUse) with SSL supported: \(isSSLSupported).")
 
-            if client.connect(to: host, port: UInt32(portToUse), useSSL: isSSLSupported) {
-                print("Successfully connected to \(String(describing: settings.host)):\(portToUse) with SSL:\(isSSLSupported).")
+             let connected = await client.connect(to: host, port: portToUse, useSSL: isSSLSupported)
+             if connected {
+                 print("Successfully connected to \(host):\(portToUse) with SSL: \(isSSLSupported).")
              } else {
-                print("Failed to connect to \(String(describing: settings.host)):\(portToUse) with SSL:\(isSSLSupported).")
+                 print("Failed to connect to \(host):\(portToUse) with SSL: \(isSSLSupported).")
                  completion(nil, APIError())
                  return
              }
 
              let message = "{\"id\": 1, \"method\": \"mempool.get_fee_histogram\", \"params\": []}\n"
-            guard let data = message.data(using: .utf8), client.send(data: data) else {
-                print("Message sending failed to \(String(describing: settings.host)):\(portToUse) with SSL supported: \(isSSLSupported).")
+             guard let data = message.data(using: .utf8), await client.send(data: data) else {
+                 print("Message sending failed to \(host):\(portToUse) with SSL supported: \(isSSLSupported).")
                  completion(nil, APIError())
                  return
              }
-            print("Message sent successfully to \(String(describing: settings.host)):\(portToUse) with SSL:\(isSSLSupported).")
+             print("Message sent successfully to \(host):\(portToUse) with SSL: \(isSSLSupported).")
 
              do {
-                let receivedData = try client.receive()
+                 let receivedData = try await client.receive()
                  print("Data received. Parsing...")
                  guard let responseString = String(data: receivedData, encoding: .utf8),
                        let responseData = responseString.data(using: .utf8),
                        let json = try JSONSerialization.jsonObject(with: responseData, options: .allowFragments) as? [String: AnyObject],
                        let feeHistogram = json["result"] as? [[Double]] else {
-                    print("Failed to parse response from \(String(describing: settings.host)).")
+                     print("Failed to parse response from \(host).")
                      completion(nil, APIError())
                      return
                  }
 
                  let fastestFee = calcEstimateFeeFromFeeHistogram(numberOfBlocks: 1, feeHistogram: feeHistogram)
-                let marketData = MarketData(nextBlock: String(format: "%.0f", fastestFee), sats: "0", price: "0", rate: 0)
-                completion(marketData, nil) // Successfully fetched data, return it
+                 let marketData = MarketData(nextBlock: String(format: "%.0f", fastestFee), sats: "0", price: "0", rate: 0, dateString: "")
+                 print("Parsed MarketData: \(marketData)")
+                 completion(marketData, nil)
              } catch {
-                print("Error receiving data from \(String(describing: settings.host)): \(error.localizedDescription)")
+                 print("Error receiving data from \(host): \(error.localizedDescription)")
                  completion(nil, APIError())
              }
          }

ios/Shared/UserDefaultsGroup.swift

@@ -9,9 +9,9 @@
 import Foundation
 
 struct UserDefaultsElectrumSettings {
-  let host: String?
-  let port: Int32?
-  let sslPort: Int32?
+    var host: String?
+    var port: UInt16?
+    var sslPort: UInt16?
 }
 
 let hardcodedPeers = [
@@ -34,14 +34,14 @@ class UserDefaultsGroup {
       return DefaultElectrumPeers.randomElement()!
     }
     
-    let electrumSettingsTCPPort = suite?.string(forKey: UserDefaultsGroupKey.ElectrumSettingsTCPPort.rawValue) ?? "50001"
-    let electrumSettingsSSLPort = suite?.string(forKey: UserDefaultsGroupKey.ElectrumSettingsSSLPort.rawValue) ?? "443"
+    let electrumSettingsTCPPort = suite?.value(forKey: UserDefaultsGroupKey.ElectrumSettingsTCPPort.rawValue) ?? 50001
+    let electrumSettingsSSLPort = suite?.value(forKey: UserDefaultsGroupKey.ElectrumSettingsSSLPort.rawValue) ?? 443
     
     let host = electrumSettingsHost
-    let sslPort = Int32(electrumSettingsSSLPort)
-    let port = Int32(electrumSettingsTCPPort)
+    let sslPort = electrumSettingsSSLPort
+    let port = electrumSettingsTCPPort
 
-    return UserDefaultsElectrumSettings(host: host, port: port, sslPort: sslPort)
+    return UserDefaultsElectrumSettings(host: host, port: port as! UInt16, sslPort: sslPort as! UInt16)
   }
   
   static func getAllWalletsBalance() -> Double {

ios/Widgets/Shared/SwiftTCPClient.swift

@@ -1,152 +1,155 @@
-//  BlueWallet
-//
-//  Created by Marcos Rodriguez on 3/23/23.
-//  Copyright © 2023 BlueWallet. All rights reserved.
-
 import Foundation
+import Network
 
-/**
- `SwiftTCPClient` is a simple TCP client class that allows for establishing a TCP connection,
- sending data, and receiving data over the network. It supports both plain TCP and SSL-secured connections.
+enum SwiftTCPClientError: Error, LocalizedError {
+    case connectionNil
+    case connectionCancelled
+    case readTimedOut
+    case noDataReceived
+    case unknown(Error)
     
- The class uses `InputStream` and `OutputStream` for network communication, encapsulating the complexity of stream management and data transfer.
-
- - Note: When using SSL, this implementation disables certificate chain validation for simplicity. This is not recommended for production code due to security risks.
-
- ## Examples
-
- ### Creating an instance and connecting to a server:
-
- ```swift
- let client = SwiftTCPClient()
- let success = client.connect(to: "example.com", port: 12345, useSSL: false)
-
- if success {
-     print("Connected successfully.")
- } else {
-     print("Failed to connect.")
+    var errorDescription: String? {
+        switch self {
+        case .connectionNil:
+            return "Connection is nil."
+        case .connectionCancelled:
+            return "Connection was cancelled."
+        case .readTimedOut:
+            return "Read timed out."
+        case .noDataReceived:
+            return "No data received."
+        case .unknown(let error):
+            return error.localizedDescription
         }
-**/
-
-class SwiftTCPClient: NSObject {
-    private var inputStream: InputStream?
-    private var outputStream: OutputStream?
-    private let bufferSize = 1024
-    private var readData = Data()
-    private let readTimeout = 5.0 // Timeout in seconds
-
-     func connect(to host: String, port: UInt32, useSSL: Bool = false) -> Bool {
-        var readStream: Unmanaged<CFReadStream>?
-        var writeStream: Unmanaged<CFWriteStream>?
-
-        CFStreamCreatePairWithSocketToHost(kCFAllocatorDefault, host as CFString, port, &readStream, &writeStream)
-
-        guard let read = readStream?.takeRetainedValue(), let write = writeStream?.takeRetainedValue() else {
-            return false
     }
+}
 
-        inputStream = read as InputStream
-        outputStream = write as OutputStream
+class SwiftTCPClient {
+    private var connection: NWConnection?
+    private let queue = DispatchQueue(label: "SwiftTCPClientQueue")
+    private let readTimeout: TimeInterval = 5.0
 
+    func connect(to host: String, port: UInt16, useSSL: Bool = false) async -> Bool {
+        let parameters: NWParameters
         if useSSL {
-            // Configure SSL settings for the streams
-            let sslSettings: [NSString: Any] = [
-                kCFStreamSSLLevel as NSString: kCFStreamSocketSecurityLevelNegotiatedSSL as Any,
-                kCFStreamSSLValidatesCertificateChain as NSString: kCFBooleanFalse as Any
-                // Note: Disabling certificate chain validation (kCFStreamSSLValidatesCertificateChain: kCFBooleanFalse)
-                // is typically not recommended for production code as it introduces significant security risks.
-            ]
-            inputStream?.setProperty(sslSettings, forKey: kCFStreamPropertySSLSettings as Stream.PropertyKey)
-            outputStream?.setProperty(sslSettings, forKey: kCFStreamPropertySSLSettings as Stream.PropertyKey)
+            parameters = NWParameters(tls: createTLSOptions(), tcp: .init())
+        } else {
+            parameters = NWParameters.tcp
         }
 
-        inputStream?.delegate = self
-        outputStream?.delegate = self
+        connection = NWConnection(host: NWEndpoint.Host(host), port: NWEndpoint.Port(rawValue: port)!, using: parameters)
+        connection?.start(queue: queue)
 
-        inputStream?.schedule(in: .current, forMode: RunLoop.Mode.default)
-        outputStream?.schedule(in: .current, forMode: RunLoop.Mode.default)
+        let serialQueue = DispatchQueue(label: "SwiftTCPClient.connect.serialQueue")
+        var hasResumed = false
 
-        inputStream?.open()
-        outputStream?.open()
-
-        return true
-    }
-    
-
-    func send(data: Data) -> Bool {
-        guard let outputStream = outputStream else {
-            return false
-        }
-
-        let bytesWritten = data.withUnsafeBytes { bufferPointer -> Int in
-            guard let baseAddress = bufferPointer.baseAddress else {
-                return 0
-            }
-            return outputStream.write(baseAddress.assumingMemoryBound(to: UInt8.self), maxLength: data.count)
-        }
-
-        return bytesWritten == data.count
-    }
-
-    func receive() throws -> Data {
-    guard let inputStream = inputStream else {
-        throw NSError(domain: "SwiftTCPClientError", code: 1, userInfo: [NSLocalizedDescriptionKey: "Input stream is nil."])
-    }
-    
-    // Check if the input stream is ready for reading
-    if inputStream.streamStatus != .open && inputStream.streamStatus != .reading {
-        throw NSError(domain: "SwiftTCPClientError", code: 3, userInfo: [NSLocalizedDescriptionKey: "Stream is not ready for reading."])
-    }
-
-    readData = Data()
-
-    // Wait for data to be available or timeout
-    let timeoutDate = Date().addingTimeInterval(readTimeout)
-    repeat {
-        RunLoop.current.run(mode: RunLoop.Mode.default, before: Date(timeIntervalSinceNow: 0.1))
-        if readData.count > 0 || Date() > timeoutDate {
-            break
-        }
-    } while inputStream.streamStatus == .open || inputStream.streamStatus == .reading
-
-    if readData.count == 0 && Date() > timeoutDate {
-        throw NSError(domain: "SwiftTCPClientError", code: 2, userInfo: [NSLocalizedDescriptionKey: "Read timed out."])
-    }
-
-    return readData
-}
-
-
-    func close() {
-        inputStream?.close()
-        outputStream?.close()
-        inputStream?.remove(from: .current, forMode: RunLoop.Mode.default)
-        outputStream?.remove(from: .current, forMode: RunLoop.Mode.default)
-        inputStream = nil
-        outputStream = nil
-    }
-}
-
-extension SwiftTCPClient: StreamDelegate {
-    func stream(_ aStream: Stream, handle eventCode: Stream.Event) {
-        switch eventCode {
-        case .hasBytesAvailable:
-            if aStream == inputStream, let inputStream = inputStream {
-                let buffer = UnsafeMutablePointer<UInt8>.allocate(capacity: bufferSize)
-                while inputStream.hasBytesAvailable {
-                    let bytesRead = inputStream.read(buffer, maxLength: bufferSize)
-                    if bytesRead > 0 {
-                        readData.append(buffer, count: bytesRead)
-                    }
-                }
-                buffer.deallocate()
-            }
-        case .errorOccurred:
-            print("Stream error occurred")
-        case .endEncountered:
-            close()
+        do {
+            try await withCheckedThrowingContinuation { (continuation: CheckedContinuation<Void, Error>) in
+                connection?.stateUpdateHandler = { [weak self] state in
+                    guard let self = self else { return }
+                    serialQueue.async {
+                        if !hasResumed {
+                            switch state {
+                            case .ready:
+                                self.connection?.stateUpdateHandler = nil
+                                hasResumed = true
+                                continuation.resume()
+                            case .failed(let error):
+                                self.connection?.stateUpdateHandler = nil
+                                hasResumed = true
+                                continuation.resume(throwing: error)
+                            case .cancelled:
+                                self.connection?.stateUpdateHandler = nil
+                                hasResumed = true
+                                continuation.resume(throwing: SwiftTCPClientError.connectionCancelled)
                             default:
                                 break
                             }
                         }
+                    }
+                }
+            }
+            return true
+        } catch {
+            print("Connection failed with error: \(error.localizedDescription)")
+            return false
+        }
+    }
+
+    func send(data: Data) async -> Bool {
+        guard let connection = connection else {
+            print("Send failed: No active connection.")
+            return false
+        }
+        
+        do {
+            try await withCheckedThrowingContinuation { (continuation: CheckedContinuation<Void, Error>) in
+                connection.send(content: data, completion: .contentProcessed { error in
+                    if let error = error {
+                        print("Send error: \(error.localizedDescription)")
+                        continuation.resume(throwing: error)
+                    } else {
+                        continuation.resume()
+                    }
+                })
+            }
+            return true
+        } catch {
+            print("Send failed with error: \(error.localizedDescription)")
+            return false
+        }
+    }
+
+    func receive() async throws -> Data {
+        guard let connection = connection else {
+            throw SwiftTCPClientError.connectionNil
+        }
+
+        return try await withThrowingTaskGroup(of: Data.self) { group in
+            group.addTask {
+                return try await withCheckedThrowingContinuation { (continuation: CheckedContinuation<Data, Error>) in
+                    connection.receive(minimumIncompleteLength: 1, maximumLength: 65536) { data, _, isComplete, error in
+                        if let error = error {
+                            continuation.resume(throwing: SwiftTCPClientError.unknown(error))
+                            return
+                        }
+
+                        if let data = data, !data.isEmpty {
+                            continuation.resume(returning: data)
+                        } else if isComplete {
+                            self.close()
+                            continuation.resume(throwing: SwiftTCPClientError.noDataReceived)
+                        } else {
+                            continuation.resume(throwing: SwiftTCPClientError.readTimedOut)
+                        }
+                    }
+                }
+            }
+            
+            group.addTask {
+                try await Task.sleep(nanoseconds: UInt64(self.readTimeout * 1_000_000_000))
+                throw SwiftTCPClientError.readTimedOut
+            }
+            
+            if let firstResult = try await group.next() {
+                group.cancelAll()
+                return firstResult
+            } else {
+                throw SwiftTCPClientError.readTimedOut
+            }
+        }
+    }
+
+    func close() {
+        connection?.cancel()
+        connection = nil
+    }
+
+    private func createTLSOptions() -> NWProtocolTLS.Options {
+        let tlsOptions = NWProtocolTLS.Options()
+        sec_protocol_options_set_verify_block(tlsOptions.securityProtocolOptions, { _, _, completion in
+            completion(true)
+        }, DispatchQueue.global(qos: .background))
+        return tlsOptions
+    }
 }