NetworkSecurityManager.swift

NetworkSecurityManager.swift

import Foundation
import CryptoKit
import Network

public final class NetworkSecurityManager {

    public static let shared = NetworkSecurityManager()

    private let monitor = NWPathMonitor()
    private let queue = DispatchQueue(label: "NetworkMonitor")

    private init() {
        setupNetworkMonitoring()
    }

    public func createSecureURLRequest(url: URL,
                                       method: String = "GET",
                                       body: Data? = nil) -> URLRequest {
        var request = URLRequest(url: url)
        request.httpMethod = method
        request.httpBody = body

        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
        request.setValue(generateRequestSignature(), forHTTPHeaderField: "X-Request-Signature")
        request.setValue(UUID().uuidString, forHTTPHeaderField: "X-Request-ID")
        request.setValue(String(Date().timeIntervalSince1970), forHTTPHeaderField: "X-Timestamp")

        return request
    }

    private func generateRequestSignature() -> String {
        let timestamp = String(Date().timeIntervalSince1970)
        let nonce = UUID().uuidString
        let secretKey = "YOUR_SECRET_KEY"

        let signatureData = "\(timestamp):\(nonce):\(secretKey)".data(using: .utf8)!
        let hash = SHA256.hash(data: signatureData)

        return hash.compactMap { String(format: "%02x", $0) }.joined()
    }

    private func setupNetworkMonitoring() {
        monitor.pathUpdateHandler = { [weak self] path in
            self?.handleNetworkChange(path)
        }
        monitor.start(queue: queue)
    }

    private func handleNetworkChange(_ path: NWPath) {
        let isConstrained = path.isConstrained
        let isExpensive = path.isExpensive

        NotificationCenter.default.post(
            name: .networkConditionsChanged,
            object: nil,
            userInfo: [
                "isExpensive": isExpensive,
                "isConstrained": isConstrained,
                "interface": path.availableInterfaces.first?.type.stringValue ?? "unknown"
            ]
        )
    }
}

extension Notification.Name {
    static let networkConditionsChanged = Notification.Name("NetworkConditionsChanged")
}

private extension NWInterface.InterfaceType {
    var stringValue: String {
        switch self {
        case .wifi: return "wifi"
        case .cellular: return "cellular"
        case .wiredEthernet: return "wiredEthernet"
        case .loopback: return "loopback"
        case .other: return "other"
        @unknown default: return "unknown"
        }
    }
}