pulse-mobile/PulseHealth/Services/KeychainService.swift

import Foundation
import Security

enum KeychainService {
    static let service = "com.daniil.pulsehealth"

    static func save(key: String, value: String) {
        guard let data = value.data(using: .utf8) else { return }
        let query: [String: Any] = [
            kSecClass as String: kSecClassGenericPassword,
            kSecAttrService as String: service,
            kSecAttrAccount as String: key
        ]
        SecItemDelete(query as CFDictionary)
        var add = query
        add[kSecValueData as String] = data
        add[kSecAttrAccessible as String] = kSecAttrAccessibleAfterFirstUnlock
        SecItemAdd(add as CFDictionary, nil)
    }

    static func load(key: String) -> String? {
        let query: [String: Any] = [
            kSecClass as String: kSecClassGenericPassword,
            kSecAttrService as String: service,
            kSecAttrAccount as String: key,
            kSecReturnData as String: true,
            kSecMatchLimit as String: kSecMatchLimitOne
        ]
        var result: AnyObject?
        guard SecItemCopyMatching(query as CFDictionary, &result) == errSecSuccess,
              let data = result as? Data else { return nil }
        return String(data: data, encoding: .utf8)
    }

    static func delete(key: String) {
        let query: [String: Any] = [
            kSecClass as String: kSecClassGenericPassword,
            kSecAttrService as String: service,
            kSecAttrAccount as String: key
        ]
        SecItemDelete(query as CFDictionary)
    }

    // Keys
    static let tokenKey = "auth_token"
    static let refreshTokenKey = "auth_refresh_token"
    static let healthTokenKey = "health_jwt_token"
    static let healthApiKeyKey = "health_api_key"
}