import Foundation
import Security

final class KeychainHelper {
    static let shared = KeychainHelper()

    private let service = "com.xorbitlab.bugger"

    private init() {}

    func write(_ value: String, forKey key: String) {
        let data = Data(value.utf8)
        let query: [String: Any] = [
            kSecClass as String: kSecClassGenericPassword,
            kSecAttrService as String: service,
            kSecAttrAccount as String: key,
            kSecValueData as String: data
        ]
        SecItemDelete(query as CFDictionary)
        SecItemAdd(query as CFDictionary, nil)
    }

    func read(_ 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)
    }

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