TextCipherImpl.swift

import Security
import CryptoKit
import shared

final class TextCipherImpl: StringCipher {
    
    func decrypt(securityKey secretKey: SecurityKey, encryptedData: BinaryData) -> String {
        let key = secretKey.key()
        guard let sealedBox = try? AES.GCM.SealedBox(combined: (encryptedData as! BinaryDataImpl).data),
              let decryptedData = try? AES.GCM.open(sealedBox, using: key),
              let decryptedString = String(data: decryptedData, encoding: .utf8) else { fatalError("Decryption failed") }
        return decryptedString
        
    }
    
    func encrypt(securityKey secretKey: SecurityKey, plainData: String) -> BinaryData {
        let key = secretKey.key()
        guard let data = plainData.data(using: .utf8) else { fatalError("Encryption failed") }
        let sealedBox = try! AES.GCM.seal(data, using: key)
        return sealedBox.combined!.toBinaryData()
    }
}