import Crypto  // Equivalent to CryptoKit (more or less)
import Foundation


//  ------------------
//  --- Sign ---------
//  ------------------
public func signP521(object: Data, key: P521.Signing.PrivateKey)throws -> Data {
    return try key.signature<Data>(for: object).rawRepresentation

}
/* 
public func sign<T>(object: T, key: P521.Signing.PrivateKey) throws -> String {

    var _object = object
    let data: Data = Data(bytes: &_object, count: MemoryLayout<T>.stride)

} */



//  ------------------
//  --- Decrypt ------
//  ------------------
public func verifySignatureP521(signature: Data, object: Data, key: P521.Signing.PublicKey) throws -> Bool {

    let ecdsa: P521.Signing.ECDSASignature

    do {
        ecdsa = try P521.Signing.ECDSASignature(rawRepresentation: signature)
    } catch {
        throw SecurityError.NotDecodableError
    }

    return key.isValidSignature<Data>(ecdsa, for: object)
}



//  ------------------
//  --- PEM 2 Key ----
//  ------------------
public func pem2key(filePath: String) throws -> P521.Signing.PrivateKey {

    let pemURL: URL = URL(filePath: filePath)

    return try pem2key(filePem: pemURL)
}

public func pem2key(filePem: URL) throws -> P521.Signing.PrivateKey {

    let fileString: String = try String(contentsOf: filePem, encoding: String.Encoding.utf8)
    return try pem2key(pemString: fileString)
}

public func pem2key(pemString: String) throws -> P521.Signing.PrivateKey {
    return try P521.Signing.PrivateKey(pemRepresentation: pemString)
}