package xssh

import (
	cryptorand "crypto/rand"
	"crypto/rsa"
	"crypto/x509"
	"encoding/pem"
	"golang.org/x/crypto/ssh"
)

func GenerateKey(bits int) (*rsa.PrivateKey, *rsa.PublicKey, error) {
	private, err := rsa.GenerateKey(cryptorand.Reader, bits)
	if err != nil {
		return nil, nil, err
	}
	return private, &private.PublicKey, nil

}

func EncodePrivateKey(private *rsa.PrivateKey) []byte {
	return pem.EncodeToMemory(&pem.Block{
		Bytes: x509.MarshalPKCS1PrivateKey(private),
		Type:  "RSA PRIVATE KEY",
	})
}

func EncodePublicKey(public interface{}) ([]byte, error) {
	publicBytes, err := x509.MarshalPKIXPublicKey(public)
	if err != nil {
		return nil, err
	}
	return pem.EncodeToMemory(&pem.Block{
		Bytes: publicBytes,
		Type:  "PUBLIC KEY",
	}), nil
}

// EncodeSSHKey

func EncodeSSHKey(public *rsa.PublicKey) ([]byte, error) {
	publicKey, err := ssh.NewPublicKey(public)
	if err != nil {
		return nil, err
	}
	return ssh.MarshalAuthorizedKey(publicKey), nil
}

//ssh-keygen  -N ''  -b 4096 -f filename

func MakeSSHKeyPair() (string, string, error) {
	pkey, pubkey, err := GenerateKey(2048)
	if err != nil {
		return "", "", err
	}

	pub, err := EncodeSSHKey(pubkey)
	if err != nil {
		return "", "", err
	}
	return string(EncodePrivateKey(pkey)), string(pub), nil
}