package keyer import ( "context" "github.com/nbd-wtf/go-nostr" "github.com/nbd-wtf/go-nostr/nip44" "github.com/puzpuzpuz/xsync/v3" ) // Keysigner is a signer that holds the private key in memory and can do all the operations instantly and easily. type KeySigner struct { sk string pk string conversationKeys *xsync.MapOf[string, [32]byte] } func NewPlainKeySigner(sec string) (KeySigner, error) { pk, err := nostr.GetPublicKey(sec) if err != nil { return KeySigner{}, err } return KeySigner{sec, pk, xsync.NewMapOf[string, [32]byte]()}, nil } func (ks KeySigner) SignEvent(ctx context.Context, evt *nostr.Event) error { return evt.Sign(ks.sk) } func (ks KeySigner) GetPublicKey(ctx context.Context) (string, error) { return ks.pk, nil } func (ks KeySigner) Encrypt(ctx context.Context, plaintext string, recipient string) (string, error) { ck, ok := ks.conversationKeys.Load(recipient) if !ok { var err error ck, err = nip44.GenerateConversationKey(recipient, ks.sk) if err != nil { return "", err } ks.conversationKeys.Store(recipient, ck) } return nip44.Encrypt(plaintext, ck) } func (ks KeySigner) Decrypt(ctx context.Context, base64ciphertext string, sender string) (string, error) { ck, ok := ks.conversationKeys.Load(sender) if !ok { var err error ck, err = nip44.GenerateConversationKey(sender, ks.sk) if err != nil { return "", err } ks.conversationKeys.Store(sender, ck) } return nip44.Decrypt(base64ciphertext, ck) }