package ssh

import (
	"github.com/google/uuid"
	"golang.org/x/crypto/ssh"
)

const userIDKey = "user_id"
const userHandleKey = "user_handle"
const isAnonymousKey = "is_anonymous"

func AuthenticatePublicKey(store Store, conn ssh.ConnMetadata, key ssh.PublicKey) (*ssh.Permissions, error) {
	fingerprint := ssh.FingerprintSHA256(key)
	user, err := store.UserByFingerprint(fingerprint)

	if err != nil || user.ID == uuid.Nil {
		return &ssh.Permissions{
			Extensions: map[string]string{
				isAnonymousKey: "true",
			},
		}, nil // no error = goes through
	}

	return &ssh.Permissions{
		Extensions: map[string]string{
			userIDKey:     user.ID.String(),
			userHandleKey: user.Handle,
		},
	}, nil // no error = goes through
}