package sshkey_test

import (
	"strings"
	"testing"

	"git.eeqj.de/sneak/keyfunc/internal/derive"
	"git.eeqj.de/sneak/keyfunc/internal/sshkey"
	"github.com/stretchr/testify/require"
	"golang.org/x/crypto/ssh"
)

// example returns the mnemonic every BIP-39 document uses to show its
// test vectors: eleven abandons and about.
func example() string {
	return strings.Repeat("abandon ", 11) + "about"
}

func TestTooFewBytesAreRefused(t *testing.T) {
	t.Parallel()

	_, err := sshkey.New([]byte("short"))
	require.ErrorIs(t, err, sshkey.ErrSize)
}

func TestTheCommentIsPutAtTheEndOfTheLine(t *testing.T) {
	t.Parallel()

	key := forIndex(t, 0)

	line, err := key.Line("hello")
	require.NoError(t, err)
	require.True(t, strings.HasPrefix(line, "ssh-ed25519 "))
	require.True(t, strings.HasSuffix(line, " hello"))
}

func TestThePrivateKeyCarriesTheSamePublicKey(t *testing.T) {
	t.Parallel()

	key := forIndex(t, 0)

	line, err := key.Line("")
	require.NoError(t, err)

	block, err := key.Block("a comment")
	require.NoError(t, err)

	parsed, err := ssh.ParsePrivateKey([]byte(block))
	require.NoError(t, err)

	back := strings.TrimSpace(
		string(ssh.MarshalAuthorizedKey(parsed.PublicKey())),
	)
	require.Equal(t, line, back)
}

// forIndex derives the key for one index.
func forIndex(t *testing.T, index uint32) *sshkey.Key {
	t.Helper()

	material, err := derive.Bytes(example(), sshkey.Application, index)
	require.NoError(t, err)

	key, err := sshkey.New(material)
	require.NoError(t, err)

	return key
}