package cli_test

import (
	"bytes"
	"strings"
	"testing"

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

// The two lines the README says the example mnemonic produces.
const (
	vectorZero = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIJZOtOczrc/7CQytc" +
		"uFwt7s4r8KjkZWkwjLZWBaFKD+7"
	vectorOne = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIOEWY8+/gmHYVC4u0Y" +
		"0I4FKs+eVUulTPHfk9VtXw1tMF"
)

// example returns the mnemonic the README gives its test vectors for:
// eleven abandons and about.
func example() string {
	return strings.Repeat("abandon ", 11) + "about"
}

func TestTheReadmeTestVectors(t *testing.T) {
	t.Setenv(mnemonic.Variable, example())

	require.Equal(t,
		vectorZero+" keyfunc/ssh/0",
		strings.TrimSpace(run(t, "ssh", "pub", "-n", "0")),
	)
	require.Equal(t,
		vectorOne+" keyfunc/ssh/1",
		strings.TrimSpace(run(t, "ssh", "pub", "-n", "1")),
	)
}

func TestTheCommentCanBeChosen(t *testing.T) {
	t.Setenv(mnemonic.Variable, example())

	line := strings.TrimSpace(run(t, "ssh", "pub", "--comment", "mine"))
	require.Equal(t, vectorZero+" mine", line)
}

func TestThePrivateKeyMatchesThePublicOne(t *testing.T) {
	t.Setenv(mnemonic.Variable, example())

	block := run(t, "ssh", "priv", "-n", "1")
	require.True(t,
		strings.HasPrefix(block, "-----BEGIN OPENSSH PRIVATE KEY-----"),
	)

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

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

func TestTheMnemonicCommandIsUsed(t *testing.T) {
	t.Setenv(mnemonic.Variable, "")

	line := strings.TrimSpace(run(t,
		"ssh", "pub",
		"--mnemonic-command", "printf '%s\\n' '"+example()+"'",
	))
	require.Equal(t, vectorZero+" keyfunc/ssh/0", line)
}

// run executes the tool with the given arguments and returns what it
// wrote to standard output.
func run(t *testing.T, args ...string) string {
	t.Helper()

	var out bytes.Buffer

	root := cli.Root()
	root.SetOut(&out)
	root.SetErr(&out)
	root.SetArgs(args)

	require.NoError(t, root.ExecuteContext(t.Context()))

	return out.String()
}