package version

import (
	"os"
	"path/filepath"
	"testing"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

func TestReplaceAndRestoreUpdateFileKeepRecoverableBackup(t *testing.T) {
	directory := t.TempDir()
	target := filepath.Join(directory, "manager")
	replacement := filepath.Join(directory, "manager.new")
	backup := filepath.Join(directory, "manager.backup")
	require.NoError(t, os.WriteFile(target, []byte("known-good"), 0o755))
	require.NoError(t, os.WriteFile(replacement, []byte("candidate"), 0o755))

	require.NoError(t, replaceUpdateFile(target, replacement, backup))
	content, err := os.ReadFile(target)
	require.NoError(t, err)
	assert.Equal(t, "candidate", string(content))
	content, err = os.ReadFile(backup)
	require.NoError(t, err)
	assert.Equal(t, "known-good", string(content))

	require.NoError(t, restoreUpdateFile(target, backup))
	content, err = os.ReadFile(target)
	require.NoError(t, err)
	assert.Equal(t, "known-good", string(content))
	assert.NoFileExists(t, backup)
}

func TestRollbackAppliedTargetRequiresBackup(t *testing.T) {
	directory := t.TempDir()
	targetPath := filepath.Join(directory, "manager")
	require.NoError(t, os.WriteFile(targetPath, []byte("candidate"), 0o755))
	journal := &UpdateJournal{Targets: []UpdateTarget{{
		Role: "primary", Path: targetPath, BackupPath: filepath.Join(directory, "missing.backup"), Applied: true,
	}}}

	err := rollbackUpdateTargets(journal)
	require.Error(t, err)
	assert.Contains(t, err.Error(), "required primary backup unavailable")
	assert.Equal(t, "rollback_failed", journal.Targets[0].Outcome)
	content, readErr := os.ReadFile(targetPath)
	require.NoError(t, readErr)
	assert.Equal(t, "candidate", string(content), "failed rollback must not remove the remaining executable")
}

func TestUpdateHelperCommandPreservesTerminalDescriptors(t *testing.T) {
	cmd := newUpdateHelperCommand("manager-helper", "transaction.json")
	assert.Same(t, os.Stdin, cmd.Stdin)
	assert.Same(t, os.Stdout, cmd.Stdout)
	assert.Same(t, os.Stderr, cmd.Stderr)
	assert.Equal(t, []string{"manager-helper", "--update-helper=transaction.json"}, cmd.Args)

	relaunch := newRelaunchedTUICommand("manager", "transaction.json", true)
	assert.Same(t, os.Stdin, relaunch.Stdin)
	assert.Same(t, os.Stdout, relaunch.Stdout)
	assert.Same(t, os.Stderr, relaunch.Stderr)
	assert.Equal(t, []string{"manager", "--post-update=transaction.json", "--post-update-restart=tui"}, relaunch.Args)
}