//go:build windows

package files

import (
	"context"
	"fmt"
	"os/exec"
	"path/filepath"
	"strings"
)

var ErrSelectionCanceled = context.Canceled

type commandRunner interface {
	Run(context.Context, string, ...string) ([]byte, error)
}

type execRunner struct{}

func (execRunner) Run(ctx context.Context, name string, args ...string) ([]byte, error) {
	return exec.CommandContext(ctx, name, args...).Output()
}

type windowsDirectoryPicker struct{ runner commandRunner }

func NewDirectoryPicker() DirectoryPicker { return windowsDirectoryPicker{runner: execRunner{}} }

func newDirectoryPickerWithRunner(runner commandRunner) windowsDirectoryPicker {
	return windowsDirectoryPicker{runner: runner}
}

func (p windowsDirectoryPicker) ChooseDirectory(ctx context.Context) (string, error) {
	if err := ctx.Err(); err != nil {
		return "", err
	}
	output, err := p.runner.Run(ctx, "powershell.exe",
		"-NoProfile", "-NonInteractive", "-STA", "-WindowStyle", "Hidden", "-Command", folderDialogScript)
	if err != nil {
		if ctxErr := ctx.Err(); ctxErr != nil {
			return "", ctxErr
		}
		return "", fmt.Errorf("open directory picker: %w", err)
	}
	selected := strings.TrimSpace(string(output))
	if selected == "" {
		return "", ErrSelectionCanceled
	}
	if !filepath.IsAbs(selected) {
		return "", fmt.Errorf("directory picker returned a non-absolute path")
	}
	return filepath.Clean(selected), nil
}

const folderDialogScript = `[Console]::OutputEncoding = [System.Text.UTF8Encoding]::new($false)
Add-Type -AssemblyName System.Windows.Forms
$dialog = New-Object System.Windows.Forms.FolderBrowserDialog
$dialog.Description = '选择浏览器 User Data Dir'
$dialog.ShowNewFolderButton = $true
if ($dialog.ShowDialog() -eq [System.Windows.Forms.DialogResult]::OK) {
  [Console]::Out.Write($dialog.SelectedPath)
}`