package platform

import (
	"context"
	"os/exec"
	"strings"
)

// ListWSLDistros 返回本机已安装的 WSL 发行版；未安装 WSL 时返回稳定错误码。
func ListWSLDistros(ctx context.Context) ([]string, error) {
	if _, e := exec.LookPath("wsl.exe"); e != nil {
		return nil, &PlatformError{Code: "WSL_NOT_INSTALLED", Detail: e.Error()}
	}
	out, e := RunHidden(ctx, "wsl.exe", "--list", "--quiet")
	if e != nil {
		return nil, &PlatformError{Code: "WSL_LIST_FAILED", Detail: e.Error()}
	}
	items := []string{}
	for _, v := range strings.FieldsFunc(out, func(r rune) bool { return r == '\r' || r == '\n' || r == 0 }) {
		v = strings.TrimSpace(v)
		if v != "" {
			items = append(items, v)
		}
	}
	return items, nil
}

type PlatformError struct{ Code, Detail string }

func (e *PlatformError) Error() string {
	if e.Detail == "" {
		return e.Code
	}
	return e.Code + ": " + e.Detail
}