package httpapi

import (

"regexp"

"strings"

"github.com/moby/moby/pkg/namesgenerator"

"golang.org/x/xerrors"

)

var (

UsernameValidRegex = regexp.MustCompile("^[a-zA-Z0-9]+(?:-[a-zA-Z0-9]+)*$")

usernameReplace = regexp.MustCompile("[^a-zA-Z0-9-]*")

templateDisplayName = regexp.MustCompile(`^[^\s](.*[^\s])?$`)

)

// UsernameFrom returns a best-effort username from the provided string.

//

// It first attempts to validate the incoming string, which will

// be returned if it is valid. It then will attempt to extract

// the username from an email address. If no success happens during

// these steps, a random username will be returned.

func UsernameFrom(str string) string {

if valid := NameValid(str); valid == nil {

return str

}

emailAt := strings.LastIndex(str, "@")

if emailAt >= 0 {

str = str[:emailAt]

}

str = usernameReplace.ReplaceAllString(str, "")

if valid := NameValid(str); valid == nil {

return str

}

return strings.ReplaceAll(namesgenerator.GetRandomName(1), "_", "-")

}

// NameValid returns whether the input string is a valid name.

// It is a generic validator for any name (user, workspace, template, etc.).

func NameValid(str string) error {

if len(str) > 32 {

return xerrors.New("must be <= 32 characters")

}

if len(str) < 1 {

return xerrors.New("must be >= 1 character")

}

matched := UsernameValidRegex.MatchString(str)

if !matched {

return xerrors.New("must be alphanumeric with hyphens")

}

return nil

}

// TemplateDisplayNameValid returns whether the input string is a valid template display name.

func TemplateDisplayNameValid(str string) error {

if len(str) == 0 {

return nil // empty display_name is correct

}

if len(str) > 64 {

return xerrors.New("must be <= 64 characters")

}

matched := templateDisplayName.MatchString(str)

if !matched {

return xerrors.New("must be alphanumeric with spaces")

}

return nil

}