const (
	// DefaultAuthKey is the key used for dockerhub in config files, which
	// is hardcoded for historical reasons.
	DefaultAuthKey = "https://" + name.DefaultRegistry + "/v1/"
)

type AuthConfig struct {
	Username string `json:"username,omitempty"`
	Password string `json:"password,omitempty"`
	Auth     string `json:"auth,omitempty"`

	// IdentityToken is used to authenticate the user and get
	// an access token for the registry.
	IdentityToken string `json:"identitytoken,omitempty"`

	// RegistryToken is a bearer token to be sent to a registry
	RegistryToken string `json:"registrytoken,omitempty"`
}

type Authenticator interface {
	// Authorization returns the value to use in an http transport's Authorization header.
	Authorization() (*AuthConfig, error)
}

var Anonymous Authenticator = &anonymous{}

type Basic struct {
	Username string
	Password string
}

type Bearer struct {
	Token string `json:"token"`
}

type Keychain interface {
	// Resolve looks up the most appropriate credential for the specified target.
	Resolve(Resource) (Authenticator, error)
}

var (
	// DefaultKeychain implements Keychain by interpreting the docker config file.
	DefaultKeychain Keychain = &defaultKeychain{}
)

type Resource interface {
	// String returns the full string representation of the target, e.g.
	// gcr.io/my-project or just gcr.io.
	String() string

	// RegistryStr returns just the registry portion of the target, e.g. for
	// gcr.io/my-project, this should just return gcr.io. This is needed to
	// pull out an appropriate hostname.
	RegistryStr() string
}