// AllModels allows controller administrators to get the list of all the
// environments in the controller.
func (s *ControllerAPI) AllModels() (params.UserModelList, error) {
	result := params.UserModelList{}
	if err := s.checkHasAdmin(); err != nil {
		return result, errors.Trace(err)
	}

	// Get all the environments that the authenticated user can see, and
	// supplement that with the other environments that exist that the user
	// cannot see. The reason we do this is to get the LastConnection time for
	// the environments that the user is able to see, so we have consistent
	// output when listing with or without --all when an admin user.
	environments, err := s.state.ModelsForUser(s.apiUser)
	if err != nil {
		return result, errors.Trace(err)
	}
	visibleEnvironments := set.NewStrings()
	for _, env := range environments {
		lastConn, err := env.LastConnection()
		if err != nil && !state.IsNeverConnectedError(err) {
			return result, errors.Trace(err)
		}
		visibleEnvironments.Add(env.UUID())
		result.UserModels = append(result.UserModels, params.UserModel{
			Model: params.Model{
				Name:     env.Name(),
				UUID:     env.UUID(),
				OwnerTag: env.Owner().String(),
			},
			LastConnection: &lastConn,
		})
	}

	allEnvs, err := s.state.AllModels()
	if err != nil {
		return result, errors.Trace(err)
	}

	for _, env := range allEnvs {
		if !visibleEnvironments.Contains(env.UUID()) {
			result.UserModels = append(result.UserModels, params.UserModel{
				Model: params.Model{
					Name:     env.Name(),
					UUID:     env.UUID(),
					OwnerTag: env.Owner().String(),
				},
				// No LastConnection as this user hasn't.
			})
		}
	}

	// Sort the resulting sequence by environment name, then owner.
	sort.Sort(orderedUserModels(result.UserModels))

	return result, nil
}

// ListModels returns the models that the specified user
// has access to in the current server.  Only that controller owner
// can list models for any user (at this stage).  Other users
// can only ask about their own models.
func (em *ModelManagerAPI) ListModels(user params.Entity) (params.UserModelList, error) {
	result := params.UserModelList{}

	userTag, err := names.ParseUserTag(user.Tag)
	if err != nil {
		return result, errors.Trace(err)
	}

	err = em.authCheck(userTag)
	if err != nil {
		return result, errors.Trace(err)
	}

	models, err := em.state.ModelsForUser(userTag)
	if err != nil {
		return result, errors.Trace(err)
	}

	for _, model := range models {
		var lastConn *time.Time
		userLastConn, err := model.LastConnection()
		if err != nil {
			if !state.IsNeverConnectedError(err) {
				return result, errors.Trace(err)
			}
		} else {
			lastConn = &userLastConn
		}
		result.UserModels = append(result.UserModels, params.UserModel{
			Model: params.Model{
				Name:     model.Name(),
				UUID:     model.UUID(),
				OwnerTag: model.Owner().String(),
			},
			LastConnection: lastConn,
		})
		logger.Debugf("list models: %s, %s, %s", model.Name(), model.UUID(), model.Owner())
	}

	return result, nil
}