func saveHost(store persist.Store, h *host.Host) error {
	if err := store.Save(h); err != nil {
		return fmt.Errorf("Error attempting to save host to store: %s", err)
	}

	return nil
}

func getInfoForScpArg(hostAndPath string, store persist.Store) (*host.Host, string, []string, error) {
	// TODO: What to do about colon in filepath?
	splitInfo := strings.Split(hostAndPath, ":")

	// Host path.  e.g. "/tmp/foo"
	if len(splitInfo) == 1 {
		return nil, splitInfo[0], nil, nil
	}

	// Remote path.  e.g. "machinename:/usr/bin/cmatrix"
	if len(splitInfo) == 2 {
		path := splitInfo[1]
		host, err := store.Load(splitInfo[0])
		if err != nil {
			return nil, "", nil, fmt.Errorf("Error loading host: %s", err)
		}
		args := []string{
			"-i",
			host.Driver.GetSSHKeyPath(),
		}
		return host, path, args, nil
	}

	return nil, "", nil, ErrMalformedInput
}

// Create is the wrapper method which covers all of the boilerplate around
// actually creating, provisioning, and persisting an instance in the store.
func create(store persist.Store, h *host.Host, callback func(*host.Host)) error {
	if err := cert.BootstrapCertificates(h.HostOptions.AuthOptions); err != nil {
		return fmt.Errorf("Error generating certificates: %s", err)
	}

	log.Info("Running pre-create checks...")

	if err := h.Driver.PreCreateCheck(); err != nil {
		return fmt.Errorf("Error with pre-create check: %s", err)
	}

	if err := store.Save(h); err != nil {
		return fmt.Errorf("Error saving host to store before attempting creation: %s", err)
	}

	log.Info("Creating machine...")

	if err := h.Driver.Create(); err != nil {
		return fmt.Errorf("Error in driver during machine creation: %s", err)
	}

	if err := store.Save(h); err != nil {
		return fmt.Errorf("Error saving host to store after attempting creation: %s", err)
	}

	// TODO: Not really a fan of just checking "none" here.
	if h.Driver.DriverName() != "none" {
		log.Info("Waiting for machine to be running, this may take a few minutes...")
		if err := mcnutils.WaitFor(drivers.MachineInState(h.Driver, state.Running)); err != nil {
			return fmt.Errorf("Error waiting for machine to be running: %s", err)
		}

		log.Info("Machine is running, waiting for SSH to be available...")
		if err := drivers.WaitForSSH(h.Driver); err != nil {
			return fmt.Errorf("Error waiting for SSH: %s", err)
		}

		log.Info("Detecting operating system of created instance...")
		provisioner, err := provision.DetectProvisioner(h.Driver)
		if err != nil {
			return fmt.Errorf("Error detecting OS: %s", err)
		}

		callback(h)

		log.Info("Provisioning created instance...")
		if err := provisioner.Provision(*h.HostOptions.SwarmOptions, *h.HostOptions.AuthOptions, *h.HostOptions.EngineOptions); err != nil {
			return fmt.Errorf("Error running provisioning: %s", err)
		}
	}

	log.Debug("Reticulating splines...")

	return nil
}

func loadHost(store persist.Store, hostName string) (*host.Host, error) {
	h, err := store.Load(hostName)
	if err != nil {
		return nil, fmt.Errorf("Loading host from store failed: %s", err)
	}

	d, err := newPluginDriver(h.DriverName, h.RawDriver)
	if err != nil {
		return nil, fmt.Errorf("Error attempting to invoke binary for plugin: %s", err)
	}

	h.Driver = d

	return h, nil
}

func listHosts(store persist.Store, storePath string) ([]*host.Host, error) {
	cliHosts := []*host.Host{}

	hosts, err := store.List()
	if err != nil {
		return nil, fmt.Errorf("Error attempting to list hosts from store: %s", err)
	}

	for _, h := range hosts {
		h, err = loadHost(store, h.Name, storePath)
		if err != nil {
			return nil, err
		}
		cliHosts = append(cliHosts, h)
	}

	return cliHosts, nil
}

func loadHost(store persist.Store, hostName string, storePath string) (*host.Host, error) {
	h, err := store.Load(hostName)
	if err != nil {
		return nil, fmt.Errorf("Loading host from store failed: %s", err)
	}

	d, err := driverfactory.NewDriver(h.DriverName, h.Name, storePath)
	if err != nil {
		return nil, err
	}

	err = json.Unmarshal(h.RawDriver, &d)
	if err != nil {
		return nil, err
	}
	h.Driver = d

	return h, nil
}

func getActiveHost(store persist.Store) (*host.Host, error) {
	hosts, err := store.List()
	if err != nil {
		return nil, err
	}

	hostListItems := getHostListItems(hosts)

	for _, item := range hostListItems {
		if item.Active {
			h, err := store.Load(item.Name)
			if err != nil {
				return nil, err
			}
			return h, nil
		}
	}

	return nil, errors.New("Active host not found")
}

func listHosts(store persist.Store) ([]*host.Host, error) {
	cliHosts := []*host.Host{}

	hosts, err := store.List()
	if err != nil {
		return nil, fmt.Errorf("Error attempting to list hosts from store: %s", err)
	}

	for _, h := range hosts {
		d, err := newPluginDriver(h.DriverName, h.RawDriver)
		if err != nil {
			return nil, fmt.Errorf("Error attempting to invoke binary for plugin '%s': %s", h.DriverName, err)
		}

		h.Driver = d

		cliHosts = append(cliHosts, h)
	}

	return cliHosts, nil
}