package provision

import (
	"fmt"
	"strconv"

	"github.com/docker/machine/libmachine/auth"
	"github.com/docker/machine/libmachine/drivers"
	"github.com/docker/machine/libmachine/engine"
	"github.com/docker/machine/libmachine/log"
	"github.com/docker/machine/libmachine/mcnutils"
	"github.com/docker/machine/libmachine/provision/pkgaction"
	"github.com/docker/machine/libmachine/provision/serviceaction"
	"github.com/docker/machine/libmachine/swarm"
)

func init() {
	Register("Ubuntu-UpStart", &RegisteredProvisioner{
		New: NewUbuntuProvisioner,
	})
}

func NewUbuntuProvisioner(d drivers.Driver) Provisioner {
	return &UbuntuProvisioner{
		GenericProvisioner{
			SSHCommander:      GenericSSHCommander{Driver: d},
			DockerOptionsDir:  "/etc/docker",
			DaemonOptionsFile: "/etc/default/docker",
			OsReleaseID:       "ubuntu",
			Packages: []string{
				"curl",
			},
			Driver: d,
		},
	}
}

type UbuntuProvisioner struct {
	GenericProvisioner
}

func (provisioner *UbuntuProvisioner) String() string {
	return "ubuntu(upstart)"
}

func (provisioner *UbuntuProvisioner) CompatibleWithHost() bool {
	const FirstUbuntuSystemdVersion = 15.04
	isUbuntu := provisioner.OsReleaseInfo.ID == provisioner.OsReleaseID
	if !isUbuntu {
		return false
	}
	versionNumber, err := strconv.ParseFloat(provisioner.OsReleaseInfo.VersionID, 64)
	if err != nil {
		return false
	}

	return versionNumber < FirstUbuntuSystemdVersion

}

func (provisioner *UbuntuProvisioner) Service(name string, action serviceaction.ServiceAction) error {
	command := fmt.Sprintf("sudo service %s %s", name, action.String())

	if _, err := provisioner.SSHCommand(command); err != nil {
		return err
	}

	return nil
}

func (provisioner *UbuntuProvisioner) Package(name string, action pkgaction.PackageAction) error {
	var packageAction string

	updateMetadata := true

	switch action {
	case pkgaction.Install, pkgaction.Upgrade:
		packageAction = "install"
	case pkgaction.Remove, pkgaction.Purge:
		packageAction = "remove"
		updateMetadata = false
	}

	switch name {
	case "docker":
		name = "docker-engine"
	}

	if updateMetadata {
		if err := waitForLockAptGetUpdate(provisioner); err != nil {
			return err
		}
	}

	command := fmt.Sprintf("DEBIAN_FRONTEND=noninteractive sudo -E apt-get %s -y -o Dpkg::Options::=\"--force-confnew\" %s", packageAction, name)

	log.Debugf("package: action=%s name=%s", action.String(), name)

	return waitForLock(provisioner, command)
}

func (provisioner *UbuntuProvisioner) dockerDaemonResponding() bool {
	log.Debug("checking docker daemon")

	if out, err := provisioner.SSHCommand("sudo docker version"); err != nil {
		log.Warnf("Error getting SSH command to check if the daemon is up: %s", err)
		log.Debugf("'sudo docker version' output:\n%s", out)
		return false
	}

	// The daemon is up if the command worked.  Carry on.
	return true
}

func (provisioner *UbuntuProvisioner) Provision(swarmOptions swarm.Options, authOptions auth.Options, engineOptions engine.Options) error {
	provisioner.SwarmOptions = swarmOptions
	provisioner.AuthOptions = authOptions
	provisioner.EngineOptions = engineOptions
	swarmOptions.Env = engineOptions.Env

	storageDriver, err := decideStorageDriver(provisioner, "aufs", engineOptions.StorageDriver)
	if err != nil {
		return err
	}
	provisioner.EngineOptions.StorageDriver = storageDriver

	if err := provisioner.SetHostname(provisioner.Driver.GetMachineName()); err != nil {
		return err
	}

	for _, pkg := range provisioner.Packages {
		if err := provisioner.Package(pkg, pkgaction.Install); err != nil {
			return err
		}
	}

	log.Info("Installing Docker...")
	if err := installDockerGeneric(provisioner, engineOptions.InstallURL); err != nil {
		return err
	}

	if err := mcnutils.WaitFor(provisioner.dockerDaemonResponding); err != nil {
		return err
	}

	if err := makeDockerOptionsDir(provisioner); err != nil {
		return err
	}

	provisioner.AuthOptions = setRemoteAuthOptions(provisioner)

	if err := ConfigureAuth(provisioner); err != nil {
		return err
	}

	err = configureSwarm(provisioner, swarmOptions, provisioner.AuthOptions)
	return err
}
