package provision

import (
	"bytes"
	"encoding/json"
	"fmt"
	"net"
	"path"
	"text/template"
	"time"

	"github.com/docker/machine/commands/mcndirs"
	"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/state"
	"github.com/docker/machine/libmachine/swarm"
)

func init() {
	Register("boot2docker", &RegisteredProvisioner{
		New: NewBoot2DockerProvisioner,
	})
}

func NewBoot2DockerProvisioner(d drivers.Driver) Provisioner {
	return &Boot2DockerProvisioner{
		Driver: d,
	}
}

type Boot2DockerProvisioner struct {
	OsReleaseInfo *OsRelease
	Driver        drivers.Driver
	AuthOptions   auth.Options
	EngineOptions engine.Options
	SwarmOptions  swarm.Options
}

func (provisioner *Boot2DockerProvisioner) String() string {
	return "boot2docker"
}

func (provisioner *Boot2DockerProvisioner) Service(name string, action serviceaction.ServiceAction) error {
	_, err := provisioner.SSHCommand(fmt.Sprintf("sudo /etc/init.d/%s %s", name, action.String()))
	return err
}

func (provisioner *Boot2DockerProvisioner) upgradeIso() error {
	// TODO: Ideally, we should not read from mcndirs directory at all.
	// The driver should be able to communicate how and where to place the
	// relevant files.
	b2dutils := mcnutils.NewB2dUtils(mcndirs.GetBaseDir())

	// Check if the driver has specified a custom b2d url
	jsonDriver, err := json.Marshal(provisioner.GetDriver())
	if err != nil {
		return err
	}
	var d struct {
		Boot2DockerURL string
	}
	json.Unmarshal(jsonDriver, &d)

	log.Info("Stopping machine to do the upgrade...")

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

	if err := mcnutils.WaitFor(drivers.MachineInState(provisioner.Driver, state.Stopped)); err != nil {
		return err
	}

	machineName := provisioner.GetDriver().GetMachineName()

	log.Infof("Upgrading machine %q...", machineName)

	// Either download the latest version of the b2d url that was explicitly
	// specified when creating the VM or copy the (updated) default ISO
	if err := b2dutils.CopyIsoToMachineDir(d.Boot2DockerURL, machineName); err != nil {
		return err
	}

	log.Infof("Starting machine back up...")

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

	return mcnutils.WaitFor(drivers.MachineInState(provisioner.Driver, state.Running))
}

func (provisioner *Boot2DockerProvisioner) Package(name string, action pkgaction.PackageAction) error {
	if name == "docker" && action == pkgaction.Upgrade {
		if err := provisioner.upgradeIso(); err != nil {
			return err
		}
	}
	return nil
}

func (provisioner *Boot2DockerProvisioner) Hostname() (string, error) {
	return provisioner.SSHCommand("hostname")
}

func (provisioner *Boot2DockerProvisioner) SetHostname(hostname string) error {
	if _, err := provisioner.SSHCommand(fmt.Sprintf(
		"sudo /usr/bin/sethostname %s && echo %q | sudo tee /var/lib/boot2docker/etc/hostname",
		hostname,
		hostname,
	)); err != nil {
		return err
	}

	return nil
}

func (provisioner *Boot2DockerProvisioner) GetDockerOptionsDir() string {
	return "/var/lib/boot2docker"
}

func (provisioner *Boot2DockerProvisioner) GetAuthOptions() auth.Options {
	return provisioner.AuthOptions
}

func (provisioner *Boot2DockerProvisioner) GenerateDockerOptions(dockerPort int) (*DockerOptions, error) {
	var (
		engineCfg bytes.Buffer
	)

	driverNameLabel := fmt.Sprintf("provider=%s", provisioner.Driver.DriverName())
	provisioner.EngineOptions.Labels = append(provisioner.EngineOptions.Labels, driverNameLabel)

	engineConfigTmpl := `
EXTRA_ARGS='
{{ range .EngineOptions.Labels }}--label {{.}}
{{ end }}{{ range .EngineOptions.InsecureRegistry }}--insecure-registry {{.}}
{{ end }}{{ range .EngineOptions.RegistryMirror }}--registry-mirror {{.}}
{{ end }}{{ range .EngineOptions.ArbitraryFlags }}--{{.}}
{{ end }}
'
CACERT={{.AuthOptions.CaCertRemotePath}}
DOCKER_HOST='-H tcp://0.0.0.0:{{.DockerPort}}'
DOCKER_STORAGE={{.EngineOptions.StorageDriver}}
DOCKER_TLS=auto
SERVERKEY={{.AuthOptions.ServerKeyRemotePath}}
SERVERCERT={{.AuthOptions.ServerCertRemotePath}}

{{range .EngineOptions.Env}}export \"{{ printf "%q" . }}\"
{{end}}
`
	t, err := template.New("engineConfig").Parse(engineConfigTmpl)
	if err != nil {
		return nil, err
	}

	engineConfigContext := EngineConfigContext{
		DockerPort:    dockerPort,
		AuthOptions:   provisioner.AuthOptions,
		EngineOptions: provisioner.EngineOptions,
	}

	t.Execute(&engineCfg, engineConfigContext)

	daemonOptsDir := path.Join(provisioner.GetDockerOptionsDir(), "profile")
	return &DockerOptions{
		EngineOptions:     engineCfg.String(),
		EngineOptionsPath: daemonOptsDir,
	}, nil
}

func (provisioner *Boot2DockerProvisioner) CompatibleWithHost() bool {
	return provisioner.OsReleaseInfo.ID == "boot2docker"
}

func (provisioner *Boot2DockerProvisioner) SetOsReleaseInfo(info *OsRelease) {
	provisioner.OsReleaseInfo = info
}

func (provisioner *Boot2DockerProvisioner) GetOsReleaseInfo() (*OsRelease, error) {
	return provisioner.OsReleaseInfo, nil
}

func (provisioner *Boot2DockerProvisioner) AttemptIPContact(dockerPort int) {
	ip, err := provisioner.Driver.GetIP()
	if err != nil {
		log.Warnf("Could not get IP address for created machine: %s", err)
		return
	}

	if conn, err := net.DialTimeout("tcp", fmt.Sprintf("%s:%d", ip, dockerPort), 5*time.Second); err != nil {
		log.Warn(`
This machine has been allocated an IP address, but Docker Machine could not
reach it successfully.

SSH for the machine should still work, but connecting to exposed ports, such as
the Docker daemon port (usually <ip>:2376), may not work properly.

You may need to add the route manually, or use another related workaround.

This could be due to a VPN, proxy, or host file configuration issue.

You also might want to clear any VirtualBox host only interfaces you are not using.`)
	} else {
		conn.Close()
	}
}

func (provisioner *Boot2DockerProvisioner) Provision(swarmOptions swarm.Options, authOptions auth.Options, engineOptions engine.Options) error {
	const (
		dockerPort = 2376
	)

	var (
		err error
	)

	defer func() {
		if err == nil {
			provisioner.AttemptIPContact(dockerPort)
		}
	}()

	provisioner.SwarmOptions = swarmOptions
	provisioner.AuthOptions = authOptions
	provisioner.EngineOptions = engineOptions
	swarmOptions.Env = engineOptions.Env

	if provisioner.EngineOptions.StorageDriver == "" {
		provisioner.EngineOptions.StorageDriver = "aufs"
	}

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

	// b2d hosts need to wait for the daemon to be up
	// before continuing with provisioning
	if err = waitForDocker(provisioner, dockerPort); err != nil {
		return err
	}

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

	provisioner.AuthOptions = setRemoteAuthOptions(provisioner)

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

	if err = configureSwarm(provisioner, swarmOptions, provisioner.AuthOptions); err != nil {
		return err
	}

	return nil
}

func (provisioner *Boot2DockerProvisioner) SSHCommand(args string) (string, error) {
	return drivers.RunSSHCommandFromDriver(provisioner.Driver, args)
}

func (provisioner *Boot2DockerProvisioner) GetDriver() drivers.Driver {
	return provisioner.Driver
}