// ComposeUserData fills out the provided cloudinit configuration structure
// so it is suitable for initialising a machine with the given configuration,
// and then renders it and encodes it using the supplied renderer.
// When calling ComposeUserData a encoding implementation must be chosen from
// the providerinit/encoders package according to the need of the provider.
//
// If the provided cloudcfg is nil, a new one will be created internally.
func ComposeUserData(icfg *instancecfg.InstanceConfig, cloudcfg cloudinit.CloudConfig, renderer renderers.ProviderRenderer) ([]byte, error) {
	if cloudcfg == nil {
		var err error
		cloudcfg, err = cloudinit.New(icfg.Series)
		if err != nil {
			return nil, errors.Trace(err)
		}
	}
	_, err := configureCloudinit(icfg, cloudcfg)
	if err != nil {
		return nil, errors.Trace(err)
	}
	operatingSystem, err := series.GetOSFromSeries(icfg.Series)
	if err != nil {
		return nil, errors.Trace(err)
	}
	// This might get replaced by a renderer.RenderUserdata which will either
	// render it as YAML or Bash since some CentOS images might ship without cloudnit
	udata, err := cloudcfg.RenderYAML()
	if err != nil {
		return nil, errors.Trace(err)
	}
	udata, err = renderer.EncodeUserdata(udata, operatingSystem)
	if err != nil {
		return nil, errors.Trace(err)
	}
	logger.Tracef("Generated cloud init:\n%s", string(udata))
	return udata, err
}

func assertScriptMatches(c *gc.C, cfg cloudinit.CloudConfig, pattern string, match bool) {
	script, err := cfg.RenderScript()
	c.Assert(err, jc.ErrorIsNil)
	checker := gc.Matches
	if !match {
		checker = gc.Not(checker)
	}
	c.Assert(script, checker, pattern)
}

// cloudinitRunCmd returns the shell command that, when run, will create the
// "machine info" file containing the hostname of a machine.
// That command is destined to be used by cloudinit.
func (info *machineInfo) cloudinitRunCmd(cloudcfg cloudinit.CloudConfig) (string, error) {
	dataDir, err := paths.DataDir(cloudcfg.GetSeries())
	if err != nil {
		return "", errors.Trace(err)
	}
	yaml, err := goyaml.Marshal(info)
	if err != nil {
		return "", errors.Trace(err)
	}
	renderer := cloudcfg.ShellRenderer()
	fileName := renderer.Join(renderer.FromSlash(dataDir), "MAASmachine.txt")
	script := renderer.MkdirAll(dataDir)
	contents := renderer.Quote(string(yaml))
	script = append(script, renderer.WriteFile(fileName, []byte(contents))...)
	script = append(script, renderer.Chmod(fileName, 0755)...)
	return strings.Join(script, "\n"), nil
}

// ComposeUserData fills out the provided cloudinit configuration structure
// so it is suitable for initialising a machine with the given configuration,
// and then renders it and returns it as a binary (gzipped) blob of user data.
//
// If the provided cloudcfg is nil, a new one will be created internally.
func ComposeUserData(icfg *instancecfg.InstanceConfig, cloudcfg cloudinit.CloudConfig) ([]byte, error) {
	if cloudcfg == nil {
		var err error
		cloudcfg, err = cloudinit.New(icfg.Series)
		if err != nil {
			return nil, err
		}
	}
	_, err := configureCloudinit(icfg, cloudcfg)
	if err != nil {
		return nil, err
	}
	data, err := cloudcfg.RenderYAML()
	logger.Tracef("Generated cloud init:\n%s", string(data))
	if err != nil {
		return nil, err
	}
	return utils.Gzip(data), nil
}

func assertUserData(c *gc.C, cloudConf cloudinit.CloudConfig, expected string) {
	data, err := cloudConf.RenderYAML()
	c.Assert(err, jc.ErrorIsNil)
	c.Assert(string(data), gc.Equals, expected)
	// Make sure it's valid YAML as well.
	out := make(map[string]interface{})
	err = yaml.Unmarshal(data, &out)
	c.Assert(err, jc.ErrorIsNil)
	if len(cloudConf.BootCmds()) > 0 {
		outcmds := out["bootcmd"].([]interface{})
		confcmds := cloudConf.BootCmds()
		c.Assert(len(outcmds), gc.Equals, len(confcmds))
		for i, _ := range outcmds {
			c.Assert(outcmds[i].(string), gc.Equals, confcmds[i])
		}
	} else {
		c.Assert(out["bootcmd"], gc.IsNil)
	}
}

// SetUbuntuUser creates an "ubuntu" use for unix systems so the juju client
// can access the machine using ssh with the configuration we expect.
// On precise, the default cloudinit version is too old to support the users
// option, so instead rely on the default user being created and adding keys.
// It may make sense in the future to add a "juju" user instead across
// all distributions.
func SetUbuntuUser(conf cloudinit.CloudConfig, authorizedKeys string) {
	targetSeries := conf.GetSeries()
	if targetSeries == "precise" {
		conf.SetSSHAuthorizedKeys(authorizedKeys)
	} else {
		var groups []string
		targetOS, _ := series.GetOSFromSeries(targetSeries)
		switch targetOS {
		case os.Ubuntu:
			groups = UbuntuGroups
		case os.CentOS:
			groups = CentOSGroups
		}
		conf.AddUser(&cloudinit.User{
			Name:              "ubuntu",
			Groups:            groups,
			Shell:             "/bin/bash",
			Sudo:              []string{"ALL=(ALL) NOPASSWD:ALL"},
			SSHAuthorizedKeys: authorizedKeys,
		})
	}
}

// TemplateUserData returns a minimal user data necessary for the template.
// This should have the authorized keys, base packages, the cloud archive if
// necessary,  initial apt proxy config, and it should do the apt-get
// update/upgrade initially.
func TemplateUserData(
	series string,
	authorizedKeys string,
	aptProxy proxy.Settings,
	aptMirror string,
	enablePackageUpdates bool,
	enableOSUpgrades bool,
	networkConfig *container.NetworkConfig,
) ([]byte, error) {
	var config cloudinit.CloudConfig
	var err error
	if networkConfig != nil {
		config, err = newCloudInitConfigWithNetworks(series, networkConfig)
		if err != nil {
			return nil, errors.Trace(err)
		}
	} else {
		config, err = cloudinit.New(series)
		if err != nil {
			return nil, errors.Trace(err)
		}
	}
	cloudconfig.SetUbuntuUser(config, authorizedKeys)
	config.AddScripts(
		"set -xe", // ensure we run all the scripts or abort.
	)
	// For LTS series which need support for the cloud-tools archive,
	// we need to enable apt-get update regardless of the environ
	// setting, otherwise provisioning will fail.
	if series == "precise" && !enablePackageUpdates {
		logger.Warningf("series %q requires cloud-tools archive: enabling updates", series)
		enablePackageUpdates = true
	}

	if enablePackageUpdates && config.RequiresCloudArchiveCloudTools() {
		config.AddCloudArchiveCloudTools()
	}
	config.AddPackageCommands(aptProxy, aptMirror, enablePackageUpdates, enableOSUpgrades)

	initSystem, err := service.VersionInitSystem(series)
	if err != nil {
		return nil, errors.Trace(err)
	}
	cmds, err := shutdownInitCommands(initSystem, series)
	if err != nil {
		return nil, errors.Trace(err)
	}
	config.AddScripts(strings.Join(cmds, "\n"))

	data, err := config.RenderYAML()
	if err != nil {
		return nil, err
	}
	return data, nil
}