// validateUploadAllowed returns an error if an attempt to upload tools should
// not be allowed.
func validateUploadAllowed(env environs.Environ, toolsArch, toolsSeries *string, validator constraints.Validator) error {
	// Now check that the architecture and series for which we are setting up an
	// environment matches that from which we are bootstrapping.
	hostArch := arch.HostArch()
	// We can't build tools for a different architecture if one is specified.
	if toolsArch != nil && *toolsArch != hostArch {
		return fmt.Errorf("cannot use agent built for %q using a machine running on %q", *toolsArch, hostArch)
	}
	hostOS := jujuos.HostOS()
	if toolsSeries != nil {
		toolsSeriesOS, err := series.GetOSFromSeries(*toolsSeries)
		if err != nil {
			return errors.Trace(err)
		}
		if !toolsSeriesOS.EquivalentTo(hostOS) {
			return errors.Errorf("cannot use agent built for %q using a machine running %q", *toolsSeries, hostOS)
		}
	}
	// If no architecture is specified, ensure the target provider supports instances matching our architecture.
	if _, err := validator.Validate(constraints.Value{Arch: &hostArch}); err != nil {
		return errors.Errorf(
			"model %q of type %s does not support instances running on %q",
			env.Config().Name(), env.Config().Type(), hostArch,
		)
	}
	return nil
}

func destroyStorage(env environs.Environ) error {
	logger.Infof("destroying storage")
	environConfig := env.Config()
	storageProviderTypes, ok := registry.EnvironStorageProviders(environConfig.Type())
	if !ok {
		return nil
	}
	for _, storageProviderType := range storageProviderTypes {
		storageProvider, err := registry.StorageProvider(storageProviderType)
		if err != nil {
			return errors.Trace(err)
		}
		if !storageProvider.Dynamic() {
			continue
		}
		if storageProvider.Scope() != storage.ScopeEnviron {
			continue
		}
		if err := destroyVolumes(environConfig, storageProviderType, storageProvider); err != nil {
			return errors.Trace(err)
		}
		// TODO(axw) destroy env-level filesystems when we have them.
	}
	return nil
}

// Bootstrap bootstraps the given environment. The supplied constraints are
// used to provision the instance, and are also set within the bootstrapped
// environment.
func Bootstrap(ctx environs.BootstrapContext, environ environs.Environ, args environs.BootstrapParams) error {
	cfg := environ.Config()
	network.InitializeFromConfig(cfg)
	if secret := cfg.AdminSecret(); secret == "" {
		return fmt.Errorf("environment configuration has no admin-secret")
	}
	if authKeys := ssh.SplitAuthorisedKeys(cfg.AuthorizedKeys()); len(authKeys) == 0 {
		// Apparently this can never happen, so it's not tested. But, one day,
		// Config will act differently (it's pretty crazy that, AFAICT, the
		// authorized-keys are optional config settings... but it's impossible
		// to actually *create* a config without them)... and when it does,
		// we'll be here to catch this problem early.
		return fmt.Errorf("environment configuration has no authorized-keys")
	}
	if _, hasCACert := cfg.CACert(); !hasCACert {
		return fmt.Errorf("environment configuration has no ca-cert")
	}
	if _, hasCAKey := cfg.CAPrivateKey(); !hasCAKey {
		return fmt.Errorf("environment configuration has no ca-private-key")
	}
	// Write out the bootstrap-init file, and confirm storage is writeable.
	if err := environs.VerifyStorage(environ.Storage()); err != nil {
		return err
	}
	logger.Debugf("environment %q supports service/machine networks: %v", environ.Name(), environ.SupportNetworks())
	logger.Infof("bootstrapping environment %q", environ.Name())
	return environ.Bootstrap(ctx, args)
}

func assertEnvironDestroyed(c *gc.C, env environs.Environ, store configstore.Storage) {
	_, err := store.ReadInfo(env.Config().Name())
	c.Assert(err, jc.Satisfies, errors.IsNotFound)

	_, err = env.Instances([]instance.Id{"invalid"})
	c.Assert(err, gc.ErrorMatches, "environment has been destroyed")
}

// setBootstrapEndpointAddress writes the API endpoint address of the
// bootstrap server into the connection information. This should only be run
// once directly after Bootstrap. It assumes that there is just one instance
// in the environment - the bootstrap instance.
func (c *bootstrapCommand) setBootstrapEndpointAddress(environ environs.Environ) error {
	instances, err := allInstances(environ)
	if err != nil {
		return errors.Trace(err)
	}
	length := len(instances)
	if length == 0 {
		return errors.Errorf("found no instances, expected at least one")
	}
	if length > 1 {
		logger.Warningf("expected one instance, got %d", length)
	}
	bootstrapInstance := instances[0]

	// Don't use c.ConnectionEndpoint as it attempts to contact the state
	// server if no addresses are found in connection info.
	netAddrs, err := bootstrapInstance.Addresses()
	if err != nil {
		return errors.Annotate(err, "failed to get bootstrap instance addresses")
	}
	cfg := environ.Config()
	apiPort := cfg.APIPort()
	apiHostPorts := network.AddressesWithPort(netAddrs, apiPort)
	return juju.UpdateControllerAddresses(c.ClientStore(), c.controllerName, nil, apiHostPorts...)
}

func SetImageMetadata(env environs.Environ, series, arches []string, out *[]*imagemetadata.ImageMetadata) error {
	hasRegion, ok := env.(simplestreams.HasRegion)
	if !ok {
		return nil
	}
	sources, err := environs.ImageMetadataSources(env)
	if err != nil {
		return errors.Trace(err)
	}
	region, err := hasRegion.Region()
	if err != nil {
		return errors.Trace(err)
	}
	imageConstraint := imagemetadata.NewImageConstraint(simplestreams.LookupParams{
		CloudSpec: region,
		Series:    series,
		Arches:    arches,
		Stream:    env.Config().ImageStream(),
	})
	imageMetadata, _, err := imagemetadata.Fetch(sources, imageConstraint)
	if err != nil {
		return errors.Trace(err)
	}
	*out = imageMetadata
	return nil
}

func (s *localJujuTestSuite) makeFakeInitScripts(c *gc.C, env environs.Environ) (installable, installable) {
	s.MakeTool(c, "start", `echo "some-service start/running, process 123"`)
	namespace := env.Config().AllAttrs()["namespace"].(string)

	// Mongo first...
	mongoName := mongo.ServiceName(namespace)
	mongoConf := common.Conf{
		Desc:      "fake mongo",
		ExecStart: "echo FAKE",
	}
	mongoService := local.NewService(mongoName, mongoConf, s.svcData)
	s.svcData.SetStatus(mongoName, "installed")
	installed, err := mongoService.Installed()
	c.Assert(err, jc.ErrorIsNil)
	c.Check(installed, jc.IsTrue)

	// ...then the machine agent
	agentName := fmt.Sprintf("juju-agent-%s", namespace)
	agentConf := common.Conf{
		Desc:      "fake agent",
		ExecStart: "echo FAKE",
	}
	agentService := local.NewService(agentName, agentConf, s.svcData)
	s.svcData.SetStatus(agentName, "installed")
	installed, err = agentService.Installed()
	c.Assert(err, jc.ErrorIsNil)
	c.Check(installed, jc.IsTrue)

	return mongoService, agentService
}

// GetMetadataSources returns the sources to use when looking for
// simplestreams tools metadata for the given stream.
func GetMetadataSources(env environs.Environ) ([]simplestreams.DataSource, error) {
	config := env.Config()

	// Add configured and environment-specific datasources.
	var sources []simplestreams.DataSource
	if userURL, ok := config.AgentMetadataURL(); ok {
		verify := utils.VerifySSLHostnames
		if !config.SSLHostnameVerification() {
			verify = utils.NoVerifySSLHostnames
		}
		sources = append(sources, simplestreams.NewURLSignedDataSource(conf.AgentMetadataURLKey, userURL, juju.JujuPublicKey, verify, simplestreams.SPECIFIC_CLOUD_DATA, false))
	}

	envDataSources, err := environmentDataSources(env)
	if err != nil {
		return nil, err
	}
	sources = append(sources, envDataSources...)

	// Add the default, public datasource.
	defaultURL, err := ToolsURL(DefaultBaseURL)
	if err != nil {
		return nil, err
	}
	if defaultURL != "" {
		sources = append(sources,
			simplestreams.NewURLSignedDataSource("default simplestreams", defaultURL, juju.JujuPublicKey, utils.VerifySSLHostnames, simplestreams.DEFAULT_CLOUD_DATA, true))
	}
	return sources, nil
}

func (s *localJujuTestSuite) makeFakeUpstartScripts(c *gc.C, env environs.Environ,
) (mongoService *upstart.Service, machineAgent *upstart.Service) {
	upstartDir := c.MkDir()
	s.PatchValue(&upstart.InitDir, upstartDir)
	s.MakeTool(c, "start", `echo "some-service start/running, process 123"`)

	namespace := env.Config().AllAttrs()["namespace"].(string)
	mongoConf := common.Conf{
		Desc: "fake mongo",
		Cmd:  "echo FAKE",
	}
	mongoService = upstart.NewService(mongo.ServiceName(namespace), mongoConf)
	err := mongoService.Install()
	c.Assert(err, gc.IsNil)
	c.Assert(mongoService.Installed(), jc.IsTrue)

	agentConf := common.Conf{
		Desc: "fake agent",
		Cmd:  "echo FAKE",
	}
	machineAgent = upstart.NewService(fmt.Sprintf("juju-agent-%s", namespace), agentConf)

	err = machineAgent.Install()
	c.Assert(err, gc.IsNil)
	c.Assert(machineAgent.Installed(), jc.IsTrue)

	return mongoService, machineAgent
}

// newState returns a new State that uses the given environment.
// The environment must have already been bootstrapped.
func newState(environ environs.Environ, mongoInfo *mongo.MongoInfo) (*state.State, error) {
	config := environ.Config()
	password := config.AdminSecret()
	if password == "" {
		return nil, fmt.Errorf("cannot connect without admin-secret")
	}
	modelTag := names.NewModelTag(config.UUID())

	mongoInfo.Password = password
	opts := mongo.DefaultDialOpts()
	st, err := state.Open(modelTag, mongoInfo, opts, environs.NewStatePolicy())
	if errors.IsUnauthorized(errors.Cause(err)) {
		// We try for a while because we might succeed in
		// connecting to mongo before the state has been
		// initialized and the initial password set.
		for a := redialStrategy.Start(); a.Next(); {
			st, err = state.Open(modelTag, mongoInfo, opts, environs.NewStatePolicy())
			if !errors.IsUnauthorized(errors.Cause(err)) {
				break
			}
		}
		if err != nil {
			return nil, err
		}
	} else if err != nil {
		return nil, err
	}
	if err := updateSecrets(environ, st); err != nil {
		st.Close()
		return nil, fmt.Errorf("unable to push secrets: %v", err)
	}
	return st, nil
}

// validateUploadAllowed returns an error if an attempt to upload tools should
// not be allowed.
func validateUploadAllowed(env environs.Environ, toolsArch *string) error {
	// Now check that the architecture for which we are setting up an
	// environment matches that from which we are bootstrapping.
	hostArch := arch.HostArch()
	// We can't build tools for a different architecture if one is specified.
	if toolsArch != nil && *toolsArch != hostArch {
		return fmt.Errorf("cannot build tools for %q using a machine running on %q", *toolsArch, hostArch)
	}
	// If no architecture is specified, ensure the target provider supports instances matching our architecture.
	supportedArchitectures, err := env.SupportedArchitectures()
	if err != nil {
		return fmt.Errorf(
			"no packaged tools available and cannot determine environment's supported architectures: %v", err)
	}
	archSupported := false
	for _, arch := range supportedArchitectures {
		if hostArch == arch {
			archSupported = true
			break
		}
	}
	if !archSupported {
		envType := env.Config().Type()
		return errors.Errorf("environment %q of type %s does not support instances running on %q", env.Config().Name(), envType, hostArch)
	}
	return nil
}

func assertEnvironNotDestroyed(c *gc.C, env environs.Environ, store configstore.Storage) {
	info, err := store.ReadInfo(env.Config().Name())
	c.Assert(err, gc.IsNil)
	c.Assert(info.Initialized(), jc.IsTrue)

	_, err = environs.NewFromName(env.Config().Name(), store)
	c.Assert(err, gc.IsNil)
}

func makeTestMetadata(c *gc.C, env environs.Environ, series, location string, im []*imagemetadata.ImageMetadata) {
	cloudSpec := simplestreams.CloudSpec{
		Region:   location,
		Endpoint: "https://management.core.windows.net/",
	}
	err := imagemetadata.MergeAndWriteMetadata(series, im, &cloudSpec, env.Storage())
	c.Assert(err, gc.IsNil)
}

// populateTools stores uploaded tools in provider storage
// and updates the tools metadata.
//
// TODO(axw) store tools in gridfs, catalogue in state.
func (c *BootstrapCommand) populateTools(env environs.Environ) error {
	agentConfig := c.CurrentConfig()
	dataDir := agentConfig.DataDir()
	tools, err := agenttools.ReadTools(dataDir, version.Current)
	if err != nil {
		return err
	}
	if !strings.HasPrefix(tools.URL, "file://") {
		// Nothing to do since the tools were not uploaded.
		return nil
	}

	// This is a hack: providers using localstorage (local, manual)
	// can't use storage during bootstrap as the localstorage worker
	// isn't running. Use filestorage instead.
	var stor storage.Storage
	storageDir := agentConfig.Value(agent.StorageDir)
	if storageDir != "" {
		stor, err = filestorage.NewFileStorageWriter(storageDir)
		if err != nil {
			return err
		}
	} else {
		stor = env.Storage()
	}

	// Create a temporary directory to contain source and cloned tools.
	tempDir, err := ioutil.TempDir("", "juju-sync-tools")
	if err != nil {
		return err
	}
	defer os.RemoveAll(tempDir)
	destTools := filepath.Join(tempDir, filepath.FromSlash(envtools.StorageName(tools.Version)))
	if err := os.MkdirAll(filepath.Dir(destTools), 0700); err != nil {
		return err
	}
	srcTools := filepath.Join(
		agenttools.SharedToolsDir(dataDir, version.Current),
		"tools.tar.gz",
	)
	if err := utils.CopyFile(destTools, srcTools); err != nil {
		return err
	}

	// Until we catalogue tools in state, we clone the tools
	// for each of the supported series of the same OS.
	otherSeries := version.OSSupportedSeries(version.Current.OS)
	_, err = sync.SyncBuiltTools(stor, &sync.BuiltTools{
		Version:     tools.Version,
		Dir:         tempDir,
		StorageName: envtools.StorageName(tools.Version),
		Sha256Hash:  tools.SHA256,
		Size:        tools.Size,
	}, otherSeries...)
	return err
}

// Destroy is a common implementation of the Destroy method defined on
// environs.Environ; we strongly recommend that this implementation be
// used when writing a new provider.
func Destroy(env environs.Environ) error {
	logger.Infof("destroying model %q", env.Config().Name())
	if err := destroyInstances(env); err != nil {
		return errors.Annotate(err, "destroying instances")
	}
	if err := destroyStorage(env); err != nil {
		return errors.Annotate(err, "destroying storage")
	}
	return nil
}

// StartInstanceWithParams is a test helper function that starts an instance
// with the given parameters, and a plausible but invalid configuration, and
// returns the result of Environ.StartInstance. The provided params's
// InstanceConfig and Tools field values will be ignored.
func StartInstanceWithParams(
	env environs.Environ, machineId string,
	params environs.StartInstanceParams,
) (
	*environs.StartInstanceResult, error,
) {
	if err := fillinStartInstanceParams(env, machineId, false, &params); err != nil {
		return nil, err
	}
	return env.StartInstance(params)
}

func findInstanceTools(env environs.Environ, series, arch string) (*tools.Tools, error) {
	agentVersion, ok := env.Config().AgentVersion()
	if !ok {
		return nil, fmt.Errorf("no agent version set in environment configuration")
	}
	possibleTools, err := envtools.FindInstanceTools(env, agentVersion, series, &arch)
	if err != nil {
		return nil, err
	}
	return possibleTools[0], nil
}

func validateConstraints(env environs.Environ, cons constraints.Value) error {
	validator, err := env.ConstraintsValidator()
	if err != nil {
		return err
	}
	unsupported, err := validator.Validate(cons)
	if len(unsupported) > 0 {
		logger.Warningf("unsupported constraints: %v", unsupported)
	}
	return err
}

func publicAttrs(e environs.Environ) map[string]interface{} {
	cfg := e.Config()
	secrets, err := e.Provider().SecretAttrs(cfg)
	if err != nil {
		panic(err)
	}
	attrs := cfg.AllAttrs()
	for attr := range secrets {
		delete(attrs, attr)
	}
	return attrs
}

// findAvailableTools returns a list of available tools,
// including tools that may be locally built and then
// uploaded. Tools that need to be built will have an
// empty URL.
func findAvailableTools(env environs.Environ, arch *string, upload bool) (coretools.List, error) {
	if upload {
		// We're forcing an upload: ensure we can do so.
		if err := validateUploadAllowed(env, arch); err != nil {
			return nil, err
		}
		return locallyBuildableTools(), nil
	}

	// We're not forcing an upload, so look for tools
	// in the environment's simplestreams search paths
	// for existing tools.
	var vers *version.Number
	if agentVersion, ok := env.Config().AgentVersion(); ok {
		vers = &agentVersion
	}
	dev := version.Current.IsDev() || env.Config().Development()
	logger.Debugf("looking for bootstrap tools: version=%v", vers)
	toolsList, findToolsErr := findBootstrapTools(env, vers, arch, dev)
	if findToolsErr != nil && !errors.IsNotFound(findToolsErr) {
		return nil, findToolsErr
	}

	if !dev || vers != nil {
		// We are not running a development build, or agent-version
		// was specified; the only tools available are the ones we've
		// just found.
		return toolsList, findToolsErr
	}
	// The tools located may not include the ones that the
	// provider requires. We are running a development build,
	// so augment the list of tools with those that we can build
	// locally.

	// Collate the set of arch+series that are externally available
	// so we can see if we need to build any locally. If we need
	// to, only then do we validate that we can upload (which
	// involves a potentially expensive SupportedArchitectures call).
	var archSeries set.Strings
	for _, tools := range toolsList {
		archSeries.Add(tools.Version.Arch + tools.Version.Series)
	}
	var localToolsList coretools.List
	for _, tools := range locallyBuildableTools() {
		if !archSeries.Contains(tools.Version.Arch + tools.Version.Series) {
			localToolsList = append(localToolsList, tools)
		}
	}
	if len(localToolsList) == 0 || validateUploadAllowed(env, arch) != nil {
		return toolsList, findToolsErr
	}
	return append(toolsList, localToolsList...), nil
}