// Upload stemcell to an IAAS. It does the following steps:
// 1) uploads the stemcell to the cloud (if needed),
// 2) saves a record of the uploaded stemcell in the repo
func (m *manager) Upload(extractedStemcell ExtractedStemcell, uploadStage biui.Stage) (cloudStemcell CloudStemcell, err error) {
	manifest := extractedStemcell.Manifest()
	stageName := fmt.Sprintf("Uploading stemcell '%s/%s'", manifest.Name, manifest.Version)
	err = uploadStage.Perform(stageName, func() error {
		foundStemcellRecord, found, err := m.repo.Find(manifest.Name, manifest.Version)
		if err != nil {
			return bosherr.WrapError(err, "Finding existing stemcell record in repo")
		}

		if found {
			cloudStemcell = NewCloudStemcell(foundStemcellRecord, m.repo, m.cloud)
			return biui.NewSkipStageError(bosherr.Errorf("Found stemcell: %#v", foundStemcellRecord), "Stemcell already uploaded")
		}

		cid, err := m.cloud.CreateStemcell(manifest.ImagePath, manifest.CloudProperties)
		if err != nil {
			return bosherr.WrapErrorf(err, "creating stemcell (%s %s)", manifest.Name, manifest.Version)
		}

		stemcellRecord, err := m.repo.Save(manifest.Name, manifest.Version, cid)
		if err != nil {
			//TODO: delete stemcell from cloud when saving fails
			return bosherr.WrapErrorf(err, "saving stemcell record in repo (cid=%s, stemcell=%s)", cid, extractedStemcell)
		}

		cloudStemcell = NewCloudStemcell(stemcellRecord, m.repo, m.cloud)
		return nil
	})
	if err != nil {
		return cloudStemcell, err
	}

	return cloudStemcell, nil
}

func (i *instance) UpdateJobs(
	deploymentManifest bideplmanifest.Manifest,
	stage biui.Stage,
) error {
	newState, err := i.stateBuilder.Build(i.jobName, i.id, deploymentManifest, stage)
	if err != nil {
		return bosherr.WrapErrorf(err, "Building state for instance '%s/%d'", i.jobName, i.id)
	}

	stepName := fmt.Sprintf("Updating instance '%s/%d'", i.jobName, i.id)
	err = stage.Perform(stepName, func() error {
		err := i.vm.Stop()
		if err != nil {
			return bosherr.WrapError(err, "Stopping the agent")
		}

		err = i.vm.Apply(newState.ToApplySpec())
		if err != nil {
			return bosherr.WrapError(err, "Applying the agent state")
		}

		err = i.vm.Start()
		if err != nil {
			return bosherr.WrapError(err, "Starting the agent")
		}

		return nil
	})
	if err != nil {
		return err
	}

	return i.waitUntilJobsAreRunning(deploymentManifest.Update.UpdateWatchTime, stage)
}

func (i *instance) shutdown(
	pingTimeout time.Duration,
	pingDelay time.Duration,
	stage biui.Stage,
) error {
	stepName := fmt.Sprintf("Waiting for the agent on VM '%s'", i.vm.CID())
	waitingForAgentErr := stage.Perform(stepName, func() error {
		if err := i.vm.WaitUntilReady(pingTimeout, pingDelay); err != nil {
			return bosherr.WrapError(err, "Agent unreachable")
		}
		return nil
	})
	if waitingForAgentErr != nil {
		i.logger.Warn(i.logTag, "Gave up waiting for agent: %s", waitingForAgentErr.Error())
		return nil
	}

	if err := i.stopJobs(stage); err != nil {
		return err
	}
	if err := i.unmountDisks(stage); err != nil {
		return err
	}
	return nil
}

func (i *instance) Delete(
	pingTimeout time.Duration,
	pingDelay time.Duration,
	stage biui.Stage,
) error {
	vmExists, err := i.vm.Exists()
	if err != nil {
		return bosherr.WrapErrorf(err, "Checking existance of vm for instance '%s/%d'", i.jobName, i.id)
	}

	if vmExists {
		if err = i.shutdown(pingTimeout, pingDelay, stage); err != nil {
			return err
		}
	}

	// non-existent VMs still need to be 'deleted' to clean up related resources owned by the CPI
	stepName := fmt.Sprintf("Deleting VM '%s'", i.vm.CID())
	return stage.Perform(stepName, func() error {
		err := i.vm.Delete()
		cloudErr, ok := err.(bicloud.Error)
		if ok && cloudErr.Type() == bicloud.VMNotFoundError {
			return biui.NewSkipStageError(cloudErr, "VM not found")
		}
		return err
	})
}

func (s Fetcher) GetStemcell(deploymentManifest bideplmanifest.Manifest, stage biui.Stage) (ExtractedStemcell, error) {
	stemcell, err := deploymentManifest.Stemcell(deploymentManifest.JobName())
	if err != nil {
		return nil, err
	}

	stemcellTarballPath, err := s.TarballProvider.Get(stemcell, stage)
	if err != nil {
		return nil, err
	}

	var extractedStemcell ExtractedStemcell
	err = stage.Perform("Validating stemcell", func() error {
		extractedStemcell, err = s.StemcellExtractor.Extract(stemcellTarballPath)
		if err != nil {
			return bosherr.WrapErrorf(err, "Extracting stemcell from '%s'", stemcellTarballPath)
		}

		return nil
	})
	if err != nil {
		return nil, err
	}

	return extractedStemcell, nil
}

// renderJobTemplates renders all the release job templates for multiple release jobs specified
// by a deployment job and randomly uploads them to blobstore
func (b *jobRenderer) renderJobTemplates(
	releaseJobs []bireljob.Job,
	releaseJobProperties map[string]*biproperty.Map,
	jobProperties biproperty.Map,
	globalProperties biproperty.Map,
	deploymentName string,
	stage biui.Stage,
) ([]RenderedJobRef, error) {
	renderedJobRefs := make([]RenderedJobRef, 0, len(releaseJobs))
	err := stage.Perform("Rendering job templates", func() error {
		renderedJobList, err := b.jobListRenderer.Render(releaseJobs, releaseJobProperties, jobProperties, globalProperties, deploymentName, "")
		if err != nil {
			return err
		}
		defer renderedJobList.DeleteSilently()

		for _, renderedJob := range renderedJobList.All() {
			renderedJobRef, err := b.compressAndUpload(renderedJob)
			if err != nil {
				return err
			}

			renderedJobRefs = append(renderedJobRefs, renderedJobRef)
		}

		return nil
	})

	return renderedJobRefs, err
}

func (y DeploymentManifestParser) GetDeploymentManifest(deploymentManifestPath string, releaseSetManifest birelsetmanifest.Manifest, stage biui.Stage) (bideplmanifest.Manifest, error) {
	var deploymentManifest bideplmanifest.Manifest
	err := stage.Perform("Validating deployment manifest", func() error {
		var err error
		deploymentManifest, err = y.DeploymentParser.Parse(deploymentManifestPath)
		if err != nil {
			return bosherr.WrapErrorf(err, "Parsing deployment manifest '%s'", deploymentManifestPath)
		}

		err = y.DeploymentValidator.Validate(deploymentManifest, releaseSetManifest)
		if err != nil {
			return bosherr.WrapError(err, "Validating deployment manifest")
		}

		err = y.DeploymentValidator.ValidateReleaseJobs(deploymentManifest, y.ReleaseManager)
		if err != nil {
			return bosherr.WrapError(err, "Validating deployment jobs refer to jobs in release")
		}

		return nil
	})
	if err != nil {
		return bideplmanifest.Manifest{}, err
	}

	return deploymentManifest, nil
}

// compilePackages compiles the specified packages, in the order specified, uploads them to the Blobstore, and returns the blob references
func (c *dependencyCompiler) compilePackages(requiredPackages []*birelpkg.Package, stage biui.Stage) ([]CompiledPackageRef, error) {
	packageRefs := make([]CompiledPackageRef, 0, len(requiredPackages))

	for _, pkg := range requiredPackages {
		stepName := fmt.Sprintf("Compiling package '%s/%s'", pkg.Name, pkg.Fingerprint)
		err := stage.Perform(stepName, func() error {
			compiledPackageRecord, err := c.packageCompiler.Compile(pkg)
			if err != nil {
				return err
			}

			packageRef := CompiledPackageRef{
				Name:        pkg.Name,
				Version:     pkg.Fingerprint,
				BlobstoreID: compiledPackageRecord.BlobID,
				SHA1:        compiledPackageRecord.BlobSHA1,
			}
			packageRefs = append(packageRefs, packageRef)

			return nil
		})
		if err != nil {
			return nil, err
		}
	}

	return packageRefs, nil
}

func (i *installation) stopRegistryNice(logger boshlog.Logger, stage biui.Stage) {
	err := stage.Perform("Stopping registry", func() error {
		return i.StopRegistry()
	})
	if err != nil {
		logger.Warn("installation", "Registry failed to stop: %s", err)
	}
}

func (d *diskDeployer) attachDisk(disk bidisk.Disk, vm VM, stage biui.Stage) error {
	stageName := fmt.Sprintf("Attaching disk '%s' to VM '%s'", disk.CID(), vm.CID())
	err := stage.Perform(stageName, func() error {
		return vm.AttachDisk(disk)
	})

	return err
}

func (d *diskDeployer) createDisk(diskPool bideplmanifest.DiskPool, vm VM, stage biui.Stage) (disk bidisk.Disk, err error) {
	err = stage.Perform("Creating disk", func() error {
		disk, err = d.diskManager.Create(diskPool, vm.CID())
		return err
	})

	return disk, err
}

func (i *installation) WithRunningRegistry(logger boshlog.Logger, stage biui.Stage, fn func() error) error {
	err := stage.Perform("Starting registry", func() error {
		return i.StartRegistry()
	})
	if err != nil {
		return err
	}
	defer i.stopRegistryNice(logger, stage)
	return fn()
}

func (d *diskDeployer) migrateDisk(
	originalDisk bidisk.Disk,
	diskPool bideplmanifest.DiskPool,
	vm VM,
	stage biui.Stage,
) (newDisk bidisk.Disk, err error) {
	d.logger.Debug(d.logTag, "Migrating disk '%s'", originalDisk.CID())

	err = stage.Perform("Creating disk", func() error {
		newDisk, err = d.diskManager.Create(diskPool, vm.CID())
		return err
	})
	if err != nil {
		return newDisk, err
	}

	stageName := fmt.Sprintf("Attaching disk '%s' to VM '%s'", newDisk.CID(), vm.CID())
	err = stage.Perform(stageName, func() error {
		return vm.AttachDisk(newDisk)
	})
	if err != nil {
		return newDisk, err
	}

	stageName = fmt.Sprintf("Migrating disk content from '%s' to '%s'", originalDisk.CID(), newDisk.CID())
	err = stage.Perform(stageName, func() error {
		return vm.MigrateDisk()
	})
	if err != nil {
		return newDisk, err
	}

	err = d.updateCurrentDiskRecord(newDisk)
	if err != nil {
		return newDisk, err
	}

	stageName = fmt.Sprintf("Detaching disk '%s'", originalDisk.CID())
	err = stage.Perform(stageName, func() error {
		return vm.DetachDisk(originalDisk)
	})
	if err != nil {
		return newDisk, err
	}

	stageName = fmt.Sprintf("Deleting disk '%s'", originalDisk.CID())
	err = stage.Perform(stageName, func() error {
		return originalDisk.Delete()
	})
	if err != nil {
		return newDisk, err
	}

	return newDisk, nil
}

func (d *deployment) deleteDisk(deleteStage biui.Stage, disk bidisk.Disk) error {
	stepName := fmt.Sprintf("Deleting disk '%s'", disk.CID())
	return deleteStage.Perform(stepName, func() error {
		err := disk.Delete()
		cloudErr, ok := err.(bicloud.Error)
		if ok && cloudErr.Type() == bicloud.DiskNotFoundError {
			return biui.NewSkipStageError(cloudErr, "Disk not found")
		}
		return err
	})
}

func (d *deployment) deleteStemcell(deleteStage biui.Stage, stemcell bistemcell.CloudStemcell) error {
	stepName := fmt.Sprintf("Deleting stemcell '%s'", stemcell.CID())
	return deleteStage.Perform(stepName, func() error {
		err := stemcell.Delete()
		cloudErr, ok := err.(bicloud.Error)
		if ok && cloudErr.Type() == bicloud.StemcellNotFoundError {
			return biui.NewSkipStageError(cloudErr, "Stemcell not found")
		}
		return err
	})
}

func (i *instance) waitUntilJobsAreRunning(updateWatchTime bideplmanifest.WatchTime, stage biui.Stage) error {
	start := time.Duration(updateWatchTime.Start) * time.Millisecond
	end := time.Duration(updateWatchTime.End) * time.Millisecond
	delayBetweenAttempts := 1 * time.Second
	maxAttempts := int((end - start) / delayBetweenAttempts)

	stepName := fmt.Sprintf("Waiting for instance '%s/%d' to be running", i.jobName, i.id)
	return stage.Perform(stepName, func() error {
		time.Sleep(start)
		return i.vm.WaitToBeRunning(maxAttempts, delayBetweenAttempts)
	})
}

func (i CpiInstaller) installCpiRelease(installer biinstall.Installer, installationManifest biinstallmanifest.Manifest, target biinstall.Target, stage biui.Stage) (biinstall.Installation, error) {
	var installation biinstall.Installation
	var err error
	err = stage.PerformComplex("installing CPI", func(installStage biui.Stage) error {
		installation, err = installer.Install(installationManifest, installStage)
		return err
	})
	if err != nil {
		return installation, bosherr.WrapError(err, "Installing CPI")
	}

	return installation, nil
}

func (i CpiInstaller) ValidateCpiRelease(installationManifest biinstallmanifest.Manifest, stage biui.Stage) error {
	return stage.Perform("Validating cpi release", func() error {
		cpiReleaseName := installationManifest.Template.Release
		cpiRelease, found := i.ReleaseManager.Find(cpiReleaseName)
		if !found {
			return bosherr.Errorf("installation release '%s' must refer to a provided release", cpiReleaseName)
		}

		err := i.Validator.Validate(cpiRelease, installationManifest.Template.Name)
		if err != nil {
			return bosherr.WrapErrorf(err, "Invalid CPI release '%s'", cpiReleaseName)
		}
		return nil
	})
}

func (c *deploymentDeleter) findCurrentDeploymentAndDelete(stage biui.Stage, deploymentManager bidepl.Manager) error {
	c.logger.Debug(c.logTag, "Finding current deployment...")
	deployment, found, err := deploymentManager.FindCurrent()
	if err != nil {
		return bosherr.WrapError(err, "Finding current deployment")
	}

	return stage.PerformComplex("deleting deployment", func(deleteStage biui.Stage) error {
		if !found {
			//TODO: skip? would require adding skip support to PerformComplex
			c.logger.Debug(c.logTag, "No current deployment found...")
			return nil
		}

		return deployment.Delete(deleteStage)
	})
}

func (p *provider) Get(source Source, stage biui.Stage) (string, error) {
	if strings.HasPrefix(source.GetURL(), "file://") {
		filePath := strings.TrimPrefix(source.GetURL(), "file://")

		expandedPath, err := p.fs.ExpandPath(filePath)
		if err != nil {
			p.logger.Warn(p.logTag, "Failed to expand file path %s, using original URL", filePath)
			return filePath, nil
		}

		p.logger.Debug(p.logTag, "Using the tarball from file source: '%s'", filePath)
		return expandedPath, nil
	}

	if !strings.HasPrefix(source.GetURL(), "http") {
		return "", bosherr.Errorf("Invalid source URL: '%s', must be either file:// or http(s)://", source.GetURL())
	}

	var cachedPath string
	err := stage.Perform(fmt.Sprintf("Downloading %s", source.Description()), func() error {
		var found bool
		cachedPath, found = p.cache.Get(source)
		if found {
			p.logger.Debug(p.logTag, "Using the tarball from cache: '%s'", cachedPath)
			return biui.NewSkipStageError(bosherr.Error("Already downloaded"), "Found in local cache")
		}

		retryStrategy := boshretry.NewAttemptRetryStrategy(p.downloadAttempts, p.delayTimeout, p.downloadRetryable(source), p.logger)
		err := retryStrategy.Try()
		if err != nil {
			return bosherr.WrapErrorf(err, "Failed to download from '%s'", source.GetURL())
		}

		p.logger.Debug(p.logTag, "Using the downloaded tarball: '%s'", cachedPath)
		return nil
	})

	if err != nil {
		return "", err
	}

	return p.cache.Path(source), nil
}