package arm

import (
	"context"
	"errors"
	"fmt"
	"net/url"
	"strings"
	"time"

	"github.com/hashicorp/packer/builder/azure/common/constants"
	"github.com/hashicorp/packer/common/retry"
	"github.com/hashicorp/packer/helper/multistep"
	"github.com/hashicorp/packer/packer"
)

type StepDeployTemplate struct {
	client     *AzureClient
	deploy     func(ctx context.Context, resourceGroupName string, deploymentName string) error
	delete     func(ctx context.Context, deploymentName, resourceGroupName string) error
	disk       func(ctx context.Context, resourceGroupName string, computeName string) (string, string, error)
	deleteDisk func(ctx context.Context, imageType string, imageName string, resourceGroupName string) error
	say        func(message string)
	error      func(e error)
	config     *Config
	factory    templateFactoryFunc
	name       string
}

func NewStepDeployTemplate(client *AzureClient, ui packer.Ui, config *Config, deploymentName string, factory templateFactoryFunc) *StepDeployTemplate {
	var step = &StepDeployTemplate{
		client:  client,
		say:     func(message string) { ui.Say(message) },
		error:   func(e error) { ui.Error(e.Error()) },
		config:  config,
		factory: factory,
		name:    deploymentName,
	}

	step.deploy = step.deployTemplate
	step.delete = step.deleteDeploymentResources
	step.disk = step.getImageDetails
	step.deleteDisk = step.deleteImage
	return step
}

func (s *StepDeployTemplate) Run(ctx context.Context, state multistep.StateBag) multistep.StepAction {
	s.say("Deploying deployment template ...")

	var resourceGroupName = state.Get(constants.ArmResourceGroupName).(string)
	s.say(fmt.Sprintf(" -> ResourceGroupName : '%s'", resourceGroupName))
	s.say(fmt.Sprintf(" -> DeploymentName    : '%s'", s.name))

	return processStepResult(
		s.deploy(ctx, resourceGroupName, s.name),
		s.error, state)
}

func (s *StepDeployTemplate) Cleanup(state multistep.StateBag) {
	defer func() {
		err := s.deleteTemplate(context.Background(), state)
		if err != nil {
			s.say(s.client.LastError.Error())
		}
	}()

	// Only clean up if this is an existing resource group that has been verified to exist.
	// ArmIsResourceGroupCreated is set in step_create_resource_group to true, when Packer has verified that the resource group exists.
	// ArmIsExistingResourceGroup is set to true when build_resource_group is set in the Packer configuration.
	existingResourceGroup := state.Get(constants.ArmIsExistingResourceGroup).(bool)
	resourceGroupCreated := state.Get(constants.ArmIsResourceGroupCreated).(bool)
	if !existingResourceGroup || !resourceGroupCreated {
		return
	}

	ui := state.Get("ui").(packer.Ui)
	ui.Say("\nThe resource group was not created by Packer, deleting individual resources ...")

	deploymentName := s.name
	resourceGroupName := state.Get(constants.ArmResourceGroupName).(string)
	err := s.deleteDeploymentResources(context.TODO(), deploymentName, resourceGroupName)
	if err != nil {
		s.reportIfError(err, resourceGroupName)
	}

	NewStepDeleteAdditionalDisks(s.client, ui).Run(context.TODO(), state)
}

func (s *StepDeployTemplate) deployTemplate(ctx context.Context, resourceGroupName string, deploymentName string) error {
	deployment, err := s.factory(s.config)
	if err != nil {
		return err
	}

	f, err := s.client.DeploymentsClient.CreateOrUpdate(ctx, resourceGroupName, deploymentName, *deployment)
	if err != nil {
		s.say(s.client.LastError.Error())
		return err
	}

	err = f.WaitForCompletionRef(ctx, s.client.DeploymentsClient.Client)
	if err == nil {
		s.say(s.client.LastError.Error())
	}

	return err
}

func (s *StepDeployTemplate) deleteTemplate(ctx context.Context, state multistep.StateBag) error {
	deploymentName := s.name
	resourceGroupName := state.Get(constants.ArmResourceGroupName).(string)
	ui := state.Get("ui").(packer.Ui)

	ui.Say(fmt.Sprintf("Removing the created Deployment object: '%s'", deploymentName))
	f, err := s.client.DeploymentsClient.Delete(ctx, resourceGroupName, deploymentName)
	if err != nil {
		return err
	}

	return f.WaitForCompletionRef(ctx, s.client.DeploymentsClient.Client)
}

func (s *StepDeployTemplate) getImageDetails(ctx context.Context, resourceGroupName string, computeName string) (string, string, error) {
	//We can't depend on constants.ArmOSDiskVhd being set
	var imageName, imageType string
	vm, err := s.client.VirtualMachinesClient.Get(ctx, resourceGroupName, computeName, "")
	if err != nil {
		return imageName, imageType, err
	}

	if vm.StorageProfile.OsDisk.Vhd != nil {
		imageType = "image"
		imageName = *vm.StorageProfile.OsDisk.Vhd.URI
		return imageType, imageName, nil
	}

	imageType = "Microsoft.Compute/disks"
	imageName = *vm.StorageProfile.OsDisk.ManagedDisk.ID

	return imageType, imageName, nil
}

//TODO(paulmey): move to helpers file
func deleteResource(ctx context.Context, client *AzureClient, resourceType string, resourceName string, resourceGroupName string) error {
	switch resourceType {
	case "Microsoft.Compute/virtualMachines":
		f, err := client.VirtualMachinesClient.Delete(ctx, resourceGroupName, resourceName)
		if err == nil {
			err = f.WaitForCompletionRef(ctx, client.VirtualMachinesClient.Client)
		}
		return err
	case "Microsoft.KeyVault/vaults":
		_, err := client.VaultClientDelete.Delete(ctx, resourceGroupName, resourceName)
		return err
	case "Microsoft.Network/networkInterfaces":
		f, err := client.InterfacesClient.Delete(ctx, resourceGroupName, resourceName)
		if err == nil {
			err = f.WaitForCompletionRef(ctx, client.InterfacesClient.Client)
		}
		return err
	case "Microsoft.Network/virtualNetworks":
		f, err := client.VirtualNetworksClient.Delete(ctx, resourceGroupName, resourceName)
		if err == nil {
			err = f.WaitForCompletionRef(ctx, client.VirtualNetworksClient.Client)
		}
		return err
	case "Microsoft.Network/networkSecurityGroups":
		f, err := client.SecurityGroupsClient.Delete(ctx, resourceGroupName, resourceName)
		if err == nil {
			err = f.WaitForCompletionRef(ctx, client.SecurityGroupsClient.Client)
		}
		return err
	case "Microsoft.Network/publicIPAddresses":
		f, err := client.PublicIPAddressesClient.Delete(ctx, resourceGroupName, resourceName)
		if err == nil {
			err = f.WaitForCompletionRef(ctx, client.PublicIPAddressesClient.Client)
		}
		return err
	}
	return nil
}

func (s *StepDeployTemplate) deleteImage(ctx context.Context, imageType string, imageName string, resourceGroupName string) error {
	// Managed disk
	if imageType == "Microsoft.Compute/disks" {
		xs := strings.Split(imageName, "/")
		diskName := xs[len(xs)-1]
		f, err := s.client.DisksClient.Delete(ctx, resourceGroupName, diskName)
		if err == nil {
			err = f.WaitForCompletionRef(ctx, s.client.DisksClient.Client)
		}
		return err
	}

	// VHD image
	u, err := url.Parse(imageName)
	if err != nil {
		return err
	}
	xs := strings.Split(u.Path, "/")
	if len(xs) < 3 {
		return errors.New("Unable to parse path of image " + imageName)
	}
	var storageAccountName = xs[1]
	var blobName = strings.Join(xs[2:], "/")

	blob := s.client.BlobStorageClient.GetContainerReference(storageAccountName).GetBlobReference(blobName)
	_, err = blob.BreakLease(nil)
	if err != nil && !strings.Contains(err.Error(), "LeaseNotPresentWithLeaseOperation") {
		s.say(s.client.LastError.Error())
		return err
	}

	return blob.Delete(nil)
}

func (s *StepDeployTemplate) deleteDeploymentResources(ctx context.Context, deploymentName, resourceGroupName string) error {
	var maxResources int32 = 50
	deploymentOperations, err := s.client.DeploymentOperationsClient.ListComplete(ctx, resourceGroupName, deploymentName, &maxResources)
	if err != nil {
		s.reportIfError(err, resourceGroupName)
		return err
	}

	for deploymentOperations.NotDone() {
		deploymentOperation := deploymentOperations.Value()
		// Sometimes an empty operation is added to the list by Azure
		if deploymentOperation.Properties.TargetResource == nil {
			_ = deploymentOperations.Next()
			continue
		}

		resourceName := *deploymentOperation.Properties.TargetResource.ResourceName
		resourceType := *deploymentOperation.Properties.TargetResource.ResourceType

		s.say(fmt.Sprintf(" -> %s : '%s'", resourceType, resourceName))

		err = retry.Config{
			Tries:      10,
			RetryDelay: (&retry.Backoff{InitialBackoff: 10 * time.Second, MaxBackoff: 600 * time.Second, Multiplier: 2}).Linear,
		}.Run(ctx, func(ctx context.Context) error {
			err := deleteResource(ctx, s.client,
				resourceType,
				resourceName,
				resourceGroupName)
			if err != nil {
				s.reportIfError(err, resourceName)
			}
			return nil
		})
		if err != nil {
			s.reportIfError(err, resourceName)
		}

		if err = deploymentOperations.Next(); err != nil {
			return err
		}
	}

	return nil
}

func (s *StepDeployTemplate) reportIfError(err error, resourceName string) {
	if err != nil {
		s.say(fmt.Sprintf("Error deleting resource. Please delete manually.\n\n"+
			"Name: %s\n"+
			"Error: %s", resourceName, err.Error()))
		s.error(err)
	}
}