package templates

import (
	"context"
	"fmt"
	"path/filepath"
	"strings"

	"github.com/aws/eks-anywhere/pkg/api/v1alpha1"
	"github.com/aws/eks-anywhere/pkg/executables"
	"github.com/aws/eks-anywhere/pkg/logger"
	"github.com/aws/eks-anywhere/pkg/providers/vsphere/internal/tags"
)

const (
	libraryContentCorrupted    = "1"
	libraryContentDoesNotExist = "-1"
)

type Factory struct {
	client          GovcClient
	datacenter      string
	datastore       string
	network         string
	resourcePool    string
	templateLibrary string
	tagsFactory     *tags.Factory
}

type GovcClient interface {
	CreateLibrary(ctx context.Context, datastore, library string) error
	DeployTemplateFromLibrary(ctx context.Context, templateDir, templateName, library, datacenter, datastore, network, resourcePool string, resizeBRDisk bool) error
	SearchTemplate(ctx context.Context, datacenter, template string) (string, error)
	ImportTemplate(ctx context.Context, library, ovaURL, name string) error
	LibraryElementExists(ctx context.Context, library string) (bool, error)
	GetLibraryElementContentVersion(ctx context.Context, element string) (string, error)
	DeleteLibraryElement(ctx context.Context, element string) error
	ListTags(ctx context.Context) ([]executables.Tag, error)
	CreateTag(ctx context.Context, tag, category string) error
	AddTag(ctx context.Context, path, tag string) error
	ListCategories(ctx context.Context) ([]string, error)
	CreateCategoryForVM(ctx context.Context, name string) error
	CreateUser(ctx context.Context, username string, password string) error
	UserExists(ctx context.Context, username string) (bool, error)
	CreateGroup(ctx context.Context, name string) error
	GroupExists(ctx context.Context, name string) (bool, error)
	AddUserToGroup(ctx context.Context, name string, username string) error
	RoleExists(ctx context.Context, name string) (bool, error)
	CreateRole(ctx context.Context, name string, privileges []string) error
	SetGroupRoleOnObject(ctx context.Context, principal string, role string, object string, domain string) error
}

func NewFactory(client GovcClient, datacenter, datastore, network, resourcePool, templateLibrary string) *Factory {
	return &Factory{
		client:          client,
		datacenter:      datacenter,
		datastore:       datastore,
		network:         network,
		resourcePool:    resourcePool,
		templateLibrary: templateLibrary,
		tagsFactory:     tags.NewFactory(client),
	}
}

func (f *Factory) CreateIfMissing(ctx context.Context, datacenter string, machineConfig *v1alpha1.VSphereMachineConfig, ovaURL string, tagsByCategory map[string][]string) error {
	templateFullPath, err := f.client.SearchTemplate(ctx, datacenter, machineConfig.Spec.Template)
	if err != nil {
		return fmt.Errorf("checking for template: %v", err)
	}
	if err == nil && len(templateFullPath) > 0 {
		machineConfig.Spec.Template = templateFullPath // TODO: move this out of the factory into the defaulter, it's a side effect
		logger.V(2).Info("Template already exists. Skipping creation", "template", machineConfig.Spec.Template)
		return nil
	}

	logger.V(2).Info("Template not available. Creating", "template", machineConfig.Spec.Template)

	osFamily := machineConfig.Spec.OSFamily
	if err = f.createTemplate(ctx, machineConfig.Spec.Template, ovaURL, string(osFamily)); err != nil {
		return err
	}

	if err = f.tagsFactory.TagTemplate(ctx, machineConfig.Spec.Template, tagsByCategory); err != nil {
		return err
	}
	return nil
}

func (f *Factory) createTemplate(ctx context.Context, templatePath, ovaURL, osFamily string) error {
	if err := f.createLibraryIfMissing(ctx); err != nil {
		return err
	}

	logger.Info("Creating template. This might take a while.") // TODO: add rough estimate timing?
	templateName := filepath.Base(templatePath)
	templateDir := filepath.Dir(templatePath)

	if err := f.importOVAIfMissing(ctx, templateName, ovaURL); err != nil {
		return err
	}

	var resizeBRDisk bool
	if strings.EqualFold(osFamily, string(v1alpha1.Bottlerocket)) {
		resizeBRDisk = true
	}
	if err := f.client.DeployTemplateFromLibrary(ctx, templateDir, templateName, f.templateLibrary, f.datacenter, f.datastore, f.network, f.resourcePool, resizeBRDisk); err != nil {
		return fmt.Errorf("failed deploying template: %v", err)
	}

	return nil
}

func (f *Factory) createLibraryIfMissing(ctx context.Context) error {
	libraryExists, err := f.client.LibraryElementExists(ctx, f.templateLibrary)
	if err != nil {
		return fmt.Errorf("failed to validate library for new template: %v", err)
	}

	if !libraryExists {
		logger.V(2).Info("Creating library", "library", f.templateLibrary)
		if err = f.client.CreateLibrary(ctx, f.datastore, f.templateLibrary); err != nil {
			return fmt.Errorf("failed creating library for new template: %v", err)
		}
	}

	return nil
}

func (f *Factory) importOVAIfMissing(ctx context.Context, templateName, ovaURL string) error {
	contentVersion, err := f.client.GetLibraryElementContentVersion(ctx, filepath.Join(f.templateLibrary, templateName))
	if err != nil {
		return fmt.Errorf("failed to validate template in library for new template: %v", err)
	}

	if contentVersion == libraryContentCorrupted {
		err := f.client.DeleteLibraryElement(ctx, filepath.Join(f.templateLibrary, templateName))
		if err != nil {
			return fmt.Errorf("failed to delete old template in library: %v", err)
		}
		contentVersion = libraryContentDoesNotExist
	}

	if contentVersion == libraryContentDoesNotExist {
		logger.V(2).Info("Importing template from ova url", "ova", ovaURL)
		if err = f.client.ImportTemplate(ctx, f.templateLibrary, ovaURL, templateName); err != nil {
			return fmt.Errorf("failed importing template into library: %v", err)
		}
	}

	return nil
}