package stacks

import (
	"context"
	_ "embed"
	"fmt"
	"os"
	"path/filepath"

	"github.com/pulumi/pulumi/sdk/v3/go/auto"
	"github.com/pulumi/pulumi/sdk/v3/go/auto/optdestroy"
	"github.com/pulumi/pulumi/sdk/v3/go/auto/optpreview"
	"github.com/pulumi/pulumi/sdk/v3/go/auto/optup"
	"github.com/pulumi/pulumi/sdk/v3/go/pulumi"
	"gitlab.com/dananglin/helix/internal/config"
	"gitlab.com/dananglin/helix/internal/docker"
)

// DockerStack is a stack for managing the containers
// for the forge platform.
type DockerStack struct {
	Name  string
	Stack auto.Stack
}

//go:embed templates/traefik/Dockerfile.tmpl
var templateTraefikDockerfile string

//go:embed templates/traefik/traefik.yaml.tmpl
var templateTraefikStaticConfig string

//go:embed templates/traefik/dynamic_dashboard.yaml.tmpl
var templateTraefikDynamicDashboardConfig string

//go:embed templates/traefik/entrypoint.sh.tmpl
var templateTraefikEntrypoint string

// newContainerStack creates the ContainerStack value.
func newDockerStack(ctx context.Context, project, stack string, c config.Config) (*DockerStack, error) {
	deployFunc := deployDockerStack(project, c.Docker, c.Services)

	s, err := createOrSelectStack(ctx, project, stack, deployFunc)
	if err != nil {
		return nil, fmt.Errorf("unable to initialise the '%s' stack...\n%w", stack, err)
	}

	d := DockerStack{
		Name:  stack,
		Stack: s,
	}

	return &d, nil
}

// Preview the proposed changes to the container stack.
func (c *DockerStack) Preview(ctx context.Context) error {
	streamer := optpreview.ProgressStreams(os.Stdout)
	_, err := c.Stack.Preview(ctx, streamer)
	if err != nil {
		return fmt.Errorf("unable to preview the '%s' stack...\n%w", c.Name, err)
	}
	return nil
}

// Update the container stack.
func (c *DockerStack) Update(ctx context.Context) error {
	streamer := optup.ProgressStreams(os.Stdout)
	_, err := c.Stack.Up(ctx, streamer)
	if err != nil {
		return fmt.Errorf("unable to update '%s' stack...\n%w", c.Name, err)
	}
	return nil
}

// Destroy the container stack.
func (c *DockerStack) Destroy(ctx context.Context) error {
	streamer := optdestroy.ProgressStreams(os.Stdout)
	_, err := c.Stack.Destroy(ctx, streamer)
	if err != nil {
		return fmt.Errorf("unable to destroy '%s' stack...\n%w", c.Name, err)
	}
	return nil
}

// deployDockerStack returns a Pulumi run function
// that is used to deploy the docker stack.
func deployDockerStack(project string, dockerConfig config.DockerConfig, services config.ServicesConfig) pulumi.RunFunc {
	groupID := 2239
	services.Traefik.GroupId = groupID

	return func(ctx *pulumi.Context) error {
		// TODO: Create the provider when we start playing with remote hosts

		// Create the docker network
		networkConfig := docker.DockerNetworkConfig{
			Name:   pulumi.String(dockerConfig.Network.Name),
			Subnet: pulumi.String(dockerConfig.Network.Subnet),
			Driver: pulumi.String(dockerConfig.Network.Driver),
		}

		network, err := docker.CreateNetwork(ctx, networkConfig)
		if err != nil {
			return err
		}

		// Create the shared volume
		sharedVolumeInput := docker.DockerVolumeInput{
			Name:        pulumi.String(dockerConfig.SharedVolume.Name),
			UniqueLabel: "shared",
		}

		sharedVolume, err := docker.CreateVolume(ctx, sharedVolumeInput)
		if err != nil {
			return err
		}

		base_cache, err := os.UserCacheDir()
		if err != nil {
			return fmt.Errorf("unable to get the base cache directory...\n%w", err)
		}

		// Create the Traefik service
		traefikContextDir := filepath.Join(base_cache, "helix", project, "traefik")

		if err := os.MkdirAll(traefikContextDir, 0700); err != nil {
			return fmt.Errorf("unable to make the cache directory for traefik...\n%w", err)
		}

		if err := generateFile(services.Traefik, templateTraefikDockerfile, "traefikDocker", filepath.Join(traefikContextDir, "Dockerfile")); err != nil {
			return fmt.Errorf("unable to generate the Traefik Dockerfile from template...\n%w", err)
		}

		if err := generateFile(services.Traefik, templateTraefikStaticConfig, "traefikStaticConf", filepath.Join(traefikContextDir, "traefik.yml")); err != nil {
			return fmt.Errorf("unable to generate the Traefik static configuration from template...\n%w", err)
		}

		if err := generateFile(services.Traefik, templateTraefikDynamicDashboardConfig, "traefikDashboardConf", filepath.Join(traefikContextDir, "dynamic_dashboard.yaml")); err != nil {
			return fmt.Errorf("unable to generate the Traefik dashboard configuration from template...\n%w", err)
		}

		if err := generateFile(services.Traefik, templateTraefikEntrypoint, "traefikEntrypoint", filepath.Join(traefikContextDir, "entrypoint.sh")); err != nil {
			return fmt.Errorf("unable to generate the Traefik entrypoint script from template...\n%w", err)
		}

		c := docker.DockerImageInput{
			BuildContext: pulumi.String(traefikContextDir),
			Dockerfile:   pulumi.String(filepath.Join(traefikContextDir, "Dockerfile")),
			ImageName:    pulumi.String("helix-traefik"),
			ImageTag:     pulumi.String(services.Traefik.Version),
			UniqueLabel:  "traefik-image",
		}

		traefikImage, err := docker.CreateImage(ctx, c)
		if err != nil {
			return err
		}

		traefikContainerInput := docker.DockerContainerInput{
			Image:       traefikImage.ImageName,
			Ipv4Address: pulumi.String(services.Traefik.ContainerIp),
			Name:        pulumi.String("helix-traefik"),
			Network:     network.Name,
			UniqueLabel: "traefik-container",
			DockerVolumes: []docker.DockerVolume{
				{
					Name:      sharedVolume.Name,
					MountPath: pulumi.String("/helix/shared"),
				},
			},
		}

		if err = docker.CreateContainer(ctx, traefikContainerInput); err != nil {
			return err
		}

		return nil
	}
}